Song Liu [Fri, 10 Sep 2021 18:33:50 +0000 (11:33 -0700)]
perf: Enable branch record for software events
The typical way to access branch record (e.g. Intel LBR) is via hardware
perf_event. For CPUs with FREEZE_LBRS_ON_PMI support, PMI could capture
reliable LBR. On the other hand, LBR could also be useful in non-PMI
scenario. For example, in kretprobe or bpf fexit program, LBR could
provide a lot of information on what happened with the function. Add API
to use branch record for software use.
Note that, when the software event triggers, it is necessary to stop the
branch record hardware asap. Therefore, static_call is used to remove some
branch instructions in this process.
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Song Liu <songliubraving@fb.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/bpf/20210910183352.3151445-2-songliubraving@fb.com
Vadim Fedorenko [Thu, 9 Sep 2021 22:04:09 +0000 (01:04 +0300)]
selftests/bpf: Test new __sk_buff field hwtstamp
Analogous to the gso_segs selftests introduced in commit
d9ff286a0f59
("bpf: allow BPF programs access skb_shared_info->gso_segs field").
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210909220409.8804-3-vfedorenko@novek.ru
Vadim Fedorenko [Thu, 9 Sep 2021 22:04:08 +0000 (01:04 +0300)]
bpf: Add hardware timestamp field to __sk_buff
BPF programs may want to know hardware timestamps if NIC supports
such timestamping.
Expose this data as hwtstamp field of __sk_buff the same way as
gso_segs/gso_size. This field could be accessed from the same
programs as tstamp field, but it's read-only field. Explicit test
to deny access to padding data is added to bpf_skb_is_valid_access.
Also update BPF_PROG_TEST_RUN tests of the feature.
Signed-off-by: Vadim Fedorenko <vfedorenko@novek.ru>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210909220409.8804-2-vfedorenko@novek.ru
Daniel Borkmann [Fri, 10 Sep 2021 19:15:32 +0000 (21:15 +0200)]
Merge branch 'bpf-xsk-selftests'
Magnus Karlsson says:
====================
This patch set facilitates adding new tests as well as describing
existing ones in the xsk selftests suite and adds 3 new test suites at
the end. The idea is to isolate the run-time that executes the test
from the actual implementation of the test. Today, implementing a test
amounts to adding test specific if-statements all around the run-time,
which is not scalable or amenable for reuse. This patch set instead
introduces a test specification that is the only thing that a test
fills in. The run-time then gets this specification and acts upon it
completely unaware of what test it is executing. This way, we can get
rid of all test specific if-statements from the run-time and the
implementation of the test can be contained in a single function. This
hopefully makes it easier to add tests and for users to understand
what the test accomplishes.
As a recap of what the run-time does: each test is based on the
run-time launching two threads and connecting a veth link between the
two threads. Each thread opens an AF_XDP socket on that veth interface
and one of them sends traffic that the other one receives and
validates. Each thread has its own umem. Note that this behavior is
not changed by this patch set.
A test specification consists of several items. Most importantly:
* Two packet streams. One for Tx thread that specifies what traffic to
send and one for the Rx thread that specifies what that thread
should receive. If it receives exactly what is specified, the test
passes, otherwise it fails. A packet stream can also specify what
buffers in the umem that should be used by the Rx and Tx threads.
* What kind of AF_XDP sockets it should create and bind to what
interfaces
* How many times it should repeat the socket creation and destruction
* The name of the test
The interface for the test spec is the following:
void test_spec_init(struct test_spec *test, struct ifobject *ifobj_tx,
struct ifobject *ifobj_rx, enum test_mode mode);
/* Reset everything but the interface specifications and the mode */
void test_spec_reset(struct test_spec *test);
void test_spec_set_name(struct test_spec *test, const char *name);
Packet streams have the following interfaces:
struct pkt *pkt_stream_get_pkt(struct pkt_stream *pkt_stream, u32 pkt_nb)
struct pkt *pkt_stream_get_next_rx_pkt(struct pkt_stream *pkt_stream)
struct pkt_stream *pkt_stream_generate(struct xsk_umem_info *umem,
u32 nb_pkts, u32 pkt_len);
void pkt_stream_delete(struct pkt_stream *pkt_stream);
struct pkt_stream *pkt_stream_clone(struct xsk_umem_info *umem,
struct pkt_stream *pkt_stream);
/* Replaces all packets in the stream*/
void pkt_stream_replace(struct test_spec *test, u32 nb_pkts, u32 pkt_len);
/* Replaces every other packet in the stream */
void pkt_stream_replace_half(struct test_spec *test, u32 pkt_len, u32 offset);
/* For creating custom made packet streams */
void pkt_stream_generate_custom(struct test_spec *test, struct pkt *pkts,
u32 nb_pkts);
/* Restores the default packet stream */
void pkt_stream_restore_default(struct test_spec *test);
A test can then then in the most basic case described like this
(provided the test specification has been created before calling the
function):
static bool testapp_aligned(struct test_spec *test)
{
test_spec_set_name(test, "RUN_TO_COMPLETION");
testapp_validate_traffic(test);
}
Running the same test in unaligned mode would then look like this:
static bool testapp_unaligned(struct test_spec *test)
{
if (!hugepages_present(test->ifobj_tx)) {
ksft_test_result_skip("No 2M huge pages present.\n");
return false;
}
test_spec_set_name(test, "UNALIGNED_MODE");
test->ifobj_tx->umem->unaligned_mode = true;
test->ifobj_rx->umem->unaligned_mode = true;
/* Let half of the packets straddle a buffer boundrary */
pkt_stream_replace_half(test, PKT_SIZE,
XSK_UMEM__DEFAULT_FRAME_SIZE - 32);
/* Populate fill ring with addresses in the packet stream */
test->ifobj_rx->pkt_stream->use_addr_for_fill = true;
testapp_validate_traffic(test);
pkt_stream_restore_default(test);
return true;
}
3 of the last 4 patches in the set add 3 new test suites, one for
unaligned mode, one for testing the rejection of tricky invalid
descriptors plus the acceptance of some valid ones in the Tx ring, and
one for testing 2K frame sizes (the default is 4K).
What is left to do for follow-up patches:
* Convert the statistics tests to the new framework.
* Implement a way of registering new tests without having the enum
test_type. Once this has been done (together with the previous
bullet), all the test types can be dropped from the header
file. This means that we should be able to add tests by just writing
a single function with a new test specification, which is one of the
goals.
* Introduce functions for manipulating parts of the test or interface
spec instead of direct manipulations such as
test->ifobj_rx->pkt_stream->use_addr_for_fill = true; which is kind
of awkward.
* Move the run-time and its interface to its own .c and .h files. Then
we can have all the tests in a separate file.
* Better error reporting if a test fails. Today it does not state what
test fails and might not continue execute the rest of the tests due
to this failure. Failures are not propagated upwards through the
functions so a failed test will also be a passed test, which messes
up the stats counting. This needs to be changed.
* Add option to run specific test instead of all of them
* Introduce pacing of sent packets so that they are never dropped
by the receiver even if it is stalled for some reason. If you run
the current tests on a heavily loaded system, they might fail in SKB
mode due to packets being dropped by the driver on Tx. Though I have
never seen it, it might happen.
v1 -> v2:
* Fixed a number of spelling errors [Maciej]
* Fixed use after free bug in pkt_stream_replace() [Maciej]
* pkt_stream_set -> pkt_stream_generate_custom [Maciej]
* Fixed formatting problem in testapp_invalid_desc() [Maciej]
====================
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Magnus Karlsson [Tue, 7 Sep 2021 07:19:28 +0000 (09:19 +0200)]
selftests: xsk: Add tests for 2K frame size
Add tests for 2K frame size. Both a standard send and receive test and
one testing for invalid descriptors when the frame size is 2K.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-21-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:27 +0000 (09:19 +0200)]
selftests: xsk: Add tests for invalid xsk descriptors
Add tests for invalid xsk descriptors in the Tx ring. A number of
handcrafted nasty invalid descriptors are created and submitted to the
tx ring to check that they are validated correctly. Corner case valid
ones are also sent. The tests are run for both aligned and unaligned
mode.
pkt_stream_set() is introduced to be able to create a hand-crafted
packet stream where every single packet is specified in detail.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-20-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:26 +0000 (09:19 +0200)]
selftests: xsk: Eliminate test specific if-statement in test runner
Eliminate a test specific if-statement for the RX_FILL_EMTPY stats
test that is present in the test runner. We can do this as we now have
the use_addr_for_fill option. Just create and empty Rx packet stream
and indicated that the test runner should use the addresses in that to
populate the fill ring. As there are no packets in the stream, the
fill ring will be empty and we will get the error stats that we want
to test.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-19-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:25 +0000 (09:19 +0200)]
selftests: xsk: Add test for unaligned mode
Add a test for unaligned mode in which packet buffers can be placed
anywhere within the umem. Some packets are made to straddle page
boundaries in order to check for correctness. On the Tx side, buffers
are now allocated according to the addresses found in the packet
stream. Thus, the placement of buffers can be controlled with the
boolean use_addr_for_fill in the packet stream.
One new pkt_stream interface is introduced: pkt_stream_replace_half()
that replaces every other packet in the default packet stream with the
specified new packet. The constant DEFAULT_OFFSET is also
introduced. It specifies at what offset from the start of a chunk a Tx
packet is placed by the sending thread. This is just to be able to
test that it is possible to send packets at an offset not equal to
zero.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-18-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:24 +0000 (09:19 +0200)]
selftests: xsk: Introduce replacing the default packet stream
Introduce the concept of a default packet stream that is the set of
packets sent by most tests. Then add the ability to replace it for a
test that would like to send or receive something else through the use
of the function pkt_stream_replace() and then restored with
pkt_stream_restore_default(). These are then used to convert the
STAT_TEST_TX_INVALID to use these new APIs.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-17-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:23 +0000 (09:19 +0200)]
selftests: xsk: Allow for invalid packets
Allow for invalid packets to be sent. These are verified by the Rx
thread not to be received. Or put in another way, if they are
received, the test will fail. This feature will be used to eliminate
an if statement for a stats test and will also be used by other tests
in later patches. The previous code could only deal with valid
packets.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-16-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:22 +0000 (09:19 +0200)]
selftests: xsk: Eliminate MAX_SOCKS define
Remove the MAX_SOCKS define as it always will be one for the forseable
future and the code does not work for any other case anyway.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-15-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:21 +0000 (09:19 +0200)]
selftests: xsx: Make pthreads local scope
Make the pthread_t variables local scope instead of global. No reason
for them to be global.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-14-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:20 +0000 (09:19 +0200)]
selftests: xsk: Make xdp_flags and bind_flags local
Make xdp_flags and bind_flags local instead of global by moving them
into the interface object. These flags decide if the socket should be
created in SKB mode or in DRV mode and therefore they are sticky and
will survive a test_spec_reset. Since every test is first run in SKB
mode then in DRV mode, this change only happens once. With this
change, the configured_mode global variable can also be
erradicated. The first test_spec_init() also becomes superfluous and
can be eliminated.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-13-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:19 +0000 (09:19 +0200)]
selftests: xsk: Specify number of sockets to create
Add the ability in the test specification to specify numbers of
sockets to create. The default is one socket. This is then used to
remove test specific if-statements around the bpf_res tests.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-12-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:18 +0000 (09:19 +0200)]
selftests: xsk: Replace second_step global variable
Replace the second_step global variable with a test specification
variable called total_steps that a test can be set to indicate how
many times the packet stream should be sent without reinitializing any
sockets. This eliminates test specific code in the test runner around
the bidirectional test.
The total_steps variable is 1 by default as most tests only need a
single round of packets.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-11-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:17 +0000 (09:19 +0200)]
selftests: xsk: Introduce rx_on and tx_on in ifobject
Introduce rx_on and tx_on in the ifobject so that we can describe if
the thread should create a socket with only tx, rx, or both. This
eliminates some test specific if statements from the code. We can also
eliminate the flow vector structure now as this is fully specified
by the tx_on and rx_on variables.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-10-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:16 +0000 (09:19 +0200)]
selftests: xsk: Add use_poll to ifobject
Add a use_poll option to the ifobject so that we do not need to use a
test specific if-statement in the test runner.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-9-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:15 +0000 (09:19 +0200)]
selftests: xsx: Introduce test name in test spec
Introduce the test name in the test specification. This so we can set
the name locally in the test function and simplify the logic for
printing out test results.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-8-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:14 +0000 (09:19 +0200)]
selftests: xsk: Make frame_size configurable
Make the frame size configurable instead of it being hard coded to a
default. This is a property of the umem and will make it possible to
implement tests for different umem frame sizes in a later patch.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-7-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:13 +0000 (09:19 +0200)]
selftests: xsk: Move rxqsize into xsk_socket_info
Move the global variable rxqsize to struct xsk_socket_info as it
describes the size of a ring in that struct. By default, it is set to
the size dictated by libbpf.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-6-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:12 +0000 (09:19 +0200)]
selftests: xsk: Move num_frames and frame_headroom to xsk_umem_info
Move the global variables num_frames and frame_headroom to struct
xsk_umem_info. They describe properties of the umem so no reason for
them to be global.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-5-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:11 +0000 (09:19 +0200)]
selftests: xsk: Introduce test specifications
Introduce a test specification to be able to concisely describe a
test. Currently, a test is implemented by sprinkling test specific if
statements here and there, which is not scalable or easy to
understand. The end goal with this patch set is to come to the point
in which a test is completely specified by a test specification that
can easily be constructed in a single function so that new tests can
be added without too much trouble. This test specification will be run
by a test runner that has no idea about tests. It just executes the
what test specification states.
This patch introduces the test specification and, as a start, puts the
two interface objects in there, one containing the packet stream to be
sent and the other one the packet stream that is supposed to be
received for a test to pass. The global variables containing these can
then be eliminated. The following patches will convert each existing
test into a test specification and add the needed fields into it and
the functionality in the test runner that act on the test
specification. At the end, the test runner should contain no test
specific code and each test should be described in a single simple
function.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-4-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:10 +0000 (09:19 +0200)]
selftests: xsk: Introduce type for thread function
Introduce a typedef of the thread function so this can be passed to
init_iface() in order to simplify that function.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-3-magnus.karlsson@gmail.com
Magnus Karlsson [Tue, 7 Sep 2021 07:19:09 +0000 (09:19 +0200)]
selftests: xsk: Simplify xsk and umem arrays
Simplify the xsk_info and umem_info allocation by allocating them
upfront in an array, instead of allocating an array of pointers to
future creations of these. Allocating them upfront also has the
advantage that configuration information can be stored in these
structures instead of relying on global variables. With the previous
structure, xsk_info and umem_info were created too late to be able to
store most configuration information. This will be used to eliminate
most global variables in later patches in this series.
Signed-off-by: Magnus Karlsson <magnus.karlsson@intel.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: Maciej Fijalkowski <maciej.fijalkowski@intel.com>
Link: https://lore.kernel.org/bpf/20210907071928.9750-2-magnus.karlsson@gmail.com
Quentin Monnet [Wed, 8 Sep 2021 21:32:26 +0000 (14:32 -0700)]
libbpf: Add LIBBPF_DEPRECATED_SINCE macro for scheduling API deprecations
Introduce a macro LIBBPF_DEPRECATED_SINCE(major, minor, message) to prepare
the deprecation of two API functions. This macro marks functions as deprecated
when libbpf's version reaches the values passed as an argument.
As part of this change libbpf_version.h header is added with recorded major
(LIBBPF_MAJOR_VERSION) and minor (LIBBPF_MINOR_VERSION) libbpf version macros.
They are now part of libbpf public API and can be relied upon by user code.
libbpf_version.h is installed system-wide along other libbpf public headers.
Due to this new build-time auto-generated header, in-kernel applications
relying on libbpf (resolve_btfids, bpftool, bpf_preload) are updated to
include libbpf's output directory as part of a list of include search paths.
Better fix would be to use libbpf's make_install target to install public API
headers, but that clean up is left out as a future improvement. The build
changes were tested by building kernel (with KBUILD_OUTPUT and O= specified
explicitly), bpftool, libbpf, selftests/bpf, and resolve_btfids builds. No
problems were detected.
Note that because of the constraints of the C preprocessor we have to write
a few lines of macro magic for each version used to prepare deprecation (0.6
for now).
Also, use LIBBPF_DEPRECATED_SINCE() to schedule deprecation of
btf__get_from_id() and btf__load(), which are replaced by
btf__load_from_kernel_by_id() and btf__load_into_kernel(), respectively,
starting from future libbpf v0.6. This is part of libbpf 1.0 effort ([0]).
[0] Closes: https://github.com/libbpf/libbpf/issues/278
Co-developed-by: Quentin Monnet <quentin@isovalent.com>
Co-developed-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Quentin Monnet <quentin@isovalent.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Link: https://lore.kernel.org/bpf/20210908213226.1871016-1-andrii@kernel.org
Andrii Nakryiko [Tue, 7 Sep 2021 22:10:23 +0000 (15:10 -0700)]
libbpf: Fix build with latest gcc/binutils with LTO
After updating to binutils 2.35, the build began to fail with an
assembler error. A bug was opened on the Red Hat Bugzilla a few days
later for the same issue.
Work around the problem by using the new `symver` attribute (introduced
in GCC 10) as needed instead of assembler directives.
This addresses Red Hat ([0]) and OpenSUSE ([1]) bug reports, as well as libbpf
issue ([2]).
[0]: https://bugzilla.redhat.com/show_bug.cgi?id=1863059
[1]: https://bugzilla.opensuse.org/show_bug.cgi?id=1188749
[2]: Closes: https://github.com/libbpf/libbpf/issues/338
Co-developed-by: Patrick McCarty <patrick.mccarty@intel.com>
Co-developed-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Patrick McCarty <patrick.mccarty@intel.com>
Signed-off-by: Michal Suchanek <msuchanek@suse.de>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210907221023.2660953-1-andrii@kernel.org
Andrii Nakryiko [Wed, 8 Sep 2021 00:32:10 +0000 (17:32 -0700)]
Merge branch 'Bpf skeleton helper method'
Matt Smith says:
====================
This patch series changes the type of bpf_object_skeleton->data
to const void * and provides a helper method X__elf_bytes(size_t *sz)
for accessing the raw binary data of the compiled embedded BPF object.
The type change enforces the previously implied behavior of immutability
for this field while casting it to (void *) before assignment allows
for compiling with previous versions of the libbpf headers without
compiler warnings.
The helper method allows easier access to the BPF binary object data
and is leveraged to populate the skeleton field. The inclusion of
this helper method will allow users to get access to the data without
needing to populate an entire skeleton first.
Checks are added in the third patch to validate the behavior of the
added method
====================
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Matt Smith [Wed, 1 Sep 2021 19:44:39 +0000 (12:44 -0700)]
selftests/bpf: Add checks for X__elf_bytes() skeleton helper
This patch adds two checks for the X__elf_bytes BPF skeleton helper
method. The first asserts that the pointer returned from the helper
method is valid, the second asserts that the provided size pointer is
set.
Signed-off-by: Matt Smith <alastorze@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210901194439.3853238-4-alastorze@fb.com
Matt Smith [Wed, 1 Sep 2021 19:44:38 +0000 (12:44 -0700)]
bpftool: Provide a helper method for accessing skeleton's embedded ELF data
This adds a skeleton method X__elf_bytes() which returns the binary data of
the compiled and embedded BPF object file. It additionally sets the size of
the return data to the provided size_t pointer argument.
The assignment to s->data is cast to void * to ensure no warning is issued if
compiled with a previous version of libbpf where the bpf_object_skeleton field
is void * instead of const void *
Signed-off-by: Matt Smith <alastorze@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210901194439.3853238-3-alastorze@fb.com
Matt Smith [Wed, 1 Sep 2021 19:44:37 +0000 (12:44 -0700)]
libbpf: Change bpf_object_skeleton data field to const pointer
This change was necessary to enforce the implied contract
that bpf_object_skeleton->data should not be mutated. The data
will be cast to `void *` during assignment to handle the case
where a user is compiling with older libbpf headers to avoid
a compiler warning of `const void *` data being cast to `void *`
Signed-off-by: Matt Smith <alastorze@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210901194439.3853238-2-alastorze@fb.com
Toke Høiland-Jørgensen [Wed, 1 Sep 2021 11:48:12 +0000 (13:48 +0200)]
libbpf: Don't crash on object files with no symbol tables
If libbpf encounters an ELF file that has been stripped of its symbol
table, it will crash in bpf_object__add_programs() when trying to
dereference the obj->efile.symbols pointer.
Fix this by erroring out of bpf_object__elf_collect() if it is not able
able to find the symbol table.
v2:
- Move check into bpf_object__elf_collect() and add nice error message
Fixes:
6245947c1b3c ("libbpf: Allow gaps in BPF program sections to support overriden weak functions")
Signed-off-by: Toke Høiland-Jørgensen <toke@redhat.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Link: https://lore.kernel.org/bpf/20210901114812.204720-1-toke@redhat.com
Neil Spring [Tue, 31 Aug 2021 03:33:56 +0000 (20:33 -0700)]
bpf: Permit ingress_ifindex in bpf_prog_test_run_xattr
bpf_prog_test_run_xattr takes a struct __sk_buff, but did not permit
that __skbuff to include an nonzero ingress_ifindex.
This patch updates to allow ingress_ifindex, convert the __sk_buff field to
sk_buff (skb_iif) and back, and tests that the value is present from on BPF
program side. The test sets an unlikely distinct value for ingress_ifindex
(11) from ifindex (1), which is in line with the rest of the synthetic field
tests.
Adding this support allows testing BPF that operates differently on
incoming and outgoing skbs by discriminating on this field.
Signed-off-by: Neil Spring <ntspring@fb.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20210831033356.1459316-1-ntspring@fb.com
Linus Torvalds [Sun, 5 Sep 2021 18:56:18 +0000 (11:56 -0700)]
Merge tag 'perf-tools-for-v5.15-2021-09-04' of git://git./linux/kernel/git/acme/linux
Pull perf tool updates from Arnaldo Carvalho de Melo:
"New features:
- Improvements for the flamegraph python script, including:
- Display perf.data header
- Display PIDs of user stacks
- Added option to change color scheme
- Default to blue/green color scheme to improve accessibility
- Correctly identify kernel stacks when debuginfo is available
- Improvements for 'perf bench futex':
- Add --mlockall parameter
- Add --broadcast and --pi to the 'requeue' sub benchmark
- Add support for PMU aliases.
- Introduce an ARM Coresight ETE decoder.
- Add a 'perf bench' entry for evlist open/close operations, to help
quantify improvements with multithreading 'perf record'.
- Allow reporting the [un]throttle PERF_RECORD_ meta event in 'perf
script's python scripting.
- Add a 'perf test' entry for PMU aliases.
- Add a 'perf test' entry for 'perf record/perf report/perf script'
pipe mode.
Fixes:
- perf script dlfilter (API for filtering via dynamically loaded
shared object introduced in v5.14) fixes and a 'perf test' entry
for it.
- Fix get_current_dir_name() compilation on Android.
- Fix issues with asciidoc and double dashes uses.
- Fix memory leaks in the BTF handling code.
- Fix leftover problems in the Documentation from the infrastructure
originally lifted from the git codebase.
- Fix *probe_vfs_getname.sh 'perf test' failures.
- Handle fd gaps in 'perf test's test__dso_data_reopen().
- Make sure to show disasembly warnings for 'perf annotate --stdio'.
- Fix output from pipe to file and vice-versa in 'perf
record/report/script'.
- Correct 'perf data -h' output.
- Fix wrong comm in system-wide mode with 'perf record --delay'.
- Do not allow --for-each-cgroup without cpu in 'perf stat'
- Make 'perf test --skip' work on shell tests.
- Fix libperf's verbose printing.
Misc improvements:
- Preparatory patches for multithreading various 'perf record' phases
(synthesizing, opening, recording, etc).
- Add sparse context/locking annotations in compiler-types.h, also to
help with the multithreading effort.
- Optimize the generation of the arch specific erno tables used in
'perf trace'.
- Optimize libperf's perf_cpu_map__max().
- Improve ARM's CoreSight warnings.
- Report collisions in AUX records.
- Improve warnings for the LLVM 'perf test' entry.
- Improve the PMU events 'perf test' codebase.
- perf test: Do not compare overheads in the zstd comp test
- Better support annotation on ARM.
- Update 'perf trace's cmd string table to decode sys_bpf() first
arg.
Vendor events:
- Add JSON events and metrics for Intel's Ice Lake, Tiger Lake and
Elhart Lake.
- Update JSON eventsand metrics for Intel's Cascade Lake and Sky Lake
servers.
Hardware tracing:
- Improvements for the ARM hardware tracing auxtrace support"
* tag 'perf-tools-for-v5.15-2021-09-04' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux: (130 commits)
perf tests: Add test for PMU aliases
perf pmu: Add PMU alias support
perf session: Report collisions in AUX records
perf script python: Allow reporting the [un]throttle PERF_RECORD_ meta event
perf build: Report failure for testing feature libopencsd
perf cs-etm: Show a warning for an unknown magic number
perf cs-etm: Print the decoder name
perf cs-etm: Create ETE decoder
perf cs-etm: Update OpenCSD decoder for ETE
perf cs-etm: Fix typo
perf cs-etm: Save TRCDEVARCH register
perf cs-etm: Refactor out ETMv4 header saving
perf cs-etm: Initialise architecture based on TRCIDR1
perf cs-etm: Refactor initialisation of decoder params.
tools build: Fix feature detect clean for out of source builds
perf evlist: Add evlist__for_each_entry_from() macro
perf evsel: Handle precise_ip fallback in evsel__open_cpu()
perf evsel: Move bpf_counter__install_pe() to success path in evsel__open_cpu()
perf evsel: Move test_attr__open() to success path in evsel__open_cpu()
perf evsel: Move ignore_missing_thread() to fallback code
...
Linus Torvalds [Sun, 5 Sep 2021 18:50:41 +0000 (11:50 -0700)]
Merge tag 'trace-v5.15' of git://git./linux/kernel/git/rostedt/linux-trace
Pull tracing updates from Steven Rostedt:
- simplify the Kconfig use of FTRACE and TRACE_IRQFLAGS_SUPPORT
- bootconfig can now start histograms
- bootconfig supports group/all enabling
- histograms now can put values in linear size buckets
- execnames can be passed to synthetic events
- introduce "event probes" that attach to other events and can retrieve
data from pointers of fields, or record fields as different types (a
pointer to a string as a string instead of just a hex number)
- various fixes and clean ups
* tag 'trace-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/rostedt/linux-trace: (35 commits)
tracing/doc: Fix table format in histogram code
selftests/ftrace: Add selftest for testing duplicate eprobes and kprobes
selftests/ftrace: Add selftest for testing eprobe events on synthetic events
selftests/ftrace: Add test case to test adding and removing of event probe
selftests/ftrace: Fix requirement check of README file
selftests/ftrace: Add clear_dynamic_events() to test cases
tracing: Add a probe that attaches to trace events
tracing/probes: Reject events which have the same name of existing one
tracing/probes: Have process_fetch_insn() take a void * instead of pt_regs
tracing/probe: Change traceprobe_set_print_fmt() to take a type
tracing/probes: Use struct_size() instead of defining custom macros
tracing/probes: Allow for dot delimiter as well as slash for system names
tracing/probe: Have traceprobe_parse_probe_arg() take a const arg
tracing: Have dynamic events have a ref counter
tracing: Add DYNAMIC flag for dynamic events
tracing: Replace deprecated CPU-hotplug functions.
MAINTAINERS: Add an entry for os noise/latency
tracepoint: Fix kerneldoc comments
bootconfig/tracing/ktest: Update ktest example for boot-time tracing
tools/bootconfig: Use per-group/all enable option in ftrace2bconf script
...
Linus Torvalds [Sun, 5 Sep 2021 18:43:03 +0000 (11:43 -0700)]
Merge tag 'arc-5.15-rc1' of git://git./linux/kernel/git/vgupta/arc
Pull ARC updates from Vineet Gupta:
"Finally a big pile of changes for ARC (atomics/mm). These are from our
internal arc64 tree, preparing mainline for eventual arc64 support.
I'm spreading them out to avoid tsunami of patches in one release.
- MM rework:
- Implement up to 4 paging levels
- Enable STRICT_MM_TYPECHECK
- switch pgtable_t back to 'struct page *'
- Atomics rework / implement relaxed accessors
- Retire legacy MMUv1,v2; ARC750 cores
- A few other build errors, typos"
* tag 'arc-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/vgupta/arc: (33 commits)
ARC: mm: vmalloc sync from kernel to user table to update PMD ...
ARC: mm: support 4 levels of page tables
ARC: mm: support 3 levels of page tables
ARC: mm: switch to asm-generic/pgalloc.h
ARC: mm: switch pgtable_t back to struct page *
ARC: mm: hack to allow 2 level build with 4 level code
ARC: mm: disintegrate pgtable.h into levels and flags
ARC: mm: disintegrate mmu.h (arcv2 bits out)
ARC: mm: move MMU specific bits out of entry code ...
ARC: mm: move MMU specific bits out of ASID allocator
ARC: mm: non-functional code movement/cleanup
ARC: mm: pmd_populate* to use the canonical set_pmd (and drop pmd_set)
ARC: ioremap: use more commonly used PAGE_KERNEL based uncached flag
ARC: mm: Enable STRICT_MM_TYPECHECKS
ARC: mm: Fixes to allow STRICT_MM_TYPECHECKS
ARC: mm: move mmu/cache externs out to setup.h
ARC: mm: remove tlb paranoid code
ARC: mm: use SCRATCH_DATA0 register for caching pgdir in ARCv2 only
ARC: retire MMUv1 and MMUv2 support
ARC: retire ARC750 support
...
Linus Torvalds [Sun, 5 Sep 2021 18:31:23 +0000 (11:31 -0700)]
Merge tag 'riscv-for-linus-5.15-mw0' of git://git./linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt:
- support PC-relative instructions (auipc and branches) in kprobes
- support for forced IRQ threading
- support for the hlt/nohlt kernel command line options, via the
generic idle loop
- show the edge/level triggered behavior of interrupts
in /proc/interrupts
- a handful of cleanups to our address mapping mechanisms
- support for allocating gigantic hugepages via CMA
- support for the undefined behavior sanitizer (UBSAN)
- a handful of cleanups to the VDSO that allow the kernel to build with
LLD.
- support for hugepage migration
* tag 'riscv-for-linus-5.15-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (21 commits)
riscv: add support for hugepage migration
RISC-V: Fix VDSO build for !MMU
riscv: use strscpy to replace strlcpy
riscv: explicitly use symbol offsets for VDSO
riscv: Enable Undefined Behavior Sanitizer UBSAN
riscv: Keep the riscv Kconfig selects sorted
riscv: Support allocating gigantic hugepages using CMA
riscv: fix the global name pfn_base confliction error
riscv: Move early fdt mapping creation in its own function
riscv: Simplify BUILTIN_DTB device tree mapping handling
riscv: Use __maybe_unused instead of #ifdefs around variable declarations
riscv: Get rid of map_size parameter to create_kernel_page_table
riscv: Introduce va_kernel_pa_offset for 32-bit kernel
riscv: Optimize kernel virtual address conversion macro
dt-bindings: riscv: add starfive jh7100 bindings
riscv: Enable GENERIC_IRQ_SHOW_LEVEL
riscv: Enable idle generic idle loop
riscv: Allow forced irq threading
riscv: Implement thread_struct whitelist for hardened usercopy
riscv: kprobes: implement the branch instructions
...
Linus Torvalds [Sun, 5 Sep 2021 18:24:05 +0000 (11:24 -0700)]
Enable '-Werror' by default for all kernel builds
... but make it a config option so that broken environments can disable
it when required.
We really should always have a clean build, and will disable specific
over-eager warnings as required, if we can't fix them. But while I
fairly religiously enforce that in my own tree, it doesn't get enforced
by various build robots that don't necessarily report warnings.
So this just makes '-Werror' a default compiler flag, but allows people
to disable it for their configuration if they have some particular
issues.
Occasionally, new compiler versions end up enabling new warnings, and it
can take a while before we have them fixed (or the warnings disabled if
that is what it takes), so the config option allows for that situation.
Hopefully this will mean that I get fewer pull requests that have new
warnings that were not noticed by various automation we have in place.
Knock wood.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sun, 5 Sep 2021 18:19:15 +0000 (11:19 -0700)]
Merge tag 'usb-5.15-rc1-2' of git://git./linux/kernel/git/gregkh/usb
Pull more USB updates from Greg KH:
"Here are some straggler USB-serial changes for 5.15-rc1.
These were not included in the first pull request as they came in
"late" from Johan and I had missed them in my pull request earlier
this week.
Nothing big in here, just some USB to serial driver updates and fixes.
All of these were in linux-next before I pulled them into my tree, and
have been in linux-next all this week from my tree with no reported
problems"
* tag 'usb-5.15-rc1-2' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb:
USB: serial: pl2303: fix GL type detection
USB: serial: replace symbolic permissions by octal permissions
USB: serial: cp210x: determine fw version for CP2105 and CP2108
USB: serial: cp210x: clean up type detection
USB: serial: cp210x: clean up set-chars request
USB: serial: cp210x: clean up control-request timeout
USB: serial: cp210x: fix flow-control error handling
USB: serial: cp210x: fix control-characters error handling
USB: serial: io_edgeport: drop unused descriptor helper
Linus Torvalds [Sun, 5 Sep 2021 17:50:12 +0000 (10:50 -0700)]
Merge tag 'mtd/for-5.15' of git://git./linux/kernel/git/mtd/linux
Pull MTD updates from Miquel Raynal:
"MTD changes:
- blkdevs:
- Simplify the refcounting in blktrans_{open, release}
- Simplify blktrans_getgeo
- Remove blktrans_ref_mutex
- Simplify blktrans_dev_get
- Use lockdep_assert_held
- Don't hold del_mtd_blktrans_dev in blktrans_{open, release}
- ftl:
- Don't cast away the type when calling add_mtd_blktrans_dev
- Don't cast away the type when calling add_mtd_blktrans_dev
- Use container_of() rather than cast
- Fix use-after-free
- Add discard support
- Allow use of MTD_RAM for testing purposes
- concat:
- Check _read, _write callbacks existence before assignment
- Judge callback existence based on the master
- maps:
- Maps: remove dead MTD map driver for PMC-Sierra MSP boards
- mtdblock:
- Warn if added for a NAND device
- Add comment about UBI block devices
- Update old JFFS2 mention in Kconfig
- partitions:
- Redboot: convert to YAML
NAND core changes:
- Repair Miquel Raynal's email address in MAINTAINERS
- Fix a couple of spelling mistakes in Kconfig
- bbt: Skip bad blocks when searching for the BBT in NAND
- Remove never changed ret variable
Raw NAND changes:
- cafe: Fix a resource leak in the error handling path of 'cafe_nand_probe()'
- intel: Fix error handling in probe
- omap: Fix kernel doc warning on 'calcuate' typo
- gpmc: Fix the ECC bytes vs. OOB bytes equation
SPI-NAND core changes:
- Properly fill the OOB area.
- Fix comment
SPI-NAND drivers changes:
- macronix: Add Quad support for serial NAND flash"
* tag 'mtd/for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mtd/linux: (30 commits)
mtd: rawnand: cafe: Fix a resource leak in the error handling path of 'cafe_nand_probe()'
mtd_blkdevs: simplify the refcounting in blktrans_{open, release}
mtd_blkdevs: simplify blktrans_getgeo
mtd_blkdevs: remove blktrans_ref_mutex
mtd_blkdevs: simplify blktrans_dev_get
mtd/rfd_ftl: don't cast away the type when calling add_mtd_blktrans_dev
mtd/ftl: don't cast away the type when calling add_mtd_blktrans_dev
mtd_blkdevs: use lockdep_assert_held
mtd_blkdevs: don't hold del_mtd_blktrans_dev in blktrans_{open, release}
mtd: rawnand: intel: Fix error handling in probe
mtd: mtdconcat: Check _read, _write callbacks existence before assignment
mtd: mtdconcat: Judge callback existence based on the master
mtd: maps: remove dead MTD map driver for PMC-Sierra MSP boards
mtd: rfd_ftl: use container_of() rather than cast
mtd: rfd_ftl: fix use-after-free
mtd: rfd_ftl: add discard support
mtd: rfd_ftl: allow use of MTD_RAM for testing purposes
mtdblock: Warn if added for a NAND device
mtd: spinand: macronix: Add Quad support for serial NAND flash
mtdblock: Add comment about UBI block devices
...
Geert Uytterhoeven [Sun, 5 Sep 2021 09:30:34 +0000 (11:30 +0200)]
binfmt: a.out: Fix bogus semicolon
fs/binfmt_aout.c: In function ‘load_aout_library’:
fs/binfmt_aout.c:311:27: error: expected ‘)’ before ‘;’ token
311 | MAP_FIXED | MAP_PRIVATE;
| ^
fs/binfmt_aout.c:309:10: error: too few arguments to function ‘vm_mmap’
309 | error = vm_mmap(file, start_addr, ex.a_text + ex.a_data,
| ^~~~~~~
In file included from fs/binfmt_aout.c:12:
include/linux/mm.h:2626:35: note: declared here
2626 | extern unsigned long __must_check vm_mmap(struct file *, unsigned long,
| ^~~~~~~
Fix this by reverting the accidental replacement of a comma by a
semicolon.
Fixes:
42be8b42535183f8 ("binfmt: don't use MAP_DENYWRITE when loading shared libraries via uselib()")
Reported-by: noreply@ellerman.id.au
Reported-by: Guenter Roeck <linux@roeck-us.net>
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Linus Torvalds [Sat, 4 Sep 2021 18:35:47 +0000 (11:35 -0700)]
Merge tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux
Pull MAP_DENYWRITE removal from David Hildenbrand:
"Remove all in-tree usage of MAP_DENYWRITE from the kernel and remove
VM_DENYWRITE.
There are some (minor) user-visible changes:
- We no longer deny write access to shared libaries loaded via legacy
uselib(); this behavior matches modern user space e.g. dlopen().
- We no longer deny write access to the elf interpreter after exec
completed, treating it just like shared libraries (which it often
is).
- We always deny write access to the file linked via /proc/pid/exe:
sys_prctl(PR_SET_MM_MAP/EXE_FILE) will fail if write access to the
file cannot be denied, and write access to the file will remain
denied until the link is effectivel gone (exec, termination,
sys_prctl(PR_SET_MM_MAP/EXE_FILE)) -- just as if exec'ing the file.
Cross-compiled for a bunch of architectures (alpha, microblaze, i386,
s390x, ...) and verified via ltp that especially the relevant tests
(i.e., creat07 and execve04) continue working as expected"
* tag 'denywrite-for-5.15' of git://github.com/davidhildenbrand/linux:
fs: update documentation of get_write_access() and friends
mm: ignore MAP_DENYWRITE in ksys_mmap_pgoff()
mm: remove VM_DENYWRITE
binfmt: remove in-tree usage of MAP_DENYWRITE
kernel/fork: always deny write access to current MM exe_file
kernel/fork: factor out replacing the current MM exe_file
binfmt: don't use MAP_DENYWRITE when loading shared libraries via uselib()
Linus Torvalds [Sat, 4 Sep 2021 18:15:50 +0000 (11:15 -0700)]
Merge git://github.com/Paragon-Software-Group/linux-ntfs3
Merge NTFSv3 filesystem from Konstantin Komarov:
"This patch adds NTFS Read-Write driver to fs/ntfs3.
Having decades of expertise in commercial file systems development and
huge test coverage, we at Paragon Software GmbH want to make our
contribution to the Open Source Community by providing implementation
of NTFS Read-Write driver for the Linux Kernel.
This is fully functional NTFS Read-Write driver. Current version works
with NTFS (including v3.1) and normal/compressed/sparse files and
supports journal replaying.
We plan to support this version after the codebase once merged, and
add new features and fix bugs. For example, full journaling support
over JBD will be added in later updates"
Link: https://lore.kernel.org/lkml/20210729134943.778917-1-almaz.alexandrovich@paragon-software.com/
Link: https://lore.kernel.org/lkml/aa4aa155-b9b2-9099-b7a2-349d8d9d8fbd@paragon-software.com/
* git://github.com/Paragon-Software-Group/linux-ntfs3: (35 commits)
fs/ntfs3: Change how module init/info messages are displayed
fs/ntfs3: Remove GPL boilerplates from decompress lib files
fs/ntfs3: Remove unnecessary condition checking from ntfs_file_read_iter
fs/ntfs3: Fix integer overflow in ni_fiemap with fiemap_prep()
fs/ntfs3: Restyle comments to better align with kernel-doc
fs/ntfs3: Rework file operations
fs/ntfs3: Remove fat ioctl's from ntfs3 driver for now
fs/ntfs3: Restyle comments to better align with kernel-doc
fs/ntfs3: Fix error handling in indx_insert_into_root()
fs/ntfs3: Potential NULL dereference in hdr_find_split()
fs/ntfs3: Fix error code in indx_add_allocate()
fs/ntfs3: fix an error code in ntfs_get_acl_ex()
fs/ntfs3: add checks for allocation failure
fs/ntfs3: Use kcalloc/kmalloc_array over kzalloc/kmalloc
fs/ntfs3: Do not use driver own alloc wrappers
fs/ntfs3: Use kernel ALIGN macros over driver specific
fs/ntfs3: Restyle comment block in ni_parse_reparse()
fs/ntfs3: Remove unused including <linux/version.h>
fs/ntfs3: Fix fall-through warnings for Clang
fs/ntfs3: Fix one none utf8 char in source file
...
Linus Torvalds [Sat, 4 Sep 2021 17:48:47 +0000 (10:48 -0700)]
Merge tag 'f2fs-for-5.15-rc1' of git://git./linux/kernel/git/jaegeuk/f2fs
Pull f2fs updates from Jaegeuk Kim:
"In this cycle, we've addressed some performance issues such as lock
contention, misbehaving compress_cache, allowing extent_cache for
compressed files, and new sysfs to adjust ra_size for fadvise.
In order to diagnose the performance issues quickly, we also added an
iostat which shows the IO latencies periodically.
On the stability side, we've found two memory leakage cases in the
error path in compression flow. And, we've also fixed various corner
cases in fiemap, quota, checkpoint=disable, zstd, and so on.
Enhancements:
- avoid long checkpoint latency by releasing nat_tree_lock
- collect and show iostats periodically
- support extent_cache for compressed files
- add a sysfs entry to manage ra_size given fadvise(POSIX_FADV_SEQUENTIAL)
- report f2fs GC status via sysfs
- add discard_unit=%s in mount option to handle zoned device
Bug fixes:
- fix two memory leakages when an error happens in the compressed IO flow
- fix commpress_cache to get the right LBA
- fix fiemap to deal with compressed case correctly
- fix wrong EIO returns due to SBI_NEED_FSCK
- fix missing writes when enabling checkpoint back
- fix quota deadlock
- fix zstd level mount option
In addition to the above major updates, we've cleaned up several code
paths such as dio, unnecessary operations, debugfs/f2fs/status, sanity
check, and typos"
* tag 'f2fs-for-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jaegeuk/f2fs: (46 commits)
f2fs: should put a page beyond EOF when preparing a write
f2fs: deallocate compressed pages when error happens
f2fs: enable realtime discard iff device supports discard
f2fs: guarantee to write dirty data when enabling checkpoint back
f2fs: fix to unmap pages from userspace process in punch_hole()
f2fs: fix unexpected ENOENT comes from f2fs_map_blocks()
f2fs: fix to account missing .skipped_gc_rwsem
f2fs: adjust unlock order for cleanup
f2fs: Don't create discard thread when device doesn't support realtime discard
f2fs: rebuild nat_bits during umount
f2fs: introduce periodic iostat io latency traces
f2fs: separate out iostat feature
f2fs: compress: do sanity check on cluster
f2fs: fix description about main_blkaddr node
f2fs: convert S_IRUGO to 0444
f2fs: fix to keep compatibility of fault injection interface
f2fs: support fault injection for f2fs_kmem_cache_alloc()
f2fs: compress: allow write compress released file after truncate to zero
f2fs: correct comment in segment.h
f2fs: improve sbi status info in debugfs/f2fs/status
...
Linus Torvalds [Sat, 4 Sep 2021 17:25:26 +0000 (10:25 -0700)]
Merge tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs
Pull NFS client updates from Anna Schumaker:
"New Features:
- Better client responsiveness when server isn't replying
- Use refcount_t in sunrpc rpc_client refcount tracking
- Add srcaddr and dst_port to the sunrpc sysfs info files
- Add basic support for connection sharing between servers with multiple NICs`
Bugfixes and Cleanups:
- Sunrpc tracepoint cleanups
- Disconnect after ib_post_send() errors to avoid deadlocks
- Fix for tearing down rpcrdma_reps
- Fix a potential pNFS layoutget livelock loop
- pNFS layout barrier fixes
- Fix a potential memory corruption in rpc_wake_up_queued_task_set_status()
- Fix reconnection locking
- Fix return value of get_srcport()
- Remove rpcrdma_post_sends()
- Remove pNFS dead code
- Remove copy size restriction for inter-server copies
- Overhaul the NFS callback service
- Clean up sunrpc TCP socket shutdowns
- Always provide aligned buffers to RPC read layers"
* tag 'nfs-for-5.15-1' of git://git.linux-nfs.org/projects/anna/linux-nfs: (39 commits)
NFS: Always provide aligned buffers to the RPC read layers
NFSv4.1 add network transport when session trunking is detected
SUNRPC enforce creation of no more than max_connect xprts
NFSv4 introduce max_connect mount options
SUNRPC add xps_nunique_destaddr_xprts to xprt_switch_info in sysfs
SUNRPC keep track of number of transports to unique addresses
NFSv3: Delete duplicate judgement in nfs3_async_handle_jukebox
SUNRPC: Tweak TCP socket shutdown in the RPC client
SUNRPC: Simplify socket shutdown when not reusing TCP ports
NFSv4.2: remove restriction of copy size for inter-server copy.
NFS: Clean up the synopsis of callback process_op()
NFS: Extract the xdr_init_encode/decode() calls from decode_compound
NFS: Remove unused callback void decoder
NFS: Add a private local dispatcher for NFSv4 callback operations
SUNRPC: Eliminate the RQ_AUTHERR flag
SUNRPC: Set rq_auth_stat in the pg_authenticate() callout
SUNRPC: Add svc_rqst::rq_auth_stat
SUNRPC: Add dst_port to the sysfs xprt info file
SUNRPC: Add srcaddr as a file in sysfs
sunrpc: Fix return value of get_srcport()
...
Linus Torvalds [Fri, 3 Sep 2021 22:55:41 +0000 (15:55 -0700)]
Merge tag 'linux-kselftest-next-5.15-rc1' of git://git./linux/kernel/git/shuah/linux-kselftest
Pull Kselftest updates from Shuah Khan:
"Fixes to build and test failures:
- openat2 test failure for O_LARGEFILE flag on ARM64
- x86 test build failures related to glibc 2.34 adding support for
variable sized MINSIGSTKSZ and SIGSTKSZ
- removing obsolete configs in sync and cpufreq config files
- minor spelling and duplicate header include cleanups"
* tag 'linux-kselftest-next-5.15-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/shuah/linux-kselftest:
selftests/cpufreq: Rename DEBUG_PI_LIST to DEBUG_PLIST
selftests/sync: Remove the deprecated config SYNC
selftests: safesetid: Fix spelling mistake "cant" -> "can't"
selftests/x86: Fix error: variably modified 'altstack_data' at file scope
kselftest:sched: remove duplicate include in cs_prctl_test.c
selftests: openat2: Fix testing failure for O_LARGEFILE flag
Linus Torvalds [Fri, 3 Sep 2021 22:33:47 +0000 (15:33 -0700)]
Merge tag 'kbuild-v5.15' of git://git./linux/kernel/git/masahiroy/linux-kbuild
Pull Kbuild updates from Masahiro Yamada:
- Add -s option (strict mode) to merge_config.sh to make it fail when
any symbol is redefined.
- Show a warning if a different compiler is used for building external
modules.
- Infer --target from ARCH for CC=clang to let you cross-compile the
kernel without CROSS_COMPILE.
- Make the integrated assembler default (LLVM_IAS=1) for CC=clang.
- Add <linux/stdarg.h> to the kernel source instead of borrowing
<stdarg.h> from the compiler.
- Add Nick Desaulniers as a Kbuild reviewer.
- Drop stale cc-option tests.
- Fix the combination of CONFIG_TRIM_UNUSED_KSYMS and CONFIG_LTO_CLANG
to handle symbols in inline assembly.
- Show a warning if 'FORCE' is missing for if_changed rules.
- Various cleanups
* tag 'kbuild-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild: (39 commits)
kbuild: redo fake deps at include/ksym/*.h
kbuild: clean up objtool_args slightly
modpost: get the *.mod file path more simply
checkkconfigsymbols.py: Fix the '--ignore' option
kbuild: merge vmlinux_link() between ARCH=um and other architectures
kbuild: do not remove 'linux' link in scripts/link-vmlinux.sh
kbuild: merge vmlinux_link() between the ordinary link and Clang LTO
kbuild: remove stale *.symversions
kbuild: remove unused quiet_cmd_update_lto_symversions
gen_compile_commands: extract compiler command from a series of commands
x86: remove cc-option-yn test for -mtune=
arc: replace cc-option-yn uses with cc-option
s390: replace cc-option-yn uses with cc-option
ia64: move core-y in arch/ia64/Makefile to arch/ia64/Kbuild
sparc: move the install rule to arch/sparc/Makefile
security: remove unneeded subdir-$(CONFIG_...)
kbuild: sh: remove unused install script
kbuild: Fix 'no symbols' warning when CONFIG_TRIM_UNUSD_KSYMS=y
kbuild: Switch to 'f' variants of integrated assembler flag
kbuild: Shuffle blank line to improve comment meaning
...
Linus Torvalds [Fri, 3 Sep 2021 22:21:54 +0000 (15:21 -0700)]
Merge branch 'stable/for-linus-5.15-rc0' of git://git./linux/kernel/git/konrad/ibft
Pull ibft fix from Konrad Rzeszutek Wilk:
"An arm64 compile fix for the new code that fixed the iBFT KASLR
handling. I missed the original 0-day build email report"
* 'stable/for-linus-5.15-rc0' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/ibft:
iscsi_ibft: Fix isa_bus_to_virt not working under ARM
Linus Torvalds [Fri, 3 Sep 2021 18:22:50 +0000 (11:22 -0700)]
Merge tag 'powerpc-5.15-1' of git://git./linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Convert pseries & powernv to use MSI IRQ domains.
- Rework the pseries CPU numbering so that CPUs that are removed, and
later re-added, are given a CPU number on the same node as
previously, when possible.
- Add support for a new more flexible device-tree format for specifying
NUMA distances.
- Convert powerpc to GENERIC_PTDUMP.
- Retire sbc8548 and sbc8641d board support.
- Various other small features and fixes.
Thanks to Alexey Kardashevskiy, Aneesh Kumar K.V, Anton Blanchard,
Cédric Le Goater, Christophe Leroy, Emmanuel Gil Peyrot, Fabiano Rosas,
Fangrui Song, Finn Thain, Gautham R. Shenoy, Hari Bathini, Joel
Stanley, Jordan Niethe, Kajol Jain, Laurent Dufour, Leonardo Bras, Lukas
Bulwahn, Marc Zyngier, Masahiro Yamada, Michal Suchanek, Nathan
Chancellor, Nicholas Piggin, Parth Shah, Paul Gortmaker, Pratik R.
Sampat, Randy Dunlap, Sebastian Andrzej Siewior, Srikar Dronamraju, Wan
Jiabing, Xiongwei Song, and Zheng Yongjun.
* tag 'powerpc-5.15-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (154 commits)
powerpc/bug: Cast to unsigned long before passing to inline asm
powerpc/ptdump: Fix generic ptdump for 64-bit
KVM: PPC: Fix clearing never mapped TCEs in realmode
powerpc/pseries/iommu: Rename "direct window" to "dma window"
powerpc/pseries/iommu: Make use of DDW for indirect mapping
powerpc/pseries/iommu: Find existing DDW with given property name
powerpc/pseries/iommu: Update remove_dma_window() to accept property name
powerpc/pseries/iommu: Reorganize iommu_table_setparms*() with new helper
powerpc/pseries/iommu: Add ddw_property_create() and refactor enable_ddw()
powerpc/pseries/iommu: Allow DDW windows starting at 0x00
powerpc/pseries/iommu: Add ddw_list_new_entry() helper
powerpc/pseries/iommu: Add iommu_pseries_alloc_table() helper
powerpc/kernel/iommu: Add new iommu_table_in_use() helper
powerpc/pseries/iommu: Replace hard-coded page shift
powerpc/numa: Update cpu_cpu_map on CPU online/offline
powerpc/numa: Print debug statements only when required
powerpc/numa: convert printk to pr_xxx
powerpc/numa: Drop dbg in favour of pr_debug
powerpc/smp: Enable CACHE domain for shared processor
powerpc/smp: Update cpu_core_map on all PowerPc systems
...
Linus Torvalds [Fri, 3 Sep 2021 18:15:49 +0000 (11:15 -0700)]
Merge tag 'for-5.15/parisc-2' of git://git./linux/kernel/git/deller/parisc-linux
Pull parisc architecture fixes from Helge Deller:
"Fix an unaligned-access crash in the bootloader and drop asm/swab.h"
* tag 'for-5.15/parisc-2' of git://git.kernel.org/pub/scm/linux/kernel/git/deller/parisc-linux:
parisc: Fix unaligned-access crash in bootloader
parisc: Drop __arch_swab16(), arch_swab24(), _arch_swab32() and __arch_swab64() functions
Linus Torvalds [Fri, 3 Sep 2021 18:11:54 +0000 (11:11 -0700)]
Merge tag 'mips_5.15' of git://git./linux/kernel/git/mips/linux
Pull MIPS updates from Thomas Bogendoerfer:
- converted Pistachio platform to use MIPS generic kernel
- fixes and cleanups
* tag 'mips_5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/mips/linux: (29 commits)
MIPS: Malta: fix alignment of the devicetree buffer
MIPS: ingenic: Unconditionally enable clock of CPU #0
MIPS: mscc: ocelot: mark the phy-mode for internal PHY ports
MIPS: mscc: ocelot: disable all switch ports by default
MAINTAINERS: adjust PISTACHIO SOC SUPPORT after its retirement
MIPS: Return true/false (not 1/0) from bool functions
MIPS: generic: Return true/false (not 1/0) from bool functions
MIPS: Make a alias for pistachio_defconfig
MIPS: Retire MACH_PISTACHIO
MIPS: config: generic: Add config for Marduk board
pinctrl: pistachio: Make it as an option
phy: pistachio-usb: Depend on MIPS || COMPILE_TEST
clocksource/drivers/pistachio: Make it selectable for MIPS
clk: pistachio: Make it selectable for generic MIPS kernel
MIPS: DTS: Pistachio add missing cpc and cdmm
MIPS: generic: Allow generating FIT image for Marduk board
MIPS: locking/atomic: Fix atomic{_64,}_sub_if_positive
MIPS: loongson2ef: don't build serial.o unconditionally
MIPS: Replace deprecated CPU-hotplug functions.
MIPS: Alchemy: Fix spelling contraction "cant" -> "can't"
...
Linus Torvalds [Fri, 3 Sep 2021 18:03:00 +0000 (11:03 -0700)]
Merge tag 'for-linus' of git://github.com/openrisc/linux
Pull OpenRISC updates from Stafford Horne:
"A few cleanups and compiler warning fixes for OpenRISC.
Also, this includes dts and defconfig updates to enable Ethernet on
OpenRISC/Litex FPGA SoC's now that the LiteEth driver has gone
upstream"
* tag 'for-linus' of git://github.com/openrisc/linux:
openrisc/litex: Update defconfig
openrisc/litex: Add ethernet device
openrisc/litex: Update uart address
openrisc: Fix compiler warnings in setup
openrisc: rename or32 code & comments to or1k
openrisc: don't printk() unconditionally
Linus Torvalds [Fri, 3 Sep 2021 17:57:25 +0000 (10:57 -0700)]
Merge tag 'livepatching-for-5.15' of git://git./linux/kernel/git/livepatching/livepatching
Pull livepatching update from Petr Mladek.
* tag 'livepatching-for-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/livepatching/livepatching:
livepatch: Replace deprecated CPU-hotplug functions.
Linus Torvalds [Fri, 3 Sep 2021 17:44:35 +0000 (10:44 -0700)]
Merge tag 'iommu-updates-v5.15' of git://git./linux/kernel/git/joro/iommu
Pull iommu updates from Joerg Roedel:
- New DART IOMMU driver for Apple Silicon M1 chips
- Optimizations for iommu_[map/unmap] performance
- Selective TLB flush support for the AMD IOMMU driver to make it more
efficient on emulated IOMMUs
- Rework IOVA setup and default domain type setting to move more code
out of IOMMU drivers and to support runtime switching between certain
types of default domains
- VT-d Updates from Lu Baolu:
- Update the virtual command related registers
- Enable Intel IOMMU scalable mode by default
- Preset A/D bits for user space DMA usage
- Allow devices to have more than 32 outstanding PRs
- Various cleanups
- ARM SMMU Updates from Will Deacon:
SMMUv3:
- Minor optimisation to avoid zeroing struct members on CMD submission
- Increased use of batched commands to reduce submission latency
- Refactoring in preparation for ECMDQ support
SMMUv2:
- Fix races when probing devices with identical StreamIDs
- Optimise walk cache flushing for Qualcomm implementations
- Allow deep sleep states for some Qualcomm SoCs with shared clocks
- Various smaller optimizations, cleanups, and fixes
* tag 'iommu-updates-v5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/joro/iommu: (85 commits)
iommu/io-pgtable: Abstract iommu_iotlb_gather access
iommu/arm-smmu: Fix missing unlock on error in arm_smmu_device_group()
iommu/vt-d: Add present bit check in pasid entry setup helpers
iommu/vt-d: Use pasid_pte_is_present() helper function
iommu/vt-d: Drop the kernel doc annotation
iommu/vt-d: Allow devices to have more than 32 outstanding PRs
iommu/vt-d: Preset A/D bits for user space DMA usage
iommu/vt-d: Enable Intel IOMMU scalable mode by default
iommu/vt-d: Refactor Kconfig a bit
iommu/vt-d: Remove unnecessary oom message
iommu/vt-d: Update the virtual command related registers
iommu: Allow enabling non-strict mode dynamically
iommu: Merge strictness and domain type configs
iommu: Only log strictness for DMA domains
iommu: Expose DMA domain strictness via sysfs
iommu: Express DMA strictness via the domain type
iommu/vt-d: Prepare for multiple DMA domain types
iommu/arm-smmu: Prepare for multiple DMA domain types
iommu/amd: Prepare for multiple DMA domain types
iommu: Introduce explicit type for non-strict DMA domains
...
Linus Torvalds [Fri, 3 Sep 2021 17:34:44 +0000 (10:34 -0700)]
Merge branch 'stable/for-linus-5.15' of git://git./linux/kernel/git/konrad/swiotlb
Pull swiotlb updates from Konrad Rzeszutek Wilk:
"A new feature called restricted DMA pools. It allows SWIOTLB to
utilize per-device (or per-platform) allocated memory pools instead of
using the global one.
The first big user of this is ARM Confidential Computing where the
memory for DMA operations can be set per platform"
* 'stable/for-linus-5.15' of git://git.kernel.org/pub/scm/linux/kernel/git/konrad/swiotlb: (23 commits)
swiotlb: use depends on for DMA_RESTRICTED_POOL
of: restricted dma: Don't fail device probe on rmem init failure
of: Move of_dma_set_restricted_buffer() into device.c
powerpc/svm: Don't issue ultracalls if !mem_encrypt_active()
s390/pv: fix the forcing of the swiotlb
swiotlb: Free tbl memory in swiotlb_exit()
swiotlb: Emit diagnostic in swiotlb_exit()
swiotlb: Convert io_default_tlb_mem to static allocation
of: Return success from of_dma_set_restricted_buffer() when !OF_ADDRESS
swiotlb: add overflow checks to swiotlb_bounce
swiotlb: fix implicit debugfs declarations
of: Add plumbing for restricted DMA pool
dt-bindings: of: Add restricted DMA pool
swiotlb: Add restricted DMA pool initialization
swiotlb: Add restricted DMA alloc/free support
swiotlb: Refactor swiotlb_tbl_unmap_single
swiotlb: Move alloc_size to swiotlb_find_slots
swiotlb: Use is_swiotlb_force_bounce for swiotlb data bouncing
swiotlb: Update is_swiotlb_active to add a struct device argument
swiotlb: Update is_swiotlb_buffer to add a struct device argument
...
Linus Torvalds [Fri, 3 Sep 2021 17:08:28 +0000 (10:08 -0700)]
Merge branch 'akpm' (patches from Andrew)
Merge misc updates from Andrew Morton:
"173 patches.
Subsystems affected by this series: ia64, ocfs2, block, and mm (debug,
pagecache, gup, swap, shmem, memcg, selftests, pagemap, mremap,
bootmem, sparsemem, vmalloc, kasan, pagealloc, memory-failure,
hugetlb, userfaultfd, vmscan, compaction, mempolicy, memblock,
oom-kill, migration, ksm, percpu, vmstat, and madvise)"
* emailed patches from Andrew Morton <akpm@linux-foundation.org>: (173 commits)
mm/madvise: add MADV_WILLNEED to process_madvise()
mm/vmstat: remove unneeded return value
mm/vmstat: simplify the array size calculation
mm/vmstat: correct some wrong comments
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
selftests: vm: add COW time test for KSM pages
selftests: vm: add KSM merging time test
mm: KSM: fix data type
selftests: vm: add KSM merging across nodes test
selftests: vm: add KSM zero page merging test
selftests: vm: add KSM unmerge test
selftests: vm: add KSM merge test
mm/migrate: correct kernel-doc notation
mm: wire up syscall process_mrelease
mm: introduce process_mrelease system call
memblock: make memblock_find_in_range method private
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
...
zhangkui [Thu, 2 Sep 2021 22:01:11 +0000 (15:01 -0700)]
mm/madvise: add MADV_WILLNEED to process_madvise()
There is a usecase in Android that an app process's memory is swapped out
by process_madvise() with MADV_PAGEOUT, such as the memory is swapped to
zram or a backing device. When the process is scheduled to running, like
switch to foreground, multiple page faults may cause the app dropped
frames.
To reduce the problem, System Management Software can read-ahead memory
of the process immediately when the app switches to forground. Calling
process_madvise() with MADV_WILLNEED can meet this need.
Link: https://lkml.kernel.org/r/20210804082010.12482-1-zhangkui@oppo.com
Signed-off-by: zhangkui <zhangkui@oppo.com>
Cc: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miaohe Lin [Thu, 2 Sep 2021 22:01:08 +0000 (15:01 -0700)]
mm/vmstat: remove unneeded return value
The return value of pagetypeinfo_showfree and pagetypeinfo_showblockcount
are unused now. Remove them.
Link: https://lkml.kernel.org/r/20210715122911.15700-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miaohe Lin [Thu, 2 Sep 2021 22:01:05 +0000 (15:01 -0700)]
mm/vmstat: simplify the array size calculation
We can replace the array_num * sizeof(array[0]) with sizeof(array) to
simplify the code.
Link: https://lkml.kernel.org/r/20210715122911.15700-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miaohe Lin [Thu, 2 Sep 2021 22:01:03 +0000 (15:01 -0700)]
mm/vmstat: correct some wrong comments
Patch series "Cleanup for vmstat".
This series contains cleanups to remove unneeded return value, correct
wrong comment and simplify the array size calculation. More details can
be found in the respective changelogs.
This patch (of 3):
Correct wrong fls(mem+1) to fls(mem)+1 and remove the duplicated comment
with quiet_vmstat().
Link: https://lkml.kernel.org/r/20210715122911.15700-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20210715122911.15700-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jing Xiangfeng [Thu, 2 Sep 2021 22:01:00 +0000 (15:01 -0700)]
mm/percpu,c: remove obsolete comments of pcpu_chunk_populated()
Commit
b239f7daf553 ("percpu: set PCPU_BITMAP_BLOCK_SIZE to PAGE_SIZE")
removed the parameter 'for_alloc', so remove this comment.
Link: https://lkml.kernel.org/r/1630576043-21367-1-git-send-email-jingxiangfeng@huawei.com
Signed-off-by: Jing Xiangfeng <jingxiangfeng@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhansaya Bagdauletkyzy [Thu, 2 Sep 2021 22:00:57 +0000 (15:00 -0700)]
selftests: vm: add COW time test for KSM pages
Since merged pages are copied every time they need to be modified, the
write access time is different between shared and non-shared pages. Add
ksm_cow_time() function which evaluates latency of these COW breaks.
First, 4000 pages are allocated and the time, required to modify 1 byte in
every other page, is measured. After this, the pages are merged into 2000
pairs and in each pair, 1 page is modified (i.e. they are decoupled) to
detect COW breaks. The time needed to break COW of merged pages is then
compared with performance of non-shared pages.
The test is run as follows: ./ksm_tests -C
The output:
Total size: 15 MiB
Not merged pages:
Total time: 0.
002185489 s
Average speed: 3202.945 MiB/s
Merged pages:
Total time: 0.
004386872 s
Average speed: 1595.670 MiB/s
Link: https://lkml.kernel.org/r/1d03ee0d1b341959d4b61672c6401d498bff5652.1629386192.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhansaya Bagdauletkyzy [Thu, 2 Sep 2021 22:00:54 +0000 (15:00 -0700)]
selftests: vm: add KSM merging time test
Patch series "add KSM performance tests", v3.
Extend KSM self tests with a performance benchmark. These tests are not
part of regular regression testing, as they are mainly intended to be used
by developers making changes to the memory management subsystem.
This patch (of 2):
Add ksm_merge_time() function to determine speed and time needed for
merging. The total spent time is shown in seconds while speed is in
MiB/s. User must specify the size of duplicated memory area (in MiB)
before running the test.
The test is run as follows: ./ksm_tests -P -s 100
The output:
Total size: 100 MiB
Total time: 0.
201106786 s
Average speed: 497.248 MiB/s
Link: https://lkml.kernel.org/r/cover.1629386192.git.zhansayabagdaulet@gmail.com
Link: https://lkml.kernel.org/r/318b946ac80cc9205c89d0962048378f7ce0705b.1629386192.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhansaya Bagdauletkyzy [Thu, 2 Sep 2021 22:00:51 +0000 (15:00 -0700)]
mm: KSM: fix data type
ksm_stable_node_chains_prune_millisecs is declared as int, but in
stable__node_chains_prune_millisecs_store(), it can store values up to
UINT_MAX. Change its type to unsigned int.
Link: https://lkml.kernel.org/r/20210806111351.GA71845@asus
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhansaya Bagdauletkyzy [Thu, 2 Sep 2021 22:00:48 +0000 (15:00 -0700)]
selftests: vm: add KSM merging across nodes test
Add check_ksm_numa_merge() function to test that pages in different NUMA
nodes are being handled properly. First, two duplicate pages are
allocated in two separate NUMA nodes using the libnuma library. Since
there is one unique page in each node, with merge_across_nodes = 0, there
won't be any shared pages. If merge_across_nodes is set to 1, the pages
will be treated as usual duplicate pages and will be merged. If NUMA
config is not enabled or the number of NUMA nodes is less than two, then
the test is skipped. The test is run as follows: ./ksm_tests -N
Link: https://lkml.kernel.org/r/071c17b5b04ebb0dfeba137acc495e5dd9d2a719.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhansaya Bagdauletkyzy [Thu, 2 Sep 2021 22:00:45 +0000 (15:00 -0700)]
selftests: vm: add KSM zero page merging test
Add check_ksm_zero_page_merge() function to test that empty pages are
being handled properly. For this, several zero pages are allocated and
merged using madvise. If use_zero_pages is enabled, the pages must be
shared with the special kernel zero pages; otherwise, they are merged as
usual duplicate pages. The test is run as follows: ./ksm_tests -Z
Link: https://lkml.kernel.org/r/6d0caab00d4bdccf5e3791cb95cf6dfd5eb85e45.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhansaya Bagdauletkyzy [Thu, 2 Sep 2021 22:00:42 +0000 (15:00 -0700)]
selftests: vm: add KSM unmerge test
Add check_ksm_unmerge() function to verify that KSM is properly unmerging
shared pages. For this, two duplicate pages are merged first and then
their contents are modified. Since they are not identical anymore, the
pages must be unmerged and the number of merged pages has to be 0. The
test is run as follows: ./ksm_tests -U
Link: https://lkml.kernel.org/r/c0f55420440d704d5b094275b4365aa1b2ad46b5.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Shuah Khan <shuah@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Zhansaya Bagdauletkyzy [Thu, 2 Sep 2021 22:00:39 +0000 (15:00 -0700)]
selftests: vm: add KSM merge test
Patch series "add KSM selftests".
Introduce selftests to validate the functionality of KSM. The tests are
run on private anonymous pages. Since some KSM tunables are modified,
their starting values are saved and restored after testing. At the start,
run is set to 2 to ensure that only test pages will be merged (we assume
that no applications make madvise syscalls in the background). If KSM
config not enabled, all tests will be skipped.
This patch (of 4):
Add check_ksm_merge() function to check the basic merging feature of KSM.
First, some number of identical pages are allocated and the MADV_MERGEABLE
advice is given to merge these pages. Then, pages_shared and
pages_sharing values are compared with the expected numbers using
assert_ksm_pages_count() function. The number of pages can be changed
using -p option.
Link: https://lkml.kernel.org/r/cover.1626252248.git.zhansayabagdaulet@gmail.com
Link: https://lkml.kernel.org/r/90287685c13300972ea84de93d1f3f900373f9fe.1626252248.git.zhansayabagdaulet@gmail.com
Signed-off-by: Zhansaya Bagdauletkyzy <zhansayabagdaulet@gmail.com>
Reviewed-by: Pavel Tatashin <pasha.tatashin@soleen.com>
Reviewed-by: Tyler Hicks <tyhicks@linux.microsoft.com>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Randy Dunlap [Thu, 2 Sep 2021 22:00:36 +0000 (15:00 -0700)]
mm/migrate: correct kernel-doc notation
Use the expected "Return:" format to prevent a kernel-doc warning.
mm/migrate.c:1157: warning: Excess function parameter 'returns' description in 'next_demotion_node'
Link: https://lkml.kernel.org/r/20210808203151.10632-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Suren Baghdasaryan [Thu, 2 Sep 2021 22:00:33 +0000 (15:00 -0700)]
mm: wire up syscall process_mrelease
Split off from prev patch in the series that implements the syscall.
Link: https://lkml.kernel.org/r/20210809185259.405936-2-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Acked-by: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Jan Engelhardt <jengelh@inai.de>
Cc: Jann Horn <jannh@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Shakeel Butt <shakeelb@google.com>
Cc: Tim Murray <timmurray@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Suren Baghdasaryan [Thu, 2 Sep 2021 22:00:29 +0000 (15:00 -0700)]
mm: introduce process_mrelease system call
In modern systems it's not unusual to have a system component monitoring
memory conditions of the system and tasked with keeping system memory
pressure under control. One way to accomplish that is to kill
non-essential processes to free up memory for more important ones.
Examples of this are Facebook's OOM killer daemon called oomd and
Android's low memory killer daemon called lmkd.
For such system component it's important to be able to free memory quickly
and efficiently. Unfortunately the time process takes to free up its
memory after receiving a SIGKILL might vary based on the state of the
process (uninterruptible sleep), size and OPP level of the core the
process is running. A mechanism to free resources of the target process
in a more predictable way would improve system's ability to control its
memory pressure.
Introduce process_mrelease system call that releases memory of a dying
process from the context of the caller. This way the memory is freed in a
more controllable way with CPU affinity and priority of the caller. The
workload of freeing the memory will also be charged to the caller. The
operation is allowed only on a dying process.
After previous discussions [1, 2, 3] the decision was made [4] to
introduce a dedicated system call to cover this use case.
The API is as follows,
int process_mrelease(int pidfd, unsigned int flags);
DESCRIPTION
The process_mrelease() system call is used to free the memory of
an exiting process.
The pidfd selects the process referred to by the PID file
descriptor.
(See pidfd_open(2) for further information)
The flags argument is reserved for future use; currently, this
argument must be specified as 0.
RETURN VALUE
On success, process_mrelease() returns 0. On error, -1 is
returned and errno is set to indicate the error.
ERRORS
EBADF pidfd is not a valid PID file descriptor.
EAGAIN Failed to release part of the address space.
EINTR The call was interrupted by a signal; see signal(7).
EINVAL flags is not 0.
EINVAL The memory of the task cannot be released because the
process is not exiting, the address space is shared
with another live process or there is a core dump in
progress.
ENOSYS This system call is not supported, for example, without
MMU support built into Linux.
ESRCH The target process does not exist (i.e., it has terminated
and been waited on).
[1] https://lore.kernel.org/lkml/
20190411014353.113252-3-surenb@google.com/
[2] https://lore.kernel.org/linux-api/
20201113173448.1863419-1-surenb@google.com/
[3] https://lore.kernel.org/linux-api/
20201124053943.1684874-3-surenb@google.com/
[4] https://lore.kernel.org/linux-api/
20201223075712.GA4719@lst.de/
Link: https://lkml.kernel.org/r/20210809185259.405936-1-surenb@google.com
Signed-off-by: Suren Baghdasaryan <surenb@google.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: David Hildenbrand <david@redhat.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Christian Brauner <christian.brauner@ubuntu.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Matthew Wilcox (Oracle) <willy@infradead.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Roman Gushchin <guro@fb.com>
Cc: Rik van Riel <riel@surriel.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Jann Horn <jannh@google.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Florian Weimer <fweimer@redhat.com>
Cc: Jan Engelhardt <jengelh@inai.de>
Cc: Tim Murray <timmurray@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike Rapoport [Thu, 2 Sep 2021 22:00:26 +0000 (15:00 -0700)]
memblock: make memblock_find_in_range method private
There are a lot of uses of memblock_find_in_range() along with
memblock_reserve() from the times memblock allocation APIs did not exist.
memblock_find_in_range() is the very core of memblock allocations, so any
future changes to its internal behaviour would mandate updates of all the
users outside memblock.
Replace the calls to memblock_find_in_range() with an equivalent calls to
memblock_phys_alloc() and memblock_phys_alloc_range() and make
memblock_find_in_range() private method of memblock.
This simplifies the callers, ensures that (unlikely) errors in
memblock_reserve() are handled and improves maintainability of
memblock_find_in_range().
Link: https://lkml.kernel.org/r/20210816122622.30279-1-rppt@kernel.org
Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com> [arm64]
Acked-by: Kirill A. Shutemov <kirill.shtuemov@linux.intel.com>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> [ACPI]
Acked-by: Russell King (Oracle) <rmk+kernel@armlinux.org.uk>
Acked-by: Nick Kossifidis <mick@ics.forth.gr> [riscv]
Tested-by: Guenter Roeck <linux@roeck-us.net>
Acked-by: Rob Herring <robh@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vasily Averin [Thu, 2 Sep 2021 22:00:23 +0000 (15:00 -0700)]
mm/mempolicy.c: use in_task() in mempolicy_slab_node()
Obsoleted in_intrrupt() include task context with disabled BH, it's better
to use in_task() instead.
Link: https://lkml.kernel.org/r/984ee771-4834-21da-801f-c15c18ddf4d1@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Feng Tang [Thu, 2 Sep 2021 22:00:19 +0000 (15:00 -0700)]
mm/mempolicy: unify the create() func for bind/interleave/prefer-many policies
As they all do the same thing: sanity check and save nodemask info, create
one mpol_new_nodemask() to reduce redundancy.
Link: https://lkml.kernel.org/r/1627970362-61305-6-git-send-email-feng.tang@intel.com
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Ben Widawsky <ben.widawsky@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ben Widawsky [Thu, 2 Sep 2021 22:00:16 +0000 (15:00 -0700)]
mm/mempolicy: advertise new MPOL_PREFERRED_MANY
Adds a new mode to the existing mempolicy modes, MPOL_PREFERRED_MANY.
MPOL_PREFERRED_MANY will be adequately documented in the internal
admin-guide with this patch. Eventually, the man pages for mbind(2),
get_mempolicy(2), set_mempolicy(2) and numactl(8) will also have text
about this mode. Those shall contain the canonical reference.
NUMA systems continue to become more prevalent. New technologies like
PMEM make finer grain control over memory access patterns increasingly
desirable. MPOL_PREFERRED_MANY allows userspace to specify a set of nodes
that will be tried first when performing allocations. If those
allocations fail, all remaining nodes will be tried. It's a straight
forward API which solves many of the presumptive needs of system
administrators wanting to optimize workloads on such machines. The mode
will work either per VMA, or per thread.
[Michal Hocko: refine kernel doc for MPOL_PREFERRED_MANY]
Link: https://lore.kernel.org/r/20200630212517.308045-13-ben.widawsky@intel.com
Link: https://lkml.kernel.org/r/1627970362-61305-5-git-send-email-feng.tang@intel.com
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Ben Widawsky [Thu, 2 Sep 2021 22:00:13 +0000 (15:00 -0700)]
mm/hugetlb: add support for mempolicy MPOL_PREFERRED_MANY
Implement the missing huge page allocation functionality while obeying the
preferred node semantics. This is similar to the implementation for
general page allocation, as it uses a fallback mechanism to try multiple
preferred nodes first, and then all other nodes.
To avoid adding too many "#ifdef CONFIG_NUMA" check, add a helper function
in mempolicy.h to check whether a mempolicy is MPOL_PREFERRED_MANY.
[akpm@linux-foundation.org: fix compiling issue when merging with other hugetlb patch]
[Thanks to 0day bot for catching the !CONFIG_NUMA compiling issue]
[mhocko@suse.com: suggest to remove the #ifdef CONFIG_NUMA check]
[ben.widawsky@intel.com: add helpers to avoid ifdefs]
Link: https://lore.kernel.org/r/20200630212517.308045-12-ben.widawsky@intel.com
Link: https://lkml.kernel.org/r/1627970362-61305-4-git-send-email-feng.tang@intel.com
Link: https://lkml.kernel.org/r/20210809024430.GA46432@shbuild999.sh.intel.com
[nathan@kernel.org: initialize page to NULL in alloc_buddy_huge_page_with_mpol()]
Link: https://lkml.kernel.org/r/20210810200632.3812797-1-nathan@kernel.org
Link: https://lore.kernel.org/r/20200630212517.308045-12-ben.widawsky@intel.com
Link: https://lkml.kernel.org/r/1627970362-61305-4-git-send-email-feng.tang@intel.com
Link: https://lkml.kernel.org/r/20210809024430.GA46432@shbuild999.sh.intel.com
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Co-developed-by: Feng Tang <feng.tang@intel.com>
Suggested-by: Michal Hocko <mhocko@suse.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Feng Tang [Thu, 2 Sep 2021 22:00:10 +0000 (15:00 -0700)]
mm/memplicy: add page allocation function for MPOL_PREFERRED_MANY policy
The semantics of MPOL_PREFERRED_MANY is similar to MPOL_PREFERRED, that it
will first try to allocate memory from the preferred node(s), and fallback
to all nodes in system when first try fails.
Add a dedicated function alloc_pages_preferred_many() for it just like for
'interleave' policy, which will be used by 2 general memoory allocation
APIs: alloc_pages() and alloc_pages_vma()
Link: https://lore.kernel.org/r/20200630212517.308045-9-ben.widawsky@intel.com
Link: https://lkml.kernel.org/r/1627970362-61305-3-git-send-email-feng.tang@intel.com
Suggested-by: Michal Hocko <mhocko@suse.com>
Originally-by: Ben Widawsky <ben.widawsky@intel.com>
Co-developed-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Huang Ying <ying.huang@intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen [Thu, 2 Sep 2021 22:00:06 +0000 (15:00 -0700)]
mm/mempolicy: add MPOL_PREFERRED_MANY for multiple preferred nodes
Patch series "Introduce multi-preference mempolicy", v7.
This patch series introduces the concept of the MPOL_PREFERRED_MANY
mempolicy. This mempolicy mode can be used with either the
set_mempolicy(2) or mbind(2) interfaces. Like the MPOL_PREFERRED
interface, it allows an application to set a preference for nodes which
will fulfil memory allocation requests. Unlike the MPOL_PREFERRED mode,
it takes a set of nodes. Like the MPOL_BIND interface, it works over a
set of nodes. Unlike MPOL_BIND, it will not cause a SIGSEGV or invoke the
OOM killer if those preferred nodes are not available.
Along with these patches are patches for libnuma, numactl, numademo, and
memhog. They still need some polish, but can be found here:
https://gitlab.com/bwidawsk/numactl/-/tree/prefer-many It allows new
usage: `numactl -P 0,3,4`
The goal of the new mode is to enable some use-cases when using tiered memory
usage models which I've lovingly named.
1a. The Hare - The interconnect is fast enough to meet bandwidth and
latency requirements allowing preference to be given to all nodes with
"fast" memory.
1b. The Indiscriminate Hare - An application knows it wants fast
memory (or perhaps slow memory), but doesn't care which node it runs
on. The application can prefer a set of nodes and then xpu bind to
the local node (cpu, accelerator, etc). This reverses the nodes are
chosen today where the kernel attempts to use local memory to the CPU
whenever possible. This will attempt to use the local accelerator to
the memory.
2. The Tortoise - The administrator (or the application itself) is
aware it only needs slow memory, and so can prefer that.
Much of this is almost achievable with the bind interface, but the bind
interface suffers from an inability to fallback to another set of nodes if
binding fails to all nodes in the nodemask.
Like MPOL_BIND a nodemask is given. Inherently this removes ordering from the
preference.
> /* Set first two nodes as preferred in an 8 node system. */
> const unsigned long nodes = 0x3
> set_mempolicy(MPOL_PREFER_MANY, &nodes, 8);
> /* Mimic interleave policy, but have fallback *.
> const unsigned long nodes = 0xaa
> set_mempolicy(MPOL_PREFER_MANY, &nodes, 8);
Some internal discussion took place around the interface. There are two
alternatives which we have discussed, plus one I stuck in:
1. Ordered list of nodes. Currently it's believed that the added
complexity is nod needed for expected usecases.
2. A flag for bind to allow falling back to other nodes. This
confuses the notion of binding and is less flexible than the current
solution.
3. Create flags or new modes that helps with some ordering. This
offers both a friendlier API as well as a solution for more customized
usage. It's unknown if it's worth the complexity to support this.
Here is sample code for how this might work:
> // Prefer specific nodes for some something wacky
> set_mempolicy(MPOL_PREFER_MANY, 0x17c, 1024);
>
> // Default
> set_mempolicy(MPOL_PREFER_MANY | MPOL_F_PREFER_ORDER_SOCKET, NULL, 0);
> // which is the same as
> set_mempolicy(MPOL_DEFAULT, NULL, 0);
>
> // The Hare
> set_mempolicy(MPOL_PREFER_MANY | MPOL_F_PREFER_ORDER_TYPE, NULL, 0);
>
> // The Tortoise
> set_mempolicy(MPOL_PREFER_MANY | MPOL_F_PREFER_ORDER_TYPE_REV, NULL, 0);
>
> // Prefer the fast memory of the first two sockets
> set_mempolicy(MPOL_PREFER_MANY | MPOL_F_PREFER_ORDER_TYPE, -1, 2);
>
This patch (of 5):
The NUMA APIs currently allow passing in a "preferred node" as a single
bit set in a nodemask. If more than one bit it set, bits after the first
are ignored.
This single node is generally OK for location-based NUMA where memory
being allocated will eventually be operated on by a single CPU. However,
in systems with multiple memory types, folks want to target a *type* of
memory instead of a location. For instance, someone might want some
high-bandwidth memory but do not care about the CPU next to which it is
allocated. Or, they want a cheap, high capacity allocation and want to
target all NUMA nodes which have persistent memory in volatile mode. In
both of these cases, the application wants to target a *set* of nodes, but
does not want strict MPOL_BIND behavior as that could lead to OOM killer
or SIGSEGV.
So add MPOL_PREFERRED_MANY policy to support the multiple preferred nodes
requirement. This is not a pie-in-the-sky dream for an API. This was a
response to a specific ask of more than one group at Intel. Specifically:
1. There are existing libraries that target memory types such as
https://github.com/memkind/memkind. These are known to suffer from
SIGSEGV's when memory is low on targeted memory "kinds" that span more
than one node. The MCDRAM on a Xeon Phi in "Cluster on Die" mode is an
example of this.
2. Volatile-use persistent memory users want to have a memory policy
which is targeted at either "cheap and slow" (PMEM) or "expensive and
fast" (DRAM). However, they do not want to experience allocation
failures when the targeted type is unavailable.
3. Allocate-then-run. Generally, we let the process scheduler decide
on which physical CPU to run a task. That location provides a default
allocation policy, and memory availability is not generally considered
when placing tasks. For situations where memory is valuable and
constrained, some users want to allocate memory first, *then* allocate
close compute resources to the allocation. This is the reverse of the
normal (CPU) model. Accelerators such as GPUs that operate on
core-mm-managed memory are interested in this model.
A check is added in sanitize_mpol_flags() to not permit 'prefer_many'
policy to be used for now, and will be removed in later patch after all
implementations for 'prefer_many' are ready, as suggested by Michal Hocko.
[mhocko@kernel.org: suggest to refine policy_node/policy_nodemask handling]
Link: https://lkml.kernel.org/r/1627970362-61305-1-git-send-email-feng.tang@intel.com
Link: https://lore.kernel.org/r/20200630212517.308045-4-ben.widawsky@intel.com
Link: https://lkml.kernel.org/r/1627970362-61305-2-git-send-email-feng.tang@intel.com
Co-developed-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Ben Widawsky <ben.widawsky@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: Feng Tang <feng.tang@intel.com>
Cc: Michal Hocko <mhocko@kernel.org>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Randy Dunlap <rdunlap@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Huang Ying <ying.huang@intel.com>b
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Baolin Wang [Thu, 2 Sep 2021 22:00:03 +0000 (15:00 -0700)]
mm/mempolicy: use readable NUMA_NO_NODE macro instead of magic number
The caller of mpol_misplaced() already use NUMA_NO_NODE to check whether
current page node is misplaced, thus using NUMA_NO_NODE in
mpol_misplaced() instead of magic number is more readable.
Link: https://lkml.kernel.org/r/1b77c0ce21183fa86f4db250b115cf5e27396528.1627558356.git.baolin.wang@linux.alibaba.com
Signed-off-by: Baolin Wang <baolin.wang@linux.alibaba.com>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Charan Teja Reddy [Thu, 2 Sep 2021 21:59:59 +0000 (14:59 -0700)]
mm: compaction: support triggering of proactive compaction by user
The proactive compaction[1] gets triggered for every 500msec and run
compaction on the node for COMPACTION_HPAGE_ORDER (usually order-9) pages
based on the value set to sysctl.compaction_proactiveness. Triggering the
compaction for every 500msec in search of COMPACTION_HPAGE_ORDER pages is
not needed for all applications, especially on the embedded system
usecases which may have few MB's of RAM. Enabling the proactive
compaction in its state will endup in running almost always on such
systems.
Other side, proactive compaction can still be very much useful for getting
a set of higher order pages in some controllable manner(controlled by
using the sysctl.compaction_proactiveness). So, on systems where enabling
the proactive compaction always may proove not required, can trigger the
same from user space on write to its sysctl interface. As an example, say
app launcher decide to launch the memory heavy application which can be
launched fast if it gets more higher order pages thus launcher can prepare
the system in advance by triggering the proactive compaction from
userspace.
This triggering of proactive compaction is done on a write to
sysctl.compaction_proactiveness by user.
[1]https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit?id=
facdaa917c4d5a376d09d25865f5a863f906234a
[akpm@linux-foundation.org: tweak vm.rst, per Mike]
Link: https://lkml.kernel.org/r/1627653207-12317-1-git-send-email-charante@codeaurora.org
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Acked-by: Rafael Aquini <aquini@redhat.com>
Cc: Mike Rapoport <rppt@kernel.org>
Cc: Luis Chamberlain <mcgrof@kernel.org>
Cc: Kees Cook <keescook@chromium.org>
Cc: Iurii Zaikin <yzaikin@google.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Mel Gorman <mgorman@techsingularity.net>
Cc: Nitin Gupta <nigupta@nvidia.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Khalid Aziz <khalid.aziz@oracle.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Charan Teja Reddy [Thu, 2 Sep 2021 21:59:56 +0000 (14:59 -0700)]
mm: compaction: optimize proactive compaction deferrals
Vlastimil Babka figured out that when fragmentation score didn't go down
across the proactive compaction i.e. when no progress is made, next wake
up for proactive compaction is deferred for 1 << COMPACT_MAX_DEFER_SHIFT,
i.e. 64 times, with each wakeup interval of
HPAGE_FRAG_CHECK_INTERVAL_MSEC(=500). In each of this wakeup, it just
decrement 'proactive_defer' counter and goes sleep i.e. it is getting
woken to just decrement a counter.
The same deferral time can also achieved by simply doing the
HPAGE_FRAG_CHECK_INTERVAL_MSEC << COMPACT_MAX_DEFER_SHIFT thus unnecessary
wakeup of kcompact thread is avoided thus also removes the need of
'proactive_defer' thread counter.
[akpm@linux-foundation.org: tweak comment]
Link: https://lore.kernel.org/linux-fsdevel/88abfdb6-2c13-b5a6-5b46-742d12d1c910@suse.cz/
Link: https://lkml.kernel.org/r/1626869599-25412-1-git-send-email-charante@codeaurora.org
Signed-off-by: Charan Teja Reddy <charante@codeaurora.org>
Acked-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Khalid Aziz <khalid.aziz@oracle.com>
Acked-by: David Rientjes <rientjes@google.com>
Cc: Nitin Gupta <nigupta@nvidia.com>
Cc: Vinayak Menon <vinmenon@codeaurora.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Vlastimil Babka [Thu, 2 Sep 2021 21:59:53 +0000 (14:59 -0700)]
mm, vmscan: guarantee drop_slab_node() termination
drop_slab_node() is called as part of echo 2>/proc/sys/vm/drop_caches
operation. It iterates over all memcgs and calls shrink_slab() which in
turn iterates over all slab shrinkers. Freed objects are counted and as
long as the total number of freed objects from all memcgs and shrinkers is
higher than 10, drop_slab_node() loops for another full memcgs*shrinkers
iteration.
This arbitrary constant threshold of 10 can result in effectively an
infinite loop on a system with large number of memcgs and/or parallel
activity that allocates new objects. This has been reported previously by
Chunxin Zang [1] and recently by our customer.
The previous report [1] has resulted in commit
069c411de40a ("mm/vmscan:
fix infinite loop in drop_slab_node") which added a check for signals
allowing the user to terminate the command writing to drop_caches. At the
time it was also considered to make the threshold grow with each iteration
to guarantee termination, but such patch hasn't been formally proposed
yet.
This patch implements the dynamically growing threshold. At first
iteration it's enough to free one object to continue, and this threshold
effectively doubles with each iteration. Our customer's feedback was
positive.
There is always a risk that this change will result on some system in a
previously terminating drop_caches operation to terminate sooner and free
fewer objects. Ideally the semantics would guarantee freeing all freeable
objects that existed at the moment of starting the operation, while not
looping forever for newly allocated objects, but that's not feasible to
track. In the less ideal solution based on thresholds, arguably the
termination guarantee is more important than the exhaustiveness guarantee.
If there are reports of large regression wrt being exhaustive, we can
tune how fast the threshold grows.
[1] https://lore.kernel.org/lkml/
20200909152047.27905-1-zangchunxin@bytedance.com/T/#u
[vbabka@suse.cz: avoid undefined shift behaviour]
Link: https://lkml.kernel.org/r/2f034e6f-a753-550a-f374-e4e23899d3d5@suse.cz
Link: https://lkml.kernel.org/r/20210818152239.25502-1-vbabka@suse.cz
Signed-off-by: Vlastimil Babka <vbabka@suse.cz>
Reported-by: Chunxin Zang <zangchunxin@bytedance.com>
Cc: Muchun Song <songmuchun@bytedance.com>
Cc: Chris Down <chris@chrisdown.name>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miaohe Lin [Thu, 2 Sep 2021 21:59:50 +0000 (14:59 -0700)]
mm/vmscan: add 'else' to remove check_pending label
We could add 'else' to remove the somewhat odd check_pending label to make
code core succinct.
Link: https://lkml.kernel.org/r/20210717065911.61497-5-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shaohua Li <shli@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miaohe Lin [Thu, 2 Sep 2021 21:59:46 +0000 (14:59 -0700)]
mm/vmscan: remove unneeded return value of kswapd_run()
The return value of kswapd_run() is unused now. Clean it up.
Link: https://lkml.kernel.org/r/20210717065911.61497-4-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shaohua Li <shli@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miaohe Lin [Thu, 2 Sep 2021 21:59:43 +0000 (14:59 -0700)]
mm/vmscan: remove misleading setting to sc->priority
The priority field of sc is used to control how many pages we should scan
at once while we always traverse the list to shrink the pages in these
functions. So these settings are unneeded and misleading.
Link: https://lkml.kernel.org/r/20210717065911.61497-3-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Shaohua Li <shli@fb.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Yu Zhao <yuzhao@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Miaohe Lin [Thu, 2 Sep 2021 21:59:39 +0000 (14:59 -0700)]
mm/vmscan: remove the PageDirty check after MADV_FREE pages are page_ref_freezed
Patch series "Cleanups for vmscan", v2.
This series contains cleanups to remove unneeded return value, misleading
setting and so on. Also this remove the PageDirty check after MADV_FREE
pages are page_ref_freezed. More details can be found in the respective
changelogs.
This patch (of 4):
If the MADV_FREE pages are redirtied before they could be reclaimed, put
the pages back to anonymous LRU list by setting SwapBacked flag and the
pages will be reclaimed in normal swapout way. But as Yu Zhao pointed
out, "The page has only one reference left, which is from the isolation.
After the caller puts the page back on lru and drops the reference, the
page will be freed anyway. It doesn't matter which lru it goes." So we
don't bother checking PageDirty here.
[Yu Zhao's comment is also quoted in the code.]
Link: https://lkml.kernel.org/r/20210717065911.61497-1-linmiaohe@huawei.com
Link: https://lkml.kernel.org/r/20210717065911.61497-2-linmiaohe@huawei.com
Signed-off-by: Miaohe Lin <linmiaohe@huawei.com>
Reviewed-by: Yu Zhao <yuzhao@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Cc: Alex Shi <alexs@kernel.org>
Cc: Alistair Popple <apopple@nvidia.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Minchan Kim <minchan@kernel.org>
Cc: David Hildenbrand <david@redhat.com>
Cc: Shaohua Li <shli@fb.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hui Su [Thu, 2 Sep 2021 21:59:36 +0000 (14:59 -0700)]
mm/vmpressure: replace vmpressure_to_css() with vmpressure_to_memcg()
We can get memcg directly form vmpr instead of vmpr->memcg->css->memcg, so
add a new func helper vmpressure_to_memcg(). And no code will use
vmpressure_to_css(), so delete it.
Link: https://lkml.kernel.org/r/20210630112146.455103-1-suhui@zeku.com
Signed-off-by: Hui Su <suhui@zeku.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Acked-by: Chris Down <chris@chrisdown.name>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Huang Ying [Thu, 2 Sep 2021 21:59:33 +0000 (14:59 -0700)]
mm/migrate: add sysfs interface to enable reclaim migration
Some method is obviously needed to enable reclaim-based migration.
Just like traditional autonuma, there will be some workloads that will
benefit like workloads with more "static" configurations where hot pages
stay hot and cold pages stay cold. If pages come and go from the hot and
cold sets, the benefits of this approach will be more limited.
The benefits are truly workload-based and *not* hardware-based. We do not
believe that there is a viable threshold where certain hardware
configurations should have this mechanism enabled while others do not.
To be conservative, earlier work defaulted to disable reclaim- based
migration and did not include a mechanism to enable it. This proposes add
a new sysfs file
/sys/kernel/mm/numa/demotion_enabled
as a method to enable it.
We are open to any alternative that allows end users to enable this
mechanism or disable it if workload harm is detected (just like
traditional autonuma).
Once this is enabled page demotion may move data to a NUMA node that does
not fall into the cpuset of the allocating process. This could be
construed to violate the guarantees of cpusets. However, since this is an
opt-in mechanism, the assumption is that anyone enabling it is content to
relax the guarantees.
Link: https://lkml.kernel.org/r/20210721063926.3024591-9-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-10-ying.huang@intel.com
Signed-off-by: Huang Ying <ying.huang@intel.com>
Originally-by: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Zi Yan <ziy@nvidia.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <shy828301@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen [Thu, 2 Sep 2021 21:59:30 +0000 (14:59 -0700)]
mm/vmscan: never demote for memcg reclaim
Global reclaim aims to reduce the amount of memory used on a given node or
set of nodes. Migrating pages to another node serves this purpose.
memcg reclaim is different. Its goal is to reduce the total memory
consumption of the entire memcg, across all nodes. Migration does not
assist memcg reclaim because it just moves page contents between nodes
rather than actually reducing memory consumption.
Link: https://lkml.kernel.org/r/20210715055145.195411-9-ying.huang@intel.com
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Suggested-by: Yang Shi <yang.shi@linux.alibaba.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Keith Busch [Thu, 2 Sep 2021 21:59:26 +0000 (14:59 -0700)]
mm/vmscan: Consider anonymous pages without swap
Reclaim anonymous pages if a migration path is available now that demotion
provides a non-swap recourse for reclaiming anon pages.
Note that this check is subtly different from the can_age_anon_pages()
checks. This mechanism checks whether a specific page in a specific
context can actually be reclaimed, given current swap space and cgroup
limits.
can_age_anon_pages() is a much simpler and more preliminary check which
just says whether there is a possibility of future reclaim.
[kbusch@kernel.org: v11]
Link: https://lkml.kernel.org/r/20210715055145.195411-8-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210721063926.3024591-7-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-8-ying.huang@intel.com
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen [Thu, 2 Sep 2021 21:59:23 +0000 (14:59 -0700)]
mm/vmscan: add helper for querying ability to age anonymous pages
Anonymous pages are kept on their own LRU(s). These lists could
theoretically always be scanned and maintained. But, without swap, there
is currently nothing the kernel can *do* with the results of a scanned,
sorted LRU for anonymous pages.
A check for '!total_swap_pages' currently serves as a valid check as to
whether anonymous LRUs should be maintained. However, another method will
be added shortly: page demotion.
Abstract out the 'total_swap_pages' checks into a helper, give it a
logically significant name, and check for the possibility of page
demotion.
[dave.hansen@linux.intel.com: v11]
Link: https://lkml.kernel.org/r/20210715055145.195411-7-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210721063926.3024591-6-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-7-ying.huang@intel.com
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Greg Thelen <gthelen@google.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yang Shi [Thu, 2 Sep 2021 21:59:19 +0000 (14:59 -0700)]
mm/vmscan: add page demotion counter
Account the number of demoted pages.
Add pgdemote_kswapd and pgdemote_direct VM counters showed in
/proc/vmstat.
[ daveh:
- __count_vm_events() a bit, and made them look at the THP
size directly rather than getting data from migrate_pages()
]
Link: https://lkml.kernel.org/r/20210721063926.3024591-5-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-6-ying.huang@intel.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Wei Xu <weixugc@google.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen [Thu, 2 Sep 2021 21:59:16 +0000 (14:59 -0700)]
mm/migrate: demote pages during reclaim
This is mostly derived from a patch from Yang Shi:
https://lore.kernel.org/linux-mm/
1560468577-101178-10-git-send-email-yang.shi@linux.alibaba.com/
Add code to the reclaim path (shrink_page_list()) to "demote" data to
another NUMA node instead of discarding the data. This always avoids the
cost of I/O needed to read the page back in and sometimes avoids the
writeout cost when the page is dirty.
A second pass through shrink_page_list() will be made if any demotions
fail. This essentially falls back to normal reclaim behavior in the case
that demotions fail. Previous versions of this patch may have simply
failed to reclaim pages which were eligible for demotion but were unable
to be demoted in practice.
For some cases, for example, MADV_PAGEOUT, the pages are always discarded
instead of demoted to follow the kernel API definition. Because
MADV_PAGEOUT is defined as freeing specified pages regardless in which
tier they are.
Note: This just adds the start of infrastructure for migration. It is
actually disabled next to the FIXME in migrate_demote_page_ok().
[dave.hansen@linux.intel.com: v11]
Link: https://lkml.kernel.org/r/20210715055145.195411-5-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210721063926.3024591-4-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-5-ying.huang@intel.com
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Wei Xu <weixugc@google.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Yang Shi [Thu, 2 Sep 2021 21:59:13 +0000 (14:59 -0700)]
mm/migrate: enable returning precise migrate_pages() success count
Under normal circumstances, migrate_pages() returns the number of pages
migrated. In error conditions, it returns an error code. When returning
an error code, there is no way to know how many pages were migrated or not
migrated.
Make migrate_pages() return how many pages are demoted successfully for
all cases, including when encountering errors. Page reclaim behavior will
depend on this in subsequent patches.
Link: https://lkml.kernel.org/r/20210721063926.3024591-3-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-4-ying.huang@intel.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Suggested-by: Oscar Salvador <osalvador@suse.de> [optional parameter]
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen [Thu, 2 Sep 2021 21:59:09 +0000 (14:59 -0700)]
mm/migrate: update node demotion order on hotplug events
Reclaim-based migration is attempting to optimize data placement in memory
based on the system topology. If the system changes, so must the
migration ordering.
The implementation is conceptually simple and entirely unoptimized. On
any memory or CPU hotplug events, assume that a node was added or removed
and recalculate all migration targets. This ensures that the
node_demotion[] array is always ready to be used in case the new reclaim
mode is enabled.
This recalculation is far from optimal, most glaringly that it does not
even attempt to figure out the hotplug event would have some *actual*
effect on the demotion order. But, given the expected paucity of hotplug
events, this should be fine.
Link: https://lkml.kernel.org/r/20210721063926.3024591-2-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-3-ying.huang@intel.com
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Dave Hansen [Thu, 2 Sep 2021 21:59:06 +0000 (14:59 -0700)]
mm/numa: automatically generate node migration order
Patch series "Migrate Pages in lieu of discard", v11.
We're starting to see systems with more and more kinds of memory such as
Intel's implementation of persistent memory.
Let's say you have a system with some DRAM and some persistent memory.
Today, once DRAM fills up, reclaim will start and some of the DRAM
contents will be thrown out. Allocations will, at some point, start
falling over to the slower persistent memory.
That has two nasty properties. First, the newer allocations can end up in
the slower persistent memory. Second, reclaimed data in DRAM are just
discarded even if there are gobs of space in persistent memory that could
be used.
This patchset implements a solution to these problems. At the end of the
reclaim process in shrink_page_list() just before the last page refcount
is dropped, the page is migrated to persistent memory instead of being
dropped.
While I've talked about a DRAM/PMEM pairing, this approach would function
in any environment where memory tiers exist.
This is not perfect. It "strands" pages in slower memory and never brings
them back to fast DRAM. Huang Ying has follow-on work which repurposes
NUMA balancing to promote hot pages back to DRAM.
This is also all based on an upstream mechanism that allows persistent
memory to be onlined and used as if it were volatile:
http://lkml.kernel.org/r/
20190124231441.
37A4A305@viggo.jf.intel.com
With that, the DRAM and PMEM in each socket will be represented as 2
separate NUMA nodes, with the CPUs sit in the DRAM node. So the
general inter-NUMA demotion mechanism introduced in the patchset can
migrate the cold DRAM pages to the PMEM node.
We have tested the patchset with the postgresql and pgbench. On a
2-socket server machine with DRAM and PMEM, the kernel with the patchset
can improve the score of pgbench up to 22.1% compared with that of the
DRAM only + disk case. This comes from the reduced disk read throughput
(which reduces up to 70.8%).
== Open Issues ==
* Memory policies and cpusets that, for instance, restrict allocations
to DRAM can be demoted to PMEM whenever they opt in to this
new mechanism. A cgroup-level API to opt-in or opt-out of
these migrations will likely be required as a follow-on.
* Could be more aggressive about where anon LRU scanning occurs
since it no longer necessarily involves I/O. get_scan_count()
for instance says: "If we have no swap space, do not bother
scanning anon pages"
This patch (of 9):
Prepare for the kernel to auto-migrate pages to other memory nodes with a
node migration table. This allows creating single migration target for
each NUMA node to enable the kernel to do NUMA page migrations instead of
simply discarding colder pages. A node with no target is a "terminal
node", so reclaim acts normally there. The migration target does not
fundamentally _need_ to be a single node, but this implementation starts
there to limit complexity.
When memory fills up on a node, memory contents can be automatically
migrated to another node. The biggest problems are knowing when to
migrate and to where the migration should be targeted.
The most straightforward way to generate the "to where" list would be to
follow the page allocator fallback lists. Those lists already tell us if
memory is full where to look next. It would also be logical to move
memory in that order.
But, the allocator fallback lists have a fatal flaw: most nodes appear in
all the lists. This would potentially lead to migration cycles (A->B,
B->A, A->B, ...).
Instead of using the allocator fallback lists directly, keep a separate
node migration ordering. But, reuse the same data used to generate page
allocator fallback in the first place: find_next_best_node().
This means that the firmware data used to populate node distances
essentially dictates the ordering for now. It should also be
architecture-neutral since all NUMA architectures have a working
find_next_best_node().
RCU is used to allow lock-less read of node_demotion[] and prevent
demotion cycles been observed. If multiple reads of node_demotion[] are
performed, a single rcu_read_lock() must be held over all reads to ensure
no cycles are observed. Details are as follows.
=== What does RCU provide? ===
Imagine a simple loop which walks down the demotion path looking
for the last node:
terminal_node = start_node;
while (node_demotion[terminal_node] != NUMA_NO_NODE) {
terminal_node = node_demotion[terminal_node];
}
The initial values are:
node_demotion[0] = 1;
node_demotion[1] = NUMA_NO_NODE;
and are updated to:
node_demotion[0] = NUMA_NO_NODE;
node_demotion[1] = 0;
What guarantees that the cycle is not observed:
node_demotion[0] = 1;
node_demotion[1] = 0;
and would loop forever?
With RCU, a rcu_read_lock/unlock() can be placed around the loop. Since
the write side does a synchronize_rcu(), the loop that observed the old
contents is known to be complete before the synchronize_rcu() has
completed.
RCU, combined with disable_all_migrate_targets(), ensures that the old
migration state is not visible by the time __set_migration_target_nodes()
is called.
=== What does READ_ONCE() provide? ===
READ_ONCE() forbids the compiler from merging or reordering successive
reads of node_demotion[]. This ensures that any updates are *eventually*
observed.
Consider the above loop again. The compiler could theoretically read the
entirety of node_demotion[] into local storage (registers) and never go
back to memory, and *permanently* observe bad values for node_demotion[].
Note: RCU does not provide any universal compiler-ordering
guarantees:
https://lore.kernel.org/lkml/
20150921204327.GH4029@linux.vnet.ibm.com/
This code is unused for now. It will be called later in the
series.
Link: https://lkml.kernel.org/r/20210721063926.3024591-1-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-1-ying.huang@intel.com
Link: https://lkml.kernel.org/r/20210715055145.195411-2-ying.huang@intel.com
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Reviewed-by: Yang Shi <shy828301@gmail.com>
Reviewed-by: Zi Yan <ziy@nvidia.com>
Reviewed-by: Oscar Salvador <osalvador@suse.de>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Wei Xu <weixugc@google.com>
Cc: David Rientjes <rientjes@google.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: Greg Thelen <gthelen@google.com>
Cc: Keith Busch <kbusch@kernel.org>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav Amit [Thu, 2 Sep 2021 21:59:02 +0000 (14:59 -0700)]
selftests/vm/userfaultfd: wake after copy failure
When userfaultfd copy-ioctl fails since the PTE already exists, an -EEXIST
error is returned and the faulting thread is not woken. The current
userfaultfd test does not wake the faulting thread in such case. The
assumption is presumably that another thread set the PTE through copy/wp
ioctl and would wake the faulting thread or that alternatively the fault
handler would realize there is no need to "must_wait" and continue. This
is not necessarily true.
There is an assumption that the "must_wait" tests in handle_userfault()
are sufficient to provide definitive answer whether the offending PTE is
populated or not. However, userfaultfd_must_wait() test is lockless.
Consequently, concurrent calls to ptep_modify_prot_start(), for instance,
can clear the PTE and can cause userfaultfd_must_wait() to wrongly assume
it is not populated and a wait is needed.
There are therefore 3 options:
(1) Change the tests to wake on copy failure.
(2) Wake faulting thread unconditionally on zero/copy ioctls before
returning -EEXIST.
(3) Change the userfaultfd_must_wait() to hold locks.
This patch took the first approach, but the others are valid solutions
with different tradeoffs.
Link: https://lkml.kernel.org/r/20210808020724.1022515-4-namit@vmware.com
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav Amit [Thu, 2 Sep 2021 21:58:59 +0000 (14:58 -0700)]
userfaultfd: prevent concurrent API initialization
userfaultfd assumes that the enabled features are set once and never
changed after UFFDIO_API ioctl succeeded.
However, currently, UFFDIO_API can be called concurrently from two
different threads, succeed on both threads and leave userfaultfd's
features in non-deterministic state. Theoretically, other uffd operations
(ioctl's and page-faults) can be dispatched while adversely affected by
such changes of features.
Moreover, the writes to ctx->state and ctx->features are not ordered,
which can - theoretically, again - let userfaultfd_ioctl() think that
userfaultfd API completed, while the features are still not initialized.
To avoid races, it is arguably best to get rid of ctx->state. Since there
are only 2 states, record the API initialization in ctx->features as the
uppermost bit and remove ctx->state.
Link: https://lkml.kernel.org/r/20210808020724.1022515-3-namit@vmware.com
Fixes:
9cd75c3cd4c3d ("userfaultfd: non-cooperative: add ability to report non-PF events from uffd descriptor")
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Nadav Amit [Thu, 2 Sep 2021 21:58:56 +0000 (14:58 -0700)]
userfaultfd: change mmap_changing to atomic
Patch series "userfaultfd: minor bug fixes".
Three unrelated bug fixes. The first two addresses possible issues (not
too theoretical ones), but I did not encounter them in practice.
The third patch addresses a test bug that causes the test to fail on my
system. It has been sent before as part of a bigger RFC.
This patch (of 3):
mmap_changing is currently a boolean variable, which is set and cleared
without any lock that protects against concurrent modifications.
mmap_changing is supposed to mark whether userfaultfd page-faults handling
should be retried since mappings are undergoing a change. However,
concurrent calls, for instance to madvise(MADV_DONTNEED), might cause
mmap_changing to be false, although the remove event was still not read
(hence acknowledged) by the user.
Change mmap_changing to atomic_t and increase/decrease appropriately. Add
a debug assertion to see whether mmap_changing is negative.
Link: https://lkml.kernel.org/r/20210808020724.1022515-1-namit@vmware.com
Link: https://lkml.kernel.org/r/20210808020724.1022515-2-namit@vmware.com
Fixes:
df2cc96e77011 ("userfaultfd: prevent non-cooperative events vs mcopy_atomic races")
Signed-off-by: Nadav Amit <namit@vmware.com>
Cc: Mike Rapoport <rppt@linux.vnet.ibm.com>
Cc: Peter Xu <peterx@redhat.com>
Cc: Axel Rasmussen <axelrasmussen@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike Kravetz [Thu, 2 Sep 2021 21:58:53 +0000 (14:58 -0700)]
hugetlb: fix hugetlb cgroup refcounting during vma split
Guillaume Morin reported hitting the following WARNING followed by GPF or
NULL pointer deference either in cgroups_destroy or in the kill_css path.:
percpu ref (css_release) <= 0 (-1) after switching to atomic
WARNING: CPU: 23 PID: 130 at lib/percpu-refcount.c:196 percpu_ref_switch_to_atomic_rcu+0x127/0x130
CPU: 23 PID: 130 Comm: ksoftirqd/23 Kdump: loaded Tainted: G O 5.10.60 #1
RIP: 0010:percpu_ref_switch_to_atomic_rcu+0x127/0x130
Call Trace:
rcu_core+0x30f/0x530
rcu_core_si+0xe/0x10
__do_softirq+0x103/0x2a2
run_ksoftirqd+0x2b/0x40
smpboot_thread_fn+0x11a/0x170
kthread+0x10a/0x140
ret_from_fork+0x22/0x30
Upon further examination, it was discovered that the css structure was
associated with hugetlb reservations.
For private hugetlb mappings the vma points to a reserve map that
contains a pointer to the css. At mmap time, reservations are set up
and a reference to the css is taken. This reference is dropped in the
vma close operation; hugetlb_vm_op_close. However, if a vma is split no
additional reference to the css is taken yet hugetlb_vm_op_close will be
called twice for the split vma resulting in an underflow.
Fix by taking another reference in hugetlb_vm_op_open. Note that the
reference is only taken for the owner of the reserve map. In the more
common fork case, the pointer to the reserve map is cleared for
non-owning vmas.
Link: https://lkml.kernel.org/r/20210830215015.155224-1-mike.kravetz@oracle.com
Fixes:
e9fe92ae0cd2 ("hugetlb_cgroup: add reservation accounting for private mappings")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Guillaume Morin <guillaume@morinfr.org>
Suggested-by: Guillaume Morin <guillaume@morinfr.org>
Tested-by: Guillaume Morin <guillaume@morinfr.org>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Mike Kravetz [Thu, 2 Sep 2021 21:58:50 +0000 (14:58 -0700)]
hugetlb: before freeing hugetlb page set dtor to appropriate value
When removing a hugetlb page from the pool the ref count is set to one (as
the free page has no ref count) and compound page destructor is set to
NULL_COMPOUND_DTOR. Since a subsequent call to free the hugetlb page will
call __free_pages for non-gigantic pages and free_gigantic_page for
gigantic pages the destructor is not used.
However, consider the following race with code taking a speculative
reference on the page:
Thread 0 Thread 1
-------- --------
remove_hugetlb_page
set_page_refcounted(page);
set_compound_page_dtor(page,
NULL_COMPOUND_DTOR);
get_page_unless_zero(page)
__update_and_free_page
__free_pages(page,
huge_page_order(h));
/* Note that __free_pages() will simply drop
the reference to the page. */
put_page(page)
__put_compound_page()
destroy_compound_page
NULL_COMPOUND_DTOR
BUG: kernel NULL pointer
dereference, address:
0000000000000000
To address this race, set the dtor to the normal compound page dtor for
non-gigantic pages. The dtor for gigantic pages does not matter as
gigantic pages are changed from a compound page to 'just a group of pages'
before freeing. Hence, the destructor is not used.
Link: https://lkml.kernel.org/r/20210809184832.18342-4-mike.kravetz@oracle.com
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Muchun Song <songmuchun@bytedance.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Oscar Salvador <osalvador@suse.de>
Cc: David Hildenbrand <david@redhat.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Naoya Horiguchi <naoya.horiguchi@linux.dev>
Cc: Mina Almasry <almasrymina@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>