platform/kernel/linux-starfive.git
4 years agoperf evsel: Rename perf_evsel__is_aux_event() to evsel__is_aux_event()
Arnaldo Carvalho de Melo [Wed, 29 Apr 2020 18:51:38 +0000 (15:51 -0300)]
perf evsel: Rename perf_evsel__is_aux_event() to evsel__is_aux_event()

As it is a 'struct evsel' method, not part of tools/lib/perf/, aka
libperf, to whom the perf_ prefix belongs.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evsel: Rename perf_evsel__find_pmu() to evsel__find_pmu()
Arnaldo Carvalho de Melo [Wed, 29 Apr 2020 18:50:10 +0000 (15:50 -0300)]
perf evsel: Rename perf_evsel__find_pmu() to evsel__find_pmu()

As it is a 'struct evsel' method, not part of tools/lib/perf/, aka
libperf, to whom the perf_ prefix belongs.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evsel: Rename perf_evsel__compute_deltas() to evsel__compute_deltas()
Arnaldo Carvalho de Melo [Wed, 29 Apr 2020 18:47:38 +0000 (15:47 -0300)]
perf evsel: Rename perf_evsel__compute_deltas() to evsel__compute_deltas()

As it is a 'struct evsel' method, not part of tools/lib/perf/, aka
libperf, to whom the perf_ prefix belongs.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evsel: Rename perf_evsel__nr_cpus() to evsel__nr_cpus()
Arnaldo Carvalho de Melo [Wed, 29 Apr 2020 18:45:09 +0000 (15:45 -0300)]
perf evsel: Rename perf_evsel__nr_cpus() to evsel__nr_cpus()

As it is a 'struct evsel' method, not part of tools/lib/perf/, aka
libperf, to whom the perf_ prefix belongs.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evsel: Rename 'struct perf_evsel__sb_cb_t' to 'struct evsel__sb_cb_t'
Arnaldo Carvalho de Melo [Wed, 29 Apr 2020 18:42:16 +0000 (15:42 -0300)]
perf evsel: Rename 'struct perf_evsel__sb_cb_t' to 'struct evsel__sb_cb_t'

As the "perf_" prefix should be restricted to functions and types in
tools/lib/perf/, aka libperf, this way we reduce a bit the confusion for
types only in libperf or the ones in the more contained tools/perf/
project.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf intel-pt: Update documentation about using /proc/kcore
Adrian Hunter [Wed, 29 Apr 2020 15:07:51 +0000 (18:07 +0300)]
perf intel-pt: Update documentation about using /proc/kcore

Update documentation to reflect the advent of the --kcore option for
'perf record'.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-10-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf intel-pt: Update documentation about itrace G and L options
Adrian Hunter [Wed, 29 Apr 2020 15:07:50 +0000 (18:07 +0300)]
perf intel-pt: Update documentation about itrace G and L options

Provide a little more information about the new G and L options,
particularly the issue with large PEBs.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-9-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf intel-pt: Add support for synthesizing branch stacks for regular events
Adrian Hunter [Wed, 29 Apr 2020 15:07:49 +0000 (18:07 +0300)]
perf intel-pt: Add support for synthesizing branch stacks for regular events

Use the new thread_stack__br_sample_late() function to create a thread
stack for regular events.

Example:

 # perf record --kcore --aux-sample -e '{intel_pt//,cycles:ppp}' -c 10000 uname
 Linux
 [ perf record: Woken up 2 times to write data ]
 [ perf record: Captured and wrote 0.743 MB perf.data ]
 # perf report --itrace=Le --stdio | head -30 | tail -18

 # Samples: 11K of event 'cycles:ppp'
 # Event count (approx.): 11648
 #
 # Overhead  Command  Source Shared Object  Source Symbol                 Target Symbol                 Basic Block Cycles
 # ........  .......  ....................  ............................  ............................  ..................
 #
      5.49%  uname    libc-2.30.so          [.] _dl_addr                  [.] _dl_addr                  -
      2.41%  uname    ld-2.30.so            [.] _dl_relocate_object       [.] _dl_relocate_object       -
      2.31%  uname    ld-2.30.so            [.] do_lookup_x               [.] do_lookup_x               -
      2.17%  uname    [kernel.kallsyms]     [k] unmap_page_range          [k] unmap_page_range          -
      2.05%  uname    ld-2.30.so            [k] _dl_start                 [k] _dl_start                 -
      1.97%  uname    ld-2.30.so            [.] _dl_lookup_symbol_x       [.] _dl_lookup_symbol_x       -
      1.94%  uname    [kernel.kallsyms]     [k] filemap_map_pages         [k] filemap_map_pages         -
      1.60%  uname    [kernel.kallsyms]     [k] __handle_mm_fault         [k] __handle_mm_fault         -
      1.44%  uname    [kernel.kallsyms]     [k] page_add_file_rmap        [k] page_add_file_rmap        -
      1.12%  uname    [kernel.kallsyms]     [k] vma_interval_tree_insert  [k] vma_interval_tree_insert  -
      0.94%  uname    [kernel.kallsyms]     [k] perf_iterate_ctx          [k] perf_iterate_ctx          -

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-8-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf thread-stack: Add thread_stack__br_sample_late()
Adrian Hunter [Wed, 29 Apr 2020 15:07:48 +0000 (18:07 +0300)]
perf thread-stack: Add thread_stack__br_sample_late()

Add a thread stack function to create a branch stack for hardware events
where the sample records get created some time after the event occurred.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-7-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evsel: Add support for synthesized branch stack sample type
Adrian Hunter [Wed, 29 Apr 2020 15:07:47 +0000 (18:07 +0300)]
perf evsel: Add support for synthesized branch stack sample type

Allow for a synthesized branch stack to be added to samples. As with
synthesized call chains, the sample type cannot be changed because it is
needed to continue to parse events. So add and use helper function
evsel__has_br_stack() to indicate a branch stack, whether original or
synthesized.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-6-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf auxtrace: Add option to synthesize branch stack for regular events
Adrian Hunter [Wed, 29 Apr 2020 15:07:46 +0000 (18:07 +0300)]
perf auxtrace: Add option to synthesize branch stack for regular events

There is an existing option to synthesize branch stacks for synthesized
events. Add a new option to synthesize branch stacks for regular events.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-5-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf intel-pt: Change branch stack support to use thread-stacks
Adrian Hunter [Wed, 29 Apr 2020 15:07:45 +0000 (18:07 +0300)]
perf intel-pt: Change branch stack support to use thread-stacks

Change Intel PT's branch stack support to use thread stacks. The
advantages of using branch stack support from the thread-stack are:

1. the branches are accumulated separately for each thread
2. the branch stack is cleared only in between continuous traces

This helps pave the way for adding branch stacks to regular events, not
just synthesized events as at present.

While the 2 approaches are not identical, in simple cases the results
can be identical e.g.

  Before:

    # perf record --kcore -e intel_pt// uname
    # perf script --itrace=i10usl -F+brstacksym,+addr,+flags > cmp1.txt

  After:

    # perf script --itrace=i10usl -F+brstacksym,+addr,+flags > cmp2.txt
    # diff -s cmp1.txt cmp2.txt
    Files cmp1.txt and cmp2.txt are identical

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-4-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf intel-pt: Consolidate thread-stack use condition
Adrian Hunter [Wed, 29 Apr 2020 15:07:44 +0000 (18:07 +0300)]
perf intel-pt: Consolidate thread-stack use condition

The components of the condition do not change, so consolidate them in
one variable.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-3-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf thread-stack: Add branch stack support
Adrian Hunter [Wed, 29 Apr 2020 15:07:43 +0000 (18:07 +0300)]
perf thread-stack: Add branch stack support

Intel PT already has support for creating branch stacks for each context
(per-cpu or per-thread). In the more common per-cpu case, the branch stack
is not separated for different threads, instead being cleared in between
each sample.

That approach will not work very well for adding branch stacks to
regular events. The branch stacks really need to be accumulated
separately for each thread.

As a start to accomplishing that, this patch adds support for putting
branch stack support into the thread-stack. The advantages are:

1. the branches are accumulated separately for each thread
2. the branch stack is cleared only in between continuous traces

This helps pave the way for adding branch stacks to regular events, not
just synthesized events as at present.

Signed-off-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Link: http://lore.kernel.org/lkml/20200429150751.12570-2-adrian.hunter@intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf tools: Simplify checking if SMT is active.
Konstantin Khlebnikov [Wed, 29 Apr 2020 16:23:41 +0000 (19:23 +0300)]
perf tools: Simplify checking if SMT is active.

SMT now could be disabled via "/sys/devices/system/cpu/smt/control".

Status is shown in "/sys/devices/system/cpu/smt/active" simply as "0" / "1".

If this knob isn't here then fallback to checking topology as before.

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/158817741394.748034.9273604089138009552.stgit@buzz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf tools: Fix reading new topology attribute "core_cpus"
Konstantin Khlebnikov [Wed, 29 Apr 2020 16:19:47 +0000 (19:19 +0300)]
perf tools: Fix reading new topology attribute "core_cpus"

Check if access("devices/system/cpu/cpu%d/topology/core_cpus", F_OK)
fails, which will happen unless the current directory is "/sys".

Simply try to read this file first.

Fixes: 0ccdb8407a46 ("perf tools: Apply new CPU topology sysfs attributes")
Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/158817718710.747528.11009278875028211991.stgit@buzz
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agolibperf evlist: Fix a refcount leak
Ian Rogers [Thu, 19 Mar 2020 02:31:01 +0000 (19:31 -0700)]
libperf evlist: Fix a refcount leak

Memory leaks found by applying LLVM's libfuzzer on the tools/perf
parse_events function.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200319023101.82458-2-irogers@google.com
[ Did a minor adjustment due to some other previous patch having already set evlist->all_cpus to NULL at perf_evlist__exit() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf parse-events: Fix another memory leaks found on parse_events()
Ian Rogers [Thu, 19 Mar 2020 02:31:00 +0000 (19:31 -0700)]
perf parse-events: Fix another memory leaks found on parse_events()

Fix another memory leak found by applying LLVM's libfuzzer on parse_events().

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200319023101.82458-1-irogers@google.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf parse-events: Fix memory leaks found on parse_events
Ian Rogers [Thu, 19 Mar 2020 02:31:00 +0000 (19:31 -0700)]
perf parse-events: Fix memory leaks found on parse_events

free_list_evsel() deals with tools/perf/ evsels, not with libperf
perf_evsels, use the right destructor and avoid a leak, as
evsel__delete() will delete something perf_evsel__delete() doesn't.

Signed-off-by: Ian Rogers <irogers@google.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200319023101.82458-1-irogers@google.com
[ split from a larger patch ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf parse-events: Fix memory leaks found on parse_events
Ian Rogers [Thu, 19 Mar 2020 02:31:00 +0000 (19:31 -0700)]
perf parse-events: Fix memory leaks found on parse_events

Fix a memory leak found by applying LLVM's libfuzzer on parse_events().

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: clang-built-linux@googlegroups.com
Link: http://lore.kernel.org/lkml/20200319023101.82458-1-irogers@google.com
[ split from a larger patch, use zfree() ]
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agolibperf: Add NULL pointer check for cpu_map iteration and NULL assignment for all_cpus.
He Zhe [Sun, 8 Mar 2020 10:59:17 +0000 (18:59 +0800)]
libperf: Add NULL pointer check for cpu_map iteration and NULL assignment for all_cpus.

A NULL pointer may be passed to perf_cpu_map__cpu and then cause a
crash, such as the one commit cb71f7d43ece ("libperf: Setup initial
evlist::all_cpus value") fix.

Signed-off-by: He Zhe <zhe.he@windriver.com>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Kyle Meyer <meyerk@hpe.com>
Link: http://lore.kernel.org/lkml/1583665157-349023-1-git-send-email-zhe.he@windriver.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf record: Move side band evlist setup to separate routine
Arnaldo Carvalho de Melo [Tue, 28 Apr 2020 17:58:29 +0000 (14:58 -0300)]
perf record: Move side band evlist setup to separate routine

It is quite big by now, move that code to a separate
record__setup_sb_evlist() routine.

Suggested-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-9-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf record: Introduce --switch-output-event
Arnaldo Carvalho de Melo [Mon, 27 Apr 2020 20:56:37 +0000 (17:56 -0300)]
perf record: Introduce --switch-output-event

Now we can use it with --overwrite to have a flight recorder mode that
gets snapshot requests from arbitrary events that are processed in the
side band thread together with the PERF_RECORD_BPF_EVENT processing.

Example:

To collect scheduler events until a recvmmsg syscall happens, system
wide:

  [root@five a]# rm -f perf.data.2020042717*
  [root@five a]# perf record --overwrite -e sched:*switch,syscalls:*recvmmsg --switch-output-event syscalls:sys_enter_recvmmsg
  [ perf record: dump data: Woken up 1 times ]
  [ perf record: Dump perf.data.2020042717585458 ]
  [ perf record: dump data: Woken up 1 times ]
  [ perf record: Dump perf.data.2020042717590235 ]
  [ perf record: dump data: Woken up 1 times ]
  [ perf record: Dump perf.data.2020042717590398 ]
  ^C[ perf record: Woken up 1 times to write data ]
  [ perf record: Dump perf.data.2020042717590511 ]
  [ perf record: Captured and wrote 7.244 MB perf.data.<timestamp> ]

So in the above case we had 3 snapshots, the fourth was forced by
control+C:

  [root@five a]# ls -la
  total 20440
  drwxr-xr-x.  2 root root    4096 Apr 27 17:59 .
  dr-xr-x---. 12 root root    4096 Apr 27 17:46 ..
  -rw-------.  1 root root 3936125 Apr 27 17:58 perf.data.2020042717585458
  -rw-------.  1 root root 5074869 Apr 27 17:59 perf.data.2020042717590235
  -rw-------.  1 root root 4291037 Apr 27 17:59 perf.data.2020042717590398
  -rw-------.  1 root root 7617037 Apr 27 17:59 perf.data.2020042717590511
  [root@five a]#

One can make this more precise by adding the switch output event to the
main -e events list, as since this is done asynchronously, a few events
after the signal event will appear in the snapshots, as can be seen
with:

  [root@five a]# rm -f perf.data.20200427175*
  [root@five a]# perf record --overwrite -e sched:*switch,syscalls:*recvmmsg --switch-output-event syscalls:sys_enter_recvmmsg
  [ perf record: dump data: Woken up 1 times ]
  [ perf record: Dump perf.data.2020042718024203 ]
  [ perf record: dump data: Woken up 1 times ]
  [ perf record: Dump perf.data.2020042718024301 ]
  [ perf record: dump data: Woken up 1 times ]
  [ perf record: Dump perf.data.2020042718024484 ]
  ^C[ perf record: Woken up 1 times to write data ]
  [ perf record: Dump perf.data.2020042718024562 ]
  [ perf record: Captured and wrote 7.337 MB perf.data.<timestamp> ]
  [root@five a]# perf script -i perf.data.2020042718024203 | tail -15
       PacerThread 148586 [005] 122.830729: sched:sched_switch: prev_comm=PacerThread prev_pid=148586...
           swapper      0 [000] 122.833588: sched:sched_switch: prev_comm=swapper/0 prev_pid=...
    NetworkManager   1251 [000] 122.833619: syscalls:sys_enter_recvmmsg: fd: 0x0000001c, mmsg: 0x7ffe83054a1...
           swapper      0 [002] 122.833624: sched:sched_switch: prev_comm=swapper/2 prev_pid=...
           swapper      0 [003] 122.833624: sched:sched_switch: prev_comm=swapper/3 prev_pid=...
    NetworkManager   1251 [000] 122.833626: syscalls:sys_exit_recvmmsg: 0x1
   kworker/3:3-eve 158946 [003] 122.833628: sched:sched_switch: prev_comm=kworker/3:3 prev_pid=15894...
           swapper      0 [004] 122.833641: sched:sched_switch: prev_comm=swapper/4 prev_pid=...
    NetworkManager   1251 [000] 122.833642: sched:sched_switch: prev_comm=NetworkManage...
              perf 228273 [002] 122.833645: sched:sched_switch: prev_comm=perf prev_pid=22827...
           swapper      0 [011] 122.833646: sched:sched_switch: prev_comm=swapper/1...
           swapper      0 [002] 122.833648: sched:sched_switch: prev_comm=swapper/...
   kworker/0:2-eve 207387 [000] 122.833648: sched:sched_switch: prev_comm=kworker/0:2 prev_pid=20738...
   kworker/2:3-eve 232038 [002] 122.833652: sched:sched_switch: prev_comm=kworker/2:3 prev_pid=23203...
              perf 235825 [003] 122.833653: sched:sched_switch: prev_comm=perf prev_pid=23582...
  [root@five a]#

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-8-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agolibsubcmd: Introduce OPT_CALLBACK_SET()
Arnaldo Carvalho de Melo [Tue, 28 Apr 2020 12:16:25 +0000 (09:16 -0300)]
libsubcmd: Introduce OPT_CALLBACK_SET()

To register that an option was set, like with the upcoming 'perf record
--switch-output-option' one.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-7-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evlist: Allow reusing the side band thread for more purposes
Arnaldo Carvalho de Melo [Mon, 27 Apr 2020 20:54:27 +0000 (17:54 -0300)]
perf evlist: Allow reusing the side band thread for more purposes

I.e. so far we had just one event in that side band thread, a dummy one
with attr.bpf_event set, so that 'perf record' can go ahead and ask the
kernel for further information about BPF programs being loaded.

Allow for more than one event to be there, so that we can use it as
well for the upcoming --switch-output-event feature.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-6-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evlist: Move the sideband thread routines to separate object
Arnaldo Carvalho de Melo [Tue, 5 May 2020 15:18:21 +0000 (12:18 -0300)]
perf evlist: Move the sideband thread routines to separate object

To avoid dragging more stuff into the perf python binding in the
following csets.

Reported-by: Jiri Olsa <jolsa@kernel.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf parse-events: Add parse_events_option() variant that creates evlist
Arnaldo Carvalho de Melo [Mon, 27 Apr 2020 16:58:11 +0000 (13:58 -0300)]
perf parse-events: Add parse_events_option() variant that creates evlist

For the upcoming --switch-output-event option we want to create the side
band event, populate it with the specified events and then, if it is
present multiple times, go on adding to it, then, if the BPF tracking is
required, use the first event to set its attr.bpf_event to get those
PERF_RECORD_BPF_EVENT metadata events too.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-5-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf bpf: Decouple creating the evlist from adding the SB event
Arnaldo Carvalho de Melo [Fri, 24 Apr 2020 15:24:51 +0000 (12:24 -0300)]
perf bpf: Decouple creating the evlist from adding the SB event

Renaming bpf_event__add_sb_event() to evlist__add_sb_event() and
requiring that the evlist be allocated beforehand.

This will allow using the same side band thread and evlist to be used
for multiple purposes in addition to react to PERF_RECORD_BPF_EVENT soon
after they are generated.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-4-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf top: Move sb_evlist to 'struct perf_top'
Arnaldo Carvalho de Melo [Fri, 24 Apr 2020 13:40:54 +0000 (10:40 -0300)]
perf top: Move sb_evlist to 'struct perf_top'

Where state related to a 'perf top' session is grouped.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-3-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf record: Move sb_evlist to 'struct record'
Arnaldo Carvalho de Melo [Fri, 24 Apr 2020 13:24:04 +0000 (10:24 -0300)]
perf record: Move sb_evlist to 'struct record'

Where state related to a 'perf record' session is grouped.

Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Song Liu <songliubraving@fb.com>
Link: http://lore.kernel.org/lkml/20200429131106.27974-2-acme@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf tools: Move routines that probe for perf API features to separate file
Arnaldo Carvalho de Melo [Tue, 5 May 2020 14:49:08 +0000 (11:49 -0300)]
perf tools: Move routines that probe for perf API features to separate file

Trying to disentangle this a bit further, unfortunately it uses
parse_events(), its interesting to have it separated anyway, so do it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf vendor events power9: Add hv_24x7 socket/chip level metric events
Kajol Jain [Wed, 1 Apr 2020 20:33:40 +0000 (02:03 +0530)]
perf vendor events power9: Add hv_24x7 socket/chip level metric events

The hv_24×7 feature in IBM® POWER9â„¢ processor-based servers provide the
facility to continuously collect large numbers of hardware performance
metrics efficiently and accurately.

This patch adds hv_24x7  metric file for different Socket/chip
resources.

Result:

power9 platform:

  command:# ./perf stat --metric-only -M Memory_RD_BW_Chip -C 0 -I 1000

     1.000096188          0.9           0.3
     2.000285720          0.5           0.1
     3.000424990          0.4           0.1

  command:# ./perf stat --metric-only -M PowerBUS_Frequency -C 0 -I 1000

     1.000097981          2.3           2.3
     2.000291713          2.3           2.3
     3.000421719          2.3           2.3
     4.000550912          2.3           2.3

Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-8-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf tools: Enable Hz/hz prinitg for --metric-only option
Kajol Jain [Wed, 1 Apr 2020 20:33:39 +0000 (02:03 +0530)]
perf tools: Enable Hz/hz prinitg for --metric-only option

Commit 54b5091606c18 ("perf stat: Implement --metric-only mode") added
function 'valid_only_metric()' which drops "Hz" or "hz", if it is part
of "ScaleUnit". This patch enable it since hv_24x7 supports couple of
frequency events.

Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-7-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf tests expr: Added test for runtime param in metric expression
Kajol Jain [Wed, 1 Apr 2020 20:33:38 +0000 (02:03 +0530)]
perf tests expr: Added test for runtime param in metric expression

Added test case for parsing  "?" in metric expression.

Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-6-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf metricgroups: Enhance JSON/metric infrastructure to handle "?"
Kajol Jain [Wed, 1 Apr 2020 20:33:37 +0000 (02:03 +0530)]
perf metricgroups: Enhance JSON/metric infrastructure to handle "?"

Patch enhances current metric infrastructure to handle "?" in the metric
expression. The "?" can be use for parameters whose value not known
while creating metric events and which can be replace later at runtime
to the proper value. It also add flexibility to create multiple events
out of single metric event added in JSON file.

Patch adds function 'arch_get_runtimeparam' which is a arch specific
function, returns the count of metric events need to be created.  By
default it return 1.

This infrastructure needed for hv_24x7 socket/chip level events.
"hv_24x7" chip level events needs specific chip-id to which the data is
requested. Function 'arch_get_runtimeparam' implemented in header.c
which extract number of sockets from sysfs file "sockets" under
"/sys/devices/hv_24x7/interface/".

With this patch basically we are trying to create as many metric events
as define by runtime_param.

For that one loop is added in function 'metricgroup__add_metric', which
create multiple events at run time depend on return value of
'arch_get_runtimeparam' and merge that event in 'group_list'.

To achieve that we are actually passing this parameter value as part of
`expr__find_other` function and changing "?" present in metric
expression with this value.

As in our JSON file, there gonna be single metric event, and out of
which we are creating multiple events.

To understand which data count belongs to which parameter value,
we also printing param value in generic_metric function.

For example,

  command:# ./perf stat  -M PowerBUS_Frequency -C 0 -I 1000
    1.000101867  9,356,933  hv_24x7/pm_pb_cyc,chip=0/ #  2.3 GHz  PowerBUS_Frequency_0
    1.000101867  9,366,134  hv_24x7/pm_pb_cyc,chip=1/ #  2.3 GHz  PowerBUS_Frequency_1
    2.000314878  9,365,868  hv_24x7/pm_pb_cyc,chip=0/ #  2.3 GHz  PowerBUS_Frequency_0
    2.000314878  9,366,092  hv_24x7/pm_pb_cyc,chip=1/ #  2.3 GHz  PowerBUS_Frequency_1

So, here _0 and _1 after PowerBUS_Frequency specify parameter value.

Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Anju T Sudhakar <anju@linux.vnet.ibm.com>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Jin Yao <yao.jin@linux.intel.com>
Cc: Joe Mario <jmario@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Michael Petlan <mpetlan@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Paul Mackerras <paulus@ozlabs.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Cc: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: linuxppc-dev@lists.ozlabs.org
Link: http://lore.kernel.org/lkml/20200401203340.31402-5-kjain@linux.ibm.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf pmu: Fix function name in comment, its get_cpuid_str(), not get_cpustr()
Shaokun Zhang [Wed, 29 Apr 2020 06:33:12 +0000 (14:33 +0800)]
perf pmu: Fix function name in comment, its get_cpuid_str(), not get_cpustr()

get_cpuid_str() is used in tools/perf/arch/xxx/util/header.c,
fix the name in comment.

Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Cc: Andi Kleen <ak@linux.intel.com>
Link: http://lore.kernel.org/lkml/1588141992-48382-1-git-send-email-zhangshaokun@hisilicon.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf report: Fix warning assignment of 0/1 to bool variable
Zou Wei [Sun, 26 Apr 2020 12:38:03 +0000 (20:38 +0800)]
perf report: Fix warning assignment of 0/1 to bool variable

Fixes coccicheck warning:

  tools/perf/builtin-report.c:1403:2-34: WARNING: Assignment of 0/1 to bool variable

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/1587904683-3510-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf tools: Remove unneeded semicolons
Zou Wei [Tue, 28 Apr 2020 09:18:43 +0000 (17:18 +0800)]
perf tools: Remove unneeded semicolons

Fixes coccicheck warnings:

  tools/perf/builtin-diff.c:1565:2-3: Unneeded semicolon
  tools/perf/builtin-lock.c:778:2-3: Unneeded semicolon
  tools/perf/builtin-mem.c:126:2-3: Unneeded semicolon
  tools/perf/util/intel-pt-decoder/intel-pt-pkt-decoder.c:555:2-3: Unneeded semicolon
  tools/perf/util/ordered-events.c:317:2-3: Unneeded semicolon
  tools/perf/util/synthetic-events.c:1131:2-3: Unneeded semicolon
  tools/perf/util/trace-event-read.c:78:2-3: Unneeded semicolon

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/1588065523-71423-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf c2c: Remove unneeded semicolon
Zou Wei [Tue, 28 Apr 2020 08:58:56 +0000 (16:58 +0800)]
perf c2c: Remove unneeded semicolon

Fixes coccicheck warnings:

 tools/perf/builtin-c2c.c:1712:2-3: Unneeded semicolon
 tools/perf/builtin-c2c.c:1928:2-3: Unneeded semicolon
 tools/perf/builtin-c2c.c:2962:2-3: Unneeded semicolon

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/1588064336-70456-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agolibtraceevent: Remove unneeded semicolon
Zou Wei [Tue, 28 Apr 2020 09:12:01 +0000 (17:12 +0800)]
libtraceevent: Remove unneeded semicolon

Fixes coccicheck warning:

 tools/lib/traceevent/kbuffer-parse.c:441:2-3: Unneeded semicolon

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Zou Wei <zou_wei@huawei.com>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Link: http://lore.kernel.org/lkml/1588065121-71236-1-git-send-email-zou_wei@huawei.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf script: Remove extraneous newline in perf_sample__fprintf_regs()
Stephane Eranian [Sat, 18 Apr 2020 23:19:08 +0000 (16:19 -0700)]
perf script: Remove extraneous newline in perf_sample__fprintf_regs()

When printing iregs, there was a double newline printed because
perf_sample__fprintf_regs() was printing its own and then at the end of
all fields, perf script was adding one.  This was causing blank line in
the output:

Before:

  $ perf script -Fip,iregs
             401b8d ABI:2    DX:0x100    SI:0x4a8340    DI:0x4a9340

             401b8d ABI:2    DX:0x100    SI:0x4a9340    DI:0x4a8340

             401b8d ABI:2    DX:0x100    SI:0x4a8340    DI:0x4a9340

             401b8d ABI:2    DX:0x100    SI:0x4a9340    DI:0x4a8340

After:

  $ perf script -Fip,iregs
             401b8d ABI:2    DX:0x100    SI:0x4a8340    DI:0x4a9340
             401b8d ABI:2    DX:0x100    SI:0x4a9340    DI:0x4a8340
             401b8d ABI:2    DX:0x100    SI:0x4a8340    DI:0x4a9340

Committer testing:

First we need to figure out how to request that registers be recorded,
so we use:

  # perf record -h reg

   Usage: perf record [<options>] [<command>]
      or: perf record [<options>] -- <command> [<options>]

      -I, --intr-regs[=<any register>]
                            sample selected machine registers on interrupt, use '-I?' to list register names
          --buildid-all     Record build-id of all DSOs regardless of hits
          --user-regs[=<any register>]
                            sample selected machine registers on interrupt, use '--user-regs=?' to list register names

  #

Ok, now lets ask for them all:

  # perf record -a --intr-regs --user-regs sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 4.105 MB perf.data (2760 samples) ]
  #

Lets look at the first 6 output lines:

  # perf script -Fip,iregs | head -6
   ffffffff8a06f2f4 ABI:2    AX:0xffffd168fee0a980    BX:0xffff8a23b087f000    CX:0xfffeb69aaeb25d73    DX:0xffff8a253e8310f0    SI:0xfffffff9bafe7359    DI:0xffffb1690204fb10    BP:0xffffd168fee0a950    SP:0xffffb1690204fb88    IP:0xffffffff8a06f2f4 FLAGS:0x4e    CS:0x10    SS:0x18    R8:0x1495f0a91129a    R9:0xffff8a23b087f000   R10:0x1   R11:0xffffffff   R12:0x0   R13:0xffff8a253e827e00   R14:0xffffd168fee0aa5c   R15:0xffffd168fee0a980

   ffffffff8a06f2f4 ABI:2    AX:0x0    BX:0xffffd168fee0a950    CX:0x5684cc1118491900    DX:0x0    SI:0xffffd168fee0a9d0    DI:0x202    BP:0xffffb1690204fd70    SP:0xffffb1690204fd20    IP:0xffffffff8a06f2f4 FLAGS:0x24e    CS:0x10    SS:0x18    R8:0x0    R9:0xffffd168fee0a9d0   R10:0x1   R11:0xffffffff   R12:0xffffffff8a23e480   R13:0xffff8a23b087f240   R14:0xffff8a23b087f000   R15:0xffffd168fee0a950

   ffffffff8a06f2f4 ABI:2    AX:0x0    BX:0x0    CX:0x7f25f334335b    DX:0x0    SI:0x2400    DI:0x4    BP:0x7fff5f264570    SP:0x7fff5f264538    IP:0xffffffff8a06f2f4 FLAGS:0x24e    CS:0x10    SS:0x2b    R8:0x0    R9:0x2312d20   R10:0x0   R11:0x246   R12:0x22cc0e0   R13:0x0   R14:0x0   R15:0x22d0780

  #

Reproduced, apply the patch and:

[root@five ~]# perf script -Fip,iregs | head -6
 ffffffff8a06f2f4 ABI:2    AX:0xffffd168fee0a980    BX:0xffff8a23b087f000    CX:0xfffeb69aaeb25d73    DX:0xffff8a253e8310f0    SI:0xfffffff9bafe7359    DI:0xffffb1690204fb10    BP:0xffffd168fee0a950    SP:0xffffb1690204fb88    IP:0xffffffff8a06f2f4 FLAGS:0x4e    CS:0x10    SS:0x18    R8:0x1495f0a91129a    R9:0xffff8a23b087f000   R10:0x1   R11:0xffffffff   R12:0x0   R13:0xffff8a253e827e00   R14:0xffffd168fee0aa5c   R15:0xffffd168fee0a980
 ffffffff8a06f2f4 ABI:2    AX:0x0    BX:0xffffd168fee0a950    CX:0x5684cc1118491900    DX:0x0    SI:0xffffd168fee0a9d0    DI:0x202    BP:0xffffb1690204fd70    SP:0xffffb1690204fd20    IP:0xffffffff8a06f2f4 FLAGS:0x24e    CS:0x10    SS:0x18    R8:0x0    R9:0xffffd168fee0a9d0   R10:0x1   R11:0xffffffff   R12:0xffffffff8a23e480   R13:0xffff8a23b087f240   R14:0xffff8a23b087f000   R15:0xffffd168fee0a950
 ffffffff8a06f2f4 ABI:2    AX:0x0    BX:0x0    CX:0x7f25f334335b    DX:0x0    SI:0x2400    DI:0x4    BP:0x7fff5f264570    SP:0x7fff5f264538    IP:0xffffffff8a06f2f4 FLAGS:0x24e    CS:0x10    SS:0x2b    R8:0x0    R9:0x2312d20   R10:0x0   R11:0x246   R12:0x22cc0e0   R13:0x0   R14:0x0   R15:0x22d0780
 ffffffff8a24074b ABI:2    AX:0xcb    BX:0xcb    CX:0x0    DX:0x0    SI:0xffffb1690204ff58    DI:0xcb    BP:0xffffb1690204ff58    SP:0xffffb1690204ff40    IP:0xffffffff8a24074b FLAGS:0x24e    CS:0x10    SS:0x18    R8:0x0    R9:0x0   R10:0x0   R11:0x0   R12:0x0   R13:0x0   R14:0x0   R15:0x0
 ffffffff8a310600 ABI:2    AX:0x0    BX:0xffffffff8b8c39a0    CX:0x0    DX:0xffff8a2503890300    SI:0xffffb1690204ff20    DI:0xffff8a23e4080000    BP:0xffff8a23e4080000    SP:0xffffb1690204fec0    IP:0xffffffff8a310600 FLAGS:0x28e    CS:0x10    SS:0x18    R8:0x0    R9:0x0   R10:0x0   R11:0x0   R12:0xffffffffffffffea   R13:0xffff8a23e4080020   R14:0x0   R15:0x0
 ffffffff8a11b688 ABI:2    AX:0x0    BX:0xffff8a237b7c8800    CX:0xffffb1690204fae0    DX:0x78    SI:0xffff8a237b7c8800    DI:0xffffb1690204fa10    BP:0xffffb1690204fb00    SP:0xffffb1690204fa00    IP:0xffffffff8a11b688 FLAGS:0x8a    CS:0x10    SS:0x18    R8:0x1495f0a917eba    R9:0xffffd168fde19a48   R10:0xffffb1690204fd98   R11:0xffff8a253e82afb0   R12:0xffff8a237b7c8800   R13:0xffffb1690204fb00   R14:0x0   R15:0xffff8a237b7c8800
[root@five ~]#

To see it more clearly, lets get just two of those registers by sample:

  # perf record -a --intr-regs=ax,bx --user-regs=cx,dx sleep 1
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 3.502 MB perf.data (1653 samples) ]
  #

Extra info, lets see what gets setup in that 'struct perf_event_attr':

  # perf evlist -v
  cycles: size: 120, { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|CPU|PERIOD|REGS_USER|REGS_INTR, read_format: ID, disabled: 1, inherit: 1, mmap: 1, comm: 1, freq: 1, task: 1, precise_ip: 2, sample_id_all: 1, exclude_guest: 1, mmap2: 1, comm_exec: 1, ksymbol: 1, bpf_event: 1, sample_regs_user: 0xc, sample_regs_intr: 0x3
  #

Cook, some PERF_SAMPLE_REGS_USER|PERF_SAMPLE_REGS_INTR +
attr.sample_regs_user and attr.sample_regs_intr register masks, now lets
see if those newlines are gone in a more compact fashion:

  # perf script -Fip,iregs,uregs
   ffffffff8a56df78 ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a29b78d ABI:2    AX:0x2a20ffcd6000    BX:0x2ec7d9000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
  #

And where was that?

  # perf script -Fip,iregs,uregs,sym,dso
   ffffffff8a56df78 strrchr (/lib/modules/5.7.0-rc2/build/vmlinux) ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 strrchr (/lib/modules/5.7.0-rc2/build/vmlinux) ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 strrchr (/lib/modules/5.7.0-rc2/build/vmlinux) ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 strrchr (/lib/modules/5.7.0-rc2/build/vmlinux) ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 strrchr (/lib/modules/5.7.0-rc2/build/vmlinux) ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a56df78 strrchr (/lib/modules/5.7.0-rc2/build/vmlinux) ABI:2    AX:0xffff8a25137b6028    BX:0xffff8a2502f18000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
   ffffffff8a29b78d __vma_link_rb (/lib/modules/5.7.0-rc2/build/vmlinux) ABI:2    AX:0x2a20ffcd6000    BX:0x2ec7d9000  ABI:2    CX:0x7f204460e49b    DX:0xf42920
  #

Signed-off-by: Stephane Eranian <eranian@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Ian Rogers <irogers@google.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200418231908.152212-1-eranian@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf synthetic events: Remove use of sscanf from /proc reading
Ian Rogers [Wed, 15 Apr 2020 05:40:50 +0000 (22:40 -0700)]
perf synthetic events: Remove use of sscanf from /proc reading

The synthesize benchmark, run on a single process and thread, shows
perf_event__synthesize_mmap_events as the hottest function with fgets
and sscanf taking the majority of execution time.

fscanf performs similarly well. Replace the scanf call with manual
reading of each field of the /proc/pid/maps line, and remove some
unnecessary buffering.

This change also addresses potential, but unlikely, buffer overruns for
the string values read by scanf.

Performance before is:

  $ sudo perf bench internals synthesize -m 16 -M 16 -s -t
  \# Running 'internals/synthesize' benchmark:
  Computing performance of single threaded perf event synthesis by
  synthesizing events on the perf process itself:
    Average synthesis took: 102.810 usec (+- 0.027 usec)
    Average num. events: 17.000 (+- 0.000)
    Average time per event 6.048 usec
    Average data synthesis took: 106.325 usec (+- 0.018 usec)
    Average num. events: 89.000 (+- 0.000)
    Average time per event 1.195 usec
  Computing performance of multi threaded perf event synthesis by
  synthesizing events on CPU 0:
    Number of synthesis threads: 16
      Average synthesis took: 68103.100 usec (+- 441.234 usec)
      Average num. events: 30703.000 (+- 0.730)
      Average time per event 2.218 usec

And after is:

  $ sudo perf bench internals synthesize -m 16 -M 16 -s -t
  \# Running 'internals/synthesize' benchmark:
  Computing performance of single threaded perf event synthesis by
  synthesizing events on the perf process itself:
    Average synthesis took: 50.388 usec (+- 0.031 usec)
    Average num. events: 17.000 (+- 0.000)
    Average time per event 2.964 usec
    Average data synthesis took: 52.693 usec (+- 0.020 usec)
    Average num. events: 89.000 (+- 0.000)
    Average time per event 0.592 usec
  Computing performance of multi threaded perf event synthesis by
  synthesizing events on CPU 0:
    Number of synthesis threads: 16
      Average synthesis took: 45022.400 usec (+- 552.740 usec)
      Average num. events: 30624.200 (+- 10.037)
      Average time per event 1.470 usec

On a Intel Xeon 6154 compiling with Debian gcc 9.2.1.

Committer testing:

On a AMD Ryzen 5 3600X 6-Core Processor:

Before:

  # perf bench internals synthesize --min-threads 12 --max-threads 12 --st --mt
  # Running 'internals/synthesize' benchmark:
  Computing performance of single threaded perf event synthesis by
  synthesizing events on the perf process itself:
    Average synthesis took: 267.491 usec (+- 0.176 usec)
    Average num. events: 56.000 (+- 0.000)
    Average time per event 4.777 usec
    Average data synthesis took: 277.257 usec (+- 0.169 usec)
    Average num. events: 287.000 (+- 0.000)
    Average time per event 0.966 usec
  Computing performance of multi threaded perf event synthesis by
  synthesizing events on CPU 0:
    Number of synthesis threads: 12
      Average synthesis took: 81599.500 usec (+- 346.315 usec)
      Average num. events: 36096.100 (+- 2.523)
      Average time per event 2.261 usec
  #

After:

  # perf bench internals synthesize --min-threads 12 --max-threads 12 --st --mt
  # Running 'internals/synthesize' benchmark:
  Computing performance of single threaded perf event synthesis by
  synthesizing events on the perf process itself:
    Average synthesis took: 110.125 usec (+- 0.080 usec)
    Average num. events: 56.000 (+- 0.000)
    Average time per event 1.967 usec
    Average data synthesis took: 118.518 usec (+- 0.057 usec)
    Average num. events: 287.000 (+- 0.000)
    Average time per event 0.413 usec
  Computing performance of multi threaded perf event synthesis by
  synthesizing events on CPU 0:
    Number of synthesis threads: 12
      Average synthesis took: 43490.700 usec (+- 284.527 usec)
      Average num. events: 37028.500 (+- 0.563)
      Average time per event 1.175 usec
  #

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200415054050.31645-4-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agotools api: Add a lightweight buffered reading api
Ian Rogers [Wed, 15 Apr 2020 05:40:49 +0000 (22:40 -0700)]
tools api: Add a lightweight buffered reading api

The synthesize benchmark shows the majority of execution time going to
fgets and sscanf, necessary to parse /proc/pid/maps. Add a new buffered
reading library that will be used to replace these calls in a follow-up
CL. Add tests for the library to perf test.

Committer tests:

  $ perf test api
  63: Test api io                                           : Ok
  $

Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200415054050.31645-3-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf bench: Add a multi-threaded synthesize benchmark
Ian Rogers [Wed, 15 Apr 2020 05:40:48 +0000 (22:40 -0700)]
perf bench: Add a multi-threaded synthesize benchmark

By default this isn't run as it reads /proc and may not have access.
For consistency, modify the single threaded benchmark to compute an
average time per event.

Committer testing:

  $ grep -m1 "model name" /proc/cpuinfo
  model name : Intel(R) Core(TM) i7-8650U CPU @ 1.90GHz
  $ grep "model name" /proc/cpuinfo  | wc -l
  8
  $
  $ perf bench internals synthesize -h
  # Running 'internals/synthesize' benchmark:

   Usage: perf bench internals synthesize <options>

      -I, --multi-iterations <n>
                            Number of iterations used to compute multi-threaded average
      -i, --single-iterations <n>
                            Number of iterations used to compute single-threaded average
      -M, --max-threads <n>
                            Maximum number of threads in multithreaded bench
      -m, --min-threads <n>
                            Minimum number of threads in multithreaded bench
      -s, --st              Run single threaded benchmark
      -t, --mt              Run multi-threaded benchmark

  $
  $ perf bench internals synthesize -t
  # Running 'internals/synthesize' benchmark:
  Computing performance of multi threaded perf event synthesis by
  synthesizing events on CPU 0:
    Number of synthesis threads: 1
      Average synthesis took: 65449.000 usec (+- 586.442 usec)
      Average num. events: 9405.400 (+- 0.306)
      Average time per event 6.959 usec
    Number of synthesis threads: 2
      Average synthesis took: 37838.300 usec (+- 130.259 usec)
      Average num. events: 9501.800 (+- 20.469)
      Average time per event 3.982 usec
    Number of synthesis threads: 3
      Average synthesis took: 48551.400 usec (+- 225.686 usec)
      Average num. events: 9544.000 (+- 0.000)
      Average time per event 5.087 usec
    Number of synthesis threads: 4
      Average synthesis took: 29632.500 usec (+- 50.808 usec)
      Average num. events: 9544.000 (+- 0.000)
      Average time per event 3.105 usec
    Number of synthesis threads: 5
      Average synthesis took: 33920.400 usec (+- 284.509 usec)
      Average num. events: 9544.000 (+- 0.000)
      Average time per event 3.554 usec
    Number of synthesis threads: 6
      Average synthesis took: 27604.100 usec (+- 72.344 usec)
      Average num. events: 9548.000 (+- 0.000)
      Average time per event 2.891 usec
    Number of synthesis threads: 7
      Average synthesis took: 25406.300 usec (+- 933.371 usec)
      Average num. events: 9545.500 (+- 0.167)
      Average time per event 2.662 usec
    Number of synthesis threads: 8
      Average synthesis took: 24110.400 usec (+- 73.229 usec)
      Average num. events: 9551.000 (+- 0.000)
      Average time per event 2.524 usec
  $

Signed-off-by: Ian Rogers <irogers@google.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Acked-by: Namhyung Kim <namhyung@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andrey Zhizhikin <andrey.z@gmail.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Kefeng Wang <wangkefeng.wang@huawei.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Petr Mladek <pmladek@suse.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200415054050.31645-2-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf record: Add num-synthesize-threads option
Stephane Eranian [Wed, 22 Apr 2020 15:50:38 +0000 (08:50 -0700)]
perf record: Add num-synthesize-threads option

To control degree of parallelism of the synthesize_mmap() code which
is scanning /proc/PID/task/PID/maps and can be time consuming.
Mimic perf top way of handling the option.
If not specified will default to 1 thread, i.e. default behavior before
this option.

On a desktop computer the processing of /proc/PID/task/PID/maps isn't
slow enough to warrant parallel processing and the thread creation has
some cost - hence the default of 1. On a loaded server with
>100 cores it is possible to see synthesis times in the order of
seconds and in this case having the option is desirable.

As the processing is a synchronization point, it is legitimate to worry if
Amdahl's law will apply to this patch. Profiling with this patch in
place:
https://lore.kernel.org/lkml/20200415054050.31645-4-irogers@google.com/
shows:
...
      - 32.59% __perf_event__synthesize_threads
         - 32.54% __event__synthesize_thread
            + 22.13% perf_event__synthesize_mmap_events
            + 6.68% perf_event__get_comm_ids.constprop.0
            + 1.49% process_synthesized_event
            + 1.29% __GI___readdir64
            + 0.60% __opendir
...
That is the processing is 1.49% of execution time and there is plenty to
make parallel. This is shown in the benchmark in this patch:

https://lore.kernel.org/lkml/20200415054050.31645-2-irogers@google.com/

  Computing performance of multi threaded perf event synthesis by
  synthesizing events on CPU 0:
   Number of synthesis threads: 1
     Average synthesis took: 127729.000 usec (+- 3372.880 usec)
     Average num. events: 21548.600 (+- 0.306)
     Average time per event 5.927 usec
   Number of synthesis threads: 2
     Average synthesis took: 88863.500 usec (+- 385.168 usec)
     Average num. events: 21552.800 (+- 0.327)
     Average time per event 4.123 usec
   Number of synthesis threads: 3
     Average synthesis took: 83257.400 usec (+- 348.617 usec)
     Average num. events: 21553.200 (+- 0.327)
     Average time per event 3.863 usec
   Number of synthesis threads: 4
     Average synthesis took: 75093.000 usec (+- 422.978 usec)
     Average num. events: 21554.200 (+- 0.200)
     Average time per event 3.484 usec
   Number of synthesis threads: 5
     Average synthesis took: 64896.600 usec (+- 353.348 usec)
     Average num. events: 21558.000 (+- 0.000)
     Average time per event 3.010 usec
   Number of synthesis threads: 6
     Average synthesis took: 59210.200 usec (+- 342.890 usec)
     Average num. events: 21560.000 (+- 0.000)
     Average time per event 2.746 usec
   Number of synthesis threads: 7
     Average synthesis took: 54093.900 usec (+- 306.247 usec)
     Average num. events: 21562.000 (+- 0.000)
     Average time per event 2.509 usec
   Number of synthesis threads: 8
     Average synthesis took: 48938.700 usec (+- 341.732 usec)
     Average num. events: 21564.000 (+- 0.000)
     Average time per event 2.269 usec

Where average time per synthesized event goes from 5.927 usec with 1
thread to 2.269 usec with 8. This isn't a linear speed up as not all of
synthesize code has been made parallel. If the synthesis time was about
10 seconds then using 8 threads may bring this down to less than 4.

Signed-off-by: Stephane Eranian <eranian@google.com>
Reviewed-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Tony Jones <tonyj@suse.de>
Cc: yuzhoujian <yuzhoujian@didichuxing.com>
Link: http://lore.kernel.org/lkml/20200422155038.9380-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf test session topology: Fix data path
Tommi Rantala [Thu, 23 Apr 2020 11:53:40 +0000 (14:53 +0300)]
perf test session topology: Fix data path

Commit 2d4f27999b88 ("perf data: Add global path holder") missed path
conversion in tests/topology.c, causing the "Session topology" testcase
to "hang" (waits forever for input from stdin) when doing "ssh $VM perf
test".

Can be reproduced by running "cat | perf test topo", and crashed by
replacing cat with true:

  $ true | perf test -v topo
  40: Session topology                                      :
  --- start ---
  test child forked, pid 3638
  templ file: /tmp/perf-test-QPvAch
  incompatible file format
  incompatible file format (rerun with -v to learn more)
  free(): invalid pointer
  test child interrupted
  ---- end ----
  Session topology: FAILED!

Committer testing:

Reproduced the above result before the patch and after it is back
working:

  # true | perf test -v topo
  41: Session topology                                      :
  --- start ---
  test child forked, pid 19374
  templ file: /tmp/perf-test-YOTEQg
  CPU 0, core 0, socket 0
  CPU 1, core 1, socket 0
  CPU 2, core 2, socket 0
  CPU 3, core 3, socket 0
  CPU 4, core 0, socket 0
  CPU 5, core 1, socket 0
  CPU 6, core 2, socket 0
  CPU 7, core 3, socket 0
  test child finished with 0
  ---- end ----
  Session topology: Ok
  #

Fixes: 2d4f27999b88 ("perf data: Add global path holder")
Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mamatha Inamdar <mamatha4@linux.vnet.ibm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ravi Bangoria <ravi.bangoria@linux.ibm.com>
Link: http://lore.kernel.org/lkml/20200423115341.562782-1-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf stat: Improve runtime stat for interval mode
Jin Yao [Mon, 20 Apr 2020 14:54:17 +0000 (22:54 +0800)]
perf stat: Improve runtime stat for interval mode

For interval mode, the metric is printed after the '#' character if it
exists. But it's not calculated by the counts generated in this
interval.

See the following examples:

  root@kbl-ppc:~# perf stat -M CPI -I1000 --interval-count 2
  #           time             counts unit events
       1.000422803            764,809      inst_retired.any          #      2.9 CPI
       1.000422803          2,234,932      cycles
       2.001464585          1,960,061      inst_retired.any          #      1.6 CPI
       2.001464585          4,022,591      cycles

The second CPI should not be 1.6 (4,022,591/1,960,061 is 2.1)

  root@kbl-ppc:~# perf stat -e cycles,instructions -I1000 --interval-count 2
  #           time             counts unit events
       1.000429493          2,869,311      cycles
       1.000429493            816,875      instructions              #    0.28  insn per cycle
       2.001516426          9,260,973      cycles
       2.001516426          5,250,634      instructions              #    0.87  insn per cycle

The second 'insn per cycle' should not be 0.87 (5,250,634/9,260,973 is
0.57).

The current code uses a global variable 'rt_stat' for tracking and
updating the std dev of runtime stat. Unlike the counts, 'rt_stat' is not
reset for interval. While the counts are reset for interval.

  perf_stat_process_counter()
  {
          if (config->interval)
                  init_stats(ps->res_stats);
  }

So for interval mode, the 'rt_stat' variable should be reset too.

This patch resets 'rt_stat' before read_counters(), so the runtime stat
is only calculated by the counts generated in this interval.

With this patch:

  root@kbl-ppc:~# perf stat -M CPI -I1000 --interval-count 2
  #           time             counts unit events
       1.000420924          2,408,818      inst_retired.any          #      2.1 CPI
       1.000420924          5,010,111      cycles
       2.001448579          2,798,407      inst_retired.any          #      1.6 CPI
       2.001448579          4,599,861      cycles

  root@kbl-ppc:~# perf stat -e cycles,instructions -I1000 --interval-count 2
  #           time             counts unit events
       1.000428555          2,769,714      cycles
       1.000428555            774,462      instructions              #    0.28  insn per cycle
       2.001471562          3,595,904      cycles
       2.001471562          1,243,703      instructions              #    0.35  insn per cycle

Now the second 'insn per cycle' and CPI are calculated by the counts
generated in this interval.

Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-By: Kajol Jain <kjain@linux.ibm.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200420145417.6864-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf stat: Zero all the 'ena' and 'run' array slot stats for interval mode
Jin Yao [Thu, 9 Apr 2020 07:07:55 +0000 (15:07 +0800)]
perf stat: Zero all the 'ena' and 'run' array slot stats for interval mode

As the code comments in perf_stat_process_counter() say, we calculate
counter's data every interval, and the display code shows ps->res_stats
avg value. We need to zero the stats for interval mode.

But the current code only zeros the res_stats[0], it doesn't zero the
res_stats[1] and res_stats[2], which are for ena and run of counter.

This patch zeros the whole res_stats[] for interval mode.

Fixes: 51fd2df1e882 ("perf stat: Fix interval output values")
Signed-off-by: Jin Yao <yao.jin@linux.intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jin Yao <yao.jin@intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200409070755.17261-1-yao.jin@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf script: Avoid NULL dereference on symbol
Ian Rogers [Tue, 21 Apr 2020 00:43:29 +0000 (17:43 -0700)]
perf script: Avoid NULL dereference on symbol

al->sym may be NULL given current if conditions and may cause a segv.

Fixes: d2bedb7863e9 ("perf script: Allow --symbol to accept hexadecimal addresses")
Signed-off-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Link: http://lore.kernel.org/lkml/20200421004329.43109-1-irogers@google.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf evlist: Remove duplicate headers
Jagadeesh Pagadala [Sun, 19 Apr 2020 06:13:56 +0000 (11:43 +0530)]
perf evlist: Remove duplicate headers

Code cleanup: Remove duplicate headers which are included twice.

Signed-off-by: Jagadeesh Pagadala <jagdsh.linux@gmail.com>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Link: http://lore.kernel.org/lkml/1587276836-17088-1-git-send-email-jagdsh.linux@gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf bench: Fix div-by-zero if runtime is zero
Tommi Rantala [Fri, 17 Apr 2020 13:23:29 +0000 (16:23 +0300)]
perf bench: Fix div-by-zero if runtime is zero

Fix div-by-zero if runtime is zero:

  $ perf bench futex hash --runtime=0
  # Running 'futex/hash' benchmark:
  Run summary [PID 12090]: 4 threads, each operating on 1024 [private] futexes for 0 secs.
  Floating point exception (core dumped)

Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Darren Hart <dvhart@infradead.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lore.kernel.org/lkml/20200417132330.119407-4-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoperf cgroup: Avoid needless closing of unopened fd
Tommi Rantala [Fri, 17 Apr 2020 13:23:26 +0000 (16:23 +0300)]
perf cgroup: Avoid needless closing of unopened fd

Do not bother with close() if fd is not valid, just to silence valgrind:

    $ valgrind ./perf script
    ==59169== Memcheck, a memory error detector
    ==59169== Copyright (C) 2002-2017, and GNU GPL'd, by Julian Seward et al.
    ==59169== Using Valgrind-3.14.0 and LibVEX; rerun with -h for copyright info
    ==59169== Command: ./perf script
    ==59169==
    ==59169== Warning: invalid file descriptor -1 in syscall close()
    ==59169== Warning: invalid file descriptor -1 in syscall close()
    ==59169== Warning: invalid file descriptor -1 in syscall close()
    ==59169== Warning: invalid file descriptor -1 in syscall close()
    ==59169== Warning: invalid file descriptor -1 in syscall close()
    ==59169== Warning: invalid file descriptor -1 in syscall close()
    ==59169== Warning: invalid file descriptor -1 in syscall close()
    ==59169== Warning: invalid file descriptor -1 in syscall close()

Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lore.kernel.org/lkml/20200417132330.119407-1-tommi.t.rantala@nokia.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
4 years agoMerge tag 'perf-core-for-mingo-5.8-20200420' of git://git.kernel.org/pub/scm/linux...
Ingo Molnar [Wed, 22 Apr 2020 12:08:28 +0000 (14:08 +0200)]
Merge tag 'perf-core-for-mingo-5.8-20200420' of git://git./linux/kernel/git/acme/linux into perf/core

Pull perf/core fixes and improvements from Arnaldo Carvalho de Melo:

kernel + tools/perf:

  Alexey Budankov:

  - Introduce CAP_PERFMON to kernel and user space.

callchains:

  Adrian Hunter:

  - Allow using Intel PT to synthesize callchains for regular events.

  Kan Liang:

  - Stitch LBR records from multiple samples to get deeper backtraces,
    there are caveats, see the csets for details.

perf script:

  Andreas Gerstmayr:

  - Add flamegraph.py script

BPF:

  Jiri Olsa:

  - Synthesize bpf_trampoline/dispatcher ksymbol events.

perf stat:

  Arnaldo Carvalho de Melo:

  - Honour --timeout for forked workloads.

  Stephane Eranian:

  - Force error in fallback on :k events, to avoid counting nothing when
    the user asks for kernel events but is not allowed to.

perf bench:

  Ian Rogers:

  - Add event synthesis benchmark.

tools api fs:

  Stephane Eranian:

 - Make xxx__mountpoint() more scalable

libtraceevent:

  He Zhe:

  - Handle return value of asprintf.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
4 years agoMerge branch 'akpm' (patches from Andrew)
Linus Torvalds [Tue, 21 Apr 2020 20:26:54 +0000 (13:26 -0700)]
Merge branch 'akpm' (patches from Andrew)

Merge misc fixes from Andrew Morton:
 "15 fixes"

* emailed patches from Andrew Morton <akpm@linux-foundation.org>:
  tools/vm: fix cross-compile build
  coredump: fix null pointer dereference on coredump
  mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path
  shmem: fix possible deadlocks on shmlock_user_lock
  vmalloc: fix remap_vmalloc_range() bounds checks
  mm/shmem: fix build without THP
  mm/ksm: fix NULL pointer dereference when KSM zero page is enabled
  tools/build: tweak unused value workaround
  checkpatch: fix a typo in the regex for $allocFunctions
  mm, gup: return EINTR when gup is interrupted by fatal signals
  mm/hugetlb: fix a addressing exception caused by huge_pte_offset
  MAINTAINERS: add an entry for kfifo
  mm/userfaultfd: disable userfaultfd-wp on x86_32
  slub: avoid redzone when choosing freepointer location
  sh: fix build error in mm/init.c

4 years agoMerge tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm
Linus Torvalds [Tue, 21 Apr 2020 19:59:10 +0000 (12:59 -0700)]
Merge tag 'for-linus' of git://git./virt/kvm/kvm

Pull kvm fixes from Paolo Bonzini:
 "Bugfixes, and a few cleanups to the newly-introduced assembly language
  vmentry code for AMD"

* tag 'for-linus' of git://git.kernel.org/pub/scm/virt/kvm/kvm:
  KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions
  kvm: Disable objtool frame pointer checking for vmenter.S
  MAINTAINERS: add a reviewer for KVM/s390
  KVM: s390: Fix PV check in deliverable_irqs()
  kvm: Handle reads of SandyBridge RAPL PMU MSRs rather than injecting #GP
  KVM: Remove CREATE_IRQCHIP/SET_PIT2 race
  KVM: SVM: Fix __svm_vcpu_run declaration.
  KVM: SVM: Do not setup frame pointer in __svm_vcpu_run
  KVM: SVM: Fix build error due to missing release_pages() include
  KVM: SVM: Do not mark svm_vcpu_run with STACK_FRAME_NON_STANDARD
  kvm: nVMX: match comment with return type for nested_vmx_exit_reflected
  kvm: nVMX: reflect MTF VM-exits if injected by L1
  KVM: s390: Return last valid slot if approx index is out-of-bounds
  KVM: Check validity of resolved slot when searching memslots
  KVM: VMX: Enable machine check support for 32bit targets
  KVM: SVM: move more vmentry code to assembly
  KVM: SVM: fix compilation with modular PSP and non-modular KVM

4 years agoMerge tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost
Linus Torvalds [Tue, 21 Apr 2020 19:27:18 +0000 (12:27 -0700)]
Merge tag 'for_linus' of git://git./linux/kernel/git/mst/vhost

Pull virtio fixes and cleanups from Michael Tsirkin:

 - Some bug fixes

 - Cleanup a couple of issues that surfaced meanwhile

 - Disable vhost on ARM with OABI for now - to be fixed fully later in
   the cycle or in the next release.

* tag 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mst/vhost: (24 commits)
  vhost: disable for OABI
  virtio: drop vringh.h dependency
  virtio_blk: add a missing include
  virtio-balloon: Avoid using the word 'report' when referring to free page hinting
  virtio-balloon: make virtballoon_free_page_report() static
  vdpa: fix comment of vdpa_register_device()
  vdpa: make vhost, virtio depend on menu
  vdpa: allow a 32 bit vq alignment
  drm/virtio: fix up for include file changes
  remoteproc: pull in slab.h
  rpmsg: pull in slab.h
  virtio_input: pull in slab.h
  remoteproc: pull in slab.h
  virtio-rng: pull in slab.h
  virtgpu: pull in uaccess.h
  tools/virtio: make asm/barrier.h self contained
  tools/virtio: define aligned attribute
  virtio/test: fix up after IOTLB changes
  vhost: Create accessors for virtqueues private_data
  vdpasim: Return status in vdpasim_get_status
  ...

4 years agoMerge tag 'tpmdd-next-20200421' of git://git.infradead.org/users/jjs/linux-tpmdd
Linus Torvalds [Tue, 21 Apr 2020 19:24:33 +0000 (12:24 -0700)]
Merge tag 'tpmdd-next-20200421' of git://git.infradead.org/users/jjs/linux-tpmdd

Pull tpm fixes from Jarkko Sakkinen:
 "A few bug fixes"

* tag 'tpmdd-next-20200421' of git://git.infradead.org/users/jjs/linux-tpmdd:
  tpm/tpm_tis: Free IRQ if probing fails
  tpm: fix wrong return value in tpm_pcr_extend
  tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()
  tpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module

4 years agoMerge tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux
Linus Torvalds [Tue, 21 Apr 2020 19:07:42 +0000 (12:07 -0700)]
Merge tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux

Pull clang-format fixlets from Miguel Ojeda:
 "Two trivial clang-format changes:

   - Don't indent C++ namespaces (Ian Rogers)

   - The usual clang-format macro list update (Miguel Ojeda)"

* tag 'clang-format-for-linus-v5.7-rc3' of git://github.com/ojeda/linux:
  clang-format: Update with the latest for_each macro list
  clang-format: don't indent namespaces

4 years agotools/vm: fix cross-compile build
Lucas Stach [Tue, 21 Apr 2020 01:14:23 +0000 (18:14 -0700)]
tools/vm: fix cross-compile build

Commit 7ed1c1901fe5 ("tools: fix cross-compile var clobbering") moved
the setup of the CC variable to tools/scripts/Makefile.include to make
the behavior consistent across all the tools Makefiles.

As the vm tools missed the include we end up with the wrong CC in a
cross-compiling evironment.

Fixes: 7ed1c1901fe5 (tools: fix cross-compile var clobbering)
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Martin Kelly <martin@martingkelly.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416104748.25243-1-l.stach@pengutronix.de
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocoredump: fix null pointer dereference on coredump
Sudip Mukherjee [Tue, 21 Apr 2020 01:14:20 +0000 (18:14 -0700)]
coredump: fix null pointer dereference on coredump

If the core_pattern is set to "|" and any process segfaults then we get
a null pointer derefernce while trying to coredump. The call stack shows:

    RIP: do_coredump+0x628/0x11c0

When the core_pattern has only "|" there is no use of trying the
coredump and we can check that while formating the corename and exit
with an error.

After this change I get:

    format_corename failed
    Aborting core

Fixes: 315c69261dd3 ("coredump: split pipe command whitespace before expanding template")
Reported-by: Matthew Ruffell <matthew.ruffell@canonical.com>
Signed-off-by: Sudip Mukherjee <sudipm.mukherjee@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Paul Wise <pabs3@bonedaddy.net>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Neil Horman <nhorman@tuxdriver.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416194612.21418-1-sudipm.mukherjee@gmail.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path
Yang Shi [Tue, 21 Apr 2020 01:14:17 +0000 (18:14 -0700)]
mm: shmem: disable interrupt when acquiring info->lock in userfaultfd_copy path

Syzbot reported the below lockdep splat:

    WARNING: possible irq lock inversion dependency detected
    5.6.0-rc7-syzkaller #0 Not tainted
    --------------------------------------------------------
    syz-executor.0/10317 just changed the state of lock:
    ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: spin_lock include/linux/spinlock.h:338 [inline]
    ffff888021d16568 (&(&info->lock)->rlock){+.+.}, at: shmem_mfill_atomic_pte+0x1012/0x21c0 mm/shmem.c:2407
    but this lock was taken by another, SOFTIRQ-safe lock in the past:
     (&(&xa->xa_lock)->rlock#5){..-.}

    and interrupts could create inverse lock ordering between them.

    other info that might help us debug this:
     Possible interrupt unsafe locking scenario:

           CPU0                    CPU1
           ----                    ----
      lock(&(&info->lock)->rlock);
                                   local_irq_disable();
                                   lock(&(&xa->xa_lock)->rlock#5);
                                   lock(&(&info->lock)->rlock);
      <Interrupt>
        lock(&(&xa->xa_lock)->rlock#5);

     *** DEADLOCK ***

The full report is quite lengthy, please see:

  https://lore.kernel.org/linux-mm/alpine.LSU.2.11.2004152007370.13597@eggly.anvils/T/#m813b412c5f78e25ca8c6c7734886ed4de43f241d

It is because CPU 0 held info->lock with IRQ enabled in userfaultfd_copy
path, then CPU 1 is splitting a THP which held xa_lock and info->lock in
IRQ disabled context at the same time.  If softirq comes in to acquire
xa_lock, the deadlock would be triggered.

The fix is to acquire/release info->lock with *_irq version instead of
plain spin_{lock,unlock} to make it softirq safe.

Fixes: 4c27fe4c4c84 ("userfaultfd: shmem: add shmem_mcopy_atomic_pte for userfaultfd support")
Reported-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com
Signed-off-by: Yang Shi <yang.shi@linux.alibaba.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: syzbot+e27980339d305f2dbfd9@syzkaller.appspotmail.com
Acked-by: Hugh Dickins <hughd@google.com>
Cc: Andrea Arcangeli <aarcange@redhat.com>
Link: http://lkml.kernel.org/r/1587061357-122619-1-git-send-email-yang.shi@linux.alibaba.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoshmem: fix possible deadlocks on shmlock_user_lock
Hugh Dickins [Tue, 21 Apr 2020 01:14:14 +0000 (18:14 -0700)]
shmem: fix possible deadlocks on shmlock_user_lock

Recent commit 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page()
when punching hole") has allowed syzkaller to probe deeper, uncovering a
long-standing lockdep issue between the irq-unsafe shmlock_user_lock,
the irq-safe xa_lock on mapping->i_pages, and shmem inode's info->lock
which nests inside xa_lock (or tree_lock) since 4.8's shmem_uncharge().

user_shm_lock(), servicing SysV shmctl(SHM_LOCK), wants
shmlock_user_lock while its caller shmem_lock() holds info->lock with
interrupts disabled; but hugetlbfs_file_setup() calls user_shm_lock()
with interrupts enabled, and might be interrupted by a writeback endio
wanting xa_lock on i_pages.

This may not risk an actual deadlock, since shmem inodes do not take
part in writeback accounting, but there are several easy ways to avoid
it.

Requiring interrupts disabled for shmlock_user_lock would be easy, but
it's a high-level global lock for which that seems inappropriate.
Instead, recall that the use of info->lock to guard info->flags in
shmem_lock() dates from pre-3.1 days, when races with SHMEM_PAGEIN and
SHMEM_TRUNCATE could occur: nowadays it serves no purpose, the only flag
added or removed is VM_LOCKED itself, and calls to shmem_lock() an inode
are already serialized by the caller.

Take info->lock out of the chain and the possibility of deadlock or
lockdep warning goes away.

Fixes: 4595ef88d136 ("shmem: make shmem_inode_info::lock irq-safe")
Reported-by: syzbot+c8a8197c8852f566b9d9@syzkaller.appspotmail.com
Reported-by: syzbot+40b71e145e73f78f81ad@syzkaller.appspotmail.com
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004161707410.16322@eggly.anvils
Link: https://lore.kernel.org/lkml/000000000000e5838c05a3152f53@google.com/
Link: https://lore.kernel.org/lkml/0000000000003712b305a331d3b1@google.com/
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agovmalloc: fix remap_vmalloc_range() bounds checks
Jann Horn [Tue, 21 Apr 2020 01:14:11 +0000 (18:14 -0700)]
vmalloc: fix remap_vmalloc_range() bounds checks

remap_vmalloc_range() has had various issues with the bounds checks it
promises to perform ("This function checks that addr is a valid
vmalloc'ed area, and that it is big enough to cover the vma") over time,
e.g.:

 - not detecting pgoff<<PAGE_SHIFT overflow

 - not detecting (pgoff<<PAGE_SHIFT)+usize overflow

 - not checking whether addr and addr+(pgoff<<PAGE_SHIFT) are the same
   vmalloc allocation

 - comparing a potentially wildly out-of-bounds pointer with the end of
   the vmalloc region

In particular, since commit fc9702273e2e ("bpf: Add mmap() support for
BPF_MAP_TYPE_ARRAY"), unprivileged users can cause kernel null pointer
dereferences by calling mmap() on a BPF map with a size that is bigger
than the distance from the start of the BPF map to the end of the
address space.

This could theoretically be used as a kernel ASLR bypass, by using
whether mmap() with a given offset oopses or returns an error code to
perform a binary search over the possible address range.

To allow remap_vmalloc_range_partial() to verify that addr and
addr+(pgoff<<PAGE_SHIFT) are in the same vmalloc region, pass the offset
to remap_vmalloc_range_partial() instead of adding it to the pointer in
remap_vmalloc_range().

In remap_vmalloc_range_partial(), fix the check against
get_vm_area_size() by using size comparisons instead of pointer
comparisons, and add checks for pgoff.

Fixes: 833423143c3a ("[PATCH] mm: introduce remap_vmalloc_range()")
Signed-off-by: Jann Horn <jannh@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: stable@vger.kernel.org
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Cc: Martin KaFai Lau <kafai@fb.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Yonghong Song <yhs@fb.com>
Cc: Andrii Nakryiko <andriin@fb.com>
Cc: John Fastabend <john.fastabend@gmail.com>
Cc: KP Singh <kpsingh@chromium.org>
Link: http://lkml.kernel.org/r/20200415222312.236431-1-jannh@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/shmem: fix build without THP
Hugh Dickins [Tue, 21 Apr 2020 01:14:07 +0000 (18:14 -0700)]
mm/shmem: fix build without THP

Some optimizers don't notice that shmem_punch_compound() is always true
(PageTransCompound() being false) without CONFIG_TRANSPARENT_HUGEPAGE==y.

Use IS_ENABLED to help them to avoid the BUILD_BUG inside HPAGE_PMD_NR.

Fixes: 71725ed10c40 ("mm: huge tmpfs: try to split_huge_page() when punching hole")
Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Randy Dunlap <rdunlap@infradead.org>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: http://lkml.kernel.org/r/alpine.LSU.2.11.2004142339170.10035@eggly.anvils
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/ksm: fix NULL pointer dereference when KSM zero page is enabled
Muchun Song [Tue, 21 Apr 2020 01:14:04 +0000 (18:14 -0700)]
mm/ksm: fix NULL pointer dereference when KSM zero page is enabled

find_mergeable_vma() can return NULL.  In this case, it leads to a crash
when we access vm_mm(its offset is 0x40) later in write_protect_page.
And this case did happen on our server.  The following call trace is
captured in kernel 4.19 with the following patch applied and KSM zero
page enabled on our server.

  commit e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring")

So add a vma check to fix it.

  BUG: unable to handle kernel NULL pointer dereference at 0000000000000040
  Oops: 0000 [#1] SMP NOPTI
  CPU: 9 PID: 510 Comm: ksmd Kdump: loaded Tainted: G OE 4.19.36.bsk.9-amd64 #4.19.36.bsk.9
  RIP: try_to_merge_one_page+0xc7/0x760
  Code: 24 58 65 48 33 34 25 28 00 00 00 89 e8 0f 85 a3 06 00 00 48 83 c4
        60 5b 5d 41 5c 41 5d 41 5e 41 5f c3 48 8b 46 08 a8 01 75 b8 <49>
        8b 44 24 40 4c 8d 7c 24 20 b9 07 00 00 00 4c 89 e6 4c 89 ff 48
  RSP: 0018:ffffadbdd9fffdb0 EFLAGS: 00010246
  RAX: ffffda83ffd4be08 RBX: ffffda83ffd4be40 RCX: 0000002c6e800000
  RDX: 0000000000000000 RSI: ffffda83ffd4be40 RDI: 0000000000000000
  RBP: ffffa11939f02ec0 R08: 0000000094e1a447 R09: 00000000abe76577
  R10: 0000000000000962 R11: 0000000000004e6a R12: 0000000000000000
  R13: ffffda83b1e06380 R14: ffffa18f31f072c0 R15: ffffda83ffd4be40
  FS: 0000000000000000(0000) GS:ffffa0da43b80000(0000) knlGS:0000000000000000
  CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
  CR2: 0000000000000040 CR3: 0000002c77c0a003 CR4: 00000000007626e0
  DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
  DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
  PKRU: 55555554
  Call Trace:
    ksm_scan_thread+0x115e/0x1960
    kthread+0xf5/0x130
    ret_from_fork+0x1f/0x30

[songmuchun@bytedance.com: if the vma is out of date, just exit]
Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com
[akpm@linux-foundation.org: add the conventional braces, replace /** with /*]
Fixes: e86c59b1b12d ("mm/ksm: improve deduplication of zero pages with colouring")
Co-developed-by: Xiongchun Duan <duanxiongchun@bytedance.com>
Signed-off-by: Muchun Song <songmuchun@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Reviewed-by: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Yang Shi <yang.shi@linux.alibaba.com>
Cc: Claudio Imbrenda <imbrenda@linux.vnet.ibm.com>
Cc: Markus Elfring <Markus.Elfring@web.de>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200416025034.29780-1-songmuchun@bytedance.com
Link: http://lkml.kernel.org/r/20200414132905.83819-1-songmuchun@bytedance.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agotools/build: tweak unused value workaround
George Burgess IV [Tue, 21 Apr 2020 01:14:01 +0000 (18:14 -0700)]
tools/build: tweak unused value workaround

Clang has -Wself-assign enabled by default under -Wall, which always
gets -Werror'ed on this file, causing sync-compare-and-swap to be
disabled by default.

The generally-accepted way to spell "this value is intentionally
unused," is casting it to `void`.  This is accepted by both GCC and
Clang with -Wall enabled: https://godbolt.org/z/qqZ9r3

Signed-off-by: George Burgess IV <gbiv@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Nick Desaulniers <ndesaulniers@google.com>
Link: http://lkml.kernel.org/r/20200414195638.156123-1-gbiv@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agocheckpatch: fix a typo in the regex for $allocFunctions
Christophe JAILLET [Tue, 21 Apr 2020 01:13:58 +0000 (18:13 -0700)]
checkpatch: fix a typo in the regex for $allocFunctions

Here, we look for function such as 'netdev_alloc_skb_ip_align', so a '_'
is missing in the regex.

To make sure:
   grep -r --include=*.c skbip_a * | wc   ==>   0 results
   grep -r --include=*.c skb_ip_a * | wc  ==> 112 results

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Joe Perches <joe@perches.com>
Link: http://lkml.kernel.org/r/20200407190029.892-1-christophe.jaillet@wanadoo.fr
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm, gup: return EINTR when gup is interrupted by fatal signals
Michal Hocko [Tue, 21 Apr 2020 01:13:55 +0000 (18:13 -0700)]
mm, gup: return EINTR when gup is interrupted by fatal signals

EINTR is the usual error code which other killable interfaces return.
This is the case for the other fatal_signal_pending break out from the
same function.  Make the code consistent.

ERESTARTSYS is also quite confusing because the signal is fatal and so
no restart will happen before returning to the userspace.

Signed-off-by: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Xu <peterx@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: http://lkml.kernel.org/r/20200409071133.31734-1-mhocko@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/hugetlb: fix a addressing exception caused by huge_pte_offset
Longpeng [Tue, 21 Apr 2020 01:13:51 +0000 (18:13 -0700)]
mm/hugetlb: fix a addressing exception caused by huge_pte_offset

Our machine encountered a panic(addressing exception) after run for a
long time and the calltrace is:

    RIP: hugetlb_fault+0x307/0xbe0
    RSP: 0018:ffff9567fc27f808  EFLAGS: 00010286
    RAX: e800c03ff1258d48 RBX: ffffd3bb003b69c0 RCX: e800c03ff1258d48
    RDX: 17ff3fc00eda72b7 RSI: 00003ffffffff000 RDI: e800c03ff1258d48
    RBP: ffff9567fc27f8c8 R08: e800c03ff1258d48 R09: 0000000000000080
    R10: ffffaba0704c22a8 R11: 0000000000000001 R12: ffff95c87b4b60d8
    R13: 00005fff00000000 R14: 0000000000000000 R15: ffff9567face8074
    FS:  00007fe2d9ffb700(0000) GS:ffff956900e40000(0000) knlGS:0000000000000000
    CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
    CR2: ffffd3bb003b69c0 CR3: 000000be67374000 CR4: 00000000003627e0
    DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
    DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
    Call Trace:
      follow_hugetlb_page+0x175/0x540
      __get_user_pages+0x2a0/0x7e0
      __get_user_pages_unlocked+0x15d/0x210
      __gfn_to_pfn_memslot+0x3c5/0x460 [kvm]
      try_async_pf+0x6e/0x2a0 [kvm]
      tdp_page_fault+0x151/0x2d0 [kvm]
     ...
      kvm_arch_vcpu_ioctl_run+0x330/0x490 [kvm]
      kvm_vcpu_ioctl+0x309/0x6d0 [kvm]
      do_vfs_ioctl+0x3f0/0x540
      SyS_ioctl+0xa1/0xc0
      system_call_fastpath+0x22/0x27

For 1G hugepages, huge_pte_offset() wants to return NULL or pudp, but it
may return a wrong 'pmdp' if there is a race.  Please look at the
following code snippet:

    ...
    pud = pud_offset(p4d, addr);
    if (sz != PUD_SIZE && pud_none(*pud))
        return NULL;
    /* hugepage or swap? */
    if (pud_huge(*pud) || !pud_present(*pud))
        return (pte_t *)pud;

    pmd = pmd_offset(pud, addr);
    if (sz != PMD_SIZE && pmd_none(*pmd))
        return NULL;
    /* hugepage or swap? */
    if (pmd_huge(*pmd) || !pmd_present(*pmd))
        return (pte_t *)pmd;
    ...

The following sequence would trigger this bug:

 - CPU0: sz = PUD_SIZE and *pud = 0 , continue
 - CPU0: "pud_huge(*pud)" is false
 - CPU1: calling hugetlb_no_page and set *pud to xxxx8e7(PRESENT)
 - CPU0: "!pud_present(*pud)" is false, continue
 - CPU0: pmd = pmd_offset(pud, addr) and maybe return a wrong pmdp

However, we want CPU0 to return NULL or pudp in this case.

We must make sure there is exactly one dereference of pud and pmd.

Signed-off-by: Longpeng <longpeng2@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Reviewed-by: Jason Gunthorpe <jgg@mellanox.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: <stable@vger.kernel.org>
Link: http://lkml.kernel.org/r/20200413010342.771-1-longpeng2@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoMAINTAINERS: add an entry for kfifo
Bartosz Golaszewski [Tue, 21 Apr 2020 01:13:48 +0000 (18:13 -0700)]
MAINTAINERS: add an entry for kfifo

Kfifo has been written by Stefani Seibold and she's implicitly expected
to Ack any changes to it.  She's not however officially listed as kfifo
maintainer which leads to delays in patch review.  This patch proposes
to add an explitic entry for kfifo to MAINTAINERS file.

[akpm@linux-foundation.org: alphasort F: entries, per Joe]
[akpm@linux-foundation.org: remove colon, per Bartosz]
Link: http://lkml.kernel.org/r/20200124174533.21815-1-brgl@bgdev.pl
Link: http://lkml.kernel.org/r/20200413104250.26683-1-brgl@bgdev.pl
Signed-off-by: Bartosz Golaszewski <bgolaszewski@baylibre.com>
Acked-by: Stefani Seibold <stefani@seibold.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: Joe Perches <joe@perches.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agomm/userfaultfd: disable userfaultfd-wp on x86_32
Peter Xu [Tue, 21 Apr 2020 01:13:45 +0000 (18:13 -0700)]
mm/userfaultfd: disable userfaultfd-wp on x86_32

Userfaultfd-wp is not yet working on 32bit hosts, but it's accidentally
enabled previously.  Disable it.

Fixes: 5a281062af1d ("userfaultfd: wp: add WP pagetable tracking to x86")
Reported-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Peter Xu <peterx@redhat.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Naresh Kamboju <naresh.kamboju@linaro.org>
Reviewed-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: Hillf Danton <hdanton@sina.com>
Link: http://lkml.kernel.org/r/20200413141608.109211-1-peterx@redhat.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoslub: avoid redzone when choosing freepointer location
Kees Cook [Tue, 21 Apr 2020 01:13:42 +0000 (18:13 -0700)]
slub: avoid redzone when choosing freepointer location

Marco Elver reported system crashes when booting with "slub_debug=Z".

The freepointer location (s->offset) was not taking into account that
the "inuse" size that includes the redzone area should not be used by
the freelist pointer.  Change the calculation to save the area of the
object that an inline freepointer may be written into.

Fixes: 3202fa62fb43 ("slub: relocate freelist pointer to middle of object")
Reported-by: Marco Elver <elver@google.com>
Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Tested-by: Marco Elver <elver@google.com>
Cc: Christoph Lameter <cl@linux.com>
Cc: Pekka Enberg <penberg@kernel.org>
Cc: David Rientjes <rientjes@google.com>
Cc: Joonsoo Kim <iamjoonsoo.kim@lge.com>
Link: http://lkml.kernel.org/r/202004151054.BD695840@keescook
Link: https://lore.kernel.org/linux-mm/20200415164726.GA234932@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agosh: fix build error in mm/init.c
Masahiro Yamada [Tue, 21 Apr 2020 01:13:38 +0000 (18:13 -0700)]
sh: fix build error in mm/init.c

The closing parenthesis is missing.

Fixes: bfeb022f8fe4 ("mm/memory_hotplug: add pgprot_t to mhp_params")
Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Geert Uytterhoeven <geert+renesas@glider.be>
Reviewed-by: Logan Gunthorpe <logang@deltatee.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Cc: Guenter Roeck <linux@roeck-us.net>
Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: Rich Felker <dalias@libc.org>
Link: http://lkml.kernel.org/r/20200413014743.16353-1-masahiroy@kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoMerge tag 'kvm-ppc-fixes-5.7-1' of git://git.kernel.org/pub/scm/linux/kernel/git...
Paolo Bonzini [Tue, 21 Apr 2020 13:39:55 +0000 (09:39 -0400)]
Merge tag 'kvm-ppc-fixes-5.7-1' of git://git./linux/kernel/git/paulus/powerpc into kvm-master

PPC KVM fix for 5.7

- Fix a regression introduced in the last merge window, which results
  in guests in HPT mode dying randomly.

4 years agoMerge tag 'kvm-s390-master-5.7-2' of git://git.kernel.org/pub/scm/linux/kernel/git...
Paolo Bonzini [Tue, 21 Apr 2020 13:37:13 +0000 (09:37 -0400)]
Merge tag 'kvm-s390-master-5.7-2' of git://git./linux/kernel/git/kvms390/linux into kvm-master

KVM: s390: Fix for 5.7 and maintainer update

- Silence false positive lockdep warning
- add Claudio as reviewer

4 years agoKVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions
Paul Mackerras [Thu, 16 Apr 2020 04:23:43 +0000 (14:23 +1000)]
KVM: PPC: Book3S HV: Handle non-present PTEs in page fault functions

Since cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT
page fault handler", it's been possible in fairly rare circumstances to
load a non-present PTE in kvmppc_book3s_hv_page_fault() when running a
guest on a POWER8 host.

Because that case wasn't checked for, we could misinterpret the non-present
PTE as being a cache-inhibited PTE.  That could mismatch with the
corresponding hash PTE, which would cause the function to fail with -EFAULT
a little further down.  That would propagate up to the KVM_RUN ioctl()
generally causing the KVM userspace (usually qemu) to fall over.

This addresses the problem by catching that case and returning to the guest
instead.

For completeness, this fixes the radix page fault handler in the same
way.  For radix this didn't cause any obvious misbehaviour, because we
ended up putting the non-present PTE into the guest's partition-scoped
page tables, leading immediately to another hypervisor data/instruction
storage interrupt, which would go through the page fault path again
and fix things up.

Fixes: cd758a9b57ee "KVM: PPC: Book3S HV: Use __gfn_to_pfn_memslot in HPT page fault handler"
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=1820402
Reported-by: David Gibson <david@gibson.dropbear.id.au>
Tested-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Paul Mackerras <paulus@ozlabs.org>
4 years agokvm: Disable objtool frame pointer checking for vmenter.S
Josh Poimboeuf [Mon, 20 Apr 2020 16:17:37 +0000 (11:17 -0500)]
kvm: Disable objtool frame pointer checking for vmenter.S

Frame pointers are completely broken by vmenter.S because it clobbers
RBP:

  arch/x86/kvm/svm/vmenter.o: warning: objtool: __svm_vcpu_run()+0xe4: BP used as a scratch register

That's unavoidable, so just skip checking that file when frame pointers
are configured in.

On the other hand, ORC can handle that code just fine, so leave objtool
enabled in the !FRAME_POINTER case.

Reported-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Message-Id: <01fae42917bacad18be8d2cbc771353da6603473.1587398610.git.jpoimboe@redhat.com>
Tested-by: Randy Dunlap <rdunlap@infradead.org> # build-tested
Fixes: 199cd1d7b534 ("KVM: SVM: Split svm_vcpu_run inline assembly to separate file")
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
4 years agotpm/tpm_tis: Free IRQ if probing fails
Jarkko Sakkinen [Sun, 12 Apr 2020 17:04:12 +0000 (20:04 +0300)]
tpm/tpm_tis: Free IRQ if probing fails

Call disable_interrupts() if we have to revert to polling in order not to
unnecessarily reserve the IRQ for the life-cycle of the driver.

Cc: stable@vger.kernel.org # 4.5.x
Reported-by: Hans de Goede <hdegoede@redhat.com>
Fixes: e3837e74a06d ("tpm_tis: Refactor the interrupt setup")
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
4 years agotpm: fix wrong return value in tpm_pcr_extend
Tianjia Zhang [Tue, 14 Apr 2020 11:42:26 +0000 (19:42 +0800)]
tpm: fix wrong return value in tpm_pcr_extend

For the algorithm that does not match the bank, a positive
value EINVAL is returned here. I think this is a typo error.
It is necessary to return an error value.

Cc: stable@vger.kernel.org # 5.4.x
Fixes: 9f75c8224631 ("KEYS: trusted: correctly initialize digests and fix locking issue")
Signed-off-by: Tianjia Zhang <tianjia.zhang@linux.alibaba.com>
Reviewed-by: Roberto Sassu <roberto.sassu@huawei.com>
Reviewed-by: Jerry Snitselaar <jsnitsel@redhat.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
4 years agotpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()
George Wilson [Fri, 20 Mar 2020 03:27:58 +0000 (23:27 -0400)]
tpm: ibmvtpm: retry on H_CLOSED in tpm_ibmvtpm_send()

tpm_ibmvtpm_send() can fail during PowerVM Live Partition Mobility resume
with an H_CLOSED return from ibmvtpm_send_crq().  The PAPR says, 'The
"partner partition suspended" transport event disables the associated CRQ
such that any H_SEND_CRQ hcall() to the associated CRQ returns H_Closed
until the CRQ has been explicitly enabled using the H_ENABLE_CRQ hcall.'
This patch adds a check in tpm_ibmvtpm_send() for an H_CLOSED return from
ibmvtpm_send_crq() and in that case calls tpm_ibmvtpm_resume() and
retries the ibmvtpm_send_crq() once.

Cc: stable@vger.kernel.org # 3.7.x
Fixes: 132f76294744 ("drivers/char/tpm: Add new device driver to support IBM vTPM")
Reported-by: Linh Pham <phaml@us.ibm.com>
Reviewed-by: Stefan Berger <stefanb@linux.ibm.com>
Signed-off-by: George Wilson <gcwilson@linux.ibm.com>
Tested-by: Linh Pham <phaml@us.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
4 years agotpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module
Stefan Berger [Thu, 19 Mar 2020 01:00:17 +0000 (21:00 -0400)]
tpm: Export tpm2_get_cc_attrs_tbl for ibmvtpm driver as module

This patch fixes the following problem when the ibmvtpm driver
is built as a module:

ERROR: modpost: "tpm2_get_cc_attrs_tbl" [drivers/char/tpm/tpm_ibmvtpm.ko] undefined!
make[1]: *** [scripts/Makefile.modpost:94: __modpost] Error 1
make: *** [Makefile:1298: modules] Error 2

Fixes: 18b3670d79ae ("tpm: ibmvtpm: Add support for TPM2")
Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
Reported-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.vnet.ibm.com>
Reviewed-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
4 years agovhost: disable for OABI
Michael S. Tsirkin [Mon, 6 Apr 2020 12:12:47 +0000 (08:12 -0400)]
vhost: disable for OABI

vhost is currently broken on the some ARM configs.

The reason is that the ring element addresses are passed between
components with different alignments assumptions. Thus, if
guest selects a pointer and host then gets and dereferences
it, then alignment assumed by the host's compiler might be
greater than the actual alignment of the pointer.
compiler on the host from assuming pointer is aligned.

This actually triggers on ARM with -mabi=apcs-gnu - which is a
deprecated configuration. With this OABI, compiler assumes that
all structures are 4 byte aligned - which is stronger than
virtio guarantees for available and used rings, which are
merely 2 bytes. Thus a guest without -mabi=apcs-gnu running
on top of host with -mabi=apcs-gnu will be broken.

The correct fix is to force alignment of structures - however
that is an intrusive fix that's best deferred until the next release.

We didn't previously support such ancient systems at all - this surfaced
after vdpa support prompted removing dependency of vhost on
VIRTULIZATION. So for now, let's just add something along the lines of

depends on !ARM || AEABI

to the virtio Kconfig declaration, and add a comment that it has to do
with struct member alignment.

Note: we can't make VHOST and VHOST_RING themselves have
a dependency since these are selected. Add a new symbol for that.

We should be able to drop this dependency down the road.

Fixes: 20c384f1ea1a0bc7 ("vhost: refine vhost and vringh kconfig")
Suggested-by: Ard Biesheuvel <ardb@kernel.org>
Suggested-by: Richard Earnshaw <Richard.Earnshaw@arm.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
4 years agoMAINTAINERS: add a reviewer for KVM/s390
Claudio Imbrenda [Fri, 17 Apr 2020 15:29:36 +0000 (17:29 +0200)]
MAINTAINERS: add a reviewer for KVM/s390

Signed-off-by: Claudio Imbrenda <imbrenda@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Janosch Frank <frankja@linux.ibm.com>
Link: https://lore.kernel.org/r/20200417152936.772256-1-imbrenda@linux.ibm.com
4 years agoKVM: s390: Fix PV check in deliverable_irqs()
Eric Farman [Wed, 15 Apr 2020 19:03:53 +0000 (21:03 +0200)]
KVM: s390: Fix PV check in deliverable_irqs()

The diag 0x44 handler, which handles a directed yield, goes into a
a codepath that does a kvm_for_each_vcpu() and ultimately
deliverable_irqs().  The new check for kvm_s390_pv_cpu_is_protected()
contains an assertion that the vcpu->mutex is held, which isn't going
to be the case in this scenario.

The result is a plethora of these messages if the lock debugging
is enabled, and thus an implication that we have a problem.

  WARNING: CPU: 9 PID: 16167 at arch/s390/kvm/kvm-s390.h:239 deliverable_irqs+0x1c6/0x1d0 [kvm]
  ...snip...
  Call Trace:
   [<000003ff80429bf2>] deliverable_irqs+0x1ca/0x1d0 [kvm]
  ([<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm])
   [<000003ff8042ba82>] kvm_s390_vcpu_has_irq+0x2a/0xa8 [kvm]
   [<000003ff804101e2>] kvm_arch_dy_runnable+0x22/0x38 [kvm]
   [<000003ff80410284>] kvm_vcpu_on_spin+0x8c/0x1d0 [kvm]
   [<000003ff80436888>] kvm_s390_handle_diag+0x3b0/0x768 [kvm]
   [<000003ff80425af4>] kvm_handle_sie_intercept+0x1cc/0xcd0 [kvm]
   [<000003ff80422bb0>] __vcpu_run+0x7b8/0xfd0 [kvm]
   [<000003ff80423de6>] kvm_arch_vcpu_ioctl_run+0xee/0x3e0 [kvm]
   [<000003ff8040ccd8>] kvm_vcpu_ioctl+0x2c8/0x8d0 [kvm]
   [<00000001504ced06>] ksys_ioctl+0xae/0xe8
   [<00000001504cedaa>] __s390x_sys_ioctl+0x2a/0x38
   [<0000000150cb9034>] system_call+0xd8/0x2d8
  2 locks held by CPU 2/KVM/16167:
   #0: 00000001951980c0 (&vcpu->mutex){+.+.}, at: kvm_vcpu_ioctl+0x90/0x8d0 [kvm]
   #1: 000000019599c0f0 (&kvm->srcu){....}, at: __vcpu_run+0x4bc/0xfd0 [kvm]
  Last Breaking-Event-Address:
   [<000003ff80429b34>] deliverable_irqs+0x10c/0x1d0 [kvm]
  irq event stamp: 11967
  hardirqs last  enabled at (11975): [<00000001502992f2>] console_unlock+0x4ca/0x650
  hardirqs last disabled at (11982): [<0000000150298ee8>] console_unlock+0xc0/0x650
  softirqs last  enabled at (7940): [<0000000150cba6ca>] __do_softirq+0x422/0x4d8
  softirqs last disabled at (7929): [<00000001501cd688>] do_softirq_own_stack+0x70/0x80

Considering what's being done here, let's fix this by removing the
mutex assertion rather than acquiring the mutex for every other vcpu.

Fixes: 201ae986ead7 ("KVM: s390: protvirt: Implement interrupt injection")
Signed-off-by: Eric Farman <farman@linux.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Link: https://lore.kernel.org/r/20200415190353.63625-1-farman@linux.ibm.com
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
4 years agoLinux 5.7-rc2
Linus Torvalds [Sun, 19 Apr 2020 21:35:30 +0000 (14:35 -0700)]
Linux 5.7-rc2

4 years agomm: Fix MREMAP_DONTUNMAP accounting on VMA merge
Brian Geffon [Fri, 17 Apr 2020 17:25:56 +0000 (10:25 -0700)]
mm: Fix MREMAP_DONTUNMAP accounting on VMA merge

When remapping a mapping where a portion of a VMA is remapped
into another portion of the VMA it can cause the VMA to become
split. During the copy_vma operation the VMA can actually
be remerged if it's an anonymous VMA whose pages have not yet
been faulted. This isn't normally a problem because at the end
of the remap the original portion is unmapped causing it to
become split again.

However, MREMAP_DONTUNMAP leaves that original portion in place which
means that the VMA which was split and then remerged is not actually
split at the end of the mremap. This patch fixes a bug where
we don't detect that the VMAs got remerged and we end up
putting back VM_ACCOUNT on the next mapping which is completely
unreleated. When that next mapping is unmapped it results in
incorrectly unaccounting for the memory which was never accounted,
and eventually we will underflow on the memory comittment.

There is also another issue which is similar, we're currently
accouting for the number of pages in the new_vma but that's wrong.
We need to account for the length of the remap operation as that's
all that is being added. If there was a mapping already at that
location its comittment would have been adjusted as part of
the munmap at the start of the mremap.

A really simple repro can be seen in:
https://gist.github.com/bgaff/e101ce99da7d9a8c60acc641d07f312c

Fixes: e346b3813067 ("mm/mremap: add MREMAP_DONTUNMAP to mremap()")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Brian Geffon <bgeffon@google.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
4 years agoMerge tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 19 Apr 2020 20:59:06 +0000 (13:59 -0700)]
Merge tag 'clk-fixes-for-linus' of git://git./linux/kernel/git/clk/linux

Pull clk fixes from Stephen Boyd:
 "Two build fixes for a couple clk drivers and a fix for the Unisoc
  serial clk where we want to keep it on for earlycon"

* tag 'clk-fixes-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/clk/linux:
  clk: sprd: don't gate uart console clock
  clk: mmp2: fix link error without mmp2
  clk: asm9260: fix __clk_hw_register_fixed_rate_with_accuracy typo

4 years agoMerge tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 19 Apr 2020 18:58:32 +0000 (11:58 -0700)]
Merge tag 'x86-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip

Pull x86 and objtool fixes from Thomas Gleixner:
 "A set of fixes for x86 and objtool:

  objtool:

   - Ignore the double UD2 which is emitted in BUG() when
     CONFIG_UBSAN_TRAP is enabled.

   - Support clang non-section symbols in objtool ORC dump

   - Fix switch table detection in .text.unlikely

   - Make the BP scratch register warning more robust.

  x86:

   - Increase microcode maximum patch size for AMD to cope with new CPUs
     which have a larger patch size.

   - Fix a crash in the resource control filesystem when the removal of
     the default resource group is attempted.

   - Preserve Code and Data Prioritization enabled state accross CPU
     hotplug.

   - Update split lock cpu matching to use the new X86_MATCH macros.

   - Change the split lock enumeration as Intel finaly decided that the
     IA32_CORE_CAPABILITIES bits are not architectural contrary to what
     the SDM claims. !@#%$^!

   - Add Tremont CPU models to the split lock detection cpu match.

   - Add a missing static attribute to make sparse happy"

* tag 'x86-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  x86/split_lock: Add Tremont family CPU models
  x86/split_lock: Bits in IA32_CORE_CAPABILITIES are not architectural
  x86/resctrl: Preserve CDP enable over CPU hotplug
  x86/resctrl: Fix invalid attempt at removing the default resource group
  x86/split_lock: Update to use X86_MATCH_INTEL_FAM6_MODEL()
  x86/umip: Make umip_insns static
  x86/microcode/AMD: Increase microcode PATCH_MAX_SIZE
  objtool: Make BP scratch register warning more robust
  objtool: Fix switch table detection in .text.unlikely
  objtool: Support Clang non-section symbols in ORC generation
  objtool: Support Clang non-section symbols in ORC dump
  objtool: Fix CONFIG_UBSAN_TRAP unreachable warnings

4 years agoMerge tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 19 Apr 2020 18:46:21 +0000 (11:46 -0700)]
Merge tag 'timers-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip

Pull time namespace fix from Thomas Gleixner:
 "An update for the proc interface of time namespaces: Use symbolic
  names instead of clockid numbers. The usability nuisance of numbers
  was noticed by Michael when polishing the man page"

* tag 'timers-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  proc, time/namespace: Show clock symbolic names in /proc/pid/timens_offsets

4 years agoMerge tag 'perf-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 19 Apr 2020 18:28:01 +0000 (11:28 -0700)]
Merge tag 'perf-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip

Pull perf tooling fixes and updates from Thomas Gleixner:

 - Fix the header line of perf stat output for '--metric-only --per-socket'

 - Fix the python build with clang

 - The usual tools UAPI header synchronization

* tag 'perf-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  tools headers: Synchronize linux/bits.h with the kernel sources
  tools headers: Adopt verbatim copy of compiletime_assert() from kernel sources
  tools headers: Update x86's syscall_64.tbl with the kernel sources
  tools headers UAPI: Sync drm/i915_drm.h with the kernel sources
  tools headers UAPI: Update tools's copy of drm.h headers
  tools headers kvm: Sync linux/kvm.h with the kernel sources
  tools headers UAPI: Sync linux/fscrypt.h with the kernel sources
  tools include UAPI: Sync linux/vhost.h with the kernel sources
  tools arch x86: Sync asm/cpufeatures.h with the kernel sources
  tools headers UAPI: Sync linux/mman.h with the kernel
  tools headers UAPI: Sync sched.h with the kernel
  tools headers: Update linux/vdso.h and grab a copy of vdso/const.h
  perf stat: Fix no metric header if --per-socket and --metric-only set
  perf python: Check if clang supports -fno-semantic-interposition
  tools arch x86: Sync the msr-index.h copy with the kernel sources

4 years agoMerge tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 19 Apr 2020 18:23:33 +0000 (11:23 -0700)]
Merge tag 'irq-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:
 "A set of fixes/updates for the interrupt subsystem:

   - Remove setup_irq() and remove_irq(). All users have been converted
     so remove them before new users surface.

   - A set of bugfixes for various interrupt chip drivers

   - Add a few missing static attributes to address sparse warnings"

* tag 'irq-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqchip/irq-bcm7038-l1: Make bcm7038_l1_of_init() static
  irqchip/irq-mvebu-icu: Make legacy_bindings static
  irqchip/meson-gpio: Fix HARDIRQ-safe -> HARDIRQ-unsafe lock order
  irqchip/sifive-plic: Fix maximum priority threshold value
  irqchip/ti-sci-inta: Fix processing of masked irqs
  irqchip/mbigen: Free msi_desc on device teardown
  irqchip/gic-v4.1: Update effective affinity of virtual SGIs
  irqchip/gic-v4.1: Add support for VPENDBASER's Dirty+Valid signaling
  genirq: Remove setup_irq() and remove_irq()

4 years agoMerge tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel...
Linus Torvalds [Sun, 19 Apr 2020 18:18:20 +0000 (11:18 -0700)]
Merge tag 'sched-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip

Pull scheduler fixes from Thomas Gleixner:
 "Two fixes for the scheduler:

   - Work around an uninitialized variable warning where GCC can't
     figure it out.

   - Allow 'isolcpus=' to skip unknown subparameters so that older
     kernels work with the commandline of a newer kernel. Improve the
     error output while at it"

* tag 'sched-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  sched/vtime: Work around an unitialized variable warning
  sched/isolation: Allow "isolcpus=" to skip unknown sub-parameters

4 years agoMerge tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 19 Apr 2020 18:16:00 +0000 (11:16 -0700)]
Merge tag 'core-urgent-2020-04-19' of git://git./linux/kernel/git/tip/tip

Pull RCU fix from Thomas Gleixner:
 "A single bugfix for RCU to prevent taking a lock in NMI context"

* tag 'core-urgent-2020-04-19' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  rcu: Don't acquire lock in NMI handler in rcu_nmi_enter_common()

4 years agoMerge tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git...
Linus Torvalds [Sun, 19 Apr 2020 18:05:15 +0000 (11:05 -0700)]
Merge tag 'ext4_for_linus_stable' of git://git./linux/kernel/git/tytso/ext4

Pull ext4 fixes from Ted Ts'o:
 "Miscellaneous bug fixes and cleanups for ext4, including a fix for
  generic/388 in data=journal mode, removing some BUG_ON's, and cleaning
  up some compiler warnings"

* tag 'ext4_for_linus_stable' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/ext4:
  ext4: convert BUG_ON's to WARN_ON's in mballoc.c
  ext4: increase wait time needed before reuse of deleted inode numbers
  ext4: remove set but not used variable 'es' in ext4_jbd2.c
  ext4: remove set but not used variable 'es'
  ext4: do not zeroout extents beyond i_disksize
  ext4: fix return-value types in several function comments
  ext4: use non-movable memory for superblock readahead
  ext4: use matching invalidatepage in ext4_writepage

4 years agoMerge tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6
Linus Torvalds [Sun, 19 Apr 2020 18:00:27 +0000 (11:00 -0700)]
Merge tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6

Pull cifs fixes from Steve French:
 "Three small smb3 fixes: two debug related (helping network tracing for
  SMB2 mounts, and the other removing an unintended debug line on
  signing failures), and one fixing a performance problem with 64K
  pages"

* tag '5.7-rc-smb3-fixes' of git://git.samba.org/sfrench/cifs-2.6:
  smb3: remove overly noisy debug line in signing errors
  cifs: improve read performance for page size 64KB & cache=strict & vers=2.1+
  cifs: dump the session id and keys also for SMB2 sessions

4 years agoMerge tag 'flexible-array-member-5.7-rc2' of git://git.kernel.org/pub/scm/linux/kerne...
Linus Torvalds [Sun, 19 Apr 2020 17:34:30 +0000 (10:34 -0700)]
Merge tag 'flexible-array-member-5.7-rc2' of git://git./linux/kernel/git/gustavoars/linux

Pull flexible-array member conversion from Gustavo Silva:
 "The current codebase makes use of the zero-length array language
  extension to the C90 standard, but the preferred mechanism to declare
  variable-length types such as these ones is a flexible array
  member[1][2], introduced in C99:

    struct foo {
        int stuff;
        struct boo array[];
    };

  By making use of the mechanism above, we will get a compiler warning
  in case the flexible array does not occur last in the structure, which
  will help us prevent some kind of undefined behavior bugs from being
  inadvertently introduced[3] to the codebase from now on.

  Also, notice that, dynamic memory allocations won't be affected by
  this change:

   "Flexible array members have incomplete type, and so the sizeof
    operator may not be applied. As a quirk of the original
    implementation of zero-length arrays, sizeof evaluates to zero."[1]

  sizeof(flexible-array-member) triggers a warning because flexible
  array members have incomplete type[1]. There are some instances of
  code in which the sizeof operator is being incorrectly/erroneously
  applied to zero-length arrays and the result is zero. Such instances
  may be hiding some bugs. So, this work (flexible-array member
  convertions) will also help to get completely rid of those sorts of
  issues.

  Notice that all of these patches have been baking in linux-next for
  quite a while now and, 238 more of these patches have already been
  merged into 5.7-rc1.

  There are a couple hundred more of these issues waiting to be
  addressed in the whole codebase"

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

* tag 'flexible-array-member-5.7-rc2' of git://git.kernel.org/pub/scm/linux/kernel/git/gustavoars/linux: (28 commits)
  xattr.h: Replace zero-length array with flexible-array member
  uapi: linux: fiemap.h: Replace zero-length array with flexible-array member
  uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
  tpm_eventlog.h: Replace zero-length array with flexible-array member
  ti_wilink_st.h: Replace zero-length array with flexible-array member
  swap.h: Replace zero-length array with flexible-array member
  skbuff.h: Replace zero-length array with flexible-array member
  sched: topology.h: Replace zero-length array with flexible-array member
  rslib.h: Replace zero-length array with flexible-array member
  rio.h: Replace zero-length array with flexible-array member
  posix_acl.h: Replace zero-length array with flexible-array member
  platform_data: wilco-ec.h: Replace zero-length array with flexible-array member
  memcontrol.h: Replace zero-length array with flexible-array member
  list_lru.h: Replace zero-length array with flexible-array member
  lib: cpu_rmap: Replace zero-length array with flexible-array member
  irq.h: Replace zero-length array with flexible-array member
  ihex.h: Replace zero-length array with flexible-array member
  igmp.h: Replace zero-length array with flexible-array member
  genalloc.h: Replace zero-length array with flexible-array member
  ethtool.h: Replace zero-length array with flexible-array member
  ...

4 years agoMerge tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi
Linus Torvalds [Sat, 18 Apr 2020 21:03:12 +0000 (14:03 -0700)]
Merge tag 'scsi-fixes' of git://git./linux/kernel/git/jejb/scsi

Pull SCSI fixes from James Bottomley:
 "Seven fixes: three in target, one on a sg error leg, two in qla2xxx
  fixing warnings introduced in the last merge window and updating
  MAINTAINERS and one in hisi_sas fixing a problem introduced by libata"

* tag 'scsi-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi:
  scsi: sg: add sg_remove_request in sg_common_write
  scsi: target: tcmu: reset_ring should reset TCMU_DEV_BIT_BROKEN
  scsi: target: fix PR IN / READ FULL STATUS for FC
  scsi: target: Write NULL to *port_nexus_ptr if no ISID
  scsi: MAINTAINERS: Update qla2xxx FC-SCSI driver maintainer
  scsi: qla2xxx: Fix regression warnings
  scsi: hisi_sas: Fix build error without SATA_HOST

4 years agoxattr.h: Replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:41:14 +0000 (19:41 -0500)]
xattr.h: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
4 years agouapi: linux: fiemap.h: Replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 24 Mar 2020 02:30:22 +0000 (21:30 -0500)]
uapi: linux: fiemap.h: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>
4 years agouapi: linux: dlm_device.h: Replace zero-length array with flexible-array member
Gustavo A. R. Silva [Tue, 24 Mar 2020 00:51:46 +0000 (19:51 -0500)]
uapi: linux: dlm_device.h: Replace zero-length array with flexible-array member

The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com>