Docs: admin/kernel-parameters: edit a few boot options
authorRandy Dunlap <rdunlap@infradead.org>
Sun, 3 Apr 2022 05:48:20 +0000 (22:48 -0700)
committerJonathan Corbet <corbet@lwn.net>
Sat, 16 Apr 2022 08:49:04 +0000 (02:49 -0600)
Clean up some of admin-guide/kernel-parameters.txt:

a. "smt" should be "smt=" (S390)
b. (dropped)
c. Sparc supports the vdso= boot option
d. make the tp_printk options (2) formatting similar to other options
   by adding spacing
e. add "trace_clock=" with a reference to Documentation/trace/ftrace.rst
f. use [IA-64] as documented instead of [ia64]
g. fix formatting and text for test_suspend=
h. fix formatting for swapaccount=
i. fix formatting and grammar for video.brightness_switch_enabled=

Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Cc: Heiko Carstens <hca@linux.ibm.com>
Cc: Vasily Gorbik <gor@linux.ibm.com>
Cc: Alexander Gordeev <agordeev@linux.ibm.com>
Cc: Christian Borntraeger <borntraeger@linux.ibm.com>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: linux-s390@vger.kernel.org
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: sparclinux@vger.kernel.org
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: linux-ia64@vger.kernel.org
Cc: "Rafael J. Wysocki" <rafael@kernel.org>
Cc: Pavel Machek <pavel@ucw.cz>
Cc: Len Brown <lenb@kernel.org>
Cc: linux-pm@vger.kernel.org
Cc: linux-acpi@vger.kernel.org
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: linux-doc@vger.kernel.org
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Signed-off-by: Jonathan Corbet <corbet@lwn.net>
Documentation/admin-guide/kernel-parameters.txt

index 1e023ba..d524ad2 100644 (file)
                        different yeeloong laptops.
                        Example: machtype=lemote-yeeloong-2f-7inch
 
-       max_addr=nn[KMG]        [KNL,BOOT,ia64] All physical memory greater
+       max_addr=nn[KMG]        [KNL,BOOT,IA-64] All physical memory greater
                        than or equal to this physical address is ignored.
 
        maxcpus=        [SMP] Maximum number of processors that an SMP kernel
 
        mga=            [HW,DRM]
 
-       min_addr=nn[KMG]        [KNL,BOOT,ia64] All physical memory below this
+       min_addr=nn[KMG]        [KNL,BOOT,IA-64] All physical memory below this
                        physical address is ignored.
 
        mini2440=       [ARM,HW,KNL]
                                1: Fast pin select (default)
                                2: ATC IRMode
 
-       smt             [KNL,S390] Set the maximum number of threads (logical
+       smt=            [KNL,S390] Set the maximum number of threads (logical
                        CPUs) to use per physical CPU on systems capable of
                        symmetric multithreading (SMT). Will be capped to the
                        actual hardware limit.
                        This parameter controls use of the Protected
                        Execution Facility on pSeries.
 
-       swapaccount=[0|1]
-                       [KNL] Enable accounting of swap in memory resource
+       swapaccount=    [KNL]
+                       Format: [0|1]
+                       Enable accounting of swap in memory resource
                        controller if no parameter or 1 is given or disable
                        it if 0 is given (See Documentation/admin-guide/cgroup-v1/memory.rst)
 
 
        tdfx=           [HW,DRM]
 
-       test_suspend=   [SUSPEND][,N]
+       test_suspend=   [SUSPEND]
+                       Format: { "mem" | "standby" | "freeze" }[,N]
                        Specify "mem" (for Suspend-to-RAM) or "standby" (for
                        standby suspend) or "freeze" (for suspend type freeze)
                        as the system sleep state during system startup with
        trace_buf_size=nn[KMG]
                        [FTRACE] will set tracing buffer size on each cpu.
 
+       trace_clock=    [FTRACE] Set the clock used for tracing events
+                       at boot up.
+                       local - Use the per CPU time stamp counter
+                               (converted into nanoseconds). Fast, but
+                               depending on the architecture, may not be
+                               in sync between CPUs.
+                       global - Event time stamps are synchronize across
+                               CPUs. May be slower than the local clock,
+                               but better for some race conditions.
+                       counter - Simple counting of events (1, 2, ..)
+                               note, some counts may be skipped due to the
+                               infrastructure grabbing the clock more than
+                               once per event.
+                       uptime - Use jiffies as the time stamp.
+                       perf - Use the same clock that perf uses.
+                       mono - Use ktime_get_mono_fast_ns() for time stamps.
+                       mono_raw - Use ktime_get_raw_fast_ns() for time
+                               stamps.
+                       boot - Use ktime_get_boot_fast_ns() for time stamps.
+                       Architectures may add more clocks. See
+                       Documentation/trace/ftrace.rst for more details.
+
        trace_event=[event-list]
                        [FTRACE] Set and start specified trace events in order
                        to facilitate early boot debugging. The event-list is a
                        See also Documentation/trace/ftrace.rst "trace options"
                        section.
 
-       tp_printk[FTRACE]
+       tp_printk       [FTRACE]
                        Have the tracepoints sent to printk as well as the
                        tracing ring buffer. This is useful for early boot up
                        where the system hangs or reboots and does not give the
                        frequency tracepoints such as irq or sched, can cause
                        the system to live lock.
 
-       tp_printk_stop_on_boot[FTRACE]
+       tp_printk_stop_on_boot [FTRACE]
                        When tp_printk (above) is set, it can cause a lot of noise
                        on the console. It may be useful to only include the
                        printing of events during boot up, as user space may
                                        HIGHMEM regardless of setting
                                        of CONFIG_HIGHPTE.
 
-       vdso=           [X86,SH]
+       vdso=           [X86,SH,SPARC]
                        On X86_32, this is an alias for vdso32=.  Otherwise:
 
                        vdso=1: enable VDSO (the default)
        video=          [FB] Frame buffer configuration
                        See Documentation/fb/modedb.rst.
 
-       video.brightness_switch_enabled= [0,1]
+       video.brightness_switch_enabled= [ACPI]
+                       Format: [0|1]
                        If set to 1, on receiving an ACPI notify event
                        generated by hotkey, video driver will adjust brightness
                        level and then send out the event to user space through
-                       the allocated input device; If set to 0, video driver
+                       the allocated input device. If set to 0, video driver
                        will only send out the event without touching backlight
                        brightness level.
                        default: 1