Commit Graph

60 Commits

Author SHA1 Message Date
Linus Torvalds b72b5fecc1 tracing updates for 6.3:
- Add function names as a way to filter function addresses
 
 - Add sample module to test ftrace ops and dynamic trampolines
 
 - Allow stack traces to be passed from beginning event to end event for
   synthetic events. This will allow seeing the stack trace of when a task is
   scheduled out and recorded when it gets scheduled back in.
 
 - Add trace event helper __get_buf() to use as a temporary buffer when printing
   out trace event output.
 
 - Add kernel command line to create trace instances on boot up.
 
 - Add enabling of events to instances created at boot up.
 
 - Add trace_array_puts() to write into instances.
 
 - Allow boot instances to take a snapshot at the end of boot up.
 
 - Allow live patch modules to include trace events
 
 - Minor fixes and clean ups
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Merge tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace

Pull tracing updates from Steven Rostedt:

 - Add function names as a way to filter function addresses

 - Add sample module to test ftrace ops and dynamic trampolines

 - Allow stack traces to be passed from beginning event to end event for
   synthetic events. This will allow seeing the stack trace of when a
   task is scheduled out and recorded when it gets scheduled back in.

 - Add trace event helper __get_buf() to use as a temporary buffer when
   printing out trace event output.

 - Add kernel command line to create trace instances on boot up.

 - Add enabling of events to instances created at boot up.

 - Add trace_array_puts() to write into instances.

 - Allow boot instances to take a snapshot at the end of boot up.

 - Allow live patch modules to include trace events

 - Minor fixes and clean ups

* tag 'trace-v6.3' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: (31 commits)
  tracing: Remove unnecessary NULL assignment
  tracepoint: Allow livepatch module add trace event
  tracing: Always use canonical ftrace path
  tracing/histogram: Fix stacktrace histogram Documententation
  tracing/histogram: Fix stacktrace key
  tracing/histogram: Fix a few problems with stacktrace variable printing
  tracing: Add BUILD_BUG() to make sure stacktrace fits in strings
  tracing/histogram: Don't use strlen to find length of stacktrace variables
  tracing: Allow boot instances to have snapshot buffers
  tracing: Add trace_array_puts() to write into instance
  tracing: Add enabling of events to boot instances
  tracing: Add creation of instances at boot command line
  tracing: Fix trace_event_raw_event_synth() if else statement
  samples: ftrace: Make some global variables static
  ftrace: sample: avoid open-coded 64-bit division
  samples: ftrace: Include the nospec-branch.h only for x86
  tracing: Acquire buffer from temparary trace sequence
  tracing/histogram: Wrap remaining shell snippets in code blocks
  tracing/osnoise: No need for schedule_hrtimeout range
  bpf/tracing: Use stage6 of tracing to not duplicate macros
  ...
2023-02-23 10:20:49 -08:00
Ross Zwisler 2455f0e124 tracing: Always use canonical ftrace path
The canonical location for the tracefs filesystem is at /sys/kernel/tracing.

But, from Documentation/trace/ftrace.rst:

  Before 4.1, all ftrace tracing control files were within the debugfs
  file system, which is typically located at /sys/kernel/debug/tracing.
  For backward compatibility, when mounting the debugfs file system,
  the tracefs file system will be automatically mounted at:

  /sys/kernel/debug/tracing

Many comments and Kconfig help messages in the tracing code still refer
to this older debugfs path, so let's update them to avoid confusion.

Link: https://lore.kernel.org/linux-trace-kernel/20230215223350.2658616-2-zwisler@google.com

Acked-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Mukesh Ojha <quic_mojha@quicinc.com>
Signed-off-by: Ross Zwisler <zwisler@google.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-18 14:34:09 -05:00
Daniel Bristot de Oliveira 1f428356c3 rtla: Add hwnoise tool
The hwnoise tool is a special mode for the osnoise top tool.

hwnoise dispatches the osnoise tracer and displays a summary of the noise.
The difference is that it runs the tracer with the OSNOISE_IRQ_DISABLE
option set, thus only allowing only hardware-related noise, resulting in
a simplified output. hwnoise has the same features of osnoise.

An example of the tool's output:

 # rtla hwnoise -c 1-11 -T 1 -d 10m -q
                                           Hardware-related Noise
 duration:   0 00:10:00 | time is in us
 CPU Period       Runtime        Noise  % CPU Aval   Max Noise   Max Single          HW          NMI
   1 #599       599000000          138    99.99997           3            3           4           74
   2 #599       599000000           85    99.99998           3            3           4           75
   3 #599       599000000           86    99.99998           4            3           6           75
   4 #599       599000000           81    99.99998           4            4           2           75
   5 #599       599000000           85    99.99998           2            2           2           75

Link: https://lkml.kernel.org/r/2d6f49a6f3a4f8b51b2c806458b1cff71ad4d014.1675805361.git.bristot@kernel.org

Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: Bagas Sanjaya <bagasdotme@gmail.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-13 23:56:46 -05:00
Daniel Bristot de Oliveira 5def33df84 rtla/timerlat: Add auto-analysis support to timerlat top
Currently, timerlat top displays the timerlat tracer latency results, saving
the intuitive timerlat trace for the developer to analyze.

This patch goes a step forward in the automaton of the scheduling latency
analysis by providing a summary of the root cause of a latency higher than
the passed "stop tracing" parameter if the trace stops.

The output is intuitive enough for non-expert users to have a general idea
of the root cause by looking at each factor's contribution percentage while
keeping the technical detail in the output for more expert users to start
an in dept debug or to correlate a root cause with an existing one.

The terminology is in line with recent industry and academic publications
to facilitate the understanding of both audiences.

Here is one example of tool output:
 ----------------------------------------- %< -----------------------------------------------------
  # taskset -c 0 timerlat -a 40 -c 1-23 -q
                                     Timer Latency
    0 00:00:12   |          IRQ Timer Latency (us)        |         Thread Timer Latency (us)
  CPU COUNT      |      cur       min       avg       max |      cur       min       avg       max
    1 #12322     |        0         0         1        15 |       10         3         9        31
    2 #12322     |        3         0         1        12 |       10         3         9        23
    3 #12322     |        1         0         1        21 |        8         2         8        34
    4 #12322     |        1         0         1        17 |       10         2        11        33
    5 #12322     |        0         0         1        12 |        8         3         8        25
    6 #12322     |        1         0         1        14 |       16         3        11        35
    7 #12322     |        0         0         1        14 |        9         2         8        29
    8 #12322     |        1         0         1        22 |        9         3         9        34
    9 #12322     |        0         0         1        14 |        8         2         8        24
   10 #12322     |        1         0         0        12 |        9         3         8        24
   11 #12322     |        0         0         0        15 |        6         2         7        29
   12 #12321     |        1         0         0        13 |        5         3         8        23
   13 #12319     |        0         0         1        14 |        9         3         9        26
   14 #12321     |        1         0         0        13 |        6         2         8        24
   15 #12321     |        1         0         1        15 |       12         3        11        27
   16 #12318     |        0         0         1        13 |        7         3        10        24
   17 #12319     |        0         0         1        13 |       11         3         9        25
   18 #12318     |        0         0         0        12 |        8         2         8        20
   19 #12319     |        0         0         1        18 |       10         2         9        28
   20 #12317     |        0         0         0        20 |        9         3         8        34
   21 #12318     |        0         0         0        13 |        8         3         8        28
   22 #12319     |        0         0         1        11 |        8         3        10        22
   23 #12320     |       28         0         1        28 |       41         3        11        41
  rtla timerlat hit stop tracing
  ## CPU 23 hit stop tracing, analyzing it ##
  IRQ handler delay:				      	    27.49 us (65.52 %)
  IRQ latency:						    28.13 us
  Timerlat IRQ duration:				     9.59 us (22.85 %)
  Blocking thread:					     3.79 us (9.03 %)
			objtool:49256    		     3.79 us
    Blocking thread stacktrace
		-> timerlat_irq
		-> __hrtimer_run_queues
		-> hrtimer_interrupt
		-> __sysvec_apic_timer_interrupt
		-> sysvec_apic_timer_interrupt
		-> asm_sysvec_apic_timer_interrupt
		-> _raw_spin_unlock_irqrestore
		-> cgroup_rstat_flush_locked
		-> cgroup_rstat_flush_irqsafe
		-> mem_cgroup_flush_stats
		-> mem_cgroup_wb_stats
		-> balance_dirty_pages
		-> balance_dirty_pages_ratelimited_flags
		-> btrfs_buffered_write
		-> btrfs_do_write_iter
		-> vfs_write
		-> __x64_sys_pwrite64
		-> do_syscall_64
		-> entry_SYSCALL_64_after_hwframe
  ------------------------------------------------------------------------
    Thread latency:					    41.96 us (100%)

  The system has exit from idle latency!
    Max timerlat IRQ latency from idle: 17.48 us in cpu 4
  Saving trace to timerlat_trace.txt
 ----------------------------------------- >% -----------------------------------------------------

In this case, the major factor was the delay suffered by the IRQ handler
that handles timerlat wakeup: 65.52 %. This can be caused by the
current thread masking interrupts, which can be seen in the blocking
thread stacktrace: the current thread (objtool:49256) disabled interrupts
via raw spin lock operations inside mem cgroup, while doing write
syscall in a btrfs file system.

A simple search for the function name on Google shows that this is
a legit case for disabling the interrupts:

  cgroup: Use irqsave in cgroup_rstat_flush_locked()
  lore.kernel.org/linux-mm/20220301122143.1521823-2-bigeasy@linutronix.de/

The output also prints other reasons for the latency root cause, such as:

  - an IRQ that happened before the IRQ handler that caused delays
  - The interference from NMI, IRQ, Softirq, and Threads

The details about how these factors affect the scheduling latency
can be found here:

   https://bristot.me/demystifying-the-real-time-linux-latency/

Link: https://lkml.kernel.org/r/3d45f40e630317f51ac6d678e2d96d310e495729.1675179318.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-02 10:48:04 -05:00
Daniel Bristot de Oliveira 27e348b221 rtla/timerlat: Add auto-analysis core
Currently, timerlat displays a summary of the timerlat tracer results
saving the trace if the system hits a stop condition.

While this represented a huge step forward, the root cause was not
that is accessible to non-expert users.

The auto-analysis fulfill this gap by parsing the trace timerlat runs,
printing an intuitive auto-analysis.

Link: https://lkml.kernel.org/r/1ee073822f6a2cbb33da0c817331d0d4045e837f.1675179318.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-02-02 10:48:03 -05:00
Andreas Ziegler 1fab1469b6 tools/tracing/rtla: osnoise_hist: display average with two-digit precision
Calculate average value in osnoise-hist summary with two-digit
precision to avoid displaying too optimitic results.

Link: https://lkml.kernel.org/r/20230103103400.275566-3-br015@umbiko.net

Signed-off-by: Andreas Ziegler <br015@umbiko.net>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-31 19:23:36 -05:00
Andreas Ziegler fe137a4fe0 tools/tracing/rtla: osnoise_hist: use total duration for average calculation
Sampled durations must be weighted by observed quantity, to arrive at a correct
average duration value.

Perform calculation of total duration by summing (duration * count).

Link: https://lkml.kernel.org/r/20230103103400.275566-2-br015@umbiko.net

Fixes: 829a6c0b56 ("rtla/osnoise: Add the hist mode")

Signed-off-by: Andreas Ziegler <br015@umbiko.net>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2023-01-31 19:23:36 -05:00
John Kacur 4c68743748 rtla: Fix exit status when returning from calls to usage()
rtla_usage(), osnoise_usage() and timerlat_usage() all exit with an
error status.

However when these are called from help, they should exit with a
non-error status.

Fix this by passing the exit status to the functions.

Note, although we remove the subsequent call to exit after calling
usage, we leave it in at the end of a function to suppress the compiler
warning "control reaches end of a non-void function".

Link: https://lkml.kernel.org/r/20221107144313.22470-1-jkacur@redhat.com

Signed-off-by: John Kacur <jkacur@redhat.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-12-09 18:06:24 -05:00
Steven Rostedt (Google) 20aec89aac rtla: Consolidate and show all necessary libraries that failed for building
When building rtla tools, if the necessary libraries are not installed
(libtraceevent and libtracefs), show the ones that are missing in one
consolidated output, and also show how to install them (at least for
Fedora).

Link: https://lore.kernel.org/all/CAHk-=wh+e1qcCnEYJ3JRDVLNCYbJ=0u+Ts5bOYZnY3mX_k-hFA@mail.gmail.com/
Link: https://lkml.kernel.org/r/20220810113918.5d19ce59@gandalf.local.home

Suggested-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-10 12:03:02 -04:00
Ben Hutchings 1a7b22ab15 tools/rtla: Build with EXTRA_{C,LD}FLAGS
To allow for distributions and other builders to apply hardening
policy and other customisation, append EXTRA_CFLAGS and EXTRA_LDFLAGS
to the corresponding variables.

Link: https://lore.kernel.org/linux-trace-devel/YtLBshz0nMQ7530H@decadent.org.uk

Signed-off-by: Ben Hutchings <benh@debian.org>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-10 11:46:28 -04:00
Ben Hutchings ff5a55dcdb tools/rtla: Fix command symlinks
"ln -s" stores the next argument directly as the symlink target, so
it needs to be a relative path.  In this case, just "rtla".

Link: https://lore.kernel.org/linux-trace-devel/YtLBXMI6Ui4HLIF1@decadent.org.uk

Fixes: 0605bf009f ("rtla: Add osnoise tool")
Fixes: a828cd18bc ("rtla: Add timerlat tool and timelart top mode")
Signed-off-by: Ben Hutchings <benh@debian.org>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-10 11:45:59 -04:00
Alexandre Vicenzi f1432cd24c rtla: Fix tracer name
The correct tracer name is timerlat and not timelat.

Link: https://lore.kernel.org/linux-trace-devel/20220808180343.22262-1-alexandre.vicenzi@suse.com

Signed-off-by: Alexandre Vicenzi <alexandre.vicenzi@suse.com>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-08-10 11:43:59 -04:00
Andreas Schwab dd0b15bda4 rtla: Define syscall numbers for riscv
RISC-V uses the same (generic) syscall numbers as ARM64.

Link: https://lkml.kernel.org/r/mvma68wl2ul.fsf@suse.de

Signed-off-by: Andreas Schwab <schwab@suse.de>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-31 17:04:05 -04:00
Andreas Schwab 4f753c3be5 rtla: Fix double free
Avoid double free by making trace_instance_destroy indempotent.  When
trace_instance_init fails, it calls trace_instance_destroy, but its only
caller osnoise_destroy_tool calls it again.

Link: https://lkml.kernel.org/r/mvmilnlkyzx.fsf_-_@suse.de

Fixes: 0605bf009f ("rtla: Add osnoise tool")
Signed-off-by: Andreas Schwab <schwab@suse.de>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-31 17:03:38 -04:00
Daniel Bristot de Oliveira c7d8a598c5 rtla: Fix Makefile when called from -C tools/
Sedat Dilek reported an error on rtla Makefile when running:

    $ make -C tools/ clean
    [...]
    make[2]: Entering directory
    '/home/dileks/src/linux-kernel/git/tools/tracing/rtla'
    [...]
    '/home/dileks/src/linux-kernel/git/Documentation/tools/rtla'
    /bin/sh: 1: test: rtla-make[2]:: unexpected operator    <------ The problem
    rm: cannot remove '/home/dileks/src/linux-kernel/git': Is a directory
    make[2]: *** [Makefile:120: clean] Error 1
    make[2]: Leaving directory

This occurred because the rtla calls kernel's Makefile to get the
version in silence mode, e.g.,

    $ make -sC ../../.. kernelversion
    5.19.0-rc4

But the -s is being ignored when rtla's makefile is called indirectly,
so the output looks like this:

    $ make -C ../../.. kernelversion
    make: Entering directory '/root/linux'
    5.19.0-rc4
    make: Leaving directory '/root/linux'

Using 'grep -v make' avoids this problem, e.g.,

    $ make -C ../../.. kernelversion | grep -v make
    5.19.0-rc4

Thus, add | grep -v make.

Link: https://lkml.kernel.org/r/870c02d4d97a921f02a31fa3b229fc549af61a20.1657747763.git.bristot@kernel.org

Fixes: 8619e32825 ("rtla: Follow kernel version")
Reported-by: Sedat Dilek <sedat.dilek@gmail.com>
Tested-by: Sedat Dilek <sedat.dilek@gmail.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-31 17:02:15 -04:00
jianchunfu b5f37a0b6f rtla/utils: Use calloc and check the potential memory allocation failure
Replace malloc with calloc and add memory allocating check
of mon_cpus before used.

Link: https://lkml.kernel.org/r/20220615073348.6891-1-jianchunfu@cmss.chinamobile.com

Fixes: 7d0dc9576d ("rtla/timerlat: Add --dma-latency option")
Signed-off-by: jianchunfu <jianchunfu@cmss.chinamobile.com>
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-07-11 21:14:29 -04:00
Daniel Bristot de Oliveira dada03db9b rtla: Remove procps-ng dependency
Daniel Wagner reported to me that readproc.h got deprecated. Also,
while the procps-ng library was available on Fedora, it was not available
on RHEL, which is a piece of evidence that it was not that used.

rtla uses procps-ng only to find the PID of the tracers' workload.

I used the procps-ng library to avoid reinventing the wheel. But in this
case, reinventing the wheel took me less time than the time we already
took trying to work around problems.

Implement a function that reads /proc/ entries, checking if:
	- the entry is a directory
	- the directory name is composed only of digits (PID)
	- the directory contains the comm file
	- the comm file contains a comm that matches the tracers'
	  workload prefix.
	- then return true; otherwise, return false.

And use it instead of procps-ng.

Link: https://lkml.kernel.org/r/e8276e122ee9eb2c5a0ba8e673fb6488b924b825.1652423574.git.bristot@kernel.org

Cc: John Kacur <jkacur@redhat.com>
Cc: Steven Rostedt <rostedt@goodmis.org>
Cc: Tao Zhou <tao.zhou@linux.dev>
Fixes: b1696371d8 ("rtla: Helper functions for rtla")
Reported-by: Daniel Wagner <dwagner@suse.de>
Reviewed-by: Daniel Wagner <dwagner@suse.de>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 15:20:46 -04:00
Daniel Bristot de Oliveira 941a53c39a rtla: Fix __set_sched_attr error message
rtla's function __set_sched_attr() was borrowed from stalld, but I
forgot to update the error message to something meaningful for rtla.

 Update the error message from:
        boost_with_deadline failed to boost pid PID: STRERROR
 to a proper one:
        Failed to set sched attributes to the pid PID: STRERROR

Link: https://lkml.kernel.org/r/a2d19b2c53f6512aefd1ee7f8c1bd19d4fc8b99d.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/eeded730413e7feaa13f946924bcf2cbf7dd9561.1650617571.git.bristot@kernel.org/

Fixes: b1696371d8 ("rtla: Helper functions for rtla")
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 15:18:29 -04:00
John Kacur 22d146f7c1 rtla: Minor grammar fix for rtla README
- Change to "The rtla meta-tool includes"
- Remove an unnecessary "But, "
- Adjust the formatting of the paragraph resulting from the changes.
- Simplify the wording for the libraries and tools.

Link: https://lkml.kernel.org/r/437f0accdde53713ab3cce46f3564be00487e031.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/20220408161012.10544-1-jkacur@redhat.com/

Cc: Daniel Bristot de Oliveria <bristot@kernel.org>
Fixes: 79ce8f43ac ("rtla: Real-Time Linux Analysis tool")
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 15:18:29 -04:00
John Kacur 39c3d84cb5 rtla: Don't overwrite existing directory mode
The mode on /usr/bin is often 555 these days,
but make install on rtla overwrites this with 755

Fix this by preserving the current directory if it exists.

Link: https://lkml.kernel.org/r/8c294a6961080a1970fd8b73f7bcf1e3984579e2.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/20220402043939.6962-1-jkacur@redhat.com

Cc: Daniel Bristot de Oliveria <bristot@redhat.com>
Fixes: 79ce8f43ac ("rtla: Real-Time Linux Analysis tool")
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: John Kacur <jkacur@redhat.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 15:18:28 -04:00
Wan Jiabing 2a6b52ed72 rtla: Avoid record NULL pointer dereference
Fix the following null/deref_null.cocci errors:
./tools/tracing/rtla/src/osnoise_hist.c:870:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/osnoise_top.c:650:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/timerlat_hist.c:905:31-36: ERROR: record is NULL but dereferenced.
./tools/tracing/rtla/src/timerlat_top.c:700:31-36: ERROR: record is NULL but dereferenced.

"record" is NULL before calling osnoise_init_trace_tool.
Add a tag "out_free" to avoid dereferring a NULL pointer.

Link: https://lkml.kernel.org/r/ae0e4500d383db0884eb2820286afe34ca303778.1651247710.git.bristot@kernel.org
Link: https://lore.kernel.org/r/20220408151406.34823-1-wanjiabing@vivo.com/

Cc: kael_w@yeah.net
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Fixes: 51d64c3a18 ("rtla: Add -e/--event support")
Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Wan Jiabing <wanjiabing@vivo.com>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 15:18:28 -04:00
Daniel Bristot de Oliveira fe4d0d5dde rtla/Makefile: Properly handle dependencies
Linus had a problem compiling RTLA, saying:

"[...] I wish the tracing tools would do a bit more package
checking and helpful error messages too, rather than just
fail with:

    fatal error: tracefs.h: No such file or directory"

Which is indeed not a helpful message. Update the Makefile, adding
proper checks for the dependencies, with useful information about
how to resolve possible problems.

For example, the previous error is now reported as:

    $ make
    ********************************************
    ** NOTICE: libtracefs version 1.3 or higher not found
    **
    ** Consider installing the latest libtracefs from your
    ** distribution, e.g., 'dnf install libtracefs' on Fedora,
    ** or from source:
    **
    **  https://git.kernel.org/pub/scm/libs/libtrace/libtracefs.git/
    **
    ********************************************

These messages are inspired by the ones used on trace-cmd, as suggested
by Stevel Rostedt.

Link: https://lore.kernel.org/r/CAHk-=whxmA86E=csNv76DuxX_wYsg8mW15oUs3XTabu2Yc80yw@mail.gmail.com/

Changes from V1:
 - Moved the rst2man check to the install phase (when it is used).
 - Removed the procps-ng lib check [1] as it is being removed.

[1] a0f9f8c1030c66305c9b921057c3d483064d5529.1651220820.git.bristot@kernel.org

Link: https://lkml.kernel.org/r/3f1fac776c37e4b67c876a94e5a0e45ed022ff3d.1651238057.git.bristot@kernel.org

Cc: Ingo Molnar <mingo@kernel.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Reported-by: Linus Torvalds <torvalds@linux-foundation.org>
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-05-26 15:17:48 -04:00
Linus Torvalds b8321ed4a4 Kbuild updates for v5.18
- Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
    additional flags to be passed to user-space programs.
 
  - Fix missing fflush() bugs in Kconfig and fixdep
 
  - Fix a minor bug in the comment format of the .config file
 
  - Make kallsyms ignore llvm's local labels, .L*
 
  - Fix UAPI compile-test for cross-compiling with Clang
 
  - Extend the LLVM= syntax to support LLVM=<suffix> form for using a
    particular version of LLVm, and LLVM=<prefix> form for using custom
    LLVM in a particular directory path.
 
  - Clean up Makefiles
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Merge tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild

Pull Kbuild updates from Masahiro Yamada:

 - Add new environment variables, USERCFLAGS and USERLDFLAGS to allow
   additional flags to be passed to user-space programs.

 - Fix missing fflush() bugs in Kconfig and fixdep

 - Fix a minor bug in the comment format of the .config file

 - Make kallsyms ignore llvm's local labels, .L*

 - Fix UAPI compile-test for cross-compiling with Clang

 - Extend the LLVM= syntax to support LLVM=<suffix> form for using a
   particular version of LLVm, and LLVM=<prefix> form for using custom
   LLVM in a particular directory path.

 - Clean up Makefiles

* tag 'kbuild-v5.18-v2' of git://git.kernel.org/pub/scm/linux/kernel/git/masahiroy/linux-kbuild:
  kbuild: Make $(LLVM) more flexible
  kbuild: add --target to correctly cross-compile UAPI headers with Clang
  fixdep: use fflush() and ferror() to ensure successful write to files
  arch: syscalls: simplify uapi/kapi directory creation
  usr/include: replace extra-y with always-y
  certs: simplify empty certs creation in certs/Makefile
  certs: include certs/signing_key.x509 unconditionally
  kallsyms: ignore all local labels prefixed by '.L'
  kconfig: fix missing '# end of' for empty menu
  kconfig: add fflush() before ferror() check
  kbuild: replace $(if A,A,B) with $(or A,B)
  kbuild: Add environment variables for userprogs flags
  kbuild: unify cmd_copy and cmd_shipped
2022-03-31 11:59:03 -07:00
Daniel Bristot de Oliveira 75016ca3ac rtla: Tools main loop cleanup
I probably started using "do {} while();", but changed all but osnoise_top
to "while(){};" leaving the ; behind.

Cleanup the main loop code, making all tools use "while() {}"

Changcheng Deng reported this problem, as reported by coccicheck:

Fix the following coccicheck review:
./tools/tracing/rtla/src/timerlat_hist.c: 800: 2-3: Unneeded semicolon
./tools/tracing/rtla/src/osnoise_hist.c:  776: 2-3: Unneeded semicolon
./tools/tracing/rtla/src/timerlat_top.c:  596: 2-3: Unneeded semicolon

Link: https://lkml.kernel.org/r/3c1642110aa87c396f5da4a037dabc72dbb9c601.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Reported-by: Changcheng Deng <deng.changcheng@zte.com.cn>
Reported-by: Zeal Robot <zealci@zte.com.cn>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:50 -04:00
Daniel Bristot de Oliveira 7d0dc9576d rtla/timerlat: Add --dma-latency option
Add the --dma-latency to set /dev/cpu_dma_latency to the
specified value, this aims to avoid having exit from idle
states latencies that could be influencing the analysis.

Link: https://lkml.kernel.org/r/72ddb0d913459f13217086dadafad88a7c46dd28.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:50 -04:00
Daniel Bristot de Oliveira 7d38c35167 rtla/osnoise: Fix osnoise hist stop tracing message
rtla osnoise hist is printing the following message when hitting stop
tracing:

  printf("rtla timelat hit stop tracing\n");

which is obviosly wrong.

s/timerlat/osnoise/ fixing the printf.

Link: https://lkml.kernel.org/r/2b8f090556fe37b81d183b74ce271421f131c77b.1646247211.git.bristot@kernel.org

Fixes: 829a6c0b56 ("rtla/osnoise: Add the hist mode")
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:50 -04:00
Daniel Bristot de Oliveira 28d2160cb1 rtla: Check for trace off also in the trace instance
With the addition of --trigger option, it is also possible to stop
the trace from the -t tracing instance using the traceoff trigger.

Make rtla tools to check if the trace is stopped also in the trace
instance, stopping the execution of the tool.

Link: https://lkml.kernel.org/r/59fc7c6f23dddd5c8b7ef1782cf3da51ea2ce0f5.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:50 -04:00
Daniel Bristot de Oliveira 761916fd02 rtla/trace: Save event histogram output to a file
The hist: trigger generates a histogram in the file sys/event/hist.
If the hist: trigger is used, automatically save the histogram output of
the event sys:event in the sys_event_hist.txt file.

Link: https://lkml.kernel.org/r/b5c906af31d4e022ffe87fb0848fac5c089087c8.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:50 -04:00
Daniel Bristot de Oliveira 44f3a37d1d rtla: Add --filter support
Add --filter option. This option enables a trace event filtering of the
previous -e sys:event argument.

This option is available for all current tools.

Link: https://lkml.kernel.org/r/509d70b6348d3e5bcbf1f07ab725ce08d063149a.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:50 -04:00
Daniel Bristot de Oliveira 5487b6ce26 rtla/trace: Add trace event filter helpers
Add a set of helper functions to allow rtla tools to filter events
in the trace instance.

Link: https://lkml.kernel.org/r/12623b1684684549d53b90f4bf66fae44584fd14.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:50 -04:00
Daniel Bristot de Oliveira 1a75489365 rtla: Add --trigger support
Add --trigger option. This option enables a trace event trigger to the
previous -e sys:event argument, allowing some advanced tracing options.

For instance, in a system with CPUs 2:23 isolated, it is possible to get
a stack trace of thread wakeup targeting those CPUs while running
osnoise with the following command line:

 # osnoise top -c 2-23 -a 50 -e sched:sched_wakeup --trigger="stacktrace if target_cpu >= 2"

This option is available for all current tools.

Link: https://lkml.kernel.org/r/07d2983d5f71261d4da89dbaf02efcad100ab8ee.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:49 -04:00
Daniel Bristot de Oliveira 336c92b26c rtla/trace: Add trace event trigger helpers
Add a set of helper functions to allow rtla tools to trigger event
actions in the trace instance.

Link: https://lkml.kernel.org/r/e0d31abe879a78a5600b64f904d0dfa8f76e4fbb.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:49 -04:00
Daniel Bristot de Oliveira 51d64c3a18 rtla: Add -e/--event support
Add -e/--event option. This option enables an event in the trace (-t)
session. The argument can be a specific event, e.g., -e sched:sched_switch,
or all events of a system group, e.g., -e sched. Multiple -e are allowed.
It is only active when -t or -a are set.

This option is available for all current tools.

Link: https://lkml.kernel.org/r/6a3b753be9b1e811953995f7f21a86918ad13390.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:49 -04:00
Daniel Bristot de Oliveira b5aa0be25c rtla/trace: Add trace events helpers
Add a set of helper functions to allow the rtla tools to enable
additional tracepoints in the trace instance.

Link: https://lkml.kernel.org/r/932398b36c1bbaa22c7810d7a40ca9b8c5595b94.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:49 -04:00
Daniel Bristot de Oliveira 173a3b0148 rtla/timerlat: Add the automatic trace option
Add the -a/--auto <arg in us> option. This option sets some commonly
used options while debugging the system. It aims to help users produce
reports in the field, reducing the number of arguments passed to the
tool in the first approach to a problem.

It is equivalent to setting osnoise/stop_tracing_total_us and print_stack
with the argument, and saving the trace to timerlat_trace.txt file if the
trace is stopped automatically.

Link: https://lkml.kernel.org/r/92438f7ef132c731f538cebdf77850300afe04a5.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:49 -04:00
Daniel Bristot de Oliveira 2b622edd5e rtla/osnoise: Add the automatic trace option
Add the -a/--auto <arg in us> option. This option sets some commonly
used options while debugging the system. It aims to help users produce
reports in the field, reducing the number of arguments passed to the
tool in the first approach to a problem.

It is equivalent to setting osnoise/stop_tracing_us with the argument,
setting tracing_thresh to 1 us, and saving the trace to osnoise_trace.txt
file if the trace is stopped automatically.

Link: https://lkml.kernel.org/r/ef04c961b227eb93a83cd0b54bfca45e1a381b77.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:49 -04:00
Daniel Bristot de Oliveira d635316ae9 rtla/osnoise: Add an option to set the threshold
Add the -T/--threshold option to set the minimum threshold to be
considered a noise to osnoise top and hist commands. Also update
the man pages.

Link: https://lkml.kernel.org/r/031861200ffdb24a1df4aa72c458706889a20d5d.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:49 -04:00
Daniel Bristot de Oliveira 61c57d578b rtla/osnoise: Add support to adjust the tracing_thresh
osnoise uses the tracing_thresh parameter to define the delta between
two reads of the time to be considered a noise.

Add support to get and set the tracing_thresh from osnoise tools.

Link: https://lkml.kernel.org/r/715ad2a53fd40e41bab8c3f1214c1a94e12fb595.1646247211.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: Clark Williams <williams@redhat.com>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-03-15 14:36:48 -04:00
Daniel Bristot de Oliveira 90f59ee41a rtla/osnoise: Fix error message when failing to enable trace instance
When a trace instance creation fails, tools are printing:

	Could not enable -> osnoiser <- tracer for tracing

Print the actual (and correct) name of the tracer it fails to enable.

Link: https://lkml.kernel.org/r/53ef0582605af91eca14b19dba9fc9febb95d4f9.1645206561.git.bristot@kernel.org

Fixes: b1696371d8 ("rtla: Helper functions for rtla")
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 21:05:30 -05:00
Daniel Bristot de Oliveira 316f710172 rtla/osnoise: Free params at the exit
The variable that stores the parsed command line arguments are not
being free()d at the rtla osnoise top exit path.

Free params variable before exiting.

Link: https://lkml.kernel.org/r/0be31d8259c7c53b98a39769d60cfeecd8421785.1645206561.git.bristot@kernel.org

Fixes: 1eceb2fc2c ("rtla/osnoise: Add osnoise top mode")
Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 21:05:30 -05:00
Daniel Bristot de Oliveira dd48f316a1 rtla/hist: Make -E the short version of --entries
Currently, --entries uses -e as the short version in the hist mode of
timerlat and osnoise tools. But as -e is already used to enable events
on trace sessions by other tools, thus let's keep it available for the
same usage for all rtla tools.

Make -E the short version of --entries for hist mode on all tools.

Note: rtla was merged in this merge window, so rtla was not released yet.

Link: https://lkml.kernel.org/r/5dbf0cbe7364d3a05e708926b41a097c59a02b1e.1645206561.git.bristot@kernel.org

Cc: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-25 21:05:30 -05:00
Masahiro Yamada 5c8166419a kbuild: replace $(if A,A,B) with $(or A,B)
$(or ...) is available since GNU Make 3.81, and useful to shorten the
code in some places.

Covert as follows:

  $(if A,A,B)  -->  $(or A,B)

This patch also converts:

  $(if A, A, B) --> $(or A, B)

Strictly speaking, the latter is not an equivalent conversion because
GNU Make keeps spaces after commas; if A is not empty, $(if A, A, B)
expands to " A", while $(or A, B) expands to "A".

Anyway, preceding spaces are not significant in the code hunks I touched.

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
Reviewed-by: Nicolas Schier <nicolas@fjasle.eu>
2022-02-15 12:25:56 +09:00
Daniel Bristot de Oliveira 4bbf59a9db rtla: Fix segmentation fault when failing to enable -t
rtla osnoise and timerlat are causing a segmentation fault when running
with the --trace option on a kernel that does not support multiple
instances. For example:

    [root@f34 rtla]# rtla osnoise top -t
    failed to enable the tracer osnoise
    Could not enable osnoiser tracer for tracing
    Failed to enable the trace instance
    Segmentation fault (core dumped)

This error happens because the exit code of the tools is trying
to destroy the trace instance that failed to be created.

Make osnoise_destroy_tool() aware of possible NULL osnoise_tool *,
and do not attempt to destroy it. This also simplifies the exit code.

Link: https://lkml.kernel.org/r/5660a2b6bf66c2655842360f2d7f6b48db5dba23.1644327249.git.bristot@kernel.org

Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Fixes: 1eceb2fc2c ("rtla/osnoise: Add osnoise top mode")
Fixes: 829a6c0b56 ("rtla/osnoise: Add the hist mode")
Fixes: a828cd18bc ("rtla: Add timerlat tool and timelart top mode")
Fixes: 1eeb6328e8 ("rtla/timerlat: Add timerlat hist mode")
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-08 11:23:09 -05:00
Daniel Bristot de Oliveira 1a6229096b rtla/trace: Error message fixup
Use capital and change "tracer %s" to "%s tracer".

No functional change.

Link: https://lkml.kernel.org/r/361697d27431afefa64c67c323564205385c418d.1643990447.git.bristot@kernel.org

Fixes: b1696371d8 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-04 12:39:28 -05:00
Daniel Bristot de Oliveira f35491b861 rtla/utils: Fix session duration parsing
Use gmtime to format the duration time. This avoids problems when the
system uses local time different of Pisa's Local Time.

Link: https://lkml.kernel.org/r/a2f0a37bc006c2561bb8ecd871cd70532b4a9f2d.1643990447.git.bristot@kernel.org

Fixes: b1696371d8 ("rtla: Helper functions for rtla")
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-04 12:39:28 -05:00
Daniel Bristot de Oliveira 8619e32825 rtla: Follow kernel version
To avoid having commits with new version, it is just easier to follow
kernel version.

Link: https://lkml.kernel.org/r/9c2df0d1de65cea96c7d731fe64781a2bb90c5b3.1643990447.git.bristot@kernel.org

Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-kernel@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-02-04 12:39:28 -05:00
Shuah Khan aa814c51ab tools/tracing: Update Makefile to build rtla
Update tracing Makefile to build/install/clean rtla tragets.

Link: https://lkml.kernel.org/r/20220126002234.79337-1-skhan@linuxfoundation.org

Reviewed-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-01-27 19:15:47 -05:00
Shuah Khan 2201aea114 rtla: Make doc build optional
rtla build fails due to doc build dependency on rst2man. Make
doc build optional so rtla could be built without docs. Leave
the install dependency on doc_install alone.

Link: https://lkml.kernel.org/r/20220126001301.79096-1-skhan@linuxfoundation.org

Acked-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Shuah Khan <skhan@linuxfoundation.org>
Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org>
2022-01-27 19:15:46 -05:00
Daniel Bristot de Oliveira d40d48e1f1 rtla: Add Documentation
Adds the basis for rtla documentation. This patch also
includes the rtla(1) man page.

As suggested by Jonathan Corbet, we are placing these man
pages at Documentation/tools/rtla, using rst format. It
is not linked to the official documentation, though.

The Makefile is based on bpftool's Documentation one.

Link: https://lkml.kernel.org/r/5f510f3e962fc0cd531c43f5a815544dd720c3f2.1639158831.git.bristot@kernel.org

Cc: Tao Zhou <tao.zhou@linux.dev>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Suggested-by: Steven Rostedt <rostedt@goodmis.org>
Suggested-by: Jonathan Corbet <corbet@lwn.net>
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-13 17:02:43 -05:00
Daniel Bristot de Oliveira 1eeb6328e8 rtla/timerlat: Add timerlat hist mode
The rtla hist hist mode displays a histogram of each tracer event
occurrence, both for IRQ and timer latencies. The tool also allows
many configurations of the timerlat tracer and the collection of
the tracer output.

Here is one example of the rtla timerlat hist mode output:
  ---------- %< ----------
 [root@alien ~]# rtla timerlat hist -c 0-3 -d 1M
 # RTLA timerlat histogram
 # Time unit is microseconds (us)
 # Duration:   0 00:01:00
 Index   IRQ-000   Thr-000   IRQ-001   Thr-001   IRQ-002   Thr-002   IRQ-003   Thr-003
 0         58572         0     59373         0     58691         0     58895         0
 1          1422     57021       628     57241      1310     56160      1102     56805
 2             6      2931         0      2695         0      3567         4      3031
 3             1        40         0        53         0       260         0       142
 4             0         7         0         5         0         6         0        17
 5             0         2         0         5         0         7         0         4
 6             0         0         0         2         0         1         0         1
 8             0         0         0         0         0         0         0         1
 over:         0         0         0         0         0         0         0         0
 count:    60001     60001     60001     60001     60001     60001     60001     60001
 min:          0         1         0         1         0         1         0         1
 avg:          0         1         0         1         0         1         0         1
 max:          3         5         1         6         1         6         2         8
  ---------- >% ----------

Running
 - rtla timerlat hist --help
provides information about the available options.

Link: https://lkml.kernel.org/r/7049ed3c46b7d6aceab18ffe7770003dfc4ddceb.1639158831.git.bristot@kernel.org

Cc: Tao Zhou <tao.zhou@linux.dev>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Tom Zanussi <zanussi@kernel.org>
Cc: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Clark Williams <williams@redhat.com>
Cc: John Kacur <jkacur@redhat.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Daniel Bristot de Oliveira <bristot@kernel.org>
Cc: linux-rt-users@vger.kernel.org
Cc: linux-trace-devel@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Signed-off-by: Daniel Bristot de Oliveira <bristot@kernel.org>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
2022-01-13 17:02:43 -05:00