Commit Graph

12 Commits

Author SHA1 Message Date
Arnaldo Carvalho de Melo b0ad8ea664 perf tools: Remove unused 'prefix' from builtin functions
We got it from the git sources but never used it for anything, with the
place where this would be somehow used remaining:

  static int run_builtin(struct cmd_struct *p, int argc, const char **argv)
  {
	prefix = NULL;
	if (p->option & RUN_SETUP)
		prefix = NULL; /* setup_perf_directory(); */

Ditch it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-uw5swz05vol0qpr32c5lpvus@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-27 11:58:09 -03:00
Arnaldo Carvalho de Melo a0f213e14b perf bench futex: Fix build on musl + clang
When building with clang on a musl libc system, Alpine Linux, we end up
hitting a problem where memset() is used but its prototype is not
present, add it to avoid this:

  bench/futex-wake.c:99:3: error: implicitly declaring library function 'memset' with type 'void *(void *, int, unsigned long)'
        [-Werror,-Wimplicit-function-declaration]
                  CPU_ZERO(&cpu);
                  ^
  /usr/include/sched.h:127:23: note: expanded from macro 'CPU_ZERO'
  #define CPU_ZERO(set) CPU_ZERO_S(sizeof(cpu_set_t),set)
                        ^
  /usr/include/sched.h:110:30: note: expanded from macro 'CPU_ZERO_S'
  #define CPU_ZERO_S(size,set) memset(set,0,size)
                               ^
  bench/futex-wake.c:99:3: note: include the header <string.h> or explicitly provide a declaration for 'memset'

Found while updating my test build containers to build perf with clang in more
systems.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-jh10vaz2r98zl6gm5iau8prr@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-03-03 19:07:19 -03:00
Arnaldo Carvalho de Melo 16cab3226f Revert "perf bench futex: Sanitize numeric parameters"
This reverts commit 60758d6668.

Now that libsubcmd makes sure that OPT_UINTEGER options will not
return negative values, we can revert this patch while addressing
the problem it solved:

  # perf bench futex hash -t  -4
  # Running 'futex/hash' benchmark:
   Error: switch `t' expects an unsigned numerical value
   Usage: perf bench futex hash <options>

      -t, --threads <n>     Specify amount of threads
  # perf bench futex hash -t-4
  # Running 'futex/hash' benchmark:
   Error: switch `t' expects an unsigned numerical value
   Usage: perf bench futex hash <options>

      -t, --threads <n>     Specify amount of threads
  #

IMO it is more reasonable to flat out refuse to process a negative
number than to silently turn it into an absolute value.

This also helps in silencing clang's complaint about asking for an
absolute value of an unsigned integer:

  bench/futex-hash.c:133:10: error: taking the absolute value of unsigned type 'unsigned int' has no effect [-Werror,-Wabsolute-value]
          nsecs = futexbench_sanitize_numeric(nsecs);
                ^
  bench/futex.h:104:42: note: expanded from macro 'futexbench_sanitize_numeric'
  #define futexbench_sanitize_numeric(__n) abs((__n))
                                           ^
  bench/futex-hash.c:133:10: note: remove the call to 'abs' since unsigned values cannot be negative

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-2kl68v22or31vw643m2exz8x@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2017-02-14 15:19:17 -03:00
Davidlohr Bueso 60758d6668 perf bench futex: Sanitize numeric parameters
This gets rid of oddities such as:

  perf bench futex hash -t -4
  perf: calloc: Cannot allocate memory

Runtime (and many more) are equally busted, i.e. run for bogus amounts of
time. Just use the abs, instead of, for example errorring out.

Committer note:

After the patch:

  $ perf bench futex hash -t -4
  # Running 'futex/hash' benchmark:
  Run summary [PID 10178]: 4 threads, each operating on 1024 [private] futexes for 10 secs.

  [thread  0] futexes: 0x34f9fa0 ... 0x34faf9c [ 4702208 ops/sec ]
  [thread  1] futexes: 0x34fb140 ... 0x34fc13c [ 4707020 ops/sec ]
  [thread  2] futexes: 0x34fc2e0 ... 0x34fd2dc [ 4711526 ops/sec ]
  [thread  3] futexes: 0x34fd480 ... 0x34fe47c [ 4709683 ops/sec ]

  Averaged 4707609 operations/sec (+- 0.04%), total secs = 10
  $

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Link: http://lkml.kernel.org/r/1477342613-9938-3-git-send-email-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-25 09:50:53 -03:00
Davidlohr Bueso e2e1680fda perf bench futex: Avoid worker cacheline bouncing
Sebastian noted that overhead for worker thread ops (throughput)
accounting was producing 'perf' to appear in the profiles, consuming a
non-trivial (i.e. 13%) amount of CPU.

This is due to cacheline bouncing due to the increment of w->ops.

We can easily fix this by just working on a local copy and updating the
actual worker once done running, and ready to show the program summary.
There is no danger of the worker being concurrent, so we can trust that
no stale value is being seen by another thread.

This also gets rid of the unnecessary cache alignment hack; its not
worth it.

Reported-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Acked-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/1477342613-9938-2-git-send-email-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-25 09:50:47 -03:00
Sebastian Andrzej Siewior 34b753007d perf bench futex: Cache align the worker struct
It popped up in perf testing that the worker consumes some amount of
CPU. It boils down to the increment of `ops` which causes cache line
bouncing between the individual threads.

This patch aligns the struct by 256 bytes to ensure that not a cache
line is shared among CPUs. 128 byte is the x86 worst case and grep says
that L1_CACHE_SHIFT is set to 8 on s390.

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/20161016190803.3392-1-bigeasy@linutronix.de
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-10-24 11:07:45 -03:00
Arnaldo Carvalho de Melo 86695f59c9 perf bench futex: Add missing compiler.h header
Since these files use __maybe_unused, and that is defined in
linux/compiler.h, include it.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-1llbf59ut6xon6ti88jm0n9j@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-12 15:20:30 -03:00
Arnaldo Carvalho de Melo 9c304f6c71 perf bench: Disentangle headers
We should try avoiding that perf.h header, it includes way too much
stuff, making it difficult to use things like setting _GNU_SOURCE only
on a small set of headers.

Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-lb6eg9w1kzrwhv0gm3ho0h54@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-12 15:19:54 -03:00
Arnaldo Carvalho de Melo 8a15858904 perf bench: Add missing pthread.h include for CPU_*() macros
Cc: David Ahern <dsahern@gmail.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Hitoshi Mitake <mitake@dcl.info.waseda.ac.jp>
Cc: Jiri Olsa <jolsa@kernel.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Wang Nan <wangnan0@huawei.com>
Link: http://lkml.kernel.org/n/tip-48qbfv7tqs8n8ey74lbyfjtq@git.kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2016-07-12 15:19:52 -03:00
Josh Poimboeuf 4b6ab94eab perf subcmd: Create subcmd library
Move the subcommand-related files from perf to a new library named
libsubcmd.a.

Since we're moving files anyway, go ahead and rename 'exec_cmd.*' to
'exec-cmd.*' to be consistent with the naming of all the other files.

Signed-off-by: Josh Poimboeuf <jpoimboe@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/c0a838d4c878ab17fee50998811612b2281355c1.1450193761.git.jpoimboe@redhat.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2015-12-17 14:27:14 -03:00
Davidlohr Bueso 86c87e13f8 perf bench futex: Support operations for shared futexes
Unlike futex-hash, requeuing and wakeup benchmarks do not support shared
futexes, limiting the usefulness of the programs. Correct this, and
allow using the local -S parameter. The default remains using private
futexes.

Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Cc: Davidlohr Bueso <dbueso@suse.de>
Link: http://lkml.kernel.org/r/1412008868-22328-1-git-send-email-dave@stgolabs.net
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-09-29 15:43:21 -03:00
Davidlohr Bueso a043971141 perf bench: Add futex-hash microbenchmark
Introduce futexes to perf-bench and add a program that stresses and
measures the kernel's implementation of the hash table.

This is a multi-threaded program that simply measures the amount of
failed futex wait calls - we only want to deal with the hashing
overhead, so a negative return of futex_wait_setup() is enough to do the
trick.

An example run:

  $ perf bench futex hash -t 32
  Run summary [PID 10989]: 32 threads, each operating on 1024 [private] futexes for 10 secs.

  [thread  0] futexes: 0x19d9b10 ... 0x19dab0c [ 418713 ops/sec ]
  [thread  1] futexes: 0x19daca0 ... 0x19dbc9c [ 469913 ops/sec ]
  [thread  2] futexes: 0x19dbe30 ... 0x19dce2c [ 479744 ops/sec ]
  ...
  [thread 31] futexes: 0x19fbb80 ... 0x19fcb7c [ 464179 ops/sec ]

  Averaged 454310 operations/sec (+- 0.84%), total secs = 10

Signed-off-by: Davidlohr Bueso <davidlohr@hp.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
Cc: Aswin Chandramouleeswaran <aswin@hp.com>
Cc: Darren Hart <dvhart@linux.intel.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Low <jason.low2@hp.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Scott J Norton <scott.norton@hp.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Waiman Long <Waiman.Long@hp.com>
Link: http://lkml.kernel.org/r/1387081917-9102-2-git-send-email-davidlohr@hp.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2014-03-14 11:20:43 -03:00