perf bench inject-buildid: Use zfree() to reduce chances of use after free

Do defensive programming by using zfree() to initialize freed pointers
to NULL, so that eventual use after free result in a NULL pointer deref
instead of more subtle behaviour.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Move 'struct perf_sample' to a separate header file to disentangle headers

Some places were including event.h just to get 'struct perf_sample',
move it to a separate place so that we speed up a bit the build.

Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bench inject-buildid: Handle writen() errors

The build on fedora:35 and fedora:rawhide with clang is failing with:

49 41.00 fedora:35 : FAIL clang version 13.0.0 (Fedora 13.0.0~rc1-1.fc35)
bench/inject-buildid.c:351:6: error: variable 'len' set but not used [-Werror,-Wunused-but-set-variable]
u64 len = 0;
^
1 error generated.
make[3]: *** [/git/perf-5.14.0-rc7/tools/build/Makefile.build:139: bench] Error 2
50 41.11 fedora:rawhide : FAIL clang version 13.0.0 (Fedora 13.0.0~rc1-1.fc35)
bench/inject-buildid.c:351:6: error: variable 'len' set but not used [-Werror,-Wunused-but-set-variable]
u64 len = 0;
^
1 error generated.
make[3]: *** [/git/perf-5.14.0-rc7/tools/build/Makefile.build:139: bench] Error 2

That 'len' variable is not used at all, so just make sure all the
synthesize_RECORD() routines return ssize_t to propagate the writen()
return, as it may fail, ditch the 'ret' var and bail out if those
routines fail.

Fixes: 0bf02a0d80427f26 ("perf bench: Add build-id injection benchmark")
Acked-by: Namhyung Kim <namhyung@kernel.org>
Link: http://lore.kernel.org/lkml/CAM9d7cgEZNSor+B+7Y2C+QYGme_v5aH0Zn0RLfxoQ+Fy83EHrg@mail.gmail.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bench: Fix misspellings using codespell

$ codespell ./tool/perf/bench
tools/perf/bench/inject-buildid.c:375: tihs ==> this

Fix a typo found by codespell.

Signed-off-by: Xiong Zhenwu <xiong.zhenwu@zte.com.cn>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Ian Rogers <irogers@google.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/20210305092212.204923-1-xiong.zhenwu@zte.com.cn
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Pass build_id object to filename__read_build_id()

Pass a build_id object to filename__read_build_id function, so it can
populate the size of the build_id object.

Changing filename__read_build_id() code for both ELF/non-ELF code.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-3-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf tools: Use build_id object in dso

Replace build_id byte array with struct build_id object and all the code
that references it.

The objective is to carry size together with build id array, so it's
better to keep both together.

This is preparatory change for following patches, and there's no
functional change.

Signed-off-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lore.kernel.org/r/20201013192441.1299447-2-jolsa@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bench: Run inject-build-id with --buildid-all option too

For comparison, it now runs the benchmark twice - one if regular -b and
another for --buildid-all.

$ perf bench internals inject-build-id
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 21.002 msec (+- 0.172 msec)
Average time per event: 2.059 usec (+- 0.017 usec)
Average memory usage: 8169 KB (+- 0 KB)
Average build-id-all injection took: 19.543 msec (+- 0.124 msec)
Average time per event: 1.916 usec (+- 0.012 usec)
Average memory usage: 7348 KB (+- 0 KB)

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Acked-by: Ian Rogers <irogers@google.com>
Acked-by: Jiri Olsa <jolsa@redhat.com>
Link: https://lore.kernel.org/r/20201012070214.2074921-7-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>

perf bench: Add build-id injection benchmark

Sometimes I can see that 'perf record' piped with 'perf inject' take a
long time processing build-ids.

So introduce a inject-build-id benchmark to the internals benchmark
suite to measure its overhead regularly.

It runs the 'perf inject' command internally and feeds the given number
of synthesized events (MMAP2 + SAMPLE basically).

Usage: perf bench internals inject-build-id <options>

-i, --iterations <n> Number of iterations used to compute average (default: 100)
-m, --nr-mmaps <n> Number of mmap events for each iteration (default: 100)
-n, --nr-samples <n> Number of sample events per mmap event (default: 100)
-v, --verbose be more verbose (show iteration count, DSO name, etc)

By default, it measures average processing time of 100 MMAP2 events
and 10000 SAMPLE events. Below is a result on my laptop.

$ perf bench internals inject-build-id
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 25.789 msec (+- 0.202 msec)
Average time per event: 2.528 usec (+- 0.020 usec)
Average memory usage: 8411 KB (+- 7 KB)

Committer testing:

$ perf bench
Usage:
perf bench [<common options>] <collection> <benchmark> [<options>]

# List of all available benchmark collections:

sched: Scheduler and IPC benchmarks
syscall: System call benchmarks
mem: Memory access benchmarks
numa: NUMA scheduling and MM benchmarks
futex: Futex stressing benchmarks
epoll: Epoll stressing benchmarks
internals: Perf-internals benchmarks
all: All benchmarks

$ perf bench internals

# List of available benchmarks for collection 'internals':

synthesize: Benchmark perf event synthesis
kallsyms-parse: Benchmark kallsyms parsing
inject-build-id: Benchmark build-id injection

$ perf bench internals inject-build-id
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 14.202 msec (+- 0.059 msec)
Average time per event: 1.392 usec (+- 0.006 usec)
Average memory usage: 12650 KB (+- 10 KB)
Average build-id-all injection took: 12.831 msec (+- 0.071 msec)
Average time per event: 1.258 usec (+- 0.007 usec)
Average memory usage: 11895 KB (+- 10 KB)
$

$ perf stat -r5 perf bench internals inject-build-id
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 14.380 msec (+- 0.056 msec)
Average time per event: 1.410 usec (+- 0.006 usec)
Average memory usage: 12608 KB (+- 11 KB)
Average build-id-all injection took: 11.889 msec (+- 0.064 msec)
Average time per event: 1.166 usec (+- 0.006 usec)
Average memory usage: 11838 KB (+- 10 KB)
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 14.246 msec (+- 0.065 msec)
Average time per event: 1.397 usec (+- 0.006 usec)
Average memory usage: 12744 KB (+- 10 KB)
Average build-id-all injection took: 12.019 msec (+- 0.066 msec)
Average time per event: 1.178 usec (+- 0.006 usec)
Average memory usage: 11963 KB (+- 10 KB)
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 14.321 msec (+- 0.067 msec)
Average time per event: 1.404 usec (+- 0.007 usec)
Average memory usage: 12690 KB (+- 10 KB)
Average build-id-all injection took: 11.909 msec (+- 0.041 msec)
Average time per event: 1.168 usec (+- 0.004 usec)
Average memory usage: 11938 KB (+- 10 KB)
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 14.287 msec (+- 0.059 msec)
Average time per event: 1.401 usec (+- 0.006 usec)
Average memory usage: 12864 KB (+- 10 KB)
Average build-id-all injection took: 11.862 msec (+- 0.058 msec)
Average time per event: 1.163 usec (+- 0.006 usec)
Average memory usage: 12103 KB (+- 10 KB)
# Running 'internals/inject-build-id' benchmark:
Average build-id injection took: 14.402 msec (+- 0.053 msec)
Average time per event: 1.412 usec (+- 0.005 usec)
Average memory usage: 12876 KB (+- 10 KB)
Average build-id-all injection took: 11.826 msec (+- 0.061 msec)
Average time per event: 1.159 usec (+- 0.006 usec)
Average memory usage: 12111 KB (+- 10 KB)

Performance counter stats for 'perf bench internals inject-build-id' (5 runs):

4,267.48 msec task-clock:u # 1.502 CPUs utilized ( +- 0.14% )
0 context-switches:u # 0.000 K/sec
0 cpu-migrations:u # 0.000 K/sec
102,092 page-faults:u # 0.024 M/sec ( +- 0.08% )
3,894,589,578 cycles:u # 0.913 GHz ( +- 0.19% ) (83.49%)
140,078,421 stalled-cycles-frontend:u # 3.60% frontend cycles idle ( +- 0.77% ) (83.34%)
948,581,189 stalled-cycles-backend:u # 24.36% backend cycles idle ( +- 0.46% ) (83.25%)
5,835,587,719 instructions:u # 1.50 insn per cycle
# 0.16 stalled cycles per insn ( +- 0.21% ) (83.24%)
1,267,423,636 branches:u # 296.996 M/sec ( +- 0.22% ) (83.12%)
17,484,290 branch-misses:u # 1.38% of all branches ( +- 0.12% ) (83.55%)

2.84176 +- 0.00222 seconds time elapsed ( +- 0.08% )

$

Acked-by: Jiri Olsa <jolsa@redhat.com>
Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Link: https://lore.kernel.org/r/20201012070214.2074921-2-namhyung@kernel.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>