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2023-12-12libperf cpumap: Replace usage of perf_cpu_map__new(NULL) with ↵Ian Rogers
perf_cpu_map__new_online_cpus() Passing NULL to perf_cpu_map__new() performs perf_cpu_map__new_online_cpus(), just directly call perf_cpu_map__new_online_cpus() to be more intention revealing. Reviewed-by: James Clark <james.clark@arm.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Ghiti <alexghiti@rivosinc.com> Cc: Andrew Jones <ajones@ventanamicro.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Atish Patra <atishp@rivosinc.com> Cc: Changbin Du <changbin.du@huawei.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Huacai Chen <chenhuacai@kernel.org> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: John Garry <john.g.garry@oracle.com> Cc: K Prateek Nayak <kprateek.nayak@amd.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Paolo Bonzini <pbonzini@redhat.com> Cc: Paran Lee <p4ranlee@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Sandipan Das <sandipan.das@amd.com> Cc: Sean Christopherson <seanjc@google.com> Cc: Steinar H. Gunderson <sesse@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Will Deacon <will@kernel.org> Cc: Yang Jihong <yangjihong1@huawei.com> Cc: Yang Li <yang.lee@linux.alibaba.com> Cc: Yanteng Si <siyanteng@loongson.cn> Cc: bpf@vger.kernel.org Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Link: https://lore.kernel.org/r/20231129060211.1890454-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2023-06-12perf bench epoll: Fix missing frees/puts on the exit pathIan Rogers
Issues detected by leak sanitizer. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: André Almeida <andrealmeid@igalia.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Ingo Molnar <mingo@redhat.com> Cc: Jiri Olsa <jolsa@kernel.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: https://lore.kernel.org/r/20230611233610.953456-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-10-04perf bench: Update use of pthread mutex/condIan Rogers
Switch to the use of mutex wrappers that provide better error checking. Signed-off-by: Ian Rogers <irogers@google.com> Reviewed-by: Adrian Hunter <adrian.hunter@intel.com> Acked-by: Namhyung Kim <namhyung@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexandre Truong <alexandre.truong@arm.com> Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andres Freund <andres@anarazel.de> Cc: Andrii Nakryiko <andrii@kernel.org> Cc: André Almeida <andrealmeid@igalia.com> Cc: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr> Cc: Colin Ian King <colin.king@intel.com> Cc: Dario Petrillo <dario.pk1@gmail.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Dave Marchevsky <davemarchevsky@fb.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Fangrui Song <maskray@google.com> Cc: Hewenliang <hewenliang4@huawei.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jason Wang <wangborong@cdjrlc.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kim Phillips <kim.phillips@amd.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Martin Liška <mliska@suse.cz> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Nathan Chancellor <nathan@kernel.org> Cc: Nick Desaulniers <ndesaulniers@google.com> Cc: Pavithra Gurushankar <gpavithrasha@gmail.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Quentin Monnet <quentin@isovalent.com> Cc: Ravi Bangoria <ravi.bangoria@amd.com> Cc: Remi Bernon <rbernon@codeweavers.com> Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: Song Liu <songliubraving@fb.com> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Tom Rix <trix@redhat.com> Cc: Weiguo Li <liwg06@foxmail.com> Cc: Wenyu Liu <liuwenyu7@huawei.com> Cc: William Cohen <wcohen@redhat.com> Cc: Zechuan Chen <chenzechuan1@huawei.com> Cc: bpf@vger.kernel.org Cc: llvm@lists.linux.dev Cc: yaowenbin <yaowenbin1@huawei.com> Link: https://lore.kernel.org/r/20220826164242.43412-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-04-09perf bench: Fix epoll bench to correct usage of affinity for machines with ↵Athira Rajeev
#CPUs > 1K The 'perf bench epoll' testcase fails on systems with more than 1K CPUs. Testcase: perf bench epoll all Result snippet: <<>> Run summary [PID 106497]: 1399 threads monitoring on 64 file-descriptors for 8 secs. perf: pthread_create: No such file or directory <<>> In epoll benchmarks (ctl, wait) pthread_create is invoked in do_threads from respective bench_epoll_* function. Though the logs shows direct failure from pthread_create, the actual failure is from "sched_setaffinity" returning EINVAL (invalid argument). This happens because the default mask size in glibc is 1024. To overcome this 1024 CPUs mask size limitation of cpu_set_t, change the mask size using the CPU_*_S macros. Patch addresses this by fixing all the epoll benchmarks to use CPU_ALLOC to allocate cpumask, CPU_ALLOC_SIZE for size, and CPU_SET_S to set the mask. Reported-by: Disha Goel <disgoel@linux.vnet.ibm.com> Signed-off-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com> Tested-by: Disha Goel <disgoel@linux.vnet.ibm.com> Acked-by: Ian Rogers <irogers@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Madhavan Srinivasan <maddy@linux.vnet.ibm.com> Cc: Michael Ellerman <mpe@ellerman.id.au> Cc: Nageswara R Sastry <rnsastry@linux.ibm.com> Cc: Srikar Dronamraju <srikar@linux.vnet.ibm.com> Cc: linuxppc-dev@lists.ozlabs.org Link: https://lore.kernel.org/r/20220406175113.87881-3-atrajeev@linux.vnet.ibm.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-22perf cpumap: Migrate to libperf cpumap apiIan Rogers
Switch from directly accessing the perf_cpu_map to using the appropriate libperf API when possible. Using the API simplifies the job of refactoring use of perf_cpu_map. Signed-off-by: Ian Rogers <irogers@google.com> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Bayduraev <alexey.v.bayduraev@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: André Almeida <andrealmeid@collabora.com> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Cc: Darren Hart <dvhart@infradead.org> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Dmitriy Vyukov <dvyukov@google.com> Cc: Eric Dumazet <edumazet@google.com> Cc: German Gomez <german.gomez@arm.com> Cc: James Clark <james.clark@arm.com> Cc: Jin Yao <yao.jin@linux.intel.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: John Garry <john.garry@huawei.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Madhavan Srinivasan <maddy@linux.ibm.com> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Masami Hiramatsu <mhiramat@kernel.org> Cc: Miaoqian Lin <linmq006@gmail.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: Shunsuke Nakamura <nakamura.shun@fujitsu.com> Cc: Song Liu <song@kernel.org> Cc: Stephane Eranian <eranian@google.com> Cc: Stephen Brennan <stephen.s.brennan@oracle.com> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Thomas Richter <tmricht@linux.ibm.com> Cc: Yury Norov <yury.norov@gmail.com> Link: http://lore.kernel.org/lkml/20220122045811.3402706-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2022-01-12perf cpumap: Give CPUs their own typeIan Rogers
A common problem is confusing CPU map indices with the CPU, by wrapping the CPU with a struct then this is avoided. This approach is similar to atomic_t. Committer notes: To make it build with BUILD_BPF_SKEL=1 these files needed the conversions to 'struct perf_cpu' usage: tools/perf/util/bpf_counter.c tools/perf/util/bpf_counter_cgroup.c tools/perf/util/bpf_ftrace.c Also perf_env__get_cpu() was removed back in "perf cpumap: Switch cpu_map__build_map to cpu function". Additionally these needed to be fixed for the ARM builds to complete: tools/perf/arch/arm/util/cs-etm.c tools/perf/arch/arm64/util/pmu.c Suggested-by: John Garry <john.garry@huawei.com> Signed-off-by: Ian Rogers <irogers@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Ingo Molnar <mingo@redhat.com> Cc: James Clark <james.clark@arm.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kajol Jain <kjain@linux.ibm.com> Cc: Kan Liang <kan.liang@linux.intel.com> Cc: Leo Yan <leo.yan@linaro.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Mathieu Poirier <mathieu.poirier@linaro.org> Cc: Mike Leach <mike.leach@linaro.org> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Paul Clarke <pc@us.ibm.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Riccardo Mancini <rickyman7@gmail.com> Cc: Stephane Eranian <eranian@google.com> Cc: Suzuki Poulouse <suzuki.poulose@arm.com> Cc: Vineet Singh <vineet.singh@intel.com> Cc: coresight@lists.linaro.org Cc: linux-arm-kernel@lists.infradead.org Cc: zhengjun.xing@intel.com Link: https://lore.kernel.org/r/20220105061351.120843-49-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-03-23perf tools: Fix various typos in commentsIngo Molnar
Fix ~124 single-word typos and a few spelling errors in the perf tooling code, accumulated over the years. Signed-off-by: Ingo Molnar <mingo@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: https://lore.kernel.org/r/20210321113734.GA248990@gmail.com Link: http://lore.kernel.org/lkml/20210323160915.GA61903@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2021-02-12perf env: Remove unneeded internal/cpumap inclusionsIan Rogers
Minor cleanup. 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/20210211183914.4093187-1-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-05-28tools feature: Rename HAVE_EVENTFD to HAVE_EVENTFD_SUPPORTArnaldo Carvalho de Melo
To be consistent with other such auto-detected features. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Anand K Mistry <amistry@google.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-22perf bench: Fix div-by-zero if runtime is zeroTommi Rantala
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>
2020-03-06perf bench: Clear struct sigaction before sigaction() syscallTommi Rantala
Avoid garbage in sigaction structs used in sigaction() syscalls. Valgrind is complaining about it. Signed-off-by: Tommi Rantala <tommi.t.rantala@nokia.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Changbin Du <changbin.du@intel.com> Cc: Darren Hart <dvhart@infradead.org> 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> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lore.kernel.org/lkml/20200305083714.9381-4-tommi.t.rantala@nokia.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-03-03perf bench: Share some global variables to fix build with gcc 10Arnaldo Carvalho de Melo
Noticed with gcc 10 (fedora rawhide) that those variables were not being declared as static, so end up with: ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here ld: /tmp/build/perf/bench/epoll-wait.o:/git/perf/tools/perf/bench/epoll-wait.c:93: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `end'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `start'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here ld: /tmp/build/perf/bench/epoll-ctl.o:/git/perf/tools/perf/bench/epoll-ctl.c:38: multiple definition of `runtime'; /tmp/build/perf/bench/futex-hash.o:/git/perf/tools/perf/bench/futex-hash.c:40: first defined here make[4]: *** [/git/perf/tools/build/Makefile.build:145: /tmp/build/perf/bench/perf-in.o] Error 1 Prefix those with bench__ and add them to bench/bench.h, so that we can share those on the tools needing to access those variables from signal handlers. Acked-by: Thomas Gleixner <tglx@linutronix.de> Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Davidlohr Bueso <dave@stgolabs.net> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: http://lore.kernel.org/lkml/20200303155811.GD13702@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-09-20perf env: Remove needless cpumap.h headerArnaldo Carvalho de Melo
Only a 'struct perf_cmp_map' forward allocation is necessary, fix the places that need the header but were getting it indirectly, by luck, from env.h. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lkml.kernel.org/n/tip-3sj3n534zghxhk7ygzeaqlx9@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-08-29perf tools: Move everything related to sys_perf_event_open() to perf-sys.hArnaldo Carvalho de Melo
And remove unneeded include directives from perf-sys.h to prune the header dependency tree. Fixup the fallout in places where definitions were being used without the needed include directives that were being satisfied because they were in perf-sys.h. Cc: Adrian Hunter <adrian.hunter@intel.com> Cc: Jiri Olsa <jolsa@kernel.org> Cc: Namhyung Kim <namhyung@kernel.org> Link: https://lkml.kernel.org/n/tip-7b1zvugiwak4ibfa3j6ott7f@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29libperf: Add perf_cpu_map__new()/perf_cpu_map__read() functionsJiri Olsa
Moving the following functions from tools/perf: cpu_map__new() cpu_map__read() to libperf with the following names: perf_cpu_map__new() perf_cpu_map__read() Committer notes: Fixed up this one: tools/perf/arch/arm/util/cs-etm.c Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20190721112506.12306-44-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-07-29perf cpu_map: Rename struct cpu_map to struct perf_cpu_mapJiri Olsa
Rename struct cpu_map to struct perf_cpu_map, so it could be part of libperf. Committer notes: Added fixes for arm64, provided by Jiri. Signed-off-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Michael Petlan <mpetlan@redhat.com> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Link: http://lkml.kernel.org/r/20190721112506.12306-3-jolsa@kernel.org Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-03-19perf tools: Fix errors under optimization level '-Og'Changbin Du
Optimization level '-Og' offers a reasonable level of optimization while maintaining fast compilation and a good debugging experience. This patch tries to make it work. $ make DEBUG=1 EXTRA_CFLAGS='-Og' bench/epoll-ctl.c: In function ‘do_threads’: bench/epoll-ctl.c:274:9: error: ‘ret’ may be used uninitialized in this function [-Werror=maybe-uninitialized] return ret; ^~~ ... Signed-off-by: Changbin Du <changbin.du@gmail.com> Reviewed-by: Jiri Olsa <jolsa@kernel.org> Cc: Alexei Starovoitov <ast@kernel.org> Cc: Daniel Borkmann <daniel@iogearbox.net> Cc: Namhyung Kim <namhyung@kernel.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Steven Rostedt (VMware) <rostedt@goodmis.org> Link: http://lkml.kernel.org/r/20190316080556.3075-4-changbin.du@gmail.com Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2018-11-21perf bench: Add epoll parallel epoll_wait benchmarkDavidlohr Bueso
This program benchmarks concurrent epoll_wait(2) for file descriptors that are monitored with with EPOLLIN along various semantics, by a single epoll instance. Such conditions can be found when using single/combined or multiple queuing when load balancing. Each thread has a number of private, nonblocking file descriptors, referred to as fdmap. A writer thread will constantly be writing to the fdmaps of all threads, minimizing each threads's chances of epoll_wait not finding any ready read events and blocking as this is not what we want to stress. Full details in the start of the C file. Committer testing: # perf bench Usage: perf bench [<common options>] <collection> <benchmark> [<options>] # List of all available benchmark collections: sched: Scheduler and IPC benchmarks mem: Memory access benchmarks numa: NUMA scheduling and MM benchmarks futex: Futex stressing benchmarks epoll: Epoll stressing benchmarks all: All benchmarks # perf bench epoll # List of available benchmarks for collection 'epoll': wait: Benchmark epoll concurrent epoll_waits all: Run all futex benchmarks # perf bench epoll wait # Running 'epoll/wait' benchmark: Run summary [PID 19295]: 3 threads monitoring on 64 file-descriptors for 8 secs. [thread 0] fdmap: 0xdaa650 ... 0xdaa74c [ 328241 ops/sec ] [thread 1] fdmap: 0xdaa900 ... 0xdaa9fc [ 351695 ops/sec ] [thread 2] fdmap: 0xdaabb0 ... 0xdaacac [ 381423 ops/sec ] Averaged 353786 operations/sec (+- 4.35%), total secs = 8 # Committer notes: Fix the build on debian:experimental-x-mips, debian:experimental-x-mipsel and others: CC /tmp/build/perf/bench/epoll-wait.o bench/epoll-wait.c: In function 'writerfn': bench/epoll-wait.c:399:12: error: format '%ld' expects argument of type 'long int', but argument 2 has type 'size_t' {aka 'unsigned int'} [-Werror=format=] printinfo("exiting writer-thread (total full-loops: %ld)\n", iter); ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~ bench/epoll-wait.c:86:31: note: in definition of macro 'printinfo' do { if (__verbose) { printf(fmt, ## arg); fflush(stdout); } } while (0) ^~~ cc1: all warnings being treated as errors Signed-off-by: Davidlohr Bueso <dbueso@suse.de> Tested-by: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Davidlohr Bueso <dbueso@suse.de> Cc: Jason Baron <jbaron@akamai.com> <jbaron@akamai.com> Link: http://lkml.kernel.org/r/20181106152226.20883-2-dave@stgolabs.net Link: http://lkml.kernel.org/r/20181106182349.thdkpvshkna5vd7o@linux-r8p5> [ Applied above fixup as per Davidlohr's request ] [ Use inttypes.h to print rlim_t fields, fixing the build on Alpine Linux / musl libc ] [ Check if eventfd() is available, i.e. if HAVE_EVENTFD is defined ] Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>