/* * * sched-pipe.c * * pipe: Benchmark for pipe() * * Based on pipe-test-1m.c by Ingo Molnar * http://people.redhat.com/mingo/cfs-scheduler/tools/pipe-test-1m.c * Ported to perf by Hitoshi Mitake */ #include "../perf.h" #include "../util/util.h" #include #include "../builtin.h" #include "bench.h" #include #include #include #include #include #include #include #include #include #include #include #include #include struct thread_data { int nr; int pipe_read; int pipe_write; pthread_t pthread; }; #define LOOPS_DEFAULT 1000000 static int loops = LOOPS_DEFAULT; /* Use processes by default: */ static bool threaded; static const struct option options[] = { OPT_INTEGER('l', "loop", &loops, "Specify number of loops"), OPT_BOOLEAN('T', "threaded", &threaded, "Specify threads/process based task setup"), OPT_END() }; static const char * const bench_sched_pipe_usage[] = { "perf bench sched pipe ", NULL }; static void *worker_thread(void *__tdata) { struct thread_data *td = __tdata; int m = 0, i; int ret; for (i = 0; i < loops; i++) { if (!td->nr) { ret = read(td->pipe_read, &m, sizeof(int)); BUG_ON(ret != sizeof(int)); ret = write(td->pipe_write, &m, sizeof(int)); BUG_ON(ret != sizeof(int)); } else { ret = write(td->pipe_write, &m, sizeof(int)); BUG_ON(ret != sizeof(int)); ret = read(td->pipe_read, &m, sizeof(int)); BUG_ON(ret != sizeof(int)); } } return NULL; } int bench_sched_pipe(int argc, const char **argv, const char *prefix __maybe_unused) { struct thread_data threads[2], *td; int pipe_1[2], pipe_2[2]; struct timeval start, stop, diff; unsigned long long result_usec = 0; int nr_threads = 2; int t; /* * why does "ret" exist? * discarding returned value of read(), write() * causes error in building environment for perf */ int __maybe_unused ret, wait_stat; pid_t pid, retpid __maybe_unused; argc = parse_options(argc, argv, options, bench_sched_pipe_usage, 0); BUG_ON(pipe(pipe_1)); BUG_ON(pipe(pipe_2)); gettimeofday(&start, NULL); for (t = 0; t < nr_threads; t++) { td = threads + t; td->nr = t; if (t == 0) { td->pipe_read = pipe_1[0]; td->pipe_write = pipe_2[1]; } else { td->pipe_write = pipe_1[1]; td->pipe_read = pipe_2[0]; } } if (threaded) { for (t = 0; t < nr_threads; t++) { td = threads + t; ret = pthread_create(&td->pthread, NULL, worker_thread, td); BUG_ON(ret); } for (t = 0; t < nr_threads; t++) { td = threads + t; ret = pthread_join(td->pthread, NULL); BUG_ON(ret); } } else { pid = fork(); assert(pid >= 0); if (!pid) { worker_thread(threads + 0); exit(0); } else { worker_thread(threads + 1); } retpid = waitpid(pid, &wait_stat, 0); assert((retpid == pid) && WIFEXITED(wait_stat)); } gettimeofday(&stop, NULL); timersub(&stop, &start, &diff); switch (bench_format) { case BENCH_FORMAT_DEFAULT: printf("# Executed %d pipe operations between two %s\n\n", loops, threaded ? "threads" : "processes"); result_usec = diff.tv_sec * USEC_PER_SEC; result_usec += diff.tv_usec; printf(" %14s: %lu.%03lu [sec]\n\n", "Total time", diff.tv_sec, (unsigned long) (diff.tv_usec / USEC_PER_MSEC)); printf(" %14lf usecs/op\n", (double)result_usec / (double)loops); printf(" %14d ops/sec\n", (int)((double)loops / ((double)result_usec / (double)USEC_PER_SEC))); break; case BENCH_FORMAT_SIMPLE: printf("%lu.%03lu\n", diff.tv_sec, (unsigned long) (diff.tv_usec / USEC_PER_MSEC)); break; default: /* reaching here is something disaster */ fprintf(stderr, "Unknown format:%d\n", bench_format); exit(1); break; } return 0; } >7space:mode:
authorThomas Gleixner <tglx@linutronix.de>2017-01-31 23:58:38 +0100
committerIngo Molnar <mingo@kernel.org>2017-02-01 08:37:27 +0100
commitdd86e373e09fb16b83e8adf5c48c421a4ca76468 (patch)
tree55703c2ea8584e303e342090614e0aab3509ab21 /net/sctp/primitive.c
parent0b3589be9b98994ce3d5aeca52445d1f5627c4ba (diff)
perf/x86/intel/rapl: Make package handling more robust
The package management code in RAPL relies on package mapping being available before a CPU is started. This changed with: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") because the ACPI/BIOS information turned out to be unreliable, but that left RAPL in broken state. This was not noticed because on a regular boot all CPUs are online before RAPL is initialized. A possible fix would be to reintroduce the mess which allocates a package data structure in CPU prepare and when it turns out to already exist in starting throw it away later in the CPU online callback. But that's a horrible hack and not required at all because RAPL becomes functional for perf only in the CPU online callback. That's correct because user space is not yet informed about the CPU being onlined, so nothing caan rely on RAPL being available on that particular CPU. Move the allocation to the CPU online callback and simplify the hotplug handling. At this point the package mapping is established and correct. This also adds a missing check for available package data in the event_init() function. Reported-by: Yasuaki Ishimatsu <yasu.isimatu@gmail.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Stephane Eranian <eranian@google.com> Cc: Vince Weaver <vincent.weaver@maine.edu> Fixes: 9d85eb9119f4 ("x86/smpboot: Make logical package management more robust") Link: http://lkml.kernel.org/r/20170131230141.212593966@linutronix.de Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'net/sctp/primitive.c')