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| author | Joel Fernandes <joelagnelf@nvidia.com> | 2026-07-18 13:15:36 -0400 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@kernel.org> | 2026-07-23 10:39:57 -0700 |
| commit | 34ff636f322c6d5e4f0a52338fa63a7dff09a495 (patch) | |
| tree | 7629759c1ec7148b95bc8ab3080df20a5ecd2273 /tools/perf/bench/syscall.c | |
| download | linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.tar.gz linux-stable-34ff636f322c6d5e4f0a52338fa63a7dff09a495.zip | |
scftorture: Count single_rpc offline failures in statistics outputgrafted
scf_torture_stats_print() aggregates each invoker thread's counters
into a local scf_statistics structure before printing, but the
n_single_rpc_ofl field is missing from the aggregation loop. As a
result, the "single_rpc_ofl" value printed in the statistics line is
always zero, even when smp_call_function_single() invocations for the
RPC test have failed due to offline CPUs and been counted by the
invoker threads.
Add the missing accumulation so that the printed value reflects the
actual counts.
Signed-off-by: Joel Fernandes <joelagnelf@nvidia.com>
Signed-off-by: Paul E. McKenney <paulmck@kernel.org>
Diffstat (limited to 'tools/perf/bench/syscall.c')
| -rw-r--r-- | tools/perf/bench/syscall.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/tools/perf/bench/syscall.c b/tools/perf/bench/syscall.c new file mode 100644 index 000000000..e7dc216f7 --- /dev/null +++ b/tools/perf/bench/syscall.c @@ -0,0 +1,188 @@ +/* + * + * syscall.c + * + * syscall: Benchmark for system call performance + */ +#include "../perf.h" +#include "../util/util.h" +#include <subcmd/parse-options.h> +#include "../builtin.h" +#include "bench.h" + +#include <stdio.h> +#include <sys/time.h> +#include <sys/syscall.h> +#include <sys/types.h> +#include <sys/wait.h> +#include <unistd.h> +#include <stdlib.h> + +#ifndef __NR_fork +#define __NR_fork -1 +#endif + +static int loops; + +static const struct option options[] = { + OPT_INTEGER('l', "loop", &loops, "Specify number of loops"), + OPT_END() +}; + +static const char * const bench_syscall_usage[] = { + "perf bench syscall <options>", + NULL +}; + +static void test_fork(void) +{ + pid_t pid = fork(); + + if (pid < 0) { + fprintf(stderr, "fork failed\n"); + exit(1); + } else if (pid == 0) { + exit(0); + } else { + if (waitpid(pid, NULL, 0) < 0) { + fprintf(stderr, "waitpid failed\n"); + exit(1); + } + } +} + +static void test_execve(void) +{ + const char *pathname = "/bin/true"; + char *const argv[] = { (char *)pathname, NULL }; + pid_t pid = fork(); + + if (pid < 0) { + fprintf(stderr, "fork failed\n"); + exit(1); + } else if (pid == 0) { + execve(pathname, argv, NULL); + fprintf(stderr, "execve /bin/true failed\n"); + exit(1); + } else { + if (waitpid(pid, NULL, 0) < 0) { + fprintf(stderr, "waitpid failed\n"); + exit(1); + } + } +} + +static int bench_syscall_common(int argc, const char **argv, int syscall) +{ + struct timeval start, stop, diff; + unsigned long long result_usec = 0; + const char *name = NULL; + int i; + + switch (syscall) { + case __NR_fork: + case __NR_execve: + /* Limit default loop to 10000 times to save time */ + loops = 10000; + break; + default: + loops = 10000000; + break; + } + + /* Options -l and --loops override default above */ + argc = parse_options(argc, argv, options, bench_syscall_usage, 0); + + gettimeofday(&start, NULL); + + for (i = 0; i < loops; i++) { + switch (syscall) { + case __NR_getppid: + getppid(); + break; + case __NR_getpgid: + getpgid(0); + break; + case __NR_fork: + test_fork(); + break; + case __NR_execve: + test_execve(); + default: + break; + } + } + + gettimeofday(&stop, NULL); + timersub(&stop, &start, &diff); + + switch (syscall) { + case __NR_getppid: + name = "getppid()"; + break; + case __NR_getpgid: + name = "getpgid()"; + break; + case __NR_fork: + name = "fork()"; + break; + case __NR_execve: + name = "execve()"; + break; + default: + break; + } + + switch (bench_format) { + case BENCH_FORMAT_DEFAULT: + printf("# Executed %'d %s calls\n", loops, name); + + result_usec = diff.tv_sec * 1000000; + result_usec += diff.tv_usec; + + printf(" %14s: %lu.%03lu [sec]\n\n", "Total time", + (unsigned long) diff.tv_sec, + (unsigned long) (diff.tv_usec/1000)); + + printf(" %14lf usecs/op\n", + (double)result_usec / (double)loops); + printf(" %'14d ops/sec\n", + (int)((double)loops / + ((double)result_usec / (double)1000000))); + break; + + case BENCH_FORMAT_SIMPLE: + printf("%lu.%03lu\n", + (unsigned long) diff.tv_sec, + (unsigned long) (diff.tv_usec / 1000)); + break; + + default: + /* reaching here is something disaster */ + fprintf(stderr, "Unknown format:%d\n", bench_format); + exit(1); + break; + } + + return 0; +} + +int bench_syscall_basic(int argc, const char **argv) +{ + return bench_syscall_common(argc, argv, __NR_getppid); +} + +int bench_syscall_getpgid(int argc, const char **argv) +{ + return bench_syscall_common(argc, argv, __NR_getpgid); +} + +int bench_syscall_fork(int argc, const char **argv) +{ + return bench_syscall_common(argc, argv, __NR_fork); +} + +int bench_syscall_execve(int argc, const char **argv) +{ + return bench_syscall_common(argc, argv, __NR_execve); +} |
