From 7fbfe22cf4cfe01a88704dd76ca65d108039d297 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Mon, 14 Oct 2019 20:13:51 -0300 Subject: [PATCH] perf trace: Filter own pid to avoid a feedback look in 'perf trace record -a' MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit When doing a system wide 'perf trace record' we need, just like in 'perf trace' live mode, to filter out perf trace's own pid, so set up a tracepoint filter for the raw_syscalls tracepoints right after adding them to the argv array that is set up to then call cmd_record(). Reported-by: Andi Kleen Cc: Adrian Hunter Cc: David Ahern Cc: Jiri Olsa Cc: Luis Cláudio Gonçalves Cc: Namhyung Kim Link: https://lkml.kernel.org/n/tip-uysx5w8f2y5ndoln5cq370tv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-trace.c | 24 ++++++++++++++++-------- 1 file changed, 16 insertions(+), 8 deletions(-) diff --git a/tools/perf/builtin-trace.c b/tools/perf/builtin-trace.c index 467e18e6f8ec..cdee22dac2b3 100644 --- a/tools/perf/builtin-trace.c +++ b/tools/perf/builtin-trace.c @@ -2796,21 +2796,23 @@ static int trace__record(struct trace *trace, int argc, const char **argv) "-m", "1024", "-c", "1", }; - + pid_t pid = getpid(); + char *filter = asprintf__tp_filter_pids(1, &pid); const char * const sc_args[] = { "-e", }; unsigned int sc_args_nr = ARRAY_SIZE(sc_args); const char * const majpf_args[] = { "-e", "major-faults" }; unsigned int majpf_args_nr = ARRAY_SIZE(majpf_args); const char * const minpf_args[] = { "-e", "minor-faults" }; unsigned int minpf_args_nr = ARRAY_SIZE(minpf_args); + int err = -1; - /* +1 is for the event string below */ - rec_argc = ARRAY_SIZE(record_args) + sc_args_nr + 1 + + /* +3 is for the event string below and the pid filter */ + rec_argc = ARRAY_SIZE(record_args) + sc_args_nr + 3 + majpf_args_nr + minpf_args_nr + argc; rec_argv = calloc(rec_argc + 1, sizeof(char *)); - if (rec_argv == NULL) - return -ENOMEM; + if (rec_argv == NULL || filter == NULL) + goto out_free; j = 0; for (i = 0; i < ARRAY_SIZE(record_args); i++) @@ -2827,11 +2829,13 @@ static int trace__record(struct trace *trace, int argc, const char **argv) rec_argv[j++] = "syscalls:sys_enter,syscalls:sys_exit"; else { pr_err("Neither raw_syscalls nor syscalls events exist.\n"); - free(rec_argv); - return -1; + goto out_free; } } + rec_argv[j++] = "--filter"; + rec_argv[j++] = filter; + if (trace->trace_pgfaults & TRACE_PFMAJ) for (i = 0; i < majpf_args_nr; i++) rec_argv[j++] = majpf_args[i]; @@ -2843,7 +2847,11 @@ static int trace__record(struct trace *trace, int argc, const char **argv) for (i = 0; i < (unsigned int)argc; i++) rec_argv[j++] = argv[i]; - return cmd_record(j, rec_argv); + err = cmd_record(j, rec_argv); +out_free: + free(filter); + free(rec_argv); + return err; } static size_t trace__fprintf_thread_summary(struct trace *trace, FILE *fp);