From d4db3f164529013b11a171bb1bd38e8681ddaec8 Mon Sep 17 00:00:00 2001 From: Arnaldo Carvalho de Melo Date: Sun, 27 Dec 2009 21:36:57 -0200 Subject: [PATCH] perf record: We should fork only if a program was specified to run MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit IOW: Now 'perf record -a' works, this was a bug introduced in: 856e96608a72412d319e498a3a7c557571f811bd "perf record: Properly synchronize child creation" Also fix the -C usage, i.e. allow for profiling all the tasks in one CPU. Reported-by: Pekka Enberg Signed-off-by: Arnaldo Carvalho de Melo Cc: Frédéric Weisbecker Cc: Mike Galbraith Cc: Peter Zijlstra Cc: Paul Mackerras LKML-Reference: <1261957026-15580-1-git-send-email-acme@infradead.org> Signed-off-by: Ingo Molnar --- tools/perf/builtin-record.c | 14 ++++++++------ 1 file changed, 8 insertions(+), 6 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index 63136d0534d4..265425322734 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -402,7 +402,7 @@ static void atexit_header(void) perf_header__write(&session->header, output, true); } -static int __cmd_record(int argc __used, const char **argv) +static int __cmd_record(int argc, const char **argv) { int i, counter; struct stat st; @@ -411,6 +411,7 @@ static int __cmd_record(int argc __used, const char **argv) int err; unsigned long waking = 0; int child_ready_pipe[2], go_pipe[2]; + const bool forks = target_pid == -1 && argc > 0; char buf; page_size = sysconf(_SC_PAGE_SIZE); @@ -422,7 +423,7 @@ static int __cmd_record(int argc __used, const char **argv) signal(SIGCHLD, sig_handler); signal(SIGINT, sig_handler); - if (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0) { + if (forks && (pipe(child_ready_pipe) < 0 || pipe(go_pipe) < 0)) { perror("failed to create pipes"); exit(-1); } @@ -483,7 +484,7 @@ static int __cmd_record(int argc __used, const char **argv) atexit(atexit_header); - if (target_pid == -1) { + if (forks) { pid = fork(); if (pid < 0) { perror("failed to fork"); @@ -550,7 +551,7 @@ static int __cmd_record(int argc __used, const char **argv) return err; } - if (!system_wide) + if (!system_wide && profile_cpu == -1) event__synthesize_thread(pid, process_synthesized_event, session); else @@ -569,7 +570,8 @@ static int __cmd_record(int argc __used, const char **argv) /* * Let the child rip */ - close(go_pipe[1]); + if (forks) + close(go_pipe[1]); for (;;) { int hits = samples; @@ -667,7 +669,7 @@ int cmd_record(int argc, const char **argv, const char *prefix __used) argc = parse_options(argc, argv, options, record_usage, PARSE_OPT_STOP_AT_NON_OPTION); - if (!argc && target_pid == -1 && (!system_wide || profile_cpu == -1)) + if (!argc && target_pid == -1 && !system_wide && profile_cpu == -1) usage_with_options(record_usage, options); symbol__init();