From c0bdc1c461dd5b2e492c0746708a3e0da6b13515 Mon Sep 17 00:00:00 2001 From: Wang Nan Date: Wed, 13 Apr 2016 08:21:06 +0000 Subject: [PATCH] perf record: Turns auxtrace_snapshot_enable into 3 states auxtrace_snapshot_enable has only two states (0/1). Turns it into a triple states enum so SIGUSR2 handler can safely do other works without triggering auxtrace snapshot. Signed-off-by: Wang Nan Acked-by: Adrian Hunter Acked-by: Jiri Olsa Cc: Masami Hiramatsu Cc: Namhyung Kim Cc: Zefan Li Cc: pi3orama@163.com Link: http://lkml.kernel.org/r/1460535673-159866-4-git-send-email-wangnan0@huawei.com Signed-off-by: He Kuang Signed-off-by: Arnaldo Carvalho de Melo --- tools/perf/builtin-record.c | 59 ++++++++++++++++++++++++++++++------- 1 file changed, 49 insertions(+), 10 deletions(-) diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c index eb6a199a833c..480033fb9b20 100644 --- a/tools/perf/builtin-record.c +++ b/tools/perf/builtin-record.c @@ -125,7 +125,43 @@ out: static volatile int done; static volatile int signr = -1; static volatile int child_finished; -static volatile int auxtrace_snapshot_enabled; + +static volatile enum { + AUXTRACE_SNAPSHOT_OFF = -1, + AUXTRACE_SNAPSHOT_DISABLED = 0, + AUXTRACE_SNAPSHOT_ENABLED = 1, +} auxtrace_snapshot_state = AUXTRACE_SNAPSHOT_OFF; + +static inline void +auxtrace_snapshot_on(void) +{ + auxtrace_snapshot_state = AUXTRACE_SNAPSHOT_DISABLED; +} + +static inline void +auxtrace_snapshot_enable(void) +{ + if (auxtrace_snapshot_state == AUXTRACE_SNAPSHOT_OFF) + return; + auxtrace_snapshot_state = AUXTRACE_SNAPSHOT_ENABLED; +} + +static inline void +auxtrace_snapshot_disable(void) +{ + if (auxtrace_snapshot_state == AUXTRACE_SNAPSHOT_OFF) + return; + auxtrace_snapshot_state = AUXTRACE_SNAPSHOT_DISABLED; +} + +static inline bool +auxtrace_snapshot_is_enabled(void) +{ + if (auxtrace_snapshot_state == AUXTRACE_SNAPSHOT_OFF) + return false; + return auxtrace_snapshot_state == AUXTRACE_SNAPSHOT_ENABLED; +} + static volatile int auxtrace_snapshot_err; static volatile int auxtrace_record__snapshot_started; @@ -249,7 +285,7 @@ static void record__read_auxtrace_snapshot(struct record *rec) } else { auxtrace_snapshot_err = auxtrace_record__snapshot_finish(rec->itr); if (!auxtrace_snapshot_err) - auxtrace_snapshot_enabled = 1; + auxtrace_snapshot_enable(); } } @@ -615,10 +651,13 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) signal(SIGCHLD, sig_handler); signal(SIGINT, sig_handler); signal(SIGTERM, sig_handler); - if (rec->opts.auxtrace_snapshot_mode) + + if (rec->opts.auxtrace_snapshot_mode) { signal(SIGUSR2, snapshot_sig_handler); - else + auxtrace_snapshot_on(); + } else { signal(SIGUSR2, SIG_IGN); + } session = perf_session__new(file, false, tool); if (session == NULL) { @@ -744,12 +783,12 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) perf_evlist__enable(rec->evlist); } - auxtrace_snapshot_enabled = 1; + auxtrace_snapshot_enable(); for (;;) { unsigned long long hits = rec->samples; if (record__mmap_read_all(rec) < 0) { - auxtrace_snapshot_enabled = 0; + auxtrace_snapshot_disable(); err = -1; goto out_child; } @@ -787,12 +826,12 @@ static int __cmd_record(struct record *rec, int argc, const char **argv) * disable events in this case. */ if (done && !disabled && !target__none(&opts->target)) { - auxtrace_snapshot_enabled = 0; + auxtrace_snapshot_disable(); perf_evlist__disable(rec->evlist); disabled = true; } } - auxtrace_snapshot_enabled = 0; + auxtrace_snapshot_disable(); if (forks && workload_exec_errno) { char msg[STRERR_BUFSIZE]; @@ -1358,9 +1397,9 @@ out_symbol_exit: static void snapshot_sig_handler(int sig __maybe_unused) { - if (!auxtrace_snapshot_enabled) + if (!auxtrace_snapshot_is_enabled()) return; - auxtrace_snapshot_enabled = 0; + auxtrace_snapshot_disable(); auxtrace_snapshot_err = auxtrace_record__snapshot_start(record.itr); auxtrace_record__snapshot_started = 1; }