Em Wed, Apr 13, 2016 at 08:21:06AM +0000, Wang Nan escreveu:
> 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.
Adrian, can you take a look at this? Is it ok with you?
Thanks,
- Arnaldo
> Signed-off-by: Wang Nan <wangn...@huawei.com>
> Signed-off-by: He Kuang <heku...@huawei.com>
> Acked-by: Jiri Olsa <jo...@kernel.org>
> Cc: Arnaldo Carvalho de Melo <a...@redhat.com>
> Cc: Masami Hiramatsu <masami.hiramatsu...@hitachi.com>
> Cc: Namhyung Kim <namhy...@kernel.org>
> Cc: Zefan Li <lize...@huawei.com>
> Cc: pi3or...@163.com
> ---
> 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 eb6a199..480033f 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;
> }
> --
> 1.8.3.4
