Use 'trigger' to model operations which need to be executed when
an event (a signal, for example) is observed.
States and transits:
OFF--(on)--> READY --(toggle)--> TOGGLED
^ |
| (ready)
| |
\__________________/
is_toggled and is_ready are two key functions to query the state of
a trigger. is_toggled means the event already happen; is_ready means the
trigger is waiting for the event.
Signed-off-by: Wang Nan <wangn...@huawei.com>
Cc: Adrian Hunter <adrian.hun...@intel.com>
Cc: He Kuang <heku...@huawei.com>
Cc: Jiri Olsa <jo...@kernel.org>
Cc: Masami Hiramatsu <mhira...@kernel.org>
Cc: Namhyung Kim <namhy...@kernel.org>
Cc: Zefan Li <lize...@huawei.com>
Cc: pi3or...@163.com
---
tools/perf/builtin-record.c | 67 +++++++--------------------
tools/perf/util/trigger.h | 109 ++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 126 insertions(+), 50 deletions(-)
create mode 100644 tools/perf/util/trigger.h
diff --git a/tools/perf/builtin-record.c b/tools/perf/builtin-record.c
index 5b4758a..ad37f69 100644
--- a/tools/perf/builtin-record.c
+++ b/tools/perf/builtin-record.c
@@ -34,6 +34,7 @@
#include "util/parse-regs-options.h"
#include "util/llvm-utils.h"
#include "util/bpf-loader.h"
+#include "util/trigger.h"
#include "asm/bug.h"
#include <unistd.h>
@@ -127,44 +128,8 @@ static volatile int done;
static volatile int signr = -1;
static volatile int child_finished;
-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;
+static DEFINE_TRIGGER(auxtrace_snapshot);
static void sig_handler(int sig)
{
@@ -282,11 +247,12 @@ static void record__read_auxtrace_snapshot(struct record
*rec)
{
pr_debug("Recording AUX area tracing snapshot\n");
if (record__auxtrace_read_snapshot_all(rec) < 0) {
- auxtrace_snapshot_err = -1;
+ auxtrace_snapshot_error();
} else {
- auxtrace_snapshot_err =
auxtrace_record__snapshot_finish(rec->itr);
- if (!auxtrace_snapshot_err)
- auxtrace_snapshot_enable();
+ if (auxtrace_record__snapshot_finish(rec->itr))
+ auxtrace_snapshot_error();
+ else
+ auxtrace_snapshot_ready();
}
}
@@ -815,21 +781,21 @@ static int __cmd_record(struct record *rec, int argc,
const char **argv)
perf_evlist__enable(rec->evlist);
}
- auxtrace_snapshot_enable();
+ auxtrace_snapshot_ready();
for (;;) {
unsigned long long hits = rec->samples;
if (record__mmap_read_all(rec) < 0) {
- auxtrace_snapshot_disable();
+ auxtrace_snapshot_error();
err = -1;
goto out_child;
}
if (auxtrace_record__snapshot_started) {
auxtrace_record__snapshot_started = 0;
- if (!auxtrace_snapshot_err)
+ if (!auxtrace_snapshot_is_error())
record__read_auxtrace_snapshot(rec);
- if (auxtrace_snapshot_err) {
+ if (auxtrace_snapshot_is_error()) {
pr_err("AUX area tracing snapshot failed\n");
err = -1;
goto out_child;
@@ -858,12 +824,12 @@ 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_disable();
+ auxtrace_snapshot_off();
perf_evlist__disable(rec->evlist);
disabled = true;
}
}
- auxtrace_snapshot_disable();
+ auxtrace_snapshot_off();
if (forks && workload_exec_errno) {
char msg[STRERR_BUFSIZE];
@@ -1447,9 +1413,10 @@ out_symbol_exit:
static void snapshot_sig_handler(int sig __maybe_unused)
{
- if (!auxtrace_snapshot_is_enabled())
+ if (!auxtrace_snapshot_is_ready())
return;
- auxtrace_snapshot_disable();
- auxtrace_snapshot_err = auxtrace_record__snapshot_start(record.itr);
+ auxtrace_snapshot_toggle();
auxtrace_record__snapshot_started = 1;
+ if (auxtrace_record__snapshot_start(record.itr))
+ auxtrace_snapshot_error();
}
diff --git a/tools/perf/util/trigger.h b/tools/perf/util/trigger.h
new file mode 100644
index 0000000..89a30e9
--- /dev/null
+++ b/tools/perf/util/trigger.h
@@ -0,0 +1,109 @@
+#ifndef __TRIGGER_H_
+#define __TRIGGER_H_ 1
+
+#include "util/debug.h"
+#include "asm/bug.h"
+
+/*
+ * Use trigger to model operations which need to be executed when
+ * an event (a signal, for example) is observed.
+ *
+ * States and transits:
+ *
+ *
+ * OFF--(on)--> READY --(toggle)--> TOGGLED
+ * ^ |
+ * | (ready)
+ * | |
+ * \__________________/
+ *
+ * is_toggled and is_ready are two key functions to query the state of
+ * a trigger. is_toggled means the event already happen; is_ready means the
+ * trigger is waiting for the event.
+ */
+
+struct trigger {
+ volatile enum {
+ TRIGGER_ERROR = -2,
+ TRIGGER_OFF = -1,
+ TRIGGER_READY = 0,
+ TRIGGER_TOGGLED = 1,
+ } state;
+ const char *name;
+};
+
+#define TRIGGER_WARN_ONCE(t, exp) \
+ WARN_ONCE(t->state != exp, "trigger '%s' state transist error: %d in
%s()\n", \
+ t->name, t->state, __func__)
+
+static inline bool trigger_is_available(struct trigger *t)
+{
+ return t->state >= 0;
+}
+
+static inline bool trigger_is_error(struct trigger *t)
+{
+ return t->state <= TRIGGER_ERROR;
+}
+
+static inline void trigger_on(struct trigger *t)
+{
+ TRIGGER_WARN_ONCE(t, TRIGGER_OFF);
+ t->state = TRIGGER_READY;
+}
+
+static inline void trigger_ready(struct trigger *t)
+{
+ if (!trigger_is_available(t))
+ return;
+ t->state = TRIGGER_READY;
+}
+
+static inline void trigger_toggle(struct trigger *t)
+{
+ if (!trigger_is_available(t))
+ return;
+ TRIGGER_WARN_ONCE(t, TRIGGER_READY);
+ t->state = TRIGGER_TOGGLED;
+}
+
+static inline void trigger_off(struct trigger *t)
+{
+ if (!trigger_is_available(t))
+ return;
+ t->state = TRIGGER_OFF;
+}
+
+static inline void trigger_error(struct trigger *t)
+{
+ t->state = TRIGGER_ERROR;
+}
+
+static inline bool trigger_is_ready(struct trigger *t)
+{
+ return t->state == TRIGGER_READY;
+}
+
+static inline bool trigger_is_toggled(struct trigger *t)
+{
+ return t->state == TRIGGER_TOGGLED;
+}
+
+#define __TRIGGER_VAR(n) n##_state
+#define __DEF_TRIGGER_VOID_FUNC(n, op) \
+static inline void n##_##op(void) {trigger_##op(&__TRIGGER_VAR(n)); }
+#define __DEF_TRIGGER_BOOL_FUNC(n, op) \
+static inline bool n##_##op(void) {return trigger_##op(&__TRIGGER_VAR(n)); }
+
+#define DEFINE_TRIGGER(n) \
+struct trigger n##_state = {.state = TRIGGER_OFF, .name = #n}; \
+__DEF_TRIGGER_VOID_FUNC(n, on) \
+__DEF_TRIGGER_VOID_FUNC(n, ready) \
+__DEF_TRIGGER_VOID_FUNC(n, toggle) \
+__DEF_TRIGGER_VOID_FUNC(n, off) \
+__DEF_TRIGGER_VOID_FUNC(n, error) \
+__DEF_TRIGGER_BOOL_FUNC(n, is_ready) \
+__DEF_TRIGGER_BOOL_FUNC(n, is_toggled) \
+__DEF_TRIGGER_BOOL_FUNC(n, is_error)
+
+#endif
--
1.8.3.4
