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authorAlexander Shishkin <alexander.shishkin@linux.intel.com>2017-03-30 18:39:56 +0300
committerIngo Molnar <mingo@kernel.org>2017-08-29 16:09:24 +0300
commit8d4e6c4caa12dafbcba138e5450b7af17b0b2194 (patch)
treea9b6c4f3076bd27f9a87fb67a2907c9a0a3c5cbd /include/linux/perf_event.h
parente0563e049531973e665db853e825a4efed9f881d (diff)
downloadlinux-8d4e6c4caa12dafbcba138e5450b7af17b0b2194.tar.xz
perf/core, pt, bts: Get rid of itrace_started
I just noticed that hw.itrace_started and hw.config are aliased to the same location. Now, the PT driver happens to use both, which works out fine by sheer luck: - STORE(hw.itrace_start) is ordered before STORE(hw.config), in the program order, although there are no compiler barriers to ensure that, - to the perf_log_itrace_start() hw.itrace_start looks set at the same time as when it is intended to be set because both stores happen in the same path, - hw.config is never reset to zero in the PT driver. Now, the use of hw.config by the PT driver makes more sense (it being a HW PMU) than messing around with itrace_started, which is an awkward API to begin with. This patch replaces hw.itrace_started with an attach_state bit and an API call for the PMU drivers to use to communicate the condition. Signed-off-by: Alexander Shishkin <alexander.shishkin@linux.intel.com> Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@infradead.org> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: vince@deater.net Link: http://lkml.kernel.org/r/20170330153956.25994-1-alexander.shishkin@linux.intel.com Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'include/linux/perf_event.h')
-rw-r--r--include/linux/perf_event.h5
1 files changed, 2 insertions, 3 deletions
diff --git a/include/linux/perf_event.h b/include/linux/perf_event.h
index c00cd4b02f32..adda0aaae6c8 100644
--- a/include/linux/perf_event.h
+++ b/include/linux/perf_event.h
@@ -147,9 +147,6 @@ struct hw_perf_event {
struct list_head cqm_groups_entry;
struct list_head cqm_group_entry;
};
- struct { /* itrace */
- int itrace_started;
- };
struct { /* amd_power */
u64 pwr_acc;
u64 ptsc;
@@ -541,6 +538,7 @@ struct swevent_hlist {
#define PERF_ATTACH_GROUP 0x02
#define PERF_ATTACH_TASK 0x04
#define PERF_ATTACH_TASK_DATA 0x08
+#define PERF_ATTACH_ITRACE 0x10
struct perf_cgroup;
struct ring_buffer;
@@ -864,6 +862,7 @@ extern int perf_aux_output_skip(struct perf_output_handle *handle,
unsigned long size);
extern void *perf_get_aux(struct perf_output_handle *handle);
extern void perf_aux_output_flag(struct perf_output_handle *handle, u64 flags);
+extern void perf_event_itrace_started(struct perf_event *event);
extern int perf_pmu_register(struct pmu *pmu, const char *name, int type);
extern void perf_pmu_unregister(struct pmu *pmu);