[tip:perf/core] perf/x86/intel/ds: Extract code of event update in short period

tip-bot for Kan Liang
2019-04-16T11:35:58Z

Commit-ID: 477f00f9617009a9a3a9271885231573b728ca4f
Gitweb: https://git.kernel.org/tip/477f00f9617009a9a3a9271885231573b728ca4f
Author: Kan Liang <kan.liang@linux.intel.com>
AuthorDate: Tue, 2 Apr 2019 12:45:01 -0700
Committer: Ingo Molnar <mingo@kernel.org>
CommitDate: Tue, 16 Apr 2019 12:19:39 +0200

perf/x86/intel/ds: Extract code of event update in short period

The drain_pebs() could be called twice in a short period for auto-reload
event in pmu::read(). The intel_pmu_save_and_restart_reload() should be
called to update the event->count.

This case should also be handled on Icelake. Extract the code for
later reuse.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
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: acme@kernel.org
Cc: jolsa@kernel.org
Link: https://lkml.kernel.org/r/20190402194509.2832-5-kan.liang@linux.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
---
arch/x86/events/intel/ds.c | 33 ++++++++++++++++++++-------------
1 file changed, 20 insertions(+), 13 deletions(-)

diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 2f80b7e282ff..9ac73860645d 100644
--- a/arch/x86/events/intel/ds.c
+++ b/arch/x86/events/intel/ds.c
@@ -1491,6 +1491,25 @@ static void intel_pmu_drain_pebs_core(struct pt_regs *iregs)
__intel_pmu_pebs_event(event, iregs, at, top, 0, n);
}

+static void intel_pmu_pebs_event_update_no_drain(struct cpu_hw_events *cpuc, int size)
+{
+ struct perf_event *event;
+ int bit;
+
+ /*
+ * The drain_pebs() could be called twice in a short period
+ * for auto-reload event in pmu::read(). There are no
+ * overflows have happened in between.
+ * It needs to call intel_pmu_save_and_restart_reload() to
+ * update the event->count for this case.
+ */
+ for_each_set_bit(bit, (unsigned long *)&cpuc->pebs_enabled, size) {
+ event = cpuc->events[bit];
+ if (event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD)
+ intel_pmu_save_and_restart_reload(event, 0);
+ }
+}
+
static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
{
struct cpu_hw_events *cpuc = this_cpu_ptr(&cpu_hw_events);
@@ -1518,19 +1537,7 @@ static void intel_pmu_drain_pebs_nhm(struct pt_regs *iregs)
}

if (unlikely(base >= top)) {
- /*
- * The drain_pebs() could be called twice in a short period
- * for auto-reload event in pmu::read(). There are no
- * overflows have happened in between.
- * It needs to call intel_pmu_save_and_restart_reload() to
- * update the event->count for this case.
- */
- for_each_set_bit(bit, (unsigned long *)&cpuc->pebs_enabled,
- size) {
- event = cpuc->events[bit];
- if (event->hw.flags & PERF_X86_EVENT_AUTO_RELOAD)
- intel_pmu_save_and_restart_reload(event, 0);
- }
+ intel_pmu_pebs_event_update_no_drain(cpuc, size);
return;
}