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>

diff --git a/arch/x86/events/intel/ds.c b/arch/x86/events/intel/ds.c
index 2f80b7e282ff21349e0d268757a092db155f5f50..9ac73860645df96dcc945e479660f720ef70a349 100644 (file)
--- 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;
        }