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Diffstat (limited to 'arch/x86/kernel/cpu/perf_event.c')
-rw-r--r--arch/x86/kernel/cpu/perf_event.c28
1 files changed, 27 insertions, 1 deletions
diff --git a/arch/x86/kernel/cpu/perf_event.c b/arch/x86/kernel/cpu/perf_event.c
index fd4db0d..5db5b7d 100644
--- a/arch/x86/kernel/cpu/perf_event.c
+++ b/arch/x86/kernel/cpu/perf_event.c
@@ -106,6 +106,7 @@ struct cpu_hw_events {
int n_events;
int n_added;
+ int n_txn;
int assign[X86_PMC_IDX_MAX]; /* event to counter assignment */
u64 tags[X86_PMC_IDX_MAX];
struct perf_event *event_list[X86_PMC_IDX_MAX]; /* in enabled order */
@@ -983,6 +984,7 @@ static int x86_pmu_enable(struct perf_event *event)
out:
cpuc->n_events = n;
cpuc->n_added += n - n0;
+ cpuc->n_txn += n - n0;
return 0;
}
@@ -1089,6 +1091,14 @@ static void x86_pmu_disable(struct perf_event *event)
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
int i;
+ /*
+ * If we're called during a txn, we don't need to do anything.
+ * The events never got scheduled and ->cancel_txn will truncate
+ * the event_list.
+ */
+ if (cpuc->group_flag & PERF_EVENT_TXN_STARTED)
+ return;
+
x86_pmu_stop(event);
for (i = 0; i < cpuc->n_events; i++) {
@@ -1379,6 +1389,7 @@ static void x86_pmu_start_txn(const struct pmu *pmu)
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
cpuc->group_flag |= PERF_EVENT_TXN_STARTED;
+ cpuc->n_txn = 0;
}
/*
@@ -1391,6 +1402,11 @@ static void x86_pmu_cancel_txn(const struct pmu *pmu)
struct cpu_hw_events *cpuc = &__get_cpu_var(cpu_hw_events);
cpuc->group_flag &= ~PERF_EVENT_TXN_STARTED;
+ /*
+ * Truncate the collected events.
+ */
+ cpuc->n_added -= cpuc->n_txn;
+ cpuc->n_events -= cpuc->n_txn;
}
/*
@@ -1419,6 +1435,12 @@ static int x86_pmu_commit_txn(const struct pmu *pmu)
*/
memcpy(cpuc->assign, assign, n*sizeof(int));
+ /*
+ * Clear out the txn count so that ->cancel_txn() which gets
+ * run after ->commit_txn() doesn't undo things.
+ */
+ cpuc->n_txn = 0;
+
return 0;
}
@@ -1717,7 +1739,11 @@ void perf_arch_fetch_caller_regs(struct pt_regs *regs, unsigned long ip, int ski
*/
regs->bp = rewind_frame_pointer(skip + 1);
regs->cs = __KERNEL_CS;
- local_save_flags(regs->flags);
+ /*
+ * We abuse bit 3 to pass exact information, see perf_misc_flags
+ * and the comment with PERF_EFLAGS_EXACT.
+ */
+ regs->flags = 0;
}
unsigned long perf_instruction_pointer(struct pt_regs *regs)
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