Merge branch 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fixes from Ingo Molnar:
 "Two hw-enablement patches, two race fixes, three fixes for regressions
  of semantics, plus a number of tooling fixes"

* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/intel: Add proper condition to run sched_task callbacks
  perf/core: Fix locking for children siblings group read
  perf/core: Fix scheduling regression of pinned groups
  perf/x86/intel: Fix debug_store reset field for freq events
  perf/x86/intel: Add Goldmont Plus CPU PMU support
  perf/x86/intel: Enable C-state residency events for Apollo Lake
  perf symbols: Accept zero as the kernel base address
  Revert "perf/core: Drop kernel samples even though :u is specified"
  perf annotate: Fix broken arrow at row 0 connecting jmp instruction to its target
  perf evsel: State in the default event name if attr.exclude_kernel is set
  perf evsel: Fix attr.exclude_kernel setting for default cycles:p

1 files changed, 12 insertions, 21 deletions

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 1538df9..426c2ff 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1452,6 +1452,13 @@ static enum event_type_t get_event_type(struct perf_event *event)
 
 	lockdep_assert_held(&ctx->lock);
 
+	/*
+	 * It's 'group type', really, because if our group leader is
+	 * pinned, so are we.
+	 */
+	if (event->group_leader != event)
+		event = event->group_leader;
+
 	event_type = event->attr.pinned ? EVENT_PINNED : EVENT_FLEXIBLE;
 	if (!ctx->task)
 		event_type |= EVENT_CPU;
@@ -4378,7 +4385,9 @@ EXPORT_SYMBOL_GPL(perf_event_read_value);
 static int __perf_read_group_add(struct perf_event *leader,
 					u64 read_format, u64 *values)
 {
+	struct perf_event_context *ctx = leader->ctx;
 	struct perf_event *sub;
+	unsigned long flags;
 	int n = 1; /* skip @nr */
 	int ret;
 
@@ -4408,12 +4417,15 @@ static int __perf_read_group_add(struct perf_event *leader,
 	if (read_format & PERF_FORMAT_ID)
 		values[n++] = primary_event_id(leader);
 
+	raw_spin_lock_irqsave(&ctx->lock, flags);
+
 	list_for_each_entry(sub, &leader->sibling_list, group_entry) {
 		values[n++] += perf_event_count(sub);
 		if (read_format & PERF_FORMAT_ID)
 			values[n++] = primary_event_id(sub);
 	}
 
+	raw_spin_unlock_irqrestore(&ctx->lock, flags);
 	return 0;
 }
 
@@ -7321,21 +7333,6 @@ int perf_event_account_interrupt(struct perf_event *event)
 	return __perf_event_account_interrupt(event, 1);
 }
 
-static bool sample_is_allowed(struct perf_event *event, struct pt_regs *regs)
-{
-	/*
-	 * Due to interrupt latency (AKA "skid"), we may enter the
-	 * kernel before taking an overflow, even if the PMU is only
-	 * counting user events.
-	 * To avoid leaking information to userspace, we must always
-	 * reject kernel samples when exclude_kernel is set.
-	 */
-	if (event->attr.exclude_kernel && !user_mode(regs))
-		return false;
-
-	return true;
-}
-
 /*
  * Generic event overflow handling, sampling.
  */
@@ -7357,12 +7354,6 @@ static int __perf_event_overflow(struct perf_event *event,
 	ret = __perf_event_account_interrupt(event, throttle);
 
 	/*
-	 * For security, drop the skid kernel samples if necessary.
-	 */
-	if (!sample_is_allowed(event, regs))
-		return ret;
-
-	/*
 	 * XXX event_limit might not quite work as expected on inherited
 	 * events
 	 */