linux-kernel - [PATCH v3 33/57] perf: Simplify perf_adjust_freq_unthr

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Message-ID: <20230612093539.895253662@infradead.org>
Date:   Mon, 12 Jun 2023 11:07:46 +0200
From:   Peter Zijlstra <peterz@...radead.org>
To:     torvalds@...ux-foundation.org, keescook@...omium.org,
        gregkh@...uxfoundation.org, pbonzini@...hat.com
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Subject: [PATCH v3 33/57] perf: Simplify perf_adjust_freq_unthr_context()


Signed-off-by: Peter Zijlstra (Intel) <peterz@...radead.org>
---
 kernel/events/core.c |   10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -4100,7 +4100,7 @@ perf_adjust_freq_unthr_context(struct pe
 	if (!(ctx->nr_freq || unthrottle))
 		return;
 
-	raw_spin_lock(&ctx->lock);
+	guard(raw_spinlock)(&ctx->lock);
 
 	list_for_each_entry_rcu(event, &ctx->event_list, event_entry) {
 		if (event->state != PERF_EVENT_STATE_ACTIVE)
@@ -4110,7 +4110,7 @@ perf_adjust_freq_unthr_context(struct pe
 		if (!event_filter_match(event))
 			continue;
 
-		perf_pmu_disable(event->pmu);
+		guard(perf_pmu_disable)(event->pmu);
 
 		hwc = &event->hw;
 
@@ -4121,7 +4121,7 @@ perf_adjust_freq_unthr_context(struct pe
 		}
 
 		if (!event->attr.freq || !event->attr.sample_freq)
-			goto next;
+			continue;
 
 		/*
 		 * stop the event and update event->count
@@ -4143,11 +4143,7 @@ perf_adjust_freq_unthr_context(struct pe
 			perf_adjust_period(event, period, delta, false);
 
 		event->pmu->start(event, delta > 0 ? PERF_EF_RELOAD : 0);
-	next:
-		perf_pmu_enable(event->pmu);
 	}
-
-	raw_spin_unlock(&ctx->lock);
 }
 
 /*