[tip: perf/urgent] perf: Simplify group_sched_in()

["tip-bot2 for Peter Zijlstra" <tip-bot2@linutronix.de>]

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID:     251ff2d49347793d348babcff745289b11910e96
Gitweb:        https://git.kernel.org/tip/251ff2d49347793d348babcff745289b11910e96
Author:        Peter Zijlstra <peterz@infradead.org>
AuthorDate:    Thu, 29 Oct 2020 16:29:15 +01:00
Committer:     Peter Zijlstra <peterz@infradead.org>
CommitterDate: Mon, 09 Nov 2020 18:12:35 +01:00

perf: Simplify group_sched_in()

Collate the error paths. Code duplication only leads to divergence and
extra bugs.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20201029162901.972161394@infradead.org
---
 kernel/events/core.c | 10 +++-------
 1 file changed, 3 insertions(+), 7 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 9a57366..f0e5268 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -2580,11 +2580,8 @@ group_sched_in(struct perf_event *group_event,
 
 	pmu->start_txn(pmu, PERF_PMU_TXN_ADD);
 
-	if (event_sched_in(group_event, cpuctx, ctx)) {
-		pmu->cancel_txn(pmu);
-		perf_mux_hrtimer_restart(cpuctx);
-		return -EAGAIN;
-	}
+	if (event_sched_in(group_event, cpuctx, ctx))
+		goto error;
 
 	/*
 	 * Schedule in siblings as one group (if any):
@@ -2613,10 +2610,9 @@ group_error:
 	}
 	event_sched_out(group_event, cpuctx, ctx);
 
+error:
 	pmu->cancel_txn(pmu);
-
 	perf_mux_hrtimer_restart(cpuctx);
-
 	return -EAGAIN;
 }