linux-kernel - [tip:timers/core] perf/core: Mark hrtimers to expire in hard interrupt context

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <tip-ec0c297b253874917d7d6407117b94ef3358bf74@git.kernel.org>
Date:   Thu, 1 Aug 2019 08:54:29 -0700
From:   tip-bot for Sebastian Andrzej Siewior <tipbot@...or.com>
To:     linux-tip-commits@...r.kernel.org
Cc:     hpa@...or.com, peterz@...radead.org, mingo@...nel.org,
        tglx@...utronix.de, bigeasy@...utronix.de,
        linux-kernel@...r.kernel.org
Subject: [tip:timers/core] perf/core: Mark hrtimers to expire in hard
 interrupt context

Commit-ID:  ec0c297b253874917d7d6407117b94ef3358bf74
Gitweb:     https://git.kernel.org/tip/ec0c297b253874917d7d6407117b94ef3358bf74
Author:     Sebastian Andrzej Siewior <bigeasy@...utronix.de>
AuthorDate: Fri, 26 Jul 2019 20:30:53 +0200
Committer:  Thomas Gleixner <tglx@...utronix.de>
CommitDate: Thu, 1 Aug 2019 17:43:17 +0200

perf/core: Mark hrtimers to expire in hard interrupt context

To guarantee that the multiplexing mechanism and the hrtimer driven events
work on PREEMPT_RT enabled kernels it's required that the related hrtimers
expire in hard interrupt context. Mark them so PREEMPT_RT kernels wont
defer them to soft interrupt context.

No functional change.

[ tglx: Split out of larger combo patch. Added changelog ]

Signed-off-by: Sebastian Andrzej Siewior <bigeasy@...utronix.de>
Signed-off-by: Thomas Gleixner <tglx@...utronix.de>
Acked-by: Peter Zijlstra (Intel) <peterz@...radead.org>
Link: https://lkml.kernel.org/r/20190726185753.169509224@linutronix.de


---
 kernel/events/core.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/kernel/events/core.c b/kernel/events/core.c
index 026a14541a38..9d623e257a51 100644
--- a/kernel/events/core.c
+++ b/kernel/events/core.c
@@ -1103,7 +1103,7 @@ static void __perf_mux_hrtimer_init(struct perf_cpu_context *cpuctx, int cpu)
 	cpuctx->hrtimer_interval = ns_to_ktime(NSEC_PER_MSEC * interval);
 
 	raw_spin_lock_init(&cpuctx->hrtimer_lock);
-	hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED);
+	hrtimer_init(timer, CLOCK_MONOTONIC, HRTIMER_MODE_ABS_PINNED_HARD);
 	timer->function = perf_mux_hrtimer_handler;
 }
 
@@ -1121,7 +1121,7 @@ static int perf_mux_hrtimer_restart(struct perf_cpu_context *cpuctx)
 	if (!cpuctx->hrtimer_active) {
 		cpuctx->hrtimer_active = 1;
 		hrtimer_forward_now(timer, cpuctx->hrtimer_interval);
-		hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED);
+		hrtimer_start_expires(timer, HRTIMER_MODE_ABS_PINNED_HARD);
 	}
 	raw_spin_unlock_irqrestore(&cpuctx->hrtimer_lock, flags);
 
@@ -9491,7 +9491,7 @@ static void perf_swevent_start_hrtimer(struct perf_event *event)
 		period = max_t(u64, 10000, hwc->sample_period);
 	}
 	hrtimer_start(&hwc->hrtimer, ns_to_ktime(period),
-		      HRTIMER_MODE_REL_PINNED);
+		      HRTIMER_MODE_REL_PINNED_HARD);
 }
 
 static void perf_swevent_cancel_hrtimer(struct perf_event *event)
@@ -9513,7 +9513,7 @@ static void perf_swevent_init_hrtimer(struct perf_event *event)
 	if (!is_sampling_event(event))
 		return;
 
-	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+	hrtimer_init(&hwc->hrtimer, CLOCK_MONOTONIC, HRTIMER_MODE_REL_HARD);
 	hwc->hrtimer.function = perf_swevent_hrtimer;
 
 	/*