From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
To: Peter Zijlstra <peterz@infradead.org>
Cc: linux-kernel@vger.kernel.org, Andy Lutomirski <luto@kernel.org>,
Thomas Gleixner <tglx@linutronix.de>,
Ingo Molnar <mingo@redhat.com>, Borislav Petkov <bp@alien8.de>,
x86@kernel.org, "H . Peter Anvin " <hpa@zytor.com>
Subject: [PATCH v2] x86/entry: Use should_resched() in idtentry_exit_cond_resched()
Date: Wed, 1 Jul 2020 10:35:53 +0200 [thread overview]
Message-ID: <20200701083553.fuy42cllxvx3bkzp@linutronix.de> (raw)
In-Reply-To: <20200630120059.x5p6uh4hzgqrgwuo@linutronix.de>
The TIF_NEED_RESCHED bit is inlined on x86 into the preemption counter.
By using should_resched(0) instead of need_resched() the same check can
be performed which uses the same variable as 'preempt_count()` which was
issued before.
Use should_resched(0) instead need_resched().
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
---
v1…v2: Use should_resched() but keep the !preempt_count() check.
arch/x86/entry/common.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/x86/entry/common.c b/arch/x86/entry/common.c
index bd3f14175193c..0bb6966f62738 100644
--- a/arch/x86/entry/common.c
+++ b/arch/x86/entry/common.c
@@ -615,11 +615,11 @@ static void idtentry_exit_cond_resched(struct pt_regs *regs, bool may_sched)
if (may_sched && !preempt_count()) {
/* Sanity check RCU and thread stack */
rcu_irq_exit_check_preempt();
if (IS_ENABLED(CONFIG_DEBUG_ENTRY))
WARN_ON_ONCE(!on_thread_stack());
- if (need_resched())
+ if (should_resched(0))
preempt_schedule_irq();
}
/* Covers both tracing and lockdep */
trace_hardirqs_on();
}
--
2.27.0
next prev parent reply other threads:[~2020-07-01 8:35 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-06-30 10:22 [PATCH 0/2] x86/entry: Tiny idtentry_exit_cond_resched() cleanup Sebastian Andrzej Siewior
2020-06-30 10:22 ` [PATCH 1/2] x86/entry: Use should_resched() in idtentry_exit_cond_resched() Sebastian Andrzej Siewior
2020-06-30 11:10 ` Peter Zijlstra
2020-06-30 12:00 ` Sebastian Andrzej Siewior
2020-07-01 8:35 ` Sebastian Andrzej Siewior [this message]
2020-06-30 10:22 ` [PATCH 2/2] x86/entry: Remove `regs' parameter from idtentry_exit_cond_resched() Sebastian Andrzej Siewior
2020-06-30 11:14 ` Peter Zijlstra
2020-06-30 12:09 ` Sebastian Andrzej Siewior
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