Commit-ID: 4d4c4e24cf48400a24d33feffc7cca4f4e8cabe1 Gitweb: http://git.kernel.org/tip/4d4c4e24cf48400a24d33feffc7cca4f4e8cabe1 Author: Frederic Weisbecker <fweisbec@xxxxxxxxx> AuthorDate: Fri, 22 Feb 2013 00:05:07 +0100 Committer: Frederic Weisbecker <fweisbec@xxxxxxxxx> CommitDate: Fri, 22 Feb 2013 00:05:07 +0100 irq: Remove IRQ_EXIT_OFFSET workaround The IRQ_EXIT_OFFSET trick was used to make sure the irq doesn't get preempted after we substract the HARDIRQ_OFFSET until we are entirely done with any code in irq_exit(). This workaround was necessary because some archs may call irq_exit() with irqs enabled and there is still some code in the end of this function that is not covered by the HARDIRQ_OFFSET but want to stay non-preemptible. Now that irq are always disabled in irq_exit(), the whole code is guaranteed not to be preempted. We can thus remove this hack. Signed-off-by: Frederic Weisbecker <fweisbec@xxxxxxxxx> Cc: Linus Torvalds <torvalds@xxxxxxxxxxxxxxxxxxxx> Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ingo Molnar <mingo@xxxxxxxxxx> Cc: Peter Zijlstra <peterz@xxxxxxxxxxxxx> Cc: Paul E. McKenney <paulmck@xxxxxxxxxxxxxxxxxx> --- include/linux/hardirq.h | 2 -- kernel/softirq.c | 3 +-- 2 files changed, 1 insertion(+), 4 deletions(-) diff --git a/include/linux/hardirq.h b/include/linux/hardirq.h index 29eb805..c1d6555 100644 --- a/include/linux/hardirq.h +++ b/include/linux/hardirq.h @@ -118,10 +118,8 @@ #ifdef CONFIG_PREEMPT_COUNT # define preemptible() (preempt_count() == 0 && !irqs_disabled()) -# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1) #else # define preemptible() 0 -# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET #endif #if defined(CONFIG_SMP) || defined(CONFIG_GENERIC_HARDIRQS) diff --git a/kernel/softirq.c b/kernel/softirq.c index 24a921b..f42ff97 100644 --- a/kernel/softirq.c +++ b/kernel/softirq.c @@ -343,7 +343,7 @@ void irq_exit(void) account_irq_exit_time(current); trace_hardirq_exit(); - sub_preempt_count(IRQ_EXIT_OFFSET); + sub_preempt_count(HARDIRQ_OFFSET); if (!in_interrupt() && local_softirq_pending()) invoke_softirq(); @@ -353,7 +353,6 @@ void irq_exit(void) tick_nohz_irq_exit(); #endif rcu_irq_exit(); - sched_preempt_enable_no_resched(); #ifndef __ARCH_IRQ_EXIT_IRQS_DISABLED local_irq_restore(flags); #endif -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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