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| author | Paul E. McKenney <paul.mckenney@linaro.org> | 2012-01-23 17:23:35 -0800 |
|---|---|---|
| committer | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2012-02-21 09:06:05 -0800 |
| commit | c0cfbbb0d4fca14b828a7635a59784adfba8989d (patch) | |
| tree | a6201565b275d63b17df2a256e9b30c91f94cb6d /kernel/rcutree_plugin.h | |
| parent | 3d3b7db0a22085cfc05c3318b9874f7fb8266d18 (diff) | |
| download | lwn-c0cfbbb0d4fca14b828a7635a59784adfba8989d.tar.gz lwn-c0cfbbb0d4fca14b828a7635a59784adfba8989d.zip | |
rcu: No interrupt disabling for rcu_prepare_for_idle()
The rcu_prepare_for_idle() function is always called with interrupts
disabled, so there is no reason to disable interrupts again within
rcu_prepare_for_idle(). Therefore, this commit removes all of the
interrupt disabling, also removing a latent disabling-unbalance bug.
Signed-off-by: Paul E. McKenney <paul.mckenney@linaro.org>
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Diffstat (limited to 'kernel/rcutree_plugin.h')
| -rw-r--r-- | kernel/rcutree_plugin.h | 18 |
1 files changed, 1 insertions, 17 deletions
diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index 98ce17cf1fb5..5e25ee327ccb 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -2096,10 +2096,6 @@ static void rcu_cleanup_after_idle(int cpu) */ static void rcu_prepare_for_idle(int cpu) { - unsigned long flags; - - local_irq_save(flags); - /* * If there are no callbacks on this CPU, enter dyntick-idle mode. * Also reset state to avoid prejudicing later attempts. @@ -2107,7 +2103,6 @@ static void rcu_prepare_for_idle(int cpu) if (!rcu_cpu_has_callbacks(cpu)) { per_cpu(rcu_dyntick_holdoff, cpu) = jiffies - 1; per_cpu(rcu_dyntick_drain, cpu) = 0; - local_irq_restore(flags); trace_rcu_prep_idle("No callbacks"); return; } @@ -2117,7 +2112,6 @@ static void rcu_prepare_for_idle(int cpu) * refrained from disabling the scheduling-clock tick. */ if (per_cpu(rcu_dyntick_holdoff, cpu) == jiffies) { - local_irq_restore(flags); trace_rcu_prep_idle("In holdoff"); return; } @@ -2142,7 +2136,6 @@ static void rcu_prepare_for_idle(int cpu) } else if (--per_cpu(rcu_dyntick_drain, cpu) <= 0) { /* We have hit the limit, so time to give up. */ per_cpu(rcu_dyntick_holdoff, cpu) = jiffies; - local_irq_restore(flags); trace_rcu_prep_idle("Begin holdoff"); invoke_rcu_core(); /* Force the CPU out of dyntick-idle. */ return; @@ -2154,23 +2147,17 @@ static void rcu_prepare_for_idle(int cpu) */ #ifdef CONFIG_TREE_PREEMPT_RCU if (per_cpu(rcu_preempt_data, cpu).nxtlist) { - local_irq_restore(flags); rcu_preempt_qs(cpu); force_quiescent_state(&rcu_preempt_state, 0); - local_irq_save(flags); } #endif /* #ifdef CONFIG_TREE_PREEMPT_RCU */ if (per_cpu(rcu_sched_data, cpu).nxtlist) { - local_irq_restore(flags); rcu_sched_qs(cpu); force_quiescent_state(&rcu_sched_state, 0); - local_irq_save(flags); } if (per_cpu(rcu_bh_data, cpu).nxtlist) { - local_irq_restore(flags); rcu_bh_qs(cpu); force_quiescent_state(&rcu_bh_state, 0); - local_irq_save(flags); } /* @@ -2178,13 +2165,10 @@ static void rcu_prepare_for_idle(int cpu) * So try forcing the callbacks through the grace period. */ if (rcu_cpu_has_callbacks(cpu)) { - local_irq_restore(flags); trace_rcu_prep_idle("More callbacks"); invoke_rcu_core(); - } else { - local_irq_restore(flags); + } else trace_rcu_prep_idle("Callbacks drained"); - } } #endif /* #else #if !defined(CONFIG_RCU_FAST_NO_HZ) */ |