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| author | Paul E. McKenney <paulmck@linux.vnet.ibm.com> | 2009-08-24 09:42:01 -0700 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2009-08-24 20:37:04 +0200 |
| commit | 33f76148ced0e0618062e302d2a9614efdbd4a06 (patch) | |
| tree | 82a5c2719301bcb9f20b0597b77e91529f9ec2df | |
| parent | 7c614d6461399acca5c0ba444f5db49cb332fc08 (diff) | |
| download | linux-33f76148ced0e0618062e302d2a9614efdbd4a06.tar.bz2 | |
rcu: Add CPU-offline processing for single-node configurations
Add preemptable-RCU plugin to handle the CPU-offline
processing.
An additional plugin is forthcoming to handle multinode RCU
trees, but this current plugin works for configurations up to
32 CPUs (64 CPUs for 64-bit kernels).
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Cc: laijs@cn.fujitsu.com
Cc: dipankar@in.ibm.com
Cc: akpm@linux-foundation.org
Cc: mathieu.desnoyers@polymtl.ca
Cc: josht@linux.vnet.ibm.com
Cc: dvhltc@us.ibm.com
Cc: niv@us.ibm.com
Cc: peterz@infradead.org
Cc: rostedt@goodmis.org
LKML-Reference: <12511321213336-git-send-email->
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | kernel/rcutree.c | 2 | ||||
| -rw-r--r-- | kernel/rcutree_plugin.h | 24 |
2 files changed, 26 insertions, 0 deletions
diff --git a/kernel/rcutree.c b/kernel/rcutree.c index cc0255714075..000b07609876 100644 --- a/kernel/rcutree.c +++ b/kernel/rcutree.c @@ -84,6 +84,7 @@ extern long rcu_batches_completed_sched(void); static void cpu_quiet_msk(unsigned long mask, struct rcu_state *rsp, struct rcu_node *rnp, unsigned long flags); static void cpu_quiet_msk_finish(struct rcu_state *rsp, unsigned long flags); +static void __rcu_offline_cpu(int cpu, struct rcu_state *rsp); static void __rcu_process_callbacks(struct rcu_state *rsp, struct rcu_data *rdp); static void __call_rcu(struct rcu_head *head, @@ -920,6 +921,7 @@ static void rcu_offline_cpu(int cpu) { __rcu_offline_cpu(cpu, &rcu_sched_state); __rcu_offline_cpu(cpu, &rcu_bh_state); + rcu_preempt_offline_cpu(cpu); } #else /* #ifdef CONFIG_HOTPLUG_CPU */ diff --git a/kernel/rcutree_plugin.h b/kernel/rcutree_plugin.h index cd2ab67400c6..201334cdc200 100644 --- a/kernel/rcutree_plugin.h +++ b/kernel/rcutree_plugin.h @@ -259,6 +259,18 @@ static int rcu_preempted_readers(struct rcu_node *rnp) return !list_empty(&rnp->blocked_tasks[rnp->gpnum & 0x1]); } +#ifdef CONFIG_HOTPLUG_CPU + +/* + * Do CPU-offline processing for preemptable RCU. + */ +static void rcu_preempt_offline_cpu(int cpu) +{ + __rcu_offline_cpu(cpu, &rcu_preempt_state); +} + +#endif /* #ifdef CONFIG_HOTPLUG_CPU */ + /* * Check for a quiescent state from the current CPU. When a task blocks, * the task is recorded in the corresponding CPU's rcu_node structure, @@ -395,6 +407,18 @@ static int rcu_preempted_readers(struct rcu_node *rnp) return 0; } +#ifdef CONFIG_HOTPLUG_CPU + +/* + * Because preemptable RCU does not exist, it never needs CPU-offline + * processing. + */ +static void rcu_preempt_offline_cpu(int cpu) +{ +} + +#endif /* #ifdef CONFIG_HOTPLUG_CPU */ + /* * Because preemptable RCU does not exist, it never has any callbacks * to check. |