81 lines
2.7 KiB
Diff
81 lines
2.7 KiB
Diff
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From 05cedc69771d7e1179baf0d2b2bf66315f478983 Mon Sep 17 00:00:00 2001
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From: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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Date: Mon, 21 Nov 2016 19:26:15 +0100
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Subject: [PATCH 042/365] locking/percpu-rwsem: use swait for the wating writer
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Use struct swait_queue_head instead of wait_queue_head_t for the waiting
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writer. The swait implementation is smaller and lightweight compared to
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wait_queue_head_t.
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Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
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---
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include/linux/percpu-rwsem.h | 6 +++---
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kernel/locking/percpu-rwsem.c | 6 +++---
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2 files changed, 6 insertions(+), 6 deletions(-)
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diff --git a/include/linux/percpu-rwsem.h b/include/linux/percpu-rwsem.h
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index 5b2e6159b744..82d54a4b9988 100644
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--- a/include/linux/percpu-rwsem.h
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+++ b/include/linux/percpu-rwsem.h
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@@ -4,7 +4,7 @@
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#include <linux/atomic.h>
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#include <linux/rwsem.h>
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#include <linux/percpu.h>
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-#include <linux/wait.h>
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+#include <linux/swait.h>
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#include <linux/rcu_sync.h>
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#include <linux/lockdep.h>
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@@ -12,7 +12,7 @@ struct percpu_rw_semaphore {
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struct rcu_sync rss;
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unsigned int __percpu *read_count;
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struct rw_semaphore rw_sem;
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- wait_queue_head_t writer;
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+ struct swait_queue_head writer;
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int readers_block;
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};
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@@ -22,7 +22,7 @@ static struct percpu_rw_semaphore name = { \
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.rss = __RCU_SYNC_INITIALIZER(name.rss, RCU_SCHED_SYNC), \
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.read_count = &__percpu_rwsem_rc_##name, \
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.rw_sem = __RWSEM_INITIALIZER(name.rw_sem), \
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- .writer = __WAIT_QUEUE_HEAD_INITIALIZER(name.writer), \
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+ .writer = __SWAIT_QUEUE_HEAD_INITIALIZER(name.writer), \
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}
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extern int __percpu_down_read(struct percpu_rw_semaphore *, int);
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diff --git a/kernel/locking/percpu-rwsem.c b/kernel/locking/percpu-rwsem.c
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index ce182599cf2e..2ad3a1e8344c 100644
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--- a/kernel/locking/percpu-rwsem.c
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+++ b/kernel/locking/percpu-rwsem.c
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@@ -18,7 +18,7 @@ int __percpu_init_rwsem(struct percpu_rw_semaphore *sem,
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/* ->rw_sem represents the whole percpu_rw_semaphore for lockdep */
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rcu_sync_init(&sem->rss, RCU_SCHED_SYNC);
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__init_rwsem(&sem->rw_sem, name, rwsem_key);
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- init_waitqueue_head(&sem->writer);
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+ init_swait_queue_head(&sem->writer);
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sem->readers_block = 0;
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return 0;
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}
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@@ -103,7 +103,7 @@ void __percpu_up_read(struct percpu_rw_semaphore *sem)
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__this_cpu_dec(*sem->read_count);
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/* Prod writer to recheck readers_active */
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- wake_up(&sem->writer);
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+ swake_up(&sem->writer);
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}
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EXPORT_SYMBOL_GPL(__percpu_up_read);
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@@ -160,7 +160,7 @@ void percpu_down_write(struct percpu_rw_semaphore *sem)
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*/
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/* Wait for all now active readers to complete. */
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- wait_event(sem->writer, readers_active_check(sem));
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+ swait_event(sem->writer, readers_active_check(sem));
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}
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EXPORT_SYMBOL_GPL(percpu_down_write);
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--
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2.28.0
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