>From 5c9a0c1510ec29c1e148f66f3c111f52f7565df1 Mon Sep 17 00:00:00 2001
From: Nicholas Mc Guire <der.herr@xxxxxxx>
Date: Fri, 22 Nov 2013 02:41:48 -0500
Subject: [PATCH] migrate_disable pushd down in rt_read_trylock
No need to migrate_disable before requesting the lock and no need to
speculatively disable/enable on every recursive call. migration_disable
can be done at the latest point in the code before returning an acquired
``lock.
patch is on top of 3.12-rt2
No change of functionality
Signed-off-by: Nicholas Mc Guire <der.herr@xxxxxxx>
---
kernel/rt.c | 7 +++----
1 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/kernel/rt.c b/kernel/rt.c
index 71d26a4..54211f0 100644
--- a/kernel/rt.c
+++ b/kernel/rt.c
@@ -212,19 +212,18 @@ int __lockfunc rt_read_trylock(rwlock_t *rwlock)
* but not when read_depth == 0 which means that the lock is
* write locked.
*/
- migrate_disable();
if (rt_mutex_owner(lock) != current) {
ret = rt_mutex_trylock(lock);
- if (ret)
+ if (ret) {
rwlock_acquire(&rwlock->dep_map, 0, 1, _RET_IP_);
+ migrate_disable();
+ }
} else if (!rwlock->read_depth) {
ret = 0;
}
if (ret)
rwlock->read_depth++;
- else
- migrate_enable();
return ret;
}
--
1.7.2.5
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