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Subject[tip:bkl/core] pm_qos: remove BKL
Commit-ID:  e6fe07a014c7a3466dcd1a387a9ac04d84c2703c
Gitweb: http://git.kernel.org/tip/e6fe07a014c7a3466dcd1a387a9ac04d84c2703c
Author: Jonathan Corbet <corbet@lwn.net>
AuthorDate: Thu, 6 Aug 2009 13:22:40 -0600
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Wed, 14 Oct 2009 15:31:10 +0200

pm_qos: remove BKL

pm_qos_power_open got its lock_kernel() calls from the open() pushdown. A
look at the code shows that the only global resources accessed are
pm_qos_array and "name". pm_qos_array doesn't change (things pointed to
therein do change, but they are atomics and/or are protected by
pm_qos_lock). Accesses to "name" are totally unprotected with or without
the BKL; that will be fixed shortly. The BKL is not helpful here; take it
out.

Signed-off-by: Jonathan Corbet <corbet@lwn.net>
LKML-Reference: <20091010153349.071381158@linutronix.de>
Acked-by: Mark Gross <mgross@linux.intel.com>
Reviewed-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>

---
kernel/pm_qos_params.c | 8 +-------
1 files changed, 1 insertions(+), 7 deletions(-)

diff --git a/kernel/pm_qos_params.c b/kernel/pm_qos_params.c
index dfdec52..d96b83e 100644
--- a/kernel/pm_qos_params.c
+++ b/kernel/pm_qos_params.c
@@ -29,7 +29,6 @@

#include <linux/pm_qos_params.h>
#include <linux/sched.h>
-#include <linux/smp_lock.h>
#include <linux/spinlock.h>
#include <linux/slab.h>
#include <linux/time.h>
@@ -352,20 +351,15 @@ static int pm_qos_power_open(struct inode *inode, struct file *filp)
int ret;
long pm_qos_class;

- lock_kernel();
pm_qos_class = find_pm_qos_object_by_minor(iminor(inode));
if (pm_qos_class >= 0) {
filp->private_data = (void *)pm_qos_class;
sprintf(name, "process_%d", current->pid);
ret = pm_qos_add_requirement(pm_qos_class, name,
PM_QOS_DEFAULT_VALUE);
- if (ret >= 0) {
- unlock_kernel();
+ if (ret >= 0)
return 0;
- }
}
- unlock_kernel();
-
return -EPERM;
}


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