Commit e6fe07a0 authored Aug 06, 2009 by Jonathan Corbet Committed by Thomas Gleixner Oct 14, 2009

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>

parent 80f50691

kernel/pm_qos_params.c

+1 −7

Original line number	Diff line number	Diff line
		@@ -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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