| Date | Sat, 10 Oct 2009 15:35:24 -0000 | From | Thomas Gleixner <> | Subject | [patch 01/28] 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> Cc: Mark Gross <mgross@linux.intel.com> Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
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; }
|