diff options
author | Shaohua Li <shaohua.li@intel.com> | 2009-04-07 10:24:29 +0800 |
---|---|---|
committer | Len Brown <len.brown@intel.com> | 2009-04-07 00:02:40 -0400 |
commit | 9090589d87506c578ea1523ffd7ae7fd9424fb28 (patch) | |
tree | 215163d13dbfa514a4121594cd4c6e27fde9b911 /drivers/acpi/wakeup.c | |
parent | d508afb437daee7cf07da085b635c44a4ebf9b38 (diff) | |
download | linux-9090589d87506c578ea1523ffd7ae7fd9424fb28.tar.bz2 |
ACPI: convert acpi_device_lock spinlock to mutex
Convert acpi_device_lock to a mutex to avoid
a potential race upon access to /proc/acpi/wakeup
Delete the lock entirely in wakeup.c
since it is not necessary (and can not sleep)
Found-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/wakeup.c')
-rw-r--r-- | drivers/acpi/wakeup.c | 30 |
1 files changed, 7 insertions, 23 deletions
diff --git a/drivers/acpi/wakeup.c b/drivers/acpi/wakeup.c index 5aee8c26cc9f..88725dcdf8bc 100644 --- a/drivers/acpi/wakeup.c +++ b/drivers/acpi/wakeup.c @@ -12,12 +12,14 @@ #include "internal.h" #include "sleep.h" +/* + * We didn't lock acpi_device_lock in the file, because it invokes oops in + * suspend/resume and isn't really required as this is called in S-state. At + * that time, there is no device hotplug + **/ #define _COMPONENT ACPI_SYSTEM_COMPONENT ACPI_MODULE_NAME("wakeup_devices") -extern struct list_head acpi_wakeup_device_list; -extern spinlock_t acpi_device_lock; - /** * acpi_enable_wakeup_device_prep - prepare wakeup devices * @sleep_state: ACPI state @@ -29,7 +31,6 @@ void acpi_enable_wakeup_device_prep(u8 sleep_state) { struct list_head *node, *next; - spin_lock(&acpi_device_lock); list_for_each_safe(node, next, &acpi_wakeup_device_list) { struct acpi_device *dev = container_of(node, struct acpi_device, @@ -40,11 +41,8 @@ void acpi_enable_wakeup_device_prep(u8 sleep_state) (sleep_state > (u32) dev->wakeup.sleep_state)) continue; - spin_unlock(&acpi_device_lock); acpi_enable_wakeup_device_power(dev, sleep_state); - spin_lock(&acpi_device_lock); } - spin_unlock(&acpi_device_lock); } /** @@ -60,7 +58,6 @@ void acpi_enable_wakeup_device(u8 sleep_state) * Caution: this routine must be invoked when interrupt is disabled * Refer ACPI2.0: P212 */ - spin_lock(&acpi_device_lock); list_for_each_safe(node, next, &acpi_wakeup_device_list) { struct acpi_device *dev = container_of(node, struct acpi_device, wakeup_list); @@ -74,22 +71,17 @@ void acpi_enable_wakeup_device(u8 sleep_state) if ((!dev->wakeup.state.enabled && !dev->wakeup.flags.prepared) || sleep_state > (u32) dev->wakeup.sleep_state) { if (dev->wakeup.flags.run_wake) { - spin_unlock(&acpi_device_lock); /* set_gpe_type will disable GPE, leave it like that */ acpi_set_gpe_type(dev->wakeup.gpe_device, dev->wakeup.gpe_number, ACPI_GPE_TYPE_RUNTIME); - spin_lock(&acpi_device_lock); } continue; } - spin_unlock(&acpi_device_lock); if (!dev->wakeup.flags.run_wake) acpi_enable_gpe(dev->wakeup.gpe_device, dev->wakeup.gpe_number); - spin_lock(&acpi_device_lock); } - spin_unlock(&acpi_device_lock); } /** @@ -101,7 +93,6 @@ void acpi_disable_wakeup_device(u8 sleep_state) { struct list_head *node, *next; - spin_lock(&acpi_device_lock); list_for_each_safe(node, next, &acpi_wakeup_device_list) { struct acpi_device *dev = container_of(node, struct acpi_device, wakeup_list); @@ -112,19 +103,16 @@ void acpi_disable_wakeup_device(u8 sleep_state) if ((!dev->wakeup.state.enabled && !dev->wakeup.flags.prepared) || sleep_state > (u32) dev->wakeup.sleep_state) { if (dev->wakeup.flags.run_wake) { - spin_unlock(&acpi_device_lock); acpi_set_gpe_type(dev->wakeup.gpe_device, dev->wakeup.gpe_number, ACPI_GPE_TYPE_WAKE_RUN); /* Re-enable it, since set_gpe_type will disable it */ acpi_enable_gpe(dev->wakeup.gpe_device, dev->wakeup.gpe_number); - spin_lock(&acpi_device_lock); } continue; } - spin_unlock(&acpi_device_lock); acpi_disable_wakeup_device_power(dev); /* Never disable run-wake GPE */ if (!dev->wakeup.flags.run_wake) { @@ -133,16 +121,14 @@ void acpi_disable_wakeup_device(u8 sleep_state) acpi_clear_gpe(dev->wakeup.gpe_device, dev->wakeup.gpe_number, ACPI_NOT_ISR); } - spin_lock(&acpi_device_lock); } - spin_unlock(&acpi_device_lock); } int __init acpi_wakeup_device_init(void) { struct list_head *node, *next; - spin_lock(&acpi_device_lock); + mutex_lock(&acpi_device_lock); list_for_each_safe(node, next, &acpi_wakeup_device_list) { struct acpi_device *dev = container_of(node, struct acpi_device, @@ -150,15 +136,13 @@ int __init acpi_wakeup_device_init(void) /* In case user doesn't load button driver */ if (!dev->wakeup.flags.run_wake || dev->wakeup.state.enabled) continue; - spin_unlock(&acpi_device_lock); acpi_set_gpe_type(dev->wakeup.gpe_device, dev->wakeup.gpe_number, ACPI_GPE_TYPE_WAKE_RUN); acpi_enable_gpe(dev->wakeup.gpe_device, dev->wakeup.gpe_number); dev->wakeup.state.enabled = 1; - spin_lock(&acpi_device_lock); } - spin_unlock(&acpi_device_lock); + mutex_unlock(&acpi_device_lock); return 0; } |