[PATCH 2/4] acpi: add real mutex function calls

Daniel Walker
2008-08-26T19:00:41Z

Instead of re-using semaphores for the mutex operation, I've
added usage of the kernel mutex for the acpi os mutex
implementation.

Cc: linux-acpi@vger.kernel.org
Signed-off-by: Daniel Walker <dwalker@mvista.com>
---
drivers/acpi/osl.c | 93 +++++++++++++++++++++++++++++++++++++++++++++++
include/acpi/acpiosxf.h | 11 +-----
2 files changed, 95 insertions(+), 9 deletions(-)

diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c
index 235a138..e6f7337 100644
--- a/drivers/acpi/osl.c
+++ b/drivers/acpi/osl.c
@@ -871,6 +871,99 @@ acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units)
return AE_OK;
}

+acpi_status
+acpi_os_create_mutex(acpi_mutex *handle)
+{
+ struct mutex *mutex = NULL;
+
+ mutex = acpi_os_allocate(sizeof(struct mutex));
+ if (!mutex)
+ return AE_NO_MEMORY;
+ memset(mutex, 0, sizeof(struct mutex));
+
+ mutex_init(mutex);
+
+ *handle = (acpi_handle *) mutex;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Creating mutex[%p].\n",
+ *handle));
+
+ return AE_OK;
+}
+
+acpi_status acpi_os_delete_mutex(acpi_mutex handle)
+{
+ struct mutex *mutex = (struct mutex *)handle;
+
+ if (!mutex)
+ return AE_BAD_PARAMETER;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting mutex[%p].\n", handle));
+
+ BUG_ON(mutex_is_locked(mutex));
+ kfree(mutex);
+ mutex = NULL;
+
+ return AE_OK;
+}
+
+acpi_status acpi_os_acquire_mutex(acpi_mutex handle, u16 timeout)
+{
+ acpi_status status = AE_OK;
+ struct mutex *mutex = (struct mutex *)handle;
+ long jiffies;
+ int ret = 0;
+
+ if (!mutex)
+ return AE_BAD_PARAMETER;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for mutex[%p|%d]\n",
+ handle, timeout));
+
+ if (timeout == ACPI_DO_NOT_WAIT) {
+ if (mutex_trylock(mutex))
+ return status;
+ else
+ return -ETIME;
+ }
+
+ if (timeout == ACPI_WAIT_FOREVER)
+ jiffies = MAX_SCHEDULE_TIMEOUT;
+ else
+ jiffies = msecs_to_jiffies(timeout);
+
+ ret = mutex_lock_timeout(mutex, jiffies);
+ if (ret == -ETIME)
+ status = AE_TIME;
+
+ if (ACPI_FAILURE(status)) {
+ ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
+ "Failed to acquire mutex[%p|%d], %s",
+ handle, timeout,
+ acpi_format_exception(status)));
+ } else {
+ ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
+ "Acquired mutex[%p|%d]", handle,
+ timeout));
+ }
+
+ return status;
+}
+
+acpi_status acpi_os_release_mutex(acpi_mutex handle)
+{
+ struct mutex *mutex = (struct mutex *)handle;
+
+ if (!mutex)
+ return AE_BAD_PARAMETER;
+
+ ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Signaling mutex[%p]\n", handle));
+
+ mutex_unlock(mutex);
+
+ return AE_OK;
+}
+
#ifdef ACPI_FUTURE_USAGE
u32 acpi_os_get_line(char *buffer)
{
diff --git a/include/acpi/acpiosxf.h b/include/acpi/acpiosxf.h
index 3f93a6b..9032ec3 100644
--- a/include/acpi/acpiosxf.h
+++ b/include/acpi/acpiosxf.h
@@ -125,18 +125,11 @@ acpi_status acpi_os_signal_semaphore(acpi_semaphore handle, u32 units);
*/
acpi_status acpi_os_create_mutex(acpi_mutex * out_handle);

-void acpi_os_delete_mutex(acpi_mutex handle);
+acpi_status acpi_os_delete_mutex(acpi_mutex handle);

acpi_status acpi_os_acquire_mutex(acpi_mutex handle, u16 timeout);

-void acpi_os_release_mutex(acpi_mutex handle);
-
-/* Temporary macros for Mutex* interfaces, map to existing semaphore xfaces */
-
-#define acpi_os_create_mutex(out_handle) acpi_os_create_semaphore (1, 1, out_handle)
-#define acpi_os_delete_mutex(handle) (void) acpi_os_delete_semaphore (handle)
-#define acpi_os_acquire_mutex(handle,time) acpi_os_wait_semaphore (handle, 1, time)
-#define acpi_os_release_mutex(handle) (void) acpi_os_signal_semaphore (handle, 1)
+acpi_status acpi_os_release_mutex(acpi_mutex handle);

/*
* Memory allocation and mapping
--
1.5.5.1.32.gba7d2