diff options
Diffstat (limited to 'drivers/acpi/osl.c')
| -rw-r--r-- | drivers/acpi/osl.c | 89 |
1 files changed, 21 insertions, 68 deletions
diff --git a/drivers/acpi/osl.c b/drivers/acpi/osl.c index a697fb6..a498a6c 100644 --- a/drivers/acpi/osl.c +++ b/drivers/acpi/osl.c @@ -4,6 +4,8 @@ * Copyright (C) 2000 Andrew Henroid * Copyright (C) 2001, 2002 Andy Grover <andrew.grover@intel.com> * Copyright (C) 2001, 2002 Paul Diefenbaugh <paul.s.diefenbaugh@intel.com> + * Copyright (c) 2008 Intel Corporation + * Author: Matthew Wilcox <willy@linux.intel.com> * * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * @@ -37,15 +39,18 @@ #include <linux/workqueue.h> #include <linux/nmi.h> #include <linux/acpi.h> -#include <acpi/acpi.h> -#include <asm/io.h> -#include <acpi/acpi_bus.h> -#include <acpi/processor.h> -#include <asm/uaccess.h> - #include <linux/efi.h> #include <linux/ioport.h> #include <linux/list.h> +#include <linux/jiffies.h> +#include <linux/semaphore.h> + +#include <asm/io.h> +#include <asm/uaccess.h> + +#include <acpi/acpi.h> +#include <acpi/acpi_bus.h> +#include <acpi/processor.h> #define _COMPONENT ACPI_OS_SERVICES ACPI_MODULE_NAME("osl"); @@ -764,7 +769,6 @@ acpi_os_create_semaphore(u32 max_units, u32 initial_units, acpi_handle * handle) { struct semaphore *sem = NULL; - sem = acpi_os_allocate(sizeof(struct semaphore)); if (!sem) return AE_NO_MEMORY; @@ -791,12 +795,12 @@ acpi_status acpi_os_delete_semaphore(acpi_handle handle) { struct semaphore *sem = (struct semaphore *)handle; - if (!sem) return AE_BAD_PARAMETER; ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Deleting semaphore[%p].\n", handle)); + BUG_ON(!list_empty(&sem->wait_list)); kfree(sem); sem = NULL; @@ -804,21 +808,15 @@ acpi_status acpi_os_delete_semaphore(acpi_handle handle) } /* - * TODO: The kernel doesn't have a 'down_timeout' function -- had to - * improvise. The process is to sleep for one scheduler quantum - * until the semaphore becomes available. Downside is that this - * may result in starvation for timeout-based waits when there's - * lots of semaphore activity. - * * TODO: Support for units > 1? */ acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout) { acpi_status status = AE_OK; struct semaphore *sem = (struct semaphore *)handle; + long jiffies; int ret = 0; - if (!sem || (units < 1)) return AE_BAD_PARAMETER; @@ -828,58 +826,14 @@ acpi_status acpi_os_wait_semaphore(acpi_handle handle, u32 units, u16 timeout) ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, "Waiting for semaphore[%p|%d|%d]\n", handle, units, timeout)); - /* - * This can be called during resume with interrupts off. - * Like boot-time, we should be single threaded and will - * always get the lock if we try -- timeout or not. - * If this doesn't succeed, then we will oops courtesy of - * might_sleep() in down(). - */ - if (!down_trylock(sem)) - return AE_OK; - - switch (timeout) { - /* - * No Wait: - * -------- - * A zero timeout value indicates that we shouldn't wait - just - * acquire the semaphore if available otherwise return AE_TIME - * (a.k.a. 'would block'). - */ - case 0: - if (down_trylock(sem)) - status = AE_TIME; - break; - - /* - * Wait Indefinitely: - * ------------------ - */ - case ACPI_WAIT_FOREVER: - down(sem); - break; - - /* - * Wait w/ Timeout: - * ---------------- - */ - default: - // TODO: A better timeout algorithm? - { - int i = 0; - static const int quantum_ms = 1000 / HZ; - - ret = down_trylock(sem); - for (i = timeout; (i > 0 && ret != 0); i -= quantum_ms) { - schedule_timeout_interruptible(1); - ret = down_trylock(sem); - } - - if (ret != 0) - status = AE_TIME; - } - break; - } + if (timeout == ACPI_WAIT_FOREVER) + jiffies = MAX_SCHEDULE_TIMEOUT; + else + jiffies = msecs_to_jiffies(timeout); + + ret = down_timeout(sem, jiffies); + if (ret) + status = AE_TIME; if (ACPI_FAILURE(status)) { ACPI_DEBUG_PRINT((ACPI_DB_MUTEX, @@ -902,7 +856,6 @@ acpi_status acpi_os_signal_semaphore(acpi_handle handle, u32 units) { struct semaphore *sem = (struct semaphore *)handle; - if (!sem || (units < 1)) return AE_BAD_PARAMETER; |