*****************************************************************************/
/*
- * Copyright (C) 2000 - 2007, R. Byron Moore
+ * Copyright (C) 2000 - 2008, Intel Corp.
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
ACPI_EXPORT_SYMBOL(acpi_install_exception_handler)
#endif /* ACPI_FUTURE_USAGE */
-
/*******************************************************************************
*
* FUNCTION: acpi_install_fixed_event_handler
*
* DESCRIPTION: Acquire the ACPI Global Lock
*
+ * Note: Allows callers with the same thread ID to acquire the global lock
+ * multiple times. In other words, externally, the behavior of the global lock
+ * is identical to an AML mutex. On the first acquire, a new handle is
+ * returned. On any subsequent calls to acquire by the same thread, the same
+ * handle is returned.
+ *
******************************************************************************/
acpi_status acpi_acquire_global_lock(u16 timeout, u32 * handle)
{
return (AE_BAD_PARAMETER);
}
- status = acpi_ex_enter_interpreter();
- if (ACPI_FAILURE(status)) {
- return (status);
- }
+ /* Must lock interpreter to prevent race conditions */
- status = acpi_ev_acquire_global_lock(timeout);
- acpi_ex_exit_interpreter();
+ acpi_ex_enter_interpreter();
+
+ status = acpi_ex_acquire_mutex_object(timeout,
+ acpi_gbl_global_lock_mutex,
+ acpi_os_get_thread_id());
if (ACPI_SUCCESS(status)) {
- acpi_gbl_global_lock_handle++;
+
+ /* Return the global lock handle (updated in acpi_ev_acquire_global_lock) */
+
*handle = acpi_gbl_global_lock_handle;
}
+ acpi_ex_exit_interpreter();
return (status);
}
{
acpi_status status;
- if (handle != acpi_gbl_global_lock_handle) {
+ if (!handle || (handle != acpi_gbl_global_lock_handle)) {
return (AE_NOT_ACQUIRED);
}
- status = acpi_ev_release_global_lock();
+ status = acpi_ex_release_mutex_object(acpi_gbl_global_lock_mutex);
return (status);
}