ACPI: acpi_os_get_thread_id() returns current

Linux mutexes and the debug code that that reference
acpi_os_get_thread_id() are happy with 0.
But the AML mutexes in exmutex.c expect a unique non-zero
number for each thread - as they track this thread_id
to permit the mutex re-entrancy defined by the ACPI spec.

http://bugzilla.kernel.org/show_bug.cgi?id=6687

Signed-off-by: Len Brown <len.brown@intel.com>

5 files changed, 12 insertions, 11 deletions

diff --git a/drivers/acpi/executer/exmutex.c b/drivers/acpi/executer/exmutex.c
index d8ac2877cf05..3a39c2e8e104 100644
--- a/drivers/acpi/executer/exmutex.c
+++ b/drivers/acpi/executer/exmutex.c
@@ -267,9 +267,9 @@ acpi_ex_release_mutex(union acpi_operand_object *obj_desc,
 	    && (obj_desc->mutex.os_mutex != ACPI_GLOBAL_LOCK)) {
 		ACPI_ERROR((AE_INFO,
 			    "Thread %X cannot release Mutex [%4.4s] acquired by thread %X",
-			    walk_state->thread->thread_id,
+			    (u32) walk_state->thread->thread_id,
 			    acpi_ut_get_node_name(obj_desc->mutex.node),
-			    obj_desc->mutex.owner_thread->thread_id));
+			    (u32) obj_desc->mutex.owner_thread->thread_id));
 		return_ACPI_STATUS(AE_AML_NOT_OWNER);
 	}
 
diff --git a/drivers/acpi/utilities/utdebug.c b/drivers/acpi/utilities/utdebug.c
index 5ec1cfcc611d..bb1eaf9aa653 100644
--- a/drivers/acpi/utilities/utdebug.c
+++ b/drivers/acpi/utilities/utdebug.c
@@ -47,7 +47,7 @@
 ACPI_MODULE_NAME("utdebug")
 
 #ifdef ACPI_DEBUG_OUTPUT
-static u32 acpi_gbl_prev_thread_id = 0xFFFFFFFF;
+static acpi_thread_id acpi_gbl_prev_thread_id;
 static char *acpi_gbl_fn_entry_str = "----Entry";
 static char *acpi_gbl_fn_exit_str = "----Exit-";
 
@@ -181,7 +181,7 @@ acpi_ut_debug_print(u32 requested_debug_level,
 		if (ACPI_LV_THREADS & acpi_dbg_level) {
 			acpi_os_printf
 			    ("\n**** Context Switch from TID %X to TID %X ****\n\n",
-			     acpi_gbl_prev_thread_id, thread_id);
+			     (u32) acpi_gbl_prev_thread_id, (u32) thread_id);
 		}
 
 		acpi_gbl_prev_thread_id = thread_id;
diff --git a/drivers/acpi/utilities/utmutex.c b/drivers/acpi/utilities/utmutex.c
index dfc8f30ca892..c39062a047cd 100644
--- a/drivers/acpi/utilities/utmutex.c
+++ b/drivers/acpi/utilities/utmutex.c
@@ -244,14 +244,14 @@ acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
 
 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 			  "Thread %X attempting to acquire Mutex [%s]\n",
-			  this_thread_id, acpi_ut_get_mutex_name(mutex_id)));
+			  (u32) this_thread_id, acpi_ut_get_mutex_name(mutex_id)));
 
 	status = acpi_os_acquire_mutex(acpi_gbl_mutex_info[mutex_id].mutex,
 				       ACPI_WAIT_FOREVER);
 	if (ACPI_SUCCESS(status)) {
 		ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
 				  "Thread %X acquired Mutex [%s]\n",
-				  this_thread_id,
+				  (u32) this_thread_id,
 				  acpi_ut_get_mutex_name(mutex_id)));
 
 		acpi_gbl_mutex_info[mutex_id].use_count++;
@@ -259,7 +259,7 @@ acpi_status acpi_ut_acquire_mutex(acpi_mutex_handle mutex_id)
 	} else {
 		ACPI_EXCEPTION((AE_INFO, status,
 				"Thread %X could not acquire Mutex [%X]",
-				this_thread_id, mutex_id));
+				(u32) this_thread_id, mutex_id));
 	}
 
 	return (status);
@@ -285,7 +285,7 @@ acpi_status acpi_ut_release_mutex(acpi_mutex_handle mutex_id)
 
 	this_thread_id = acpi_os_get_thread_id();
 	ACPI_DEBUG_PRINT((ACPI_DB_MUTEX,
-			  "Thread %X releasing Mutex [%s]\n", this_thread_id,
+			  "Thread %X releasing Mutex [%s]\n", (u32) this_thread_id,
 			  acpi_ut_get_mutex_name(mutex_id)));
 
 	if (mutex_id > ACPI_MAX_MUTEX) {
diff --git a/include/acpi/aclocal.h b/include/acpi/aclocal.h
index 56b802486161..fbafee6e56d3 100644
--- a/include/acpi/aclocal.h
+++ b/include/acpi/aclocal.h
@@ -127,7 +127,7 @@ typedef u8 acpi_owner_id;
 
 /* This Thread ID means that the mutex is not in use (unlocked) */
 
-#define ACPI_MUTEX_NOT_ACQUIRED         (u32) -1
+#define ACPI_MUTEX_NOT_ACQUIRED         (acpi_thread_id) 0
 
 /* Table for the global mutexes */
 
diff --git a/include/acpi/platform/aclinux.h b/include/acpi/platform/aclinux.h
index 3f853cabbd41..1cb51bf96ece 100644
--- a/include/acpi/platform/aclinux.h
+++ b/include/acpi/platform/aclinux.h
@@ -59,6 +59,7 @@
 #include <asm/acpi.h>
 #include <linux/slab.h>
 #include <linux/spinlock_types.h>
+#include <asm/current.h>
 
 /* Host-dependent types and defines */
 
@@ -100,8 +101,8 @@
 
 #define acpi_cpu_flags unsigned long
 
-#define acpi_thread_id u32
+#define acpi_thread_id struct task_struct *
 
-static inline acpi_thread_id acpi_os_get_thread_id(void) { return 0; }
+static inline acpi_thread_id acpi_os_get_thread_id(void) { return current; }
 
 #endif				/* __ACLINUX_H__ */