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authorAlexey Starikovskiy <alexey.y.starikovskiy@linux.intel.com>2007-03-07 00:57:30 -0500
committerLen Brown <len.brown@intel.com>2007-03-07 00:57:30 -0500
commit610a3d069665ba2b27e42c90129ce640c4d6e515 (patch)
treecd6b4bf8526fe8a7bae944a8e9b0fad335c60b08 /drivers/acpi/events
parent08e15e81a40e3241ce93b4a43886f3abda184aa6 (diff)
ACPICA: Fix ACPI Global Lock re-entrancy
patch "Delete recursive feature of ACPI Global Lock" broke re-entrancy of the Global Lock. The common routine to acquire GL is acpi_ev_acquire_global_lock, so check for re-entrancy _must_ be there, and not anywhere else. http://bugzilla.kernel.org/show_bug.cgi?id=8066#c9 Signed-off-by: Alexey Starikovskiy <alexey.y.starikovskiy@linux.intel.com> Signed-off-by: Len Brown <len.brown@intel.com>
Diffstat (limited to 'drivers/acpi/events')
-rw-r--r--drivers/acpi/events/evmisc.c25
1 files changed, 23 insertions, 2 deletions
diff --git a/drivers/acpi/events/evmisc.c b/drivers/acpi/events/evmisc.c
index d572700197f3..8dcade63b04b 100644
--- a/drivers/acpi/events/evmisc.c
+++ b/drivers/acpi/events/evmisc.c
@@ -423,6 +423,8 @@ static acpi_status acpi_ev_remove_global_lock_handler(void)
423 * the global lock appear as a standard mutex on the OS side. 423 * the global lock appear as a standard mutex on the OS side.
424 * 424 *
425 *****************************************************************************/ 425 *****************************************************************************/
426static acpi_thread_id acpi_ev_global_lock_thread_id;
427static int acpi_ev_global_lock_acquired;
426 428
427acpi_status acpi_ev_acquire_global_lock(u16 timeout) 429acpi_status acpi_ev_acquire_global_lock(u16 timeout)
428{ 430{
@@ -435,11 +437,24 @@ acpi_status acpi_ev_acquire_global_lock(u16 timeout)
435 * Only one thread can acquire the GL at a time, the global_lock_mutex 437 * Only one thread can acquire the GL at a time, the global_lock_mutex
436 * enforces this. This interface releases the interpreter if we must wait. 438 * enforces this. This interface releases the interpreter if we must wait.
437 */ 439 */
438 status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout); 440 status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, 0);
441 if (status == AE_TIME) {
442 if (acpi_ev_global_lock_thread_id == acpi_os_get_thread_id()) {
443 acpi_ev_global_lock_acquired++;
444 return AE_OK;
445 }
446 }
447
448 if (ACPI_FAILURE(status)) {
449 status = acpi_ex_system_wait_mutex(acpi_gbl_global_lock_mutex, timeout);
450 }
439 if (ACPI_FAILURE(status)) { 451 if (ACPI_FAILURE(status)) {
440 return_ACPI_STATUS(status); 452 return_ACPI_STATUS(status);
441 } 453 }
442 454
455 acpi_ev_global_lock_thread_id = acpi_os_get_thread_id();
456 acpi_ev_global_lock_acquired++;
457
443 /* 458 /*
444 * Make sure that a global lock actually exists. If not, just treat 459 * Make sure that a global lock actually exists. If not, just treat
445 * the lock as a standard mutex. 460 * the lock as a standard mutex.
@@ -506,6 +521,11 @@ acpi_status acpi_ev_release_global_lock(void)
506 return_ACPI_STATUS(AE_NOT_ACQUIRED); 521 return_ACPI_STATUS(AE_NOT_ACQUIRED);
507 } 522 }
508 523
524 acpi_ev_global_lock_acquired--;
525 if (acpi_ev_global_lock_acquired > 0) {
526 return AE_OK;
527 }
528
509 if (acpi_gbl_global_lock_present) { 529 if (acpi_gbl_global_lock_present) {
510 530
511 /* Allow any thread to release the lock */ 531 /* Allow any thread to release the lock */
@@ -529,7 +549,8 @@ acpi_status acpi_ev_release_global_lock(void)
529 acpi_gbl_global_lock_acquired = FALSE; 549 acpi_gbl_global_lock_acquired = FALSE;
530 550
531 /* Release the local GL mutex */ 551 /* Release the local GL mutex */
532 552 acpi_ev_global_lock_thread_id = 0;
553 acpi_ev_global_lock_acquired = 0;
533 acpi_os_release_mutex(acpi_gbl_global_lock_mutex); 554 acpi_os_release_mutex(acpi_gbl_global_lock_mutex);
534 return_ACPI_STATUS(status); 555 return_ACPI_STATUS(status);
535} 556}