[PATCH 03/10] ACPICA: Events: Remove acpi_ev_valid_gpe_event() due to current restriction.

Lv Zheng
2015-02-05T07:22:32Z

ACPICA commit 8823b44ff53859ab24ecfcfd3fba8cc56b17d223

Currently we rely on the logic that GPE blocks will never be deleted,
otherwise we can be broken by the race between acpi_ev_create_gpe_block(),
acpi_ev_delete_gpe_block() and acpi_ev_gpe_detect().
On the other hand, if we want to protect GPE block creation/deletion, we
need to use a different synchronization facility to protect the period
between acpi_ev_gpe_dispatch() and acpi_ev_asynch_enable_gpe(). Which leaves us
no choice but abandoning the ACPI_MTX_EVENTS used during this period.

This patch removes ACPI_MTX_EVENTS used during this period and the
acpi_ev_valid_gpe_event() to reflect current restriction. Lv Zheng.

Link: https://github.com/acpica/acpica/commit/8823b44f
Signed-off-by: Lv Zheng <lv.zheng@intel.com>
Acked-by: Rafael J. Wysocki <rjw@rjwysocki.net>
Signed-off-by: David E. Box <david.e.box@linux.intel.com>
Signed-off-by: Bob Moore <robert.moore@intel.com>
---
drivers/acpi/acpica/acevents.h | 2 --
drivers/acpi/acpica/evgpe.c | 62 ++++++++-------------------------------
drivers/acpi/acpica/evgpeutil.c | 51 ++------------------------------
3 files changed, 15 insertions(+), 100 deletions(-)

diff --git a/drivers/acpi/acpica/acevents.h b/drivers/acpi/acpica/acevents.h
index 7a7811a..38b94a1 100644
--- a/drivers/acpi/acpica/acevents.h
+++ b/drivers/acpi/acpica/acevents.h
@@ -143,8 +143,6 @@ acpi_ev_match_gpe_method(acpi_handle obj_handle,
acpi_status
acpi_ev_walk_gpe_list(acpi_gpe_callback gpe_walk_callback, void *context);

-u8 acpi_ev_valid_gpe_event(struct acpi_gpe_event_info *gpe_event_info);
-
acpi_status
acpi_ev_get_gpe_device(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
struct acpi_gpe_block_info *gpe_block, void *context);
diff --git a/drivers/acpi/acpica/evgpe.c b/drivers/acpi/acpica/evgpe.c
index b2e63e7..ddee967 100644
--- a/drivers/acpi/acpica/evgpe.c
+++ b/drivers/acpi/acpica/evgpe.c
@@ -474,51 +474,14 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
{
struct acpi_gpe_event_info *gpe_event_info = context;
acpi_status status;
- struct acpi_gpe_event_info *local_gpe_event_info;
struct acpi_evaluate_info *info;
struct acpi_gpe_notify_info *notify;

ACPI_FUNCTION_TRACE(ev_asynch_execute_gpe_method);

- /* Allocate a local GPE block */
-
- local_gpe_event_info =
- ACPI_ALLOCATE_ZEROED(sizeof(struct acpi_gpe_event_info));
- if (!local_gpe_event_info) {
- ACPI_EXCEPTION((AE_INFO, AE_NO_MEMORY, "while handling a GPE"));
- return_VOID;
- }
-
- status = acpi_ut_acquire_mutex(ACPI_MTX_EVENTS);
- if (ACPI_FAILURE(status)) {
- ACPI_FREE(local_gpe_event_info);
- return_VOID;
- }
-
- /* Must revalidate the gpe_number/gpe_block */
-
- if (!acpi_ev_valid_gpe_event(gpe_event_info)) {
- status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
- ACPI_FREE(local_gpe_event_info);
- return_VOID;
- }
-
- /*
- * Take a snapshot of the GPE info for this level - we copy the info to
- * prevent a race condition with remove_handler/remove_block.
- */
- ACPI_MEMCPY(local_gpe_event_info, gpe_event_info,
- sizeof(struct acpi_gpe_event_info));
-
- status = acpi_ut_release_mutex(ACPI_MTX_EVENTS);
- if (ACPI_FAILURE(status)) {
- ACPI_FREE(local_gpe_event_info);
- return_VOID;
- }
-
/* Do the correct dispatch - normal method or implicit notify */

- switch (local_gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
+ switch (gpe_event_info->flags & ACPI_GPE_DISPATCH_MASK) {
case ACPI_GPE_DISPATCH_NOTIFY:
/*
* Implicit notify.
@@ -531,7 +494,7 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
* June 2012: Expand implicit notify mechanism to support
* notifies on multiple device objects.
*/
- notify = local_gpe_event_info->dispatch.notify_list;
+ notify = gpe_event_info->dispatch.notify_list;
while (ACPI_SUCCESS(status) && notify) {
status =
acpi_ev_queue_notify_request(notify->device_node,
@@ -555,7 +518,7 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
* _Lxx/_Exx control method that corresponds to this GPE
*/
info->prefix_node =
- local_gpe_event_info->dispatch.method_node;
+ gpe_event_info->dispatch.method_node;
info->flags = ACPI_IGNORE_RETURN_VALUE;

status = acpi_ns_evaluate(info);
@@ -565,25 +528,27 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_execute_gpe_method(void *context)
if (ACPI_FAILURE(status)) {
ACPI_EXCEPTION((AE_INFO, status,
"while evaluating GPE method [%4.4s]",
- acpi_ut_get_node_name
- (local_gpe_event_info->dispatch.
- method_node)));
+ acpi_ut_get_node_name(gpe_event_info->
+ dispatch.
+ method_node)));
}
break;

default:

- return_VOID; /* Should never happen */
+ goto error_exit; /* Should never happen */
}

/* Defer enabling of GPE until all notify handlers are done */

status = acpi_os_execute(OSL_NOTIFY_HANDLER,
- acpi_ev_asynch_enable_gpe,
- local_gpe_event_info);
- if (ACPI_FAILURE(status)) {
- ACPI_FREE(local_gpe_event_info);
+ acpi_ev_asynch_enable_gpe, gpe_event_info);
+ if (ACPI_SUCCESS(status)) {
+ return_VOID;
}
+
+error_exit:
+ acpi_ev_asynch_enable_gpe(gpe_event_info);
return_VOID;
}

@@ -611,7 +576,6 @@ static void ACPI_SYSTEM_XFACE acpi_ev_asynch_enable_gpe(void *context)
(void)acpi_ev_finish_gpe(gpe_event_info);
acpi_os_release_lock(acpi_gbl_gpe_lock, flags);

- ACPI_FREE(gpe_event_info);
return;
}

diff --git a/drivers/acpi/acpica/evgpeutil.c b/drivers/acpi/acpica/evgpeutil.c
index 9e2b94c..3f1c5aa 100644
--- a/drivers/acpi/acpica/evgpeutil.c
+++ b/drivers/acpi/acpica/evgpeutil.c
@@ -108,53 +108,6 @@ unlock_and_exit:

/*******************************************************************************
*
- * FUNCTION: acpi_ev_valid_gpe_event
- *
- * PARAMETERS: gpe_event_info - Info for this GPE
- *
- * RETURN: TRUE if the gpe_event is valid
- *
- * DESCRIPTION: Validate a GPE event. DO NOT CALL FROM INTERRUPT LEVEL.
- * Should be called only when the GPE lists are semaphore locked
- * and not subject to change.
- *
- ******************************************************************************/
-
-u8 acpi_ev_valid_gpe_event(struct acpi_gpe_event_info *gpe_event_info)
-{
- struct acpi_gpe_xrupt_info *gpe_xrupt_block;
- struct acpi_gpe_block_info *gpe_block;
-
- ACPI_FUNCTION_ENTRY();
-
- /* No need for spin lock since we are not changing any list elements */
-
- /* Walk the GPE interrupt levels */
-
- gpe_xrupt_block = acpi_gbl_gpe_xrupt_list_head;
- while (gpe_xrupt_block) {
- gpe_block = gpe_xrupt_block->gpe_block_list_head;
-
- /* Walk the GPE blocks on this interrupt level */
-
- while (gpe_block) {
- if ((&gpe_block->event_info[0] <= gpe_event_info) &&
- (&gpe_block->event_info[gpe_block->gpe_count] >
- gpe_event_info)) {
- return (TRUE);
- }
-
- gpe_block = gpe_block->next;
- }
-
- gpe_xrupt_block = gpe_xrupt_block->next;
- }
-
- return (FALSE);
-}
-
-/*******************************************************************************
- *
* FUNCTION: acpi_ev_get_gpe_device
*
* PARAMETERS: GPE_WALK_CALLBACK
@@ -167,8 +120,8 @@ u8 acpi_ev_valid_gpe_event(struct acpi_gpe_event_info *gpe_event_info)
******************************************************************************/

acpi_status
-acpi_ev_get_gpe_device(struct acpi_gpe_xrupt_info * gpe_xrupt_info,
- struct acpi_gpe_block_info * gpe_block, void *context)
+acpi_ev_get_gpe_device(struct acpi_gpe_xrupt_info *gpe_xrupt_info,
+ struct acpi_gpe_block_info *gpe_block, void *context)
{
struct acpi_gpe_device_info *info = context;

--
1.7.10