redonkable
/
alistair23-linux
1
0
Fork 0
Code Releases Activity

thinkpad-acpi: kill hotkey_thread_mutex 

hotkey_kthread() does try_to_freeze() under hotkey_thread_mutex.

We can simply kill this mutex, hotkey_poll_stop_sync() does not need to
serialize with hotkey_kthread().  When kthread_stop() returns the thread
is already dead, it called do_exit()->complete_vfork_done().

Reported-by: Artem Savkov <artem.savkov@gmail.com>
Reported-by: Maciej Rutecki <maciej.rutecki@gmail.com>
Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-by: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: Matthew Garrett <matthew.garrett@nebula.com>
Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
Reviewed-by: Mandeep Singh Baines <msb@chromium.org>
Cc: Aaron Lu <aaron.lu@intel.com>
Cc: Tejun Heo <tj@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
hifive-unleashed-5.1
Oleg Nesterov 2013-04-17 15:58:23 -07:00 committed by Linus Torvalds
parent fca83168aa
commit 355f1ecbcc
1 changed files with 0 additions and 10 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

10
drivers/platform/x86/thinkpad_acpi.c
View File

@ -1964,9 +1964,6 @@ struct tp_nvram_state {
/* kthread for the hotkey poller */
static struct task_struct *tpacpi_hotkey_task;
/* Acquired while the poller kthread is running, use to sync start/stop */
static struct mutex hotkey_thread_mutex;
/*
* Acquire mutex to write poller control variables as an
* atomic block.
@ -2462,8 +2459,6 @@ static int hotkey_kthread(void *data)
unsigned int poll_freq;
bool was_frozen;
mutex_lock(&hotkey_thread_mutex);
if (tpacpi_lifecycle == TPACPI_LIFE_EXITING)
goto exit;
@ -2523,7 +2518,6 @@ static int hotkey_kthread(void *data)
}
exit:
mutex_unlock(&hotkey_thread_mutex);
return 0;
}
@ -2533,9 +2527,6 @@ static void hotkey_poll_stop_sync(void)
if (tpacpi_hotkey_task) {
kthread_stop(tpacpi_hotkey_task);
tpacpi_hotkey_task = NULL;
mutex_lock(&hotkey_thread_mutex);
/* at this point, the thread did exit */
mutex_unlock(&hotkey_thread_mutex);
}
}
@ -3234,7 +3225,6 @@ static int __init hotkey_init(struct ibm_init_struct *iibm)
mutex_init(&hotkey_mutex);
#ifdef CONFIG_THINKPAD_ACPI_HOTKEY_POLL
mutex_init(&hotkey_thread_mutex);
mutex_init(&hotkey_thread_data_mutex);
#endif