mirror of
https://github.com/torvalds/linux
synced 2024-09-06 18:01:05 +00:00
timers: Update the documentation to reflect on the new timer_shutdown() API
In order to make sure that a timer is not re-armed after it is stopped before freeing, a new shutdown state is added to the timer code. The API timer_shutdown_sync() and timer_shutdown() must be called before the object that holds the timer can be freed. Update the documentation to reflect this new workflow. [ tglx: Updated to the new semantics and updated the zh_CN version ] Signed-off-by: Steven Rostedt (Google) <rostedt@goodmis.org> Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Tested-by: Guenter Roeck <linux@roeck-us.net> Reviewed-by: Jacob Keller <jacob.e.keller@intel.com> Reviewed-by: Anna-Maria Behnsen <anna-maria@linutronix.de> Link: https://lore.kernel.org/r/20221110064147.712934793@goodmis.org Link: https://lore.kernel.org/r/20221123201625.375284489@linutronix.de
This commit is contained in:
parent
f571faf6e4
commit
a31323bef2
|
@ -1858,7 +1858,7 @@ unloaded. After a given module has been unloaded, any attempt to call
|
|||
one of its functions results in a segmentation fault. The module-unload
|
||||
functions must therefore cancel any delayed calls to loadable-module
|
||||
functions, for example, any outstanding mod_timer() must be dealt
|
||||
with via timer_delete_sync() or similar.
|
||||
with via timer_shutdown_sync() or similar.
|
||||
|
||||
Unfortunately, there is no way to cancel an RCU callback; once you
|
||||
invoke call_rcu(), the callback function is eventually going to be
|
||||
|
|
|
@ -191,7 +191,7 @@ Here is a sample module which implements a basic per cpu counter using
|
|||
|
||||
static void __exit test_exit(void)
|
||||
{
|
||||
timer_delete_sync(&test_timer);
|
||||
timer_shutdown_sync(&test_timer);
|
||||
}
|
||||
|
||||
module_init(test_init);
|
||||
|
|
|
@ -1007,6 +1007,11 @@ calling add_timer() at the end of their timer function).
|
|||
Because this is a fairly common case which is prone to races, you should
|
||||
use timer_delete_sync() (``include/linux/timer.h``) to handle this case.
|
||||
|
||||
Before freeing a timer, timer_shutdown() or timer_shutdown_sync() should be
|
||||
called which will keep it from being rearmed. Any subsequent attempt to
|
||||
rearm the timer will be silently ignored by the core code.
|
||||
|
||||
|
||||
Locking Speed
|
||||
=============
|
||||
|
||||
|
|
|
@ -185,7 +185,7 @@ UP之间没有不同的行为,在你的架构的 ``local.h`` 中包括 ``asm-g
|
|||
|
||||
static void __exit test_exit(void)
|
||||
{
|
||||
timer_delete_sync(&test_timer);
|
||||
timer_shutdown_sync(&test_timer);
|
||||
}
|
||||
|
||||
module_init(test_init);
|
||||
|
|
Loading…
Reference in a new issue