The following commit has been merged into the irq/core branch of tip: Commit-ID: ca5f625118955fc544c3cb3dee7055d33ecadafb Gitweb: https://git.kernel.org/tip/ca5f625118955fc544c3cb3dee7055d33ecadafb Author: Thomas Gleixner <t...@linutronix.de> AuthorDate: Tue, 09 Mar 2021 09:42:06 +01:00 Committer: Thomas Gleixner <t...@linutronix.de> CommitterDate: Wed, 17 Mar 2021 16:33:52 +01:00
tasklets: Provide tasklet_disable_in_atomic() Replacing the spin wait loops in tasklet_unlock_wait() with wait_var_event() is not possible as a handful of tasklet_disable() invocations are happening in atomic context. All other invocations are in teardown paths which can sleep. Provide tasklet_disable_in_atomic() and tasklet_unlock_spin_wait() to convert the few atomic use cases over, which allows to change tasklet_disable() and tasklet_unlock_wait() in a later step. Signed-off-by: Thomas Gleixner <t...@linutronix.de> Acked-by: Peter Zijlstra (Intel) <pet...@infradead.org> Link: https://lore.kernel.org/r/20210309084241.563164...@linutronix.de --- include/linux/interrupt.h | 22 ++++++++++++++++++++++ 1 file changed, 22 insertions(+) diff --git a/include/linux/interrupt.h b/include/linux/interrupt.h index 0a4ce25..3c8a291 100644 --- a/include/linux/interrupt.h +++ b/include/linux/interrupt.h @@ -675,10 +675,21 @@ static inline void tasklet_unlock_wait(struct tasklet_struct *t) while (test_bit(TASKLET_STATE_RUN, &t->state)) cpu_relax(); } + +/* + * Do not use in new code. Waiting for tasklets from atomic contexts is + * error prone and should be avoided. + */ +static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) +{ + while (test_bit(TASKLET_STATE_RUN, &t->state)) + cpu_relax(); +} #else static inline int tasklet_trylock(struct tasklet_struct *t) { return 1; } static inline void tasklet_unlock(struct tasklet_struct *t) { } static inline void tasklet_unlock_wait(struct tasklet_struct *t) { } +static inline void tasklet_unlock_spin_wait(struct tasklet_struct *t) { } #endif extern void __tasklet_schedule(struct tasklet_struct *t); @@ -703,6 +714,17 @@ static inline void tasklet_disable_nosync(struct tasklet_struct *t) smp_mb__after_atomic(); } +/* + * Do not use in new code. Disabling tasklets from atomic contexts is + * error prone and should be avoided. + */ +static inline void tasklet_disable_in_atomic(struct tasklet_struct *t) +{ + tasklet_disable_nosync(t); + tasklet_unlock_spin_wait(t); + smp_mb(); +} + static inline void tasklet_disable(struct tasklet_struct *t) { tasklet_disable_nosync(t);
