[patch V3 11/20] rcuwait: Add @state argument to rcuwait_wait_event()
From: Thomas Gleixner <hidden>
Date: 2020-03-21 11:35:07
Also in:
linux-acpi, linux-pci, linux-pm, linux-usb, linux-wireless, linuxppc-dev, lkml, platform-driver-x86
From: Peter Zijlstra (Intel) <peterz@infradead.org> Extend rcuwait_wait_event() with a state variable so that it is not restricted to UNINTERRUPTIBLE waits. Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org> Signed-off-by: Thomas Gleixner <redacted> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Davidlohr Bueso <dave@stgolabs.net> --- include/linux/rcuwait.h | 12 ++++++++++-- kernel/locking/percpu-rwsem.c | 2 +- 2 files changed, 11 insertions(+), 3 deletions(-)
--- a/include/linux/rcuwait.h
+++ b/include/linux/rcuwait.h@@ -3,6 +3,7 @@ #define _LINUX_RCUWAIT_H_ #include <linux/rcupdate.h> +#include <linux/sched/signal.h> /* * rcuwait provides a way of blocking and waking up a single
@@ -30,23 +31,30 @@ extern void rcuwait_wake_up(struct rcuwa * The caller is responsible for locking around rcuwait_wait_event(), * such that writes to @task are properly serialized. */ -#define rcuwait_wait_event(w, condition) \ +#define rcuwait_wait_event(w, condition, state) \ ({ \ + int __ret = 0; \ rcu_assign_pointer((w)->task, current); \ for (;;) { \ /* \ * Implicit barrier (A) pairs with (B) in \ * rcuwait_wake_up(). \ */ \ - set_current_state(TASK_UNINTERRUPTIBLE); \ + set_current_state(state); \ if (condition) \ break; \ \ + if (signal_pending_state(state, current)) { \ + __ret = -EINTR; \ + break; \ + } \ + \ schedule(); \ } \ \ WRITE_ONCE((w)->task, NULL); \ __set_current_state(TASK_RUNNING); \ + __ret; \ }) #endif /* _LINUX_RCUWAIT_H_ */ --- a/kernel/locking/percpu-rwsem.c +++ b/kernel/locking/percpu-rwsem.c
@@ -162,7 +162,7 @@ void percpu_down_write(struct percpu_rw_ */ /* Wait for all now active readers to complete. */ - rcuwait_wait_event(&sem->writer, readers_active_check(sem)); + rcuwait_wait_event(&sem->writer, readers_active_check(sem), TASK_UNINTERRUPTIBLE); } EXPORT_SYMBOL_GPL(percpu_down_write);