diff mbox series

[V2,06/15] rcuwait: Add @state argument to rcuwait_wait_event()

Message ID 20200318204408.010461877@linutronix.de
State New
Headers show
Series Lock ordering documentation and annotation for lockdep | expand

Commit Message

Thomas Gleixner March 18, 2020, 8:43 p.m. UTC 
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 <tglx@linutronix.de>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
---
 include/linux/rcuwait.h       |   12 ++++++++++--
 kernel/locking/percpu-rwsem.c |    2 +-
 2 files changed, 11 insertions(+), 3 deletions(-)

Comments

Davidlohr Bueso March 20, 2020, 5:36 a.m. UTC | #1 
On Wed, 18 Mar 2020, Thomas Gleixner wrote:

>--- 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>

So this is causing build to fail for me:

  CC      arch/x86/boot/compressed/cmdline.o
arch/x86/boot/compressed/cmdline.c:5:20: error: conflicting types for ‘set_fs’
 static inline void set_fs(unsigned long seg)
                    ^~~~~~
In file included from ./include/linux/uaccess.h:11:0,
                 from ./include/linux/sched/task.h:11,
                 from ./include/linux/sched/signal.h:9,
                 from ./include/linux/rcuwait.h:6,
                 from ./include/linux/percpu-rwsem.h:8,
                 from ./include/linux/fs.h:34,
                 from ./include/linux/proc_fs.h:9,
                 from ./include/acpi/acpi_bus.h:83,
                 from ./include/linux/acpi.h:32,
                 from arch/x86/boot/compressed/misc.h:28,
                 from arch/x86/boot/compressed/cmdline.c:2:
./arch/x86/include/asm/uaccess.h:29:20: note: previous definition of ‘set_fs’ was here
 static inline void set_fs(mm_segment_t fs)
                    ^~~~~~
make[2]: *** [scripts/Makefile.build:268: arch/x86/boot/compressed/cmdline.o] Error 1
make[1]: *** [arch/x86/boot/Makefile:113: arch/x86/boot/compressed/vmlinux] Error 2
make: *** [arch/x86/Makefile:285: bzImage] Error 2

Right now I'm not sure what the proper fix should be.

Thanks,
Davidlohr
Sebastian Andrzej Siewior March 20, 2020, 8:45 a.m. UTC | #2 
On 2020-03-19 22:36:57 [-0700], Davidlohr Bueso wrote:
> On Wed, 18 Mar 2020, Thomas Gleixner wrote:
> 
> Right now I'm not sure what the proper fix should be.

I though that v2 has it fixed with the previous commit (acpi: Remove
header dependency). The kbot just reported that everything is fine.
Let me look…

> Thanks,
> Davidlohr

Sebastian
Davidlohr Bueso March 20, 2020, 8:58 a.m. UTC | #3 
On Fri, 20 Mar 2020, Sebastian Andrzej Siewior wrote:

>I though that v2 has it fixed with the previous commit (acpi: Remove
>header dependency). The kbot just reported that everything is fine.
>Let me look???

Nah my bad, that build did not have the full series applied :)

Sorry for the noise.

Thanks,
Davidlohr
Sebastian Andrzej Siewior March 20, 2020, 9:48 a.m. UTC | #4 
The following mini-series removes linux/mm.h from the asm/uaccess.h of
the individual architecture. The series has been compile tested with the
defconfig and additionally for ia64 with the "special" allmodconfig
supplied by the bot. The regular allmod for the architectures does not
compile (even without the series).

Sebastian
diff mbox series

Patch

--- 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);