Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]


Groups > linux.kernel > #1315265

Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port

From Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Newsgroups linux.kernel
Subject Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port
Date 2016-01-22 21:50 +0100
Message-ID <qTQOC-Mq-7@gated-at.bofh.it> (permalink)
References <qSdZ0-6VF-3@gated-at.bofh.it> <qSorp-5DG-23@gated-at.bofh.it> <qTIxI-3xw-19@gated-at.bofh.it> <qTJtM-497-7@gated-at.bofh.it>
Organization linux.* mail to news gateway

Show all headers | View raw


* Sebastian Andrzej Siewior | 2016-01-22 13:54:43 [+0100]:

>> Should _TIF_WORK_MASK also contain _TIF_NEED_RESCHED_LAZY?
>
>Yes, and arm64 lacks the same bits.

That would be this. If a compiler is reading here and knows how to
improve the following, please let me know :)

diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h
index 46cc07b5cae6..1f36a4eccc72 100644
--- a/arch/arm/include/asm/thread_info.h
+++ b/arch/arm/include/asm/thread_info.h
@@ -143,8 +143,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp __user *,
 #define TIF_SYSCALL_TRACE	4	/* syscall trace active */
 #define TIF_SYSCALL_AUDIT	5	/* syscall auditing active */
 #define TIF_SYSCALL_TRACEPOINT	6	/* syscall tracepoint instrumentation */
-#define TIF_SECCOMP		7	/* seccomp syscall filtering active */
-#define TIF_NEED_RESCHED_LAZY	8
+#define TIF_SECCOMP		8	/* seccomp syscall filtering active */
+#define TIF_NEED_RESCHED_LAZY	7
 
 #define TIF_NOHZ		12	/* in adaptive nohz mode */
 #define TIF_USING_IWMMXT	17
@@ -170,7 +170,8 @@ extern int vfp_restore_user_hwstate(struct user_vfp __user *,
  * Change these and you break ASM code in entry-common.S
  */
 #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
-				 _TIF_NOTIFY_RESUME | _TIF_UPROBE)
+				 _TIF_NOTIFY_RESUME | _TIF_UPROBE | \
+				 _TIF_NEED_RESCHED_LAZY)
 
 #endif /* __KERNEL__ */
 #endif /* __ASM_ARM_THREAD_INFO_H */
diff --git a/arch/arm/kernel/entry-common.S b/arch/arm/kernel/entry-common.S
index 30a7228eaceb..c3bd6cbfce4b 100644
--- a/arch/arm/kernel/entry-common.S
+++ b/arch/arm/kernel/entry-common.S
@@ -36,7 +36,9 @@
  UNWIND(.cantunwind	)
 	disable_irq_notrace			@ disable interrupts
 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+	tst	r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
+	bne	fast_work_pending
+	tst	r1, #_TIF_SECCOMP
 	bne	fast_work_pending
 
 	/* perform architecture specific actions before user return */
@@ -62,8 +64,11 @@ ENDPROC(ret_fast_syscall)
 	str	r0, [sp, #S_R0 + S_OFF]!	@ save returned r0
 	disable_irq_notrace			@ disable interrupts
 	ldr	r1, [tsk, #TI_FLAGS]		@ re-check for syscall tracing
-	tst	r1, #_TIF_SYSCALL_WORK | _TIF_WORK_MASK
+	tst	r1, #((_TIF_SYSCALL_WORK | _TIF_WORK_MASK) & ~_TIF_SECCOMP)
+	bne 	do_slower_path
+	tst	r1, #_TIF_SECCOMP
 	beq	no_work_pending
+do_slower_path:
  UNWIND(.fnend		)
 ENDPROC(ret_fast_syscall)
 
diff --git a/arch/arm64/include/asm/thread_info.h b/arch/arm64/include/asm/thread_info.h
index b229ef49a643..5f4e89fbc290 100644
--- a/arch/arm64/include/asm/thread_info.h
+++ b/arch/arm64/include/asm/thread_info.h
@@ -129,7 +129,8 @@ static inline struct thread_info *current_thread_info(void)
 #define _TIF_32BIT		(1 << TIF_32BIT)
 
 #define _TIF_WORK_MASK		(_TIF_NEED_RESCHED | _TIF_SIGPENDING | \
-				 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE)
+				 _TIF_NOTIFY_RESUME | _TIF_FOREIGN_FPSTATE | \
+				 _TIF_NEED_RESCHED_LAZY)
 
 #define _TIF_SYSCALL_WORK	(_TIF_SYSCALL_TRACE | _TIF_SYSCALL_AUDIT | \
 				 _TIF_SYSCALL_TRACEPOINT | _TIF_SECCOMP | \
-- 
2.7.0.rc3

Back to linux.kernel | Previous | NextPrevious in thread | Next in thread | Find similar | Unroll thread


Thread

[rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Mike Galbraith <umgwanakikbuti@gmail.com> - 2016-01-18 10:10 +0100
  Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2016-01-18 21:20 +0100
    Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Mike Galbraith <umgwanakikbuti@gmail.com> - 2016-01-19 03:40 +0100
      Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2016-01-21 14:00 +0100
        Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Grygorii Strashko <grygorii.strashko@ti.com> - 2016-01-22 13:30 +0100
          Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2016-01-22 14:20 +0100
            Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Grygorii Strashko <grygorii.strashko@ti.com> - 2016-01-22 14:40 +0100
              Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2016-01-22 15:20 +0100
                Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Grygorii Strashko <grygorii.strashko@ti.com> - 2016-01-22 16:10 +0100
                Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Grygorii Strashko <grygorii.strashko@ti.com> - 2016-01-22 19:30 +0100
    Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Mike Galbraith <umgwanakikbuti@gmail.com> - 2016-01-19 05:50 +0100
      Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Mike Galbraith <umgwanakikbuti@gmail.com> - 2016-01-19 06:20 +0100
    Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Grygorii Strashko <grygorii.strashko@ti.com> - 2016-01-22 13:00 +0100
      Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2016-01-22 14:00 +0100
        Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Sebastian Andrzej Siewior <bigeasy@linutronix.de> - 2016-01-22 21:50 +0100
          Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port Grygorii Strashko <grygorii.strashko@ti.com> - 2016-01-25 18:20 +0100

csiph-web