Re: [rfc patch v4.4-rt2] sched: fix up preempt lazy forward port
From: Grygorii Strashko <grygorii.strashko@ti.com>
Date: 2016-01-25 17:14:25
Also in:
lkml
On 01/22/2016 10:40 PM, Sebastian Andrzej Siewior wrote:
quoted hunk ↗ jump to hunk
* Sebastian Andrzej Siewior | 2016-01-22 13:54:43 [+0100]:quoted
quoted
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
^^^^^^^^^^^^^^^^^ Should it be "fast_work_pending" in both cases?
quoted hunk ↗ jump to hunk
/* 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)
[...] -- regards, -grygorii