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From e9b2acffc0f367e77f0e3cedc628ed86a5486a9f Mon Sep 17 00:00:00 2001
From: Ingo Molnar <mingo@elte.hu>
Date: Fri, 3 Jul 2009 08:29:25 -0500
Subject: [PATCH] x86: kprobes: Fix missed preemptions
commit fc1193fdc2f917421949f07022bc92392ce86a7e in tip.
preempt_enable_no_resched() is only correct when we call schedule
right away. The use in kprobes is just increasing latencies for no
reason.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
---
arch/x86/kernel/kprobes.c | 10 +++++-----
1 files changed, 5 insertions(+), 5 deletions(-)
diff --git a/arch/x86/kernel/kprobes.c b/arch/x86/kernel/kprobes.c
index 1658efd..f8b1035 100644
--- a/arch/x86/kernel/kprobes.c
+++ b/arch/x86/kernel/kprobes.c
@@ -468,7 +468,7 @@ static void __kprobes setup_singlestep(struct kprobe *p, struct pt_regs *regs,
* stepping.
*/
regs->ip = (unsigned long)p->ainsn.insn;
- preempt_enable_no_resched();
+ preempt_enable();
return;
}
#endif
@@ -586,7 +586,7 @@ static int __kprobes kprobe_handler(struct pt_regs *regs)
}
} /* else: not a kprobe fault; let the kernel handle it */
- preempt_enable_no_resched();
+ preempt_enable();
return 0;
}
@@ -892,7 +892,7 @@ static int __kprobes post_kprobe_handler(struct pt_regs *regs)
}
reset_current_kprobe();
out:
- preempt_enable_no_resched();
+ preempt_enable();
/*
* if somebody else is singlestepping across a probe point, flags
@@ -926,7 +926,7 @@ int __kprobes kprobe_fault_handler(struct pt_regs *regs, int trapnr)
restore_previous_kprobe(kcb);
else
reset_current_kprobe();
- preempt_enable_no_resched();
+ preempt_enable();
break;
case KPROBE_HIT_ACTIVE:
case KPROBE_HIT_SSDONE:
@@ -1073,7 +1073,7 @@ int __kprobes longjmp_break_handler(struct kprobe *p, struct pt_regs *regs)
memcpy((kprobe_opcode_t *)(kcb->jprobe_saved_sp),
kcb->jprobes_stack,
MIN_STACK_SIZE(kcb->jprobe_saved_sp));
- preempt_enable_no_resched();
+ preempt_enable();
return 1;
}
return 0;
--
1.7.0.4
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