diff options
| author | Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com> | 2017-10-23 18:37:39 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-11-12 13:51:41 +0100 |
| commit | f72180cc93a2c64d4efe0129fa2396ad78be80e3 (patch) | |
| tree | 5bcb7d2e763cbd45bcedf15f99bf44ecdf0e1a7d /arch/powerpc | |
| parent | powerpc/kprobes: Disable preemption before invoking probe handler for optprobes (diff) | |
| download | linux-f72180cc93a2c64d4efe0129fa2396ad78be80e3.tar.xz linux-f72180cc93a2c64d4efe0129fa2396ad78be80e3.zip | |
powerpc/kprobes: Do not disable interrupts for optprobes and kprobes_on_ftrace
Per Documentation/kprobes.txt, we don't necessarily need to disable
interrupts before invoking the kprobe handlers. Masami submitted
similar changes for x86 via commit a19b2e3d783964 ("kprobes/x86: Remove
IRQ disabling from ftrace-based/optimized kprobes"). Do the same for
powerpc.
Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/kernel/kprobes-ftrace.c | 10 | ||||
| -rw-r--r-- | arch/powerpc/kernel/optprobes.c | 10 |
2 files changed, 2 insertions, 18 deletions
diff --git a/arch/powerpc/kernel/kprobes-ftrace.c b/arch/powerpc/kernel/kprobes-ftrace.c index 4b1f34f685b1..7a1f99f1b47f 100644 --- a/arch/powerpc/kernel/kprobes-ftrace.c +++ b/arch/powerpc/kernel/kprobes-ftrace.c @@ -75,11 +75,7 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, { struct kprobe *p; struct kprobe_ctlblk *kcb; - unsigned long flags; - /* Disable irq for emulating a breakpoint and avoiding preempt */ - local_irq_save(flags); - hard_irq_disable(); preempt_disable(); p = get_kprobe((kprobe_opcode_t *)nip); @@ -105,16 +101,14 @@ void kprobe_ftrace_handler(unsigned long nip, unsigned long parent_nip, else { /* * If pre_handler returns !0, it sets regs->nip and - * resets current kprobe. In this case, we still need - * to restore irq, but not preemption. + * resets current kprobe. In this case, we should not + * re-enable preemption. */ - local_irq_restore(flags); return; } } end: preempt_enable_no_resched(); - local_irq_restore(flags); } NOKPROBE_SYMBOL(kprobe_ftrace_handler); diff --git a/arch/powerpc/kernel/optprobes.c b/arch/powerpc/kernel/optprobes.c index 60ba7f1370a8..8237884ca389 100644 --- a/arch/powerpc/kernel/optprobes.c +++ b/arch/powerpc/kernel/optprobes.c @@ -115,14 +115,10 @@ static unsigned long can_optimize(struct kprobe *p) static void optimized_callback(struct optimized_kprobe *op, struct pt_regs *regs) { - unsigned long flags; - /* This is possible if op is under delayed unoptimizing */ if (kprobe_disabled(&op->kp)) return; - local_irq_save(flags); - hard_irq_disable(); preempt_disable(); if (kprobe_running()) { @@ -135,13 +131,7 @@ static void optimized_callback(struct optimized_kprobe *op, __this_cpu_write(current_kprobe, NULL); } - /* - * No need for an explicit __hard_irq_enable() here. - * local_irq_restore() will re-enable interrupts, - * if they were hard disabled. - */ preempt_enable_no_resched(); - local_irq_restore(flags); } NOKPROBE_SYMBOL(optimized_callback); |