diff options
author | Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | 2010-10-14 12:10:18 +0900 |
---|---|---|
committer | Ingo Molnar <mingo@elte.hu> | 2010-10-14 08:55:27 +0200 |
commit | 0f55a2f3d496133dd22f1e4e49fb7301da87c7bb (patch) | |
tree | 7196edf98b6e129fbb828460b683d9a0b3810960 | |
parent | 1efeb08d7dd32c0fbd4b784ea9303b53d345bfd0 (diff) |
kprobes: Update document about irq disabled state in kprobe handler
Update kprobes.txt about interrupts disabled state inside
kprobes handlers, because optimized probe/boosted kretprobe
run without disabling interrrupts on x86.
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: 2nddept-manager@sdl.hitachi.co.jp
LKML-Reference: <20101014031018.4100.64883.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
-rw-r--r-- | Documentation/kprobes.txt | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/Documentation/kprobes.txt b/Documentation/kprobes.txt index 1762b81fcdf2..741fe66d6eca 100644 --- a/Documentation/kprobes.txt +++ b/Documentation/kprobes.txt @@ -542,9 +542,11 @@ Kprobes does not use mutexes or allocate memory except during registration and unregistration. Probe handlers are run with preemption disabled. Depending on the -architecture, handlers may also run with interrupts disabled. In any -case, your handler should not yield the CPU (e.g., by attempting to -acquire a semaphore). +architecture and optimization state, handlers may also run with +interrupts disabled (e.g., kretprobe handlers and optimized kprobe +handlers run without interrupt disabled on x86/x86-64). In any case, +your handler should not yield the CPU (e.g., by attempting to acquire +a semaphore). Since a return probe is implemented by replacing the return address with the trampoline's address, stack backtraces and calls |