diff options
author | Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com> | 2006-12-06 23:38:11 -0500 |
---|---|---|
committer | Linus Torvalds <torvalds@woody.osdl.org> | 2006-12-07 11:39:38 -0500 |
commit | b4c6c34a530b4d1c626f4ac0a884e0a9b849378c (patch) | |
tree | 5705a4621b6668bced1969396465800256d76c76 /arch/ia64/kernel/kprobes.c | |
parent | c15bb296403f1ce448384d58742e0dc04f49d664 (diff) |
[PATCH] kprobes: enable booster on the preemptible kernel
When we are unregistering a kprobe-booster, we can't release its
instruction buffer immediately on the preemptive kernel, because some
processes might be preempted on the buffer. The freeze_processes() and
thaw_processes() functions can clean most of processes up from the buffer.
There are still some non-frozen threads who have the PF_NOFREEZE flag. If
those threads are sleeping (not preempted) at the known place outside the
buffer, we can ensure safety of freeing.
However, the processing of this check routine takes a long time. So, this
patch introduces the garbage collection mechanism of insn_slot. It also
introduces the "dirty" flag to free_insn_slot because of efficiency.
The "clean" instruction slots (dirty flag is cleared) are released
immediately. But the "dirty" slots which are used by boosted kprobes, are
marked as garbages. collect_garbage_slots() will be invoked to release
"dirty" slots if there are more than INSNS_PER_PAGE garbage slots or if
there are no unused slots.
Cc: "Keshavamurthy, Anil S" <anil.s.keshavamurthy@intel.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: "bibo,mao" <bibo.mao@intel.com>
Cc: Prasanna S Panchamukhi <prasanna@in.ibm.com>
Cc: Yumiko Sugita <yumiko.sugita.yf@hitachi.com>
Cc: Satoshi Oshima <soshima@redhat.com>
Cc: Hideo Aoki <haoki@redhat.com>
Signed-off-by: Masami Hiramatsu <masami.hiramatsu.pt@hitachi.com>
Acked-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/ia64/kernel/kprobes.c')
-rw-r--r-- | arch/ia64/kernel/kprobes.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/ia64/kernel/kprobes.c b/arch/ia64/kernel/kprobes.c index 51217d63285e..4d592ee9300b 100644 --- a/arch/ia64/kernel/kprobes.c +++ b/arch/ia64/kernel/kprobes.c | |||
@@ -481,7 +481,7 @@ void __kprobes arch_disarm_kprobe(struct kprobe *p) | |||
481 | void __kprobes arch_remove_kprobe(struct kprobe *p) | 481 | void __kprobes arch_remove_kprobe(struct kprobe *p) |
482 | { | 482 | { |
483 | mutex_lock(&kprobe_mutex); | 483 | mutex_lock(&kprobe_mutex); |
484 | free_insn_slot(p->ainsn.insn); | 484 | free_insn_slot(p->ainsn.insn, 0); |
485 | mutex_unlock(&kprobe_mutex); | 485 | mutex_unlock(&kprobe_mutex); |
486 | } | 486 | } |
487 | /* | 487 | /* |