Messages in this thread Patch in this message |  | | | From | Masami Hiramatsu <> | | Subject | [PATCH -tip v3 2/5] [CLEANUP] kprobes: Remove redundant text_mutex lock in optimize | | Date | Wed, 19 May 2010 12:53:19 -0400 |
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Remove text_mutex locking in optimize_all_kprobes, because this function doesn't modify text. It simply queues probes on optimization list for kprobe_optimizer worker thread.
Changes in v2: - Update changelog. - Add comments for (un)optimize_all_kprobes. - Update kprobe_mutex comment.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com> Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Jim Keniston <jkenisto@us.ibm.com> Cc: Jason Baron <jbaron@redhat.com> Cc: Mathieu Desnoyers <mathieu.desnoyers@efficios.com> --- kernel/kprobes.c | 7 ++++--- 1 files changed, 4 insertions(+), 3 deletions(-) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index 282035f..f1351f2 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -73,7 +73,8 @@ static struct hlist_head kretprobe_inst_table[KPROBE_TABLE_SIZE]; /* NOTE: change this value only with kprobe_mutex held */ static bool kprobes_all_disarmed; -static DEFINE_MUTEX(kprobe_mutex); /* Protects kprobe_table */ +/* This protects kprobe_table and optimizing_list */ +static DEFINE_MUTEX(kprobe_mutex); static DEFINE_PER_CPU(struct kprobe *, kprobe_instance) = NULL; static struct { spinlock_t lock ____cacheline_aligned_in_smp; @@ -594,6 +595,7 @@ static __kprobes void try_to_optimize_kprobe(struct kprobe *p) } #ifdef CONFIG_SYSCTL +/* This should be called with kprobe_mutex locked */ static void __kprobes optimize_all_kprobes(void) { struct hlist_head *head; @@ -606,17 +608,16 @@ static void __kprobes optimize_all_kprobes(void) return; kprobes_allow_optimization = true; - mutex_lock(&text_mutex); for (i = 0; i < KPROBE_TABLE_SIZE; i++) { head = &kprobe_table[i]; hlist_for_each_entry_rcu(p, node, head, hlist) if (!kprobe_disabled(p)) optimize_kprobe(p); } - mutex_unlock(&text_mutex); printk(KERN_INFO "Kprobes globally optimized\n"); } +/* This should be called with kprobe_mutex locked */ static void __kprobes unoptimize_all_kprobes(void) { struct hlist_head *head;
-- Masami Hiramatsu e-mail: mhiramat@redhat.com
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