kprobes: Remove redundant text_mutex lock in optimize
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.
Signed-off-by: Masami Hiramatsu <mhiramat@redhat.com>
Cc: Ananth N Mavinakayanahalli <ananth@in.ibm.com>
Cc: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Cc: David S. Miller <davem@davemloft.net>
Cc: Namhyung Kim <namhyung@gmail.com>
Cc: Jason Baron <jbaron@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <20101025131801.19160.70939.stgit@ltc236.sdl.hitachi.co.jp>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index ec4210c..7c44133 100644
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -74,7 +74,8 @@
/* 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;
@@ -595,6 +596,7 @@
}
#ifdef CONFIG_SYSCTL
+/* This should be called with kprobe_mutex locked */
static void __kprobes optimize_all_kprobes(void)
{
struct hlist_head *head;
@@ -607,17 +609,16 @@
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;