Add a counter to kick_kprobe_optimizer() to detect any additional register/unregister kprobes and postpone kprobe_optimizer() until a bunch of probes are registered. This might improve some long waiting unregistration process for bunch of kprobes. Signed-off-by: Masami Hiramatsu <mhiramat@xxxxxxxxxx> --- kernel/kprobes.c | 13 +++++++++++++ 1 file changed, 13 insertions(+) diff --git a/kernel/kprobes.c b/kernel/kprobes.c index a2c755e79be7..0dacdcecc90f 100644 --- a/kernel/kprobes.c +++ b/kernel/kprobes.c @@ -465,6 +465,7 @@ static struct kprobe *get_optimized_kprobe(unsigned long addr) static LIST_HEAD(optimizing_list); static LIST_HEAD(unoptimizing_list); static LIST_HEAD(freeing_list); +static int kprobe_optimizer_queue_update; static void kprobe_optimizer(struct work_struct *work); static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer); @@ -555,12 +556,22 @@ static void do_free_cleaned_kprobes(void) static void kick_kprobe_optimizer(void) { schedule_delayed_work(&optimizing_work, OPTIMIZE_DELAY); + kprobe_optimizer_queue_update++; } /* Kprobe jump optimizer */ static void kprobe_optimizer(struct work_struct *work) { mutex_lock(&kprobe_mutex); + + /* + * If new kprobe is queued in optimized/unoptimized list while + * OPTIMIZE_DELAY waiting period, wait again for a series of + * probes registration/unregistrations. + */ + if (kprobe_optimizer_queue_update > 1) + goto end; + cpus_read_lock(); mutex_lock(&text_mutex); /* Lock modules while optimizing kprobes */ @@ -593,6 +604,8 @@ static void kprobe_optimizer(struct work_struct *work) mutex_unlock(&text_mutex); cpus_read_unlock(); +end: + kprobe_optimizer_queue_update = 0; /* Step 5: Kick optimizer again if needed */ if (!list_empty(&optimizing_list) || !list_empty(&unoptimizing_list)) kick_kprobe_optimizer();