printk: use rcuidle console tracepoint

[GitHub/mt8127/android_kernel_alcatel_ttab.git] / kernel / kprobes.c

diff --git a/kernel/kprobes.c b/kernel/kprobes.c
index e35be53f6613c4fd08c093b6865cd6f43e0b9a89..bddf3b201a480015e2b1b15c217c43ea6796fcd0 100644 (file)
--- a/kernel/kprobes.c
+++ b/kernel/kprobes.c
@@ -467,6 +467,7 @@ static struct kprobe *__kprobes get_optimized_kprobe(unsigned long addr)
 /* Optimization staging list, protected by kprobe_mutex */
 static LIST_HEAD(optimizing_list);
 static LIST_HEAD(unoptimizing_list);
+static LIST_HEAD(freeing_list);
 
 static void kprobe_optimizer(struct work_struct *work);
 static DECLARE_DELAYED_WORK(optimizing_work, kprobe_optimizer);
@@ -504,7 +505,7 @@ static __kprobes void do_optimize_kprobes(void)
  * Unoptimize (replace a jump with a breakpoint and remove the breakpoint
  * if need) kprobes listed on unoptimizing_list.
  */
-static __kprobes void do_unoptimize_kprobes(struct list_head *free_list)
+static __kprobes void do_unoptimize_kprobes(void)
 {
        struct optimized_kprobe *op, *tmp;
 
@@ -515,9 +516,9 @@ static __kprobes void do_unoptimize_kprobes(struct list_head *free_list)
        /* Ditto to do_optimize_kprobes */
        get_online_cpus();
        mutex_lock(&text_mutex);
-       arch_unoptimize_kprobes(&unoptimizing_list, free_list);
+       arch_unoptimize_kprobes(&unoptimizing_list, &freeing_list);
        /* Loop free_list for disarming */
-       list_for_each_entry_safe(op, tmp, free_list, list) {
+       list_for_each_entry_safe(op, tmp, &freeing_list, list) {
                /* Disarm probes if marked disabled */
                if (kprobe_disabled(&op->kp))
                        arch_disarm_kprobe(&op->kp);
@@ -536,11 +537,11 @@ static __kprobes void do_unoptimize_kprobes(struct list_head *free_list)
 }
 
 /* Reclaim all kprobes on the free_list */
-static __kprobes void do_free_cleaned_kprobes(struct list_head *free_list)
+static __kprobes void do_free_cleaned_kprobes(void)
 {
        struct optimized_kprobe *op, *tmp;
 
-       list_for_each_entry_safe(op, tmp, free_list, list) {
+       list_for_each_entry_safe(op, tmp, &freeing_list, list) {
                BUG_ON(!kprobe_unused(&op->kp));
                list_del_init(&op->list);
                free_aggr_kprobe(&op->kp);
@@ -556,8 +557,6 @@ static __kprobes void kick_kprobe_optimizer(void)
 /* Kprobe jump optimizer */
 static __kprobes void kprobe_optimizer(struct work_struct *work)
 {
-       LIST_HEAD(free_list);
-
        mutex_lock(&kprobe_mutex);
        /* Lock modules while optimizing kprobes */
        mutex_lock(&module_mutex);
@@ -566,7 +565,7 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
         * Step 1: Unoptimize kprobes and collect cleaned (unused and disarmed)
         * kprobes before waiting for quiesence period.
         */
-       do_unoptimize_kprobes(&free_list);
+       do_unoptimize_kprobes();
 
        /*
         * Step 2: Wait for quiesence period to ensure all running interrupts
@@ -581,7 +580,7 @@ static __kprobes void kprobe_optimizer(struct work_struct *work)
        do_optimize_kprobes();
 
        /* Step 4: Free cleaned kprobes after quiesence period */
-       do_free_cleaned_kprobes(&free_list);
+       do_free_cleaned_kprobes();
 
        mutex_unlock(&module_mutex);
        mutex_unlock(&kprobe_mutex);
@@ -723,8 +722,19 @@ static void __kprobes kill_optimized_kprobe(struct kprobe *p)
        if (!list_empty(&op->list))
                /* Dequeue from the (un)optimization queue */
                list_del_init(&op->list);
-
        op->kp.flags &= ~KPROBE_FLAG_OPTIMIZED;
+
+       if (kprobe_unused(p)) {
+               /* Enqueue if it is unused */
+               list_add(&op->list, &freeing_list);
+               /*
+                * Remove unused probes from the hash list. After waiting
+                * for synchronization, this probe is reclaimed.
+                * (reclaiming is done by do_free_cleaned_kprobes().)
+                */
+               hlist_del_rcu(&op->kp.hlist);
+       }
+
        /* Don't touch the code, because it is already freed. */
        arch_remove_optimized_kprobe(op);
 }
@@ -794,16 +804,16 @@ out:
 }
 
 #ifdef CONFIG_SYSCTL
-/* This should be called with kprobe_mutex locked */
 static void __kprobes optimize_all_kprobes(void)
 {
        struct hlist_head *head;
        struct kprobe *p;
        unsigned int i;
 
+       mutex_lock(&kprobe_mutex);
        /* If optimization is already allowed, just return */
        if (kprobes_allow_optimization)
-               return;
+               goto out;
 
        kprobes_allow_optimization = true;
        for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
@@ -813,18 +823,22 @@ static void __kprobes optimize_all_kprobes(void)
                                optimize_kprobe(p);
        }
        printk(KERN_INFO "Kprobes globally optimized\n");
+out:
+       mutex_unlock(&kprobe_mutex);
 }
 
-/* This should be called with kprobe_mutex locked */
 static void __kprobes unoptimize_all_kprobes(void)
 {
        struct hlist_head *head;
        struct kprobe *p;
        unsigned int i;
 
+       mutex_lock(&kprobe_mutex);
        /* If optimization is already prohibited, just return */
-       if (!kprobes_allow_optimization)
+       if (!kprobes_allow_optimization) {
+               mutex_unlock(&kprobe_mutex);
                return;
+       }
 
        kprobes_allow_optimization = false;
        for (i = 0; i < KPROBE_TABLE_SIZE; i++) {
@@ -834,11 +848,14 @@ static void __kprobes unoptimize_all_kprobes(void)
                                unoptimize_kprobe(p, false);
                }
        }
+       mutex_unlock(&kprobe_mutex);
+
        /* Wait for unoptimizing completion */
        wait_for_kprobe_optimizer();
        printk(KERN_INFO "Kprobes globally unoptimized\n");
 }
 
+static DEFINE_MUTEX(kprobe_sysctl_mutex);
 int sysctl_kprobes_optimization;
 int proc_kprobes_optimization_handler(struct ctl_table *table, int write,
                                      void __user *buffer, size_t *length,
@@ -846,7 +863,7 @@ int proc_kprobes_optimization_handler(struct ctl_table *table, int write,
 {
        int ret;
 
-       mutex_lock(&kprobe_mutex);
+       mutex_lock(&kprobe_sysctl_mutex);
        sysctl_kprobes_optimization = kprobes_allow_optimization ? 1 : 0;
        ret = proc_dointvec_minmax(table, write, buffer, length, ppos);
 
@@ -854,7 +871,7 @@ int proc_kprobes_optimization_handler(struct ctl_table *table, int write,
                optimize_all_kprobes();
        else
                unoptimize_all_kprobes();
-       mutex_unlock(&kprobe_mutex);
+       mutex_unlock(&kprobe_sysctl_mutex);
 
        return ret;
 }