binder: remove global binder lock
authorTodd Kjos <tkjos@android.com>
Thu, 29 Jun 2017 19:02:11 +0000 (12:02 -0700)
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>
Mon, 17 Jul 2017 12:49:14 +0000 (14:49 +0200)
Remove global mutex and rely on fine-grained locking

Signed-off-by: Todd Kjos <tkjos@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
drivers/android/binder.c

index 1e50b03..c8e9d5d 100644 (file)
@@ -80,8 +80,6 @@
 #include "binder_alloc.h"
 #include "binder_trace.h"
 
-static DEFINE_MUTEX(binder_main_lock);
-
 static HLIST_HEAD(binder_deferred_list);
 static DEFINE_MUTEX(binder_deferred_lock);
 
@@ -924,19 +922,6 @@ static long task_close_fd(struct binder_proc *proc, unsigned int fd)
        return retval;
 }
 
-static inline void binder_lock(const char *tag)
-{
-       trace_binder_lock(tag);
-       mutex_lock(&binder_main_lock);
-       trace_binder_locked(tag);
-}
-
-static inline void binder_unlock(const char *tag)
-{
-       trace_binder_unlock(tag);
-       mutex_unlock(&binder_main_lock);
-}
-
 static void binder_set_nice(long nice)
 {
        long min_nice;
@@ -3557,8 +3542,6 @@ retry:
 
        thread->looper |= BINDER_LOOPER_STATE_WAITING;
 
-       binder_unlock(__func__);
-
        trace_binder_wait_for_work(wait_for_proc_work,
                                   !!thread->transaction_stack,
                                   !binder_worklist_empty(proc, &thread->todo));
@@ -3584,8 +3567,6 @@ retry:
                        ret = wait_event_freezable(thread->wait, binder_has_thread_work(thread));
        }
 
-       binder_lock(__func__);
-
        binder_inner_proc_lock(proc);
        if (wait_for_proc_work)
                proc->ready_threads--;
@@ -4101,8 +4082,6 @@ static unsigned int binder_poll(struct file *filp,
        struct binder_thread *thread = NULL;
        int wait_for_proc_work;
 
-       binder_lock(__func__);
-
        thread = binder_get_thread(proc);
 
        binder_inner_proc_lock(thread->proc);
@@ -4110,8 +4089,6 @@ static unsigned int binder_poll(struct file *filp,
                binder_worklist_empty_ilocked(&thread->todo);
        binder_inner_proc_unlock(thread->proc);
 
-       binder_unlock(__func__);
-
        if (wait_for_proc_work) {
                if (binder_has_proc_work(proc, thread))
                        return POLLIN;
@@ -4256,7 +4233,6 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
        if (ret)
                goto err_unlocked;
 
-       binder_lock(__func__);
        thread = binder_get_thread(proc);
        if (thread == NULL) {
                ret = -ENOMEM;
@@ -4315,7 +4291,6 @@ static long binder_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
 err:
        if (thread)
                thread->looper_need_return = false;
-       binder_unlock(__func__);
        wait_event_interruptible(binder_user_error_wait, binder_stop_on_user_error < 2);
        if (ret && ret != -ERESTARTSYS)
                pr_info("%d:%d ioctl %x %lx returned %d\n", proc->pid, current->pid, cmd, arg, ret);
@@ -4421,15 +4396,11 @@ static int binder_open(struct inode *nodp, struct file *filp)
        proc->context = &binder_dev->context;
        binder_alloc_init(&proc->alloc);
 
-       binder_lock(__func__);
-
        binder_stats_created(BINDER_STAT_PROC);
        proc->pid = current->group_leader->pid;
        INIT_LIST_HEAD(&proc->delivered_death);
        filp->private_data = proc;
 
-       binder_unlock(__func__);
-
        mutex_lock(&binder_procs_lock);
        hlist_add_head(&proc->proc_node, &binder_procs);
        mutex_unlock(&binder_procs_lock);
@@ -4655,7 +4626,6 @@ static void binder_deferred_func(struct work_struct *work)
        int defer;
 
        do {
-               binder_lock(__func__);
                mutex_lock(&binder_deferred_lock);
                if (!hlist_empty(&binder_deferred_list)) {
                        proc = hlist_entry(binder_deferred_list.first,
@@ -4682,7 +4652,6 @@ static void binder_deferred_func(struct work_struct *work)
                if (defer & BINDER_DEFERRED_RELEASE)
                        binder_deferred_release(proc); /* frees proc */
 
-               binder_unlock(__func__);
                if (files)
                        put_files_struct(files);
        } while (proc);
@@ -5097,8 +5066,6 @@ static int binder_state_show(struct seq_file *m, void *unused)
        struct binder_node *node;
        struct binder_node *last_node = NULL;
 
-       binder_lock(__func__);
-
        seq_puts(m, "binder state:\n");
 
        spin_lock(&binder_dead_nodes_lock);
@@ -5128,7 +5095,7 @@ static int binder_state_show(struct seq_file *m, void *unused)
        hlist_for_each_entry(proc, &binder_procs, proc_node)
                print_binder_proc(m, proc, 1);
        mutex_unlock(&binder_procs_lock);
-       binder_unlock(__func__);
+
        return 0;
 }
 
@@ -5136,8 +5103,6 @@ static int binder_stats_show(struct seq_file *m, void *unused)
 {
        struct binder_proc *proc;
 
-       binder_lock(__func__);
-
        seq_puts(m, "binder stats:\n");
 
        print_binder_stats(m, "", &binder_stats);
@@ -5146,7 +5111,7 @@ static int binder_stats_show(struct seq_file *m, void *unused)
        hlist_for_each_entry(proc, &binder_procs, proc_node)
                print_binder_proc_stats(m, proc);
        mutex_unlock(&binder_procs_lock);
-       binder_unlock(__func__);
+
        return 0;
 }
 
@@ -5154,14 +5119,12 @@ static int binder_transactions_show(struct seq_file *m, void *unused)
 {
        struct binder_proc *proc;
 
-       binder_lock(__func__);
-
        seq_puts(m, "binder transactions:\n");
        mutex_lock(&binder_procs_lock);
        hlist_for_each_entry(proc, &binder_procs, proc_node)
                print_binder_proc(m, proc, 0);
        mutex_unlock(&binder_procs_lock);
-       binder_unlock(__func__);
+
        return 0;
 }
 
@@ -5170,8 +5133,6 @@ static int binder_proc_show(struct seq_file *m, void *unused)
        struct binder_proc *itr;
        int pid = (unsigned long)m->private;
 
-       binder_lock(__func__);
-
        mutex_lock(&binder_procs_lock);
        hlist_for_each_entry(itr, &binder_procs, proc_node) {
                if (itr->pid == pid) {
@@ -5181,7 +5142,6 @@ static int binder_proc_show(struct seq_file *m, void *unused)
        }
        mutex_unlock(&binder_procs_lock);
 
-       binder_unlock(__func__);
        return 0;
 }