diff options
Diffstat (limited to 'drivers/android/binder.c')
| -rw-r--r-- | drivers/android/binder.c | 196 |
1 files changed, 135 insertions, 61 deletions
diff --git a/drivers/android/binder.c b/drivers/android/binder.c index cc89d0d2b965..d21040c5d343 100644 --- a/drivers/android/binder.c +++ b/drivers/android/binder.c @@ -141,7 +141,7 @@ enum { }; static uint32_t binder_debug_mask = BINDER_DEBUG_USER_ERROR | BINDER_DEBUG_FAILED_TRANSACTION | BINDER_DEBUG_DEAD_TRANSACTION; -module_param_named(debug_mask, binder_debug_mask, uint, S_IWUSR | S_IRUGO); +module_param_named(debug_mask, binder_debug_mask, uint, 0644); static char *binder_devices_param = CONFIG_ANDROID_BINDER_DEVICES; module_param_named(devices, binder_devices_param, charp, 0444); @@ -160,7 +160,7 @@ static int binder_set_stop_on_user_error(const char *val, return ret; } module_param_call(stop_on_user_error, binder_set_stop_on_user_error, - param_get_int, &binder_stop_on_user_error, S_IWUSR | S_IRUGO); + param_get_int, &binder_stop_on_user_error, 0644); #define binder_debug(mask, x...) \ do { \ @@ -249,7 +249,7 @@ static struct binder_transaction_log_entry *binder_transaction_log_add( unsigned int cur = atomic_inc_return(&log->cur); if (cur >= ARRAY_SIZE(log->entry)) - log->full = 1; + log->full = true; e = &log->entry[cur % ARRAY_SIZE(log->entry)]; WRITE_ONCE(e->debug_id_done, 0); /* @@ -493,8 +493,6 @@ enum binder_deferred_state { * (protected by @inner_lock) * @todo: list of work for this process * (protected by @inner_lock) - * @wait: wait queue head to wait for proc work - * (invariant after initialized) * @stats: per-process binder statistics * (atomics, no lock needed) * @delivered_death: list of delivered death notification @@ -537,7 +535,6 @@ struct binder_proc { bool is_dead; struct list_head todo; - wait_queue_head_t wait; struct binder_stats stats; struct list_head delivered_death; int max_threads; @@ -579,6 +576,8 @@ enum { * (protected by @proc->inner_lock) * @todo: list of work to do for this thread * (protected by @proc->inner_lock) + * @process_todo: whether work in @todo should be processed + * (protected by @proc->inner_lock) * @return_error: transaction errors reported by this thread * (only accessed by this thread) * @reply_error: transaction errors reported by target thread @@ -604,6 +603,7 @@ struct binder_thread { bool looper_need_return; /* can be written by other thread */ struct binder_transaction *transaction_stack; struct list_head todo; + bool process_todo; struct binder_error return_error; struct binder_error reply_error; wait_queue_head_t wait; @@ -789,6 +789,16 @@ static bool binder_worklist_empty(struct binder_proc *proc, return ret; } +/** + * binder_enqueue_work_ilocked() - Add an item to the work list + * @work: struct binder_work to add to list + * @target_list: list to add work to + * + * Adds the work to the specified list. Asserts that work + * is not already on a list. + * + * Requires the proc->inner_lock to be held. + */ static void binder_enqueue_work_ilocked(struct binder_work *work, struct list_head *target_list) @@ -799,22 +809,56 @@ binder_enqueue_work_ilocked(struct binder_work *work, } /** - * binder_enqueue_work() - Add an item to the work list - * @proc: binder_proc associated with list + * binder_enqueue_deferred_thread_work_ilocked() - Add deferred thread work + * @thread: thread to queue work to * @work: struct binder_work to add to list - * @target_list: list to add work to * - * Adds the work to the specified list. Asserts that work - * is not already on a list. + * Adds the work to the todo list of the thread. Doesn't set the process_todo + * flag, which means that (if it wasn't already set) the thread will go to + * sleep without handling this work when it calls read. + * + * Requires the proc->inner_lock to be held. */ static void -binder_enqueue_work(struct binder_proc *proc, - struct binder_work *work, - struct list_head *target_list) +binder_enqueue_deferred_thread_work_ilocked(struct binder_thread *thread, + struct binder_work *work) { - binder_inner_proc_lock(proc); - binder_enqueue_work_ilocked(work, target_list); - binder_inner_proc_unlock(proc); + binder_enqueue_work_ilocked(work, &thread->todo); +} + +/** + * binder_enqueue_thread_work_ilocked() - Add an item to the thread work list + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread, and enables processing + * of the todo queue. + * + * Requires the proc->inner_lock to be held. + */ +static void +binder_enqueue_thread_work_ilocked(struct binder_thread *thread, + struct binder_work *work) +{ + binder_enqueue_work_ilocked(work, &thread->todo); + thread->process_todo = true; +} + +/** + * binder_enqueue_thread_work() - Add an item to the thread work list + * @thread: thread to queue work to + * @work: struct binder_work to add to list + * + * Adds the work to the todo list of the thread, and enables processing + * of the todo queue. + */ +static void +binder_enqueue_thread_work(struct binder_thread *thread, + struct binder_work *work) +{ + binder_inner_proc_lock(thread->proc); + binder_enqueue_thread_work_ilocked(thread, work); + binder_inner_proc_unlock(thread->proc); } static void @@ -940,7 +984,7 @@ err: static bool binder_has_work_ilocked(struct binder_thread *thread, bool do_proc_work) { - return !binder_worklist_empty_ilocked(&thread->todo) || + return thread->process_todo || thread->looper_need_return || (do_proc_work && !binder_worklist_empty_ilocked(&thread->proc->todo)); @@ -1228,6 +1272,17 @@ static int binder_inc_node_nilocked(struct binder_node *node, int strong, node->local_strong_refs++; if (!node->has_strong_ref && target_list) { binder_dequeue_work_ilocked(&node->work); + /* + * Note: this function is the only place where we queue + * directly to a thread->todo without using the + * corresponding binder_enqueue_thread_work() helper + * functions; in this case it's ok to not set the + * process_todo flag, since we know this node work will + * always be followed by other work that starts queue + * processing: in case of synchronous transactions, a + * BR_REPLY or BR_ERROR; in case of oneway + * transactions, a BR_TRANSACTION_COMPLETE. + */ binder_enqueue_work_ilocked(&node->work, target_list); } } else { @@ -1239,6 +1294,9 @@ static int binder_inc_node_nilocked(struct binder_node *node, int strong, node->debug_id); return -EINVAL; } + /* + * See comment above + */ binder_enqueue_work_ilocked(&node->work, target_list); } } @@ -1928,9 +1986,9 @@ static void binder_send_failed_reply(struct binder_transaction *t, binder_pop_transaction_ilocked(target_thread, t); if (target_thread->reply_error.cmd == BR_OK) { target_thread->reply_error.cmd = error_code; - binder_enqueue_work_ilocked( - &target_thread->reply_error.work, - &target_thread->todo); + binder_enqueue_thread_work_ilocked( + target_thread, + &target_thread->reply_error.work); wake_up_interruptible(&target_thread->wait); } else { WARN(1, "Unexpected reply error: %u\n", @@ -2569,20 +2627,18 @@ static bool binder_proc_transaction(struct binder_transaction *t, struct binder_proc *proc, struct binder_thread *thread) { - struct list_head *target_list = NULL; struct binder_node *node = t->buffer->target_node; bool oneway = !!(t->flags & TF_ONE_WAY); - bool wakeup = true; + bool pending_async = false; BUG_ON(!node); binder_node_lock(node); if (oneway) { BUG_ON(thread); if (node->has_async_transaction) { - target_list = &node->async_todo; - wakeup = false; + pending_async = true; } else { - node->has_async_transaction = 1; + node->has_async_transaction = true; } } @@ -2594,19 +2650,17 @@ static bool binder_proc_transaction(struct binder_transaction *t, return false; } - if (!thread && !target_list) + if (!thread && !pending_async) thread = binder_select_thread_ilocked(proc); if (thread) - target_list = &thread->todo; - else if (!target_list) - target_list = &proc->todo; + binder_enqueue_thread_work_ilocked(thread, &t->work); + else if (!pending_async) + binder_enqueue_work_ilocked(&t->work, &proc->todo); else - BUG_ON(target_list != &node->async_todo); + binder_enqueue_work_ilocked(&t->work, &node->async_todo); - binder_enqueue_work_ilocked(&t->work, target_list); - - if (wakeup) + if (!pending_async) binder_wakeup_thread_ilocked(proc, thread, !oneway /* sync */); binder_inner_proc_unlock(proc); @@ -3101,10 +3155,10 @@ static void binder_transaction(struct binder_proc *proc, } } tcomplete->type = BINDER_WORK_TRANSACTION_COMPLETE; - binder_enqueue_work(proc, tcomplete, &thread->todo); t->work.type = BINDER_WORK_TRANSACTION; if (reply) { + binder_enqueue_thread_work(thread, tcomplete); binder_inner_proc_lock(target_proc); if (target_thread->is_dead) { binder_inner_proc_unlock(target_proc); @@ -3112,13 +3166,21 @@ static void binder_transaction(struct binder_proc *proc, } BUG_ON(t->buffer->async_transaction != 0); binder_pop_transaction_ilocked(target_thread, in_reply_to); - binder_enqueue_work_ilocked(&t->work, &target_thread->todo); + binder_enqueue_thread_work_ilocked(target_thread, &t->work); binder_inner_proc_unlock(target_proc); wake_up_interruptible_sync(&target_thread->wait); binder_free_transaction(in_reply_to); } else if (!(t->flags & TF_ONE_WAY)) { BUG_ON(t->buffer->async_transaction != 0); binder_inner_proc_lock(proc); + /* + * Defer the TRANSACTION_COMPLETE, so we don't return to + * userspace immediately; this allows the target process to + * immediately start processing this transaction, reducing + * latency. We will then return the TRANSACTION_COMPLETE when + * the target replies (or there is an error). + */ + binder_enqueue_deferred_thread_work_ilocked(thread, tcomplete); t->need_reply = 1; t->from_parent = thread->transaction_stack; thread->transaction_stack = t; @@ -3132,6 +3194,7 @@ static void binder_transaction(struct binder_proc *proc, } else { BUG_ON(target_node == NULL); BUG_ON(t->buffer->async_transaction != 1); + binder_enqueue_thread_work(thread, tcomplete); if (!binder_proc_transaction(t, target_proc, NULL)) goto err_dead_proc_or_thread; } @@ -3210,15 +3273,11 @@ err_invalid_target_handle: BUG_ON(thread->return_error.cmd != BR_OK); if (in_reply_to) { thread->return_error.cmd = BR_TRANSACTION_COMPLETE; - binder_enqueue_work(thread->proc, - &thread->return_error.work, - &thread->todo); + binder_enqueue_thread_work(thread, &thread->return_error.work); binder_send_failed_reply(in_reply_to, return_error); } else { thread->return_error.cmd = return_error; - binder_enqueue_work(thread->proc, - &thread->return_error.work, - &thread->todo); + binder_enqueue_thread_work(thread, &thread->return_error.work); } } @@ -3424,7 +3483,7 @@ static int binder_thread_write(struct binder_proc *proc, w = binder_dequeue_work_head_ilocked( &buf_node->async_todo); if (!w) { - buf_node->has_async_transaction = 0; + buf_node->has_async_transaction = false; } else { binder_enqueue_work_ilocked( w, &proc->todo); @@ -3522,10 +3581,9 @@ static int binder_thread_write(struct binder_proc *proc, WARN_ON(thread->return_error.cmd != BR_OK); thread->return_error.cmd = BR_ERROR; - binder_enqueue_work( - thread->proc, - &thread->return_error.work, - &thread->todo); + binder_enqueue_thread_work( + thread, + &thread->return_error.work); binder_debug( BINDER_DEBUG_FAILED_TRANSACTION, "%d:%d BC_REQUEST_DEATH_NOTIFICATION failed\n", @@ -3605,9 +3663,9 @@ static int binder_thread_write(struct binder_proc *proc, if (thread->looper & (BINDER_LOOPER_STATE_REGISTERED | BINDER_LOOPER_STATE_ENTERED)) - binder_enqueue_work_ilocked( - &death->work, - &thread->todo); + binder_enqueue_thread_work_ilocked( + thread, + &death->work); else { binder_enqueue_work_ilocked( &death->work, @@ -3662,8 +3720,8 @@ static int binder_thread_write(struct binder_proc *proc, if (thread->looper & (BINDER_LOOPER_STATE_REGISTERED | BINDER_LOOPER_STATE_ENTERED)) - binder_enqueue_work_ilocked( - &death->work, &thread->todo); + binder_enqueue_thread_work_ilocked( + thread, &death->work); else { binder_enqueue_work_ilocked( &death->work, @@ -3837,6 +3895,8 @@ retry: break; } w = binder_dequeue_work_head_ilocked(list); + if (binder_worklist_empty_ilocked(&thread->todo)) + thread->process_todo = false; switch (w->type) { case BINDER_WORK_TRANSACTION: { @@ -4302,6 +4362,18 @@ static int binder_thread_release(struct binder_proc *proc, if (t) spin_lock(&t->lock); } + + /* + * If this thread used poll, make sure we remove the waitqueue + * from any epoll data structures holding it with POLLFREE. + * waitqueue_active() is safe to use here because we're holding + * the inner lock. + */ + if ((thread->looper & BINDER_LOOPER_STATE_POLL) && + waitqueue_active(&thread->wait)) { + wake_up_poll(&thread->wait, POLLHUP | POLLFREE); + } + binder_inner_proc_unlock(thread->proc); if (send_reply) @@ -4646,7 +4718,7 @@ static int binder_mmap(struct file *filp, struct vm_area_struct *vma) return 0; err_bad_arg: - pr_err("binder_mmap: %d %lx-%lx %s failed %d\n", + pr_err("%s: %d %lx-%lx %s failed %d\n", __func__, proc->pid, vma->vm_start, vma->vm_end, failure_string, ret); return ret; } @@ -4656,7 +4728,7 @@ static int binder_open(struct inode *nodp, struct file *filp) struct binder_proc *proc; struct binder_device *binder_dev; - binder_debug(BINDER_DEBUG_OPEN_CLOSE, "binder_open: %d:%d\n", + binder_debug(BINDER_DEBUG_OPEN_CLOSE, "%s: %d:%d\n", __func__, current->group_leader->pid, current->pid); proc = kzalloc(sizeof(*proc), GFP_KERNEL); @@ -4695,7 +4767,7 @@ static int binder_open(struct inode *nodp, struct file *filp) * anyway print all contexts that a given PID has, so this * is not a problem. */ - proc->debugfs_entry = debugfs_create_file(strbuf, S_IRUGO, + proc->debugfs_entry = debugfs_create_file(strbuf, 0444, binder_debugfs_dir_entry_proc, (void *)(unsigned long)proc->pid, &binder_proc_fops); @@ -5524,7 +5596,9 @@ static int __init binder_init(void) struct binder_device *device; struct hlist_node *tmp; - binder_alloc_shrinker_init(); + ret = binder_alloc_shrinker_init(); + if (ret) + return ret; atomic_set(&binder_transaction_log.cur, ~0U); atomic_set(&binder_transaction_log_failed.cur, ~0U); @@ -5536,27 +5610,27 @@ static int __init binder_init(void) if (binder_debugfs_dir_entry_root) { debugfs_create_file("state", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, NULL, &binder_state_fops); debugfs_create_file("stats", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, NULL, &binder_stats_fops); debugfs_create_file("transactions", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, NULL, &binder_transactions_fops); debugfs_create_file("transaction_log", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, &binder_transaction_log, &binder_transaction_log_fops); debugfs_create_file("failed_transaction_log", - S_IRUGO, + 0444, binder_debugfs_dir_entry_root, &binder_transaction_log_failed, &binder_transaction_log_fops); 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