diff options
Diffstat (limited to 'fs/eventfd.c')
| -rw-r--r-- | fs/eventfd.c | 10 |
1 files changed, 7 insertions, 3 deletions
diff --git a/fs/eventfd.c b/fs/eventfd.c index 78e41c7c3d05..1d45cedeeb43 100644 --- a/fs/eventfd.c +++ b/fs/eventfd.c @@ -70,7 +70,8 @@ __u64 eventfd_signal(struct eventfd_ctx *ctx, __u64 n) * it returns true, the eventfd_signal() call should be deferred to a * safe context. */ - if (WARN_ON_ONCE(this_cpu_read(eventfd_wake_count))) + if (WARN_ON_ONCE(this_cpu_read(eventfd_wake_count) > + EFD_WAKE_COUNT_MAX)) return 0; spin_lock_irqsave(&ctx->wqh.lock, flags); @@ -181,11 +182,14 @@ static __poll_t eventfd_poll(struct file *file, poll_table *wait) return events; } -static void eventfd_ctx_do_read(struct eventfd_ctx *ctx, __u64 *cnt) +void eventfd_ctx_do_read(struct eventfd_ctx *ctx, __u64 *cnt) { - *cnt = (ctx->flags & EFD_SEMAPHORE) ? 1 : ctx->count; + lockdep_assert_held(&ctx->wqh.lock); + + *cnt = ((ctx->flags & EFD_SEMAPHORE) && ctx->count) ? 1 : ctx->count; ctx->count -= *cnt; } +EXPORT_SYMBOL_GPL(eventfd_ctx_do_read); /** * eventfd_ctx_remove_wait_queue - Read the current counter and removes wait queue. |