diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h index d69cf637a15a3093863cd33f09929b87d73fd0a9..49a4d6f59108f957d4534190c161344981c48e46 100644 --- a/include/linux/ring_buffer.h +++ b/include/linux/ring_buffer.h @@ -97,7 +97,7 @@ __ring_buffer_alloc(unsigned long size, unsigned flags, struct lock_class_key *k __ring_buffer_alloc((size), (flags), &__key); \ }) -void ring_buffer_wait(struct ring_buffer *buffer, int cpu); +int ring_buffer_wait(struct ring_buffer *buffer, int cpu); int ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu, struct file *filp, poll_table *poll_table); diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index c634868c2921ca39837c3a36773c36fa4a3273d5..7c56c3d06943060d13ed611da638a09ccfa70ef4 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -543,7 +543,7 @@ static void rb_wake_up_waiters(struct irq_work *work) * as data is added to any of the @buffer's cpu buffers. Otherwise * it will wait for data to be added to a specific cpu buffer. */ -void ring_buffer_wait(struct ring_buffer *buffer, int cpu) +int ring_buffer_wait(struct ring_buffer *buffer, int cpu) { struct ring_buffer_per_cpu *cpu_buffer; DEFINE_WAIT(wait); @@ -557,6 +557,8 @@ void ring_buffer_wait(struct ring_buffer *buffer, int cpu) if (cpu == RING_BUFFER_ALL_CPUS) work = &buffer->irq_work; else { + if (!cpumask_test_cpu(cpu, buffer->cpumask)) + return -ENODEV; cpu_buffer = buffer->buffers[cpu]; work = &cpu_buffer->irq_work; } @@ -591,6 +593,7 @@ void ring_buffer_wait(struct ring_buffer *buffer, int cpu) schedule(); finish_wait(&work->waiters, &wait); + return 0; } /** diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 16f7038d1f4d7a245a3350cf9b647992072e94e0..56422f1decbaf2b3d00f74280632ef99b85db017 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -1085,13 +1085,13 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu) } #endif /* CONFIG_TRACER_MAX_TRACE */ -static void wait_on_pipe(struct trace_iterator *iter) +static int wait_on_pipe(struct trace_iterator *iter) { /* Iterators are static, they should be filled or empty */ if (trace_buffer_iter(iter, iter->cpu_file)) - return; + return 0; - ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); + return ring_buffer_wait(iter->trace_buffer->buffer, iter->cpu_file); } #ifdef CONFIG_FTRACE_STARTUP_TEST @@ -4378,6 +4378,7 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table) static int tracing_wait_pipe(struct file *filp) { struct trace_iterator *iter = filp->private_data; + int ret; while (trace_empty(iter)) { @@ -4399,10 +4400,13 @@ static int tracing_wait_pipe(struct file *filp) mutex_unlock(&iter->mutex); - wait_on_pipe(iter); + ret = wait_on_pipe(iter); mutex_lock(&iter->mutex); + if (ret) + return ret; + if (signal_pending(current)) return -EINTR; } @@ -5327,8 +5331,12 @@ tracing_buffers_read(struct file *filp, char __user *ubuf, goto out_unlock; } mutex_unlock(&trace_types_lock); - wait_on_pipe(iter); + ret = wait_on_pipe(iter); mutex_lock(&trace_types_lock); + if (ret) { + size = ret; + goto out_unlock; + } if (signal_pending(current)) { size = -EINTR; goto out_unlock; @@ -5538,8 +5546,10 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos, goto out; } mutex_unlock(&trace_types_lock); - wait_on_pipe(iter); + ret = wait_on_pipe(iter); mutex_lock(&trace_types_lock); + if (ret) + goto out; if (signal_pending(current)) { ret = -EINTR; goto out;