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-rw-r--r--include/linux/ring_buffer.h2
-rw-r--r--kernel/trace/ring_buffer.c5
-rw-r--r--kernel/trace/trace.c25
-rw-r--r--kernel/trace/trace.h4
4 files changed, 25 insertions, 11 deletions
diff --git a/include/linux/ring_buffer.h b/include/linux/ring_buffer.h
index d69cf637a15a..49a4d6f59108 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 fc4da2d97f9b..04202d9aa514 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 fd21e601a891..922657f30723 100644
--- a/kernel/trace/trace.c
+++ b/kernel/trace/trace.c
@@ -1091,13 +1091,13 @@ update_max_tr_single(struct trace_array *tr, struct task_struct *tsk, int cpu)
}
#endif /* CONFIG_TRACER_MAX_TRACE */
-static void default_wait_pipe(struct trace_iterator *iter)
+static int default_wait_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
@@ -4160,17 +4160,19 @@ tracing_poll_pipe(struct file *filp, poll_table *poll_table)
*
* Anyway, this is really very primitive wakeup.
*/
-void poll_wait_pipe(struct trace_iterator *iter)
+int poll_wait_pipe(struct trace_iterator *iter)
{
set_current_state(TASK_INTERRUPTIBLE);
/* sleep for 100 msecs, and try again. */
schedule_timeout(HZ / 10);
+ return 0;
}
/* Must be called with trace_types_lock mutex held. */
static int tracing_wait_pipe(struct file *filp)
{
struct trace_iterator *iter = filp->private_data;
+ int ret;
while (trace_empty(iter)) {
@@ -4180,10 +4182,13 @@ static int tracing_wait_pipe(struct file *filp)
mutex_unlock(&iter->mutex);
- iter->trace->wait_pipe(iter);
+ ret = iter->trace->wait_pipe(iter);
mutex_lock(&iter->mutex);
+ if (ret)
+ return ret;
+
if (signal_pending(current))
return -EINTR;
@@ -5111,8 +5116,12 @@ tracing_buffers_read(struct file *filp, char __user *ubuf,
goto out_unlock;
}
mutex_unlock(&trace_types_lock);
- iter->trace->wait_pipe(iter);
+ ret = iter->trace->wait_pipe(iter);
mutex_lock(&trace_types_lock);
+ if (ret) {
+ size = ret;
+ goto out_unlock;
+ }
if (signal_pending(current)) {
size = -EINTR;
goto out_unlock;
@@ -5324,8 +5333,10 @@ tracing_buffers_splice_read(struct file *file, loff_t *ppos,
goto out;
}
mutex_unlock(&trace_types_lock);
- iter->trace->wait_pipe(iter);
+ ret = iter->trace->wait_pipe(iter);
mutex_lock(&trace_types_lock);
+ if (ret)
+ goto out;
if (signal_pending(current)) {
ret = -EINTR;
goto out;
diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h
index 02b592f2d4b7..c8bd809cbd1c 100644
--- a/kernel/trace/trace.h
+++ b/kernel/trace/trace.h
@@ -336,7 +336,7 @@ struct tracer {
void (*stop)(struct trace_array *tr);
void (*open)(struct trace_iterator *iter);
void (*pipe_open)(struct trace_iterator *iter);
- void (*wait_pipe)(struct trace_iterator *iter);
+ int (*wait_pipe)(struct trace_iterator *iter);
void (*close)(struct trace_iterator *iter);
void (*pipe_close)(struct trace_iterator *iter);
ssize_t (*read)(struct trace_iterator *iter,
@@ -552,7 +552,7 @@ void trace_init_global_iter(struct trace_iterator *iter);
void tracing_iter_reset(struct trace_iterator *iter, int cpu);
-void poll_wait_pipe(struct trace_iterator *iter);
+int poll_wait_pipe(struct trace_iterator *iter);
void tracing_sched_switch_trace(struct trace_array *tr,
struct task_struct *prev,