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Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c63
1 files changed, 37 insertions, 26 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index e444ff88f0a..ff7027199a9 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -36,11 +36,11 @@ int ring_buffer_print_entry_header(struct trace_seq *s)
{
int ret;
- ret = trace_seq_printf(s, "# compressed entry header\n");
- ret = trace_seq_printf(s, "\ttype_len : 5 bits\n");
- ret = trace_seq_printf(s, "\ttime_delta : 27 bits\n");
- ret = trace_seq_printf(s, "\tarray : 32 bits\n");
- ret = trace_seq_printf(s, "\n");
+ ret = trace_seq_puts(s, "# compressed entry header\n");
+ ret = trace_seq_puts(s, "\ttype_len : 5 bits\n");
+ ret = trace_seq_puts(s, "\ttime_delta : 27 bits\n");
+ ret = trace_seq_puts(s, "\tarray : 32 bits\n");
+ ret = trace_seq_putc(s, '\n');
ret = trace_seq_printf(s, "\tpadding : type == %d\n",
RINGBUF_TYPE_PADDING);
ret = trace_seq_printf(s, "\ttime_extend : type == %d\n",
@@ -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;
}
/**
@@ -613,10 +616,6 @@ int ring_buffer_poll_wait(struct ring_buffer *buffer, int cpu,
struct ring_buffer_per_cpu *cpu_buffer;
struct rb_irq_work *work;
- if ((cpu == RING_BUFFER_ALL_CPUS && !ring_buffer_empty(buffer)) ||
- (cpu != RING_BUFFER_ALL_CPUS && !ring_buffer_empty_cpu(buffer, cpu)))
- return POLLIN | POLLRDNORM;
-
if (cpu == RING_BUFFER_ALL_CPUS)
work = &buffer->irq_work;
else {
@@ -1066,7 +1065,7 @@ static int rb_check_list(struct ring_buffer_per_cpu *cpu_buffer,
}
/**
- * check_pages - integrity check of buffer pages
+ * rb_check_pages - integrity check of buffer pages
* @cpu_buffer: CPU buffer with pages to test
*
* As a safety measure we check to make sure the data pages have not
@@ -1258,7 +1257,7 @@ static int rb_cpu_notify(struct notifier_block *self,
#endif
/**
- * ring_buffer_alloc - allocate a new ring_buffer
+ * __ring_buffer_alloc - allocate a new ring_buffer
* @size: the size in bytes per cpu that is needed.
* @flags: attributes to set for the ring buffer.
*
@@ -1301,7 +1300,7 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
* In that off case, we need to allocate for all possible cpus.
*/
#ifdef CONFIG_HOTPLUG_CPU
- get_online_cpus();
+ cpu_notifier_register_begin();
cpumask_copy(buffer->cpumask, cpu_online_mask);
#else
cpumask_copy(buffer->cpumask, cpu_possible_mask);
@@ -1324,10 +1323,10 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
#ifdef CONFIG_HOTPLUG_CPU
buffer->cpu_notify.notifier_call = rb_cpu_notify;
buffer->cpu_notify.priority = 0;
- register_cpu_notifier(&buffer->cpu_notify);
+ __register_cpu_notifier(&buffer->cpu_notify);
+ cpu_notifier_register_done();
#endif
- put_online_cpus();
mutex_init(&buffer->mutex);
return buffer;
@@ -1341,7 +1340,9 @@ struct ring_buffer *__ring_buffer_alloc(unsigned long size, unsigned flags,
fail_free_cpumask:
free_cpumask_var(buffer->cpumask);
- put_online_cpus();
+#ifdef CONFIG_HOTPLUG_CPU
+ cpu_notifier_register_done();
+#endif
fail_free_buffer:
kfree(buffer);
@@ -1358,16 +1359,17 @@ ring_buffer_free(struct ring_buffer *buffer)
{
int cpu;
- get_online_cpus();
-
#ifdef CONFIG_HOTPLUG_CPU
- unregister_cpu_notifier(&buffer->cpu_notify);
+ cpu_notifier_register_begin();
+ __unregister_cpu_notifier(&buffer->cpu_notify);
#endif
for_each_buffer_cpu(buffer, cpu)
rb_free_cpu_buffer(buffer->buffers[cpu]);
- put_online_cpus();
+#ifdef CONFIG_HOTPLUG_CPU
+ cpu_notifier_register_done();
+#endif
kfree(buffer->buffers);
free_cpumask_var(buffer->cpumask);
@@ -1607,6 +1609,7 @@ static void update_pages_handler(struct work_struct *work)
* ring_buffer_resize - resize the ring buffer
* @buffer: the buffer to resize.
* @size: the new size.
+ * @cpu_id: the cpu buffer to resize
*
* Minimum size is 2 * BUF_PAGE_SIZE.
*
@@ -2396,6 +2399,13 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer,
write &= RB_WRITE_MASK;
tail = write - length;
+ /*
+ * If this is the first commit on the page, then it has the same
+ * timestamp as the page itself.
+ */
+ if (!tail)
+ delta = 0;
+
/* See if we shot pass the end of this buffer page */
if (unlikely(write > BUF_PAGE_SIZE))
return rb_move_tail(cpu_buffer, length, tail,
@@ -2557,7 +2567,7 @@ rb_reserve_next_event(struct ring_buffer *buffer,
if (unlikely(test_time_stamp(delta))) {
int local_clock_stable = 1;
#ifdef CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
- local_clock_stable = sched_clock_stable;
+ local_clock_stable = sched_clock_stable();
#endif
WARN_ONCE(delta > (1ULL << 59),
KERN_WARNING "Delta way too big! %llu ts=%llu write stamp = %llu\n%s",
@@ -3956,11 +3966,11 @@ EXPORT_SYMBOL_GPL(ring_buffer_consume);
* expected.
*
* After a sequence of ring_buffer_read_prepare calls, the user is
- * expected to make at least one call to ring_buffer_prepare_sync.
+ * expected to make at least one call to ring_buffer_read_prepare_sync.
* Afterwards, ring_buffer_read_start is invoked to get things going
* for real.
*
- * This overall must be paired with ring_buffer_finish.
+ * This overall must be paired with ring_buffer_read_finish.
*/
struct ring_buffer_iter *
ring_buffer_read_prepare(struct ring_buffer *buffer, int cpu)
@@ -4009,7 +4019,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_read_prepare_sync);
* an intervening ring_buffer_read_prepare_sync must have been
* performed.
*
- * Must be paired with ring_buffer_finish.
+ * Must be paired with ring_buffer_read_finish.
*/
void
ring_buffer_read_start(struct ring_buffer_iter *iter)
@@ -4031,7 +4041,7 @@ ring_buffer_read_start(struct ring_buffer_iter *iter)
EXPORT_SYMBOL_GPL(ring_buffer_read_start);
/**
- * ring_buffer_finish - finish reading the iterator of the buffer
+ * ring_buffer_read_finish - finish reading the iterator of the buffer
* @iter: The iterator retrieved by ring_buffer_start
*
* This re-enables the recording to the buffer, and frees the
@@ -4346,6 +4356,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_swap_cpu);
/**
* ring_buffer_alloc_read_page - allocate a page to read from buffer
* @buffer: the buffer to allocate for.
+ * @cpu: the cpu buffer to allocate.
*
* This function is used in conjunction with ring_buffer_read_page.
* When reading a full page from the ring buffer, these functions
@@ -4403,7 +4414,7 @@ EXPORT_SYMBOL_GPL(ring_buffer_free_read_page);
* to swap with a page in the ring buffer.
*
* for example:
- * rpage = ring_buffer_alloc_read_page(buffer);
+ * rpage = ring_buffer_alloc_read_page(buffer, cpu);
* if (!rpage)
* return error;
* ret = ring_buffer_read_page(buffer, &rpage, len, cpu, 0);