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-rw-r--r--kernel/trace/ring_buffer.c55
1 files changed, 31 insertions, 24 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index bd38c5cfd8ad..b36d7374ceef 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -123,8 +123,7 @@ void ring_buffer_normalize_time_stamp(int cpu, u64 *ts)
EXPORT_SYMBOL_GPL(ring_buffer_normalize_time_stamp);
#define RB_EVNT_HDR_SIZE (sizeof(struct ring_buffer_event))
-#define RB_ALIGNMENT_SHIFT 2
-#define RB_ALIGNMENT (1 << RB_ALIGNMENT_SHIFT)
+#define RB_ALIGNMENT 4U
#define RB_MAX_SMALL_DATA 28
enum {
@@ -133,7 +132,7 @@ enum {
};
/* inline for ring buffer fast paths */
-static inline unsigned
+static unsigned
rb_event_length(struct ring_buffer_event *event)
{
unsigned length;
@@ -151,7 +150,7 @@ rb_event_length(struct ring_buffer_event *event)
case RINGBUF_TYPE_DATA:
if (event->len)
- length = event->len << RB_ALIGNMENT_SHIFT;
+ length = event->len * RB_ALIGNMENT;
else
length = event->array[0];
return length + RB_EVNT_HDR_SIZE;
@@ -179,7 +178,7 @@ unsigned ring_buffer_event_length(struct ring_buffer_event *event)
EXPORT_SYMBOL_GPL(ring_buffer_event_length);
/* inline for ring buffer fast paths */
-static inline void *
+static void *
rb_event_data(struct ring_buffer_event *event)
{
BUG_ON(event->type != RINGBUF_TYPE_DATA);
@@ -229,10 +228,9 @@ static void rb_init_page(struct buffer_data_page *bpage)
* Also stolen from mm/slob.c. Thanks to Mathieu Desnoyers for pointing
* this issue out.
*/
-static inline void free_buffer_page(struct buffer_page *bpage)
+static void free_buffer_page(struct buffer_page *bpage)
{
- if (bpage->page)
- free_page((unsigned long)bpage->page);
+ free_page((unsigned long)bpage->page);
kfree(bpage);
}
@@ -811,7 +809,7 @@ rb_event_index(struct ring_buffer_event *event)
return (addr & ~PAGE_MASK) - (PAGE_SIZE - BUF_PAGE_SIZE);
}
-static inline int
+static int
rb_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event)
{
@@ -825,7 +823,7 @@ rb_is_commit(struct ring_buffer_per_cpu *cpu_buffer,
rb_commit_index(cpu_buffer) == index;
}
-static inline void
+static void
rb_set_commit_event(struct ring_buffer_per_cpu *cpu_buffer,
struct ring_buffer_event *event)
{
@@ -850,7 +848,7 @@ rb_set_commit_event(struct ring_buffer_per_cpu *cpu_buffer,
local_set(&cpu_buffer->commit_page->page->commit, index);
}
-static inline void
+static void
rb_set_commit_to_write(struct ring_buffer_per_cpu *cpu_buffer)
{
/*
@@ -896,7 +894,7 @@ static void rb_reset_reader_page(struct ring_buffer_per_cpu *cpu_buffer)
cpu_buffer->reader_page->read = 0;
}
-static inline void rb_inc_iter(struct ring_buffer_iter *iter)
+static void rb_inc_iter(struct ring_buffer_iter *iter)
{
struct ring_buffer_per_cpu *cpu_buffer = iter->cpu_buffer;
@@ -926,7 +924,7 @@ static inline void rb_inc_iter(struct ring_buffer_iter *iter)
* and with this, we can determine what to place into the
* data field.
*/
-static inline void
+static void
rb_update_event(struct ring_buffer_event *event,
unsigned type, unsigned length)
{
@@ -938,15 +936,11 @@ rb_update_event(struct ring_buffer_event *event,
break;
case RINGBUF_TYPE_TIME_EXTEND:
- event->len =
- (RB_LEN_TIME_EXTEND + (RB_ALIGNMENT-1))
- >> RB_ALIGNMENT_SHIFT;
+ event->len = DIV_ROUND_UP(RB_LEN_TIME_EXTEND, RB_ALIGNMENT);
break;
case RINGBUF_TYPE_TIME_STAMP:
- event->len =
- (RB_LEN_TIME_STAMP + (RB_ALIGNMENT-1))
- >> RB_ALIGNMENT_SHIFT;
+ event->len = DIV_ROUND_UP(RB_LEN_TIME_STAMP, RB_ALIGNMENT);
break;
case RINGBUF_TYPE_DATA:
@@ -955,16 +949,14 @@ rb_update_event(struct ring_buffer_event *event,
event->len = 0;
event->array[0] = length;
} else
- event->len =
- (length + (RB_ALIGNMENT-1))
- >> RB_ALIGNMENT_SHIFT;
+ event->len = DIV_ROUND_UP(length, RB_ALIGNMENT);
break;
default:
BUG();
}
}
-static inline unsigned rb_calculate_event_length(unsigned length)
+static unsigned rb_calculate_event_length(unsigned length)
{
struct ring_buffer_event event; /* Used only for sizeof array */
@@ -1438,7 +1430,7 @@ int ring_buffer_write(struct ring_buffer *buffer,
}
EXPORT_SYMBOL_GPL(ring_buffer_write);
-static inline int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer)
+static int rb_per_cpu_empty(struct ring_buffer_per_cpu *cpu_buffer)
{
struct buffer_page *reader = cpu_buffer->reader_page;
struct buffer_page *head = cpu_buffer->head_page;
@@ -2277,9 +2269,24 @@ int ring_buffer_swap_cpu(struct ring_buffer *buffer_a,
if (buffer_a->pages != buffer_b->pages)
return -EINVAL;
+ if (ring_buffer_flags != RB_BUFFERS_ON)
+ return -EAGAIN;
+
+ if (atomic_read(&buffer_a->record_disabled))
+ return -EAGAIN;
+
+ if (atomic_read(&buffer_b->record_disabled))
+ return -EAGAIN;
+
cpu_buffer_a = buffer_a->buffers[cpu];
cpu_buffer_b = buffer_b->buffers[cpu];
+ if (atomic_read(&cpu_buffer_a->record_disabled))
+ return -EAGAIN;
+
+ if (atomic_read(&cpu_buffer_b->record_disabled))
+ return -EAGAIN;
+
/*
* We can't do a synchronize_sched here because this
* function can be called in atomic context.