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-rw-r--r--Documentation/perf_counter/kerneltop.c14
1 files changed, 1 insertions, 13 deletions
diff --git a/Documentation/perf_counter/kerneltop.c b/Documentation/perf_counter/kerneltop.c
index fda1438365d..2779c57ad4b 100644
--- a/Documentation/perf_counter/kerneltop.c
+++ b/Documentation/perf_counter/kerneltop.c
@@ -1125,22 +1125,10 @@ struct mmap_data {
static unsigned int mmap_read_head(struct mmap_data *md)
{
struct perf_counter_mmap_page *pc = md->base;
- unsigned int seq, head;
-
-repeat:
- rmb();
- seq = pc->lock;
-
- if (unlikely(seq & 1)) {
- cpu_relax();
- goto repeat;
- }
+ int head;
head = pc->data_head;
-
rmb();
- if (pc->lock != seq)
- goto repeat;
return head;
}