block: export trace_block_unplug

This allows stacked devices (like md/raid5) to provide blktrace
tracing, including unplug events.

Reported-by: Fengguang Wu <fengguang.wu@intel.com>
Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/block/blk-core.c b/block/blk-core.c
index 4b4dbdfbca89fe5769fd4b2f6826f305fca18e26..ef55ae0f58aca78d31857bfd9098b265394efc36 100644 (file)
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -40,6 +40,7 @@
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_remap);
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_rq_remap);
 EXPORT_TRACEPOINT_SYMBOL_GPL(block_bio_complete);
+EXPORT_TRACEPOINT_SYMBOL_GPL(block_unplug);
 
 DEFINE_IDA(blk_queue_ida);