[PATCH V2 05/12] nvmet: use unlikely for uncommon commands

[Chaitanya Kulkarni]

I/O commands (nvme_cmd_read, nvme_cmd_write) are most common commands
when accessing passthru controller, most controllers should not
have set the effects for r/w I/O commnds (atleast I don't know at this
moment). Also, check for req->p.use_workqueue is true in two admin
commands only which are low frequency commands.

Annotate use_workqueue and command effects check with unlikely in the
fast path.

Signed-off-by: Chaitanya Kulkarni <chaitanya.kulkarni at wdc.com>
---
 drivers/nvme/target/passthru.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/nvme/target/passthru.c b/drivers/nvme/target/passthru.c
index 682291fb6d7b..8f9c2144a103 100644
--- a/drivers/nvme/target/passthru.c
+++ b/drivers/nvme/target/passthru.c
@@ -258,7 +258,7 @@ static void nvmet_passthru_execute_cmd(struct nvmet_req *req)
 	 * which is typically in interrupt context.
 	 */
 	effects = nvme_command_effects(ctrl, ns, req->cmd->common.opcode);
-	if (req->p.use_workqueue || effects) {
+	if (unlikely(req->p.use_workqueue || effects)) {
 		INIT_WORK(&req->p.work, nvmet_passthru_execute_cmd_work);
 		req->p.rq = rq;
 		schedule_work(&req->p.work);
-- 
2.22.1