io_uring: remove trace for eventfd

The information on whether eventfd is registered is not very useful and
would result in the tracepoint being enclosed in an rcu_readlock in a
later patch that tries to avoid ring quiesce for registering eventfd.
Suggested-by: NJens Axboe <axboe@kernel.dk>
Signed-off-by: NUsama Arif <usama.arif@bytedance.com>
Link: https://lore.kernel.org/r/20220204145117.1186568-2-usama.arif@bytedance.comSigned-off-by: NJens Axboe <axboe@kernel.dk>

fs/io_uring.c

@@ -11179,8 +11179,7 @@ SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
 	mutex_lock(&ctx->uring_lock);
 	ret = __io_uring_register(ctx, opcode, arg, nr_args);
 	mutex_unlock(&ctx->uring_lock);
-	trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
-							ctx->cq_ev_fd != NULL, ret);
+	trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs, ret);
 out_fput:
 	fdput(f);
 	return ret;

include/trace/events/io_uring.h

@@ -57,10 +57,9 @@ TRACE_EVENT(io_uring_create,
  * @opcode:		describes which operation to perform
  * @nr_user_files:	number of registered files
  * @nr_user_bufs:	number of registered buffers
- * @cq_ev_fd:		whether eventfs registered or not
  * @ret:		return code
  *
- * Allows to trace fixed files/buffers/eventfds, that could be registered to
+ * Allows to trace fixed files/buffers, that could be registered to
  * avoid an overhead of getting references to them for every operation. This
  * event, together with io_uring_file_get, can provide a full picture of how
  * much overhead one can reduce via fixing.
@@ -68,16 +67,15 @@ TRACE_EVENT(io_uring_create,
 TRACE_EVENT(io_uring_register,
 
 	TP_PROTO(void *ctx, unsigned opcode, unsigned nr_files,
-			 unsigned nr_bufs, bool eventfd, long ret),
+			 unsigned nr_bufs, long ret),
 
-	TP_ARGS(ctx, opcode, nr_files, nr_bufs, eventfd, ret),
+	TP_ARGS(ctx, opcode, nr_files, nr_bufs, ret),
 
 	TP_STRUCT__entry (
 		__field(  void *,	ctx			)
 		__field(  unsigned,	opcode		)
 		__field(  unsigned,	nr_files	)
 		__field(  unsigned,	nr_bufs		)
-		__field(  bool,		eventfd		)
 		__field(  long,		ret			)
 	),
 
@@ -86,14 +84,13 @@ TRACE_EVENT(io_uring_register,
 		__entry->opcode		= opcode;
 		__entry->nr_files	= nr_files;
 		__entry->nr_bufs	= nr_bufs;
-		__entry->eventfd	= eventfd;
 		__entry->ret		= ret;
 	),
 
 	TP_printk("ring %p, opcode %d, nr_user_files %d, nr_user_bufs %d, "
-			  "eventfd %d, ret %ld",
+			  "ret %ld",
 			  __entry->ctx, __entry->opcode, __entry->nr_files,
-			  __entry->nr_bufs, __entry->eventfd, __entry->ret)
+			  __entry->nr_bufs, __entry->ret)
 );
 
 /**