libceph: pass the message pointer instead of loading con->out_msg

This pointer is in a register anyway, so let's use that instead of
reloading from memory everywhere.

[ idryomov: formatting ]

Signed-off-by: Max Kellermann <[e-mail]>
Reviewed-by: Viacheslav Dubeyko <[e-mail]>
Signed-off-by: Ilya Dryomov <[e-mail]>

include/linux/ceph/messenger.h

···
 /* messenger_v1.c */
 int ceph_con_v1_try_read(struct ceph_connection *con);
 int ceph_con_v1_try_write(struct ceph_connection *con);
-void ceph_con_v1_revoke(struct ceph_connection *con);
+void ceph_con_v1_revoke(struct ceph_connection *con, struct ceph_msg *msg);
 void ceph_con_v1_revoke_incoming(struct ceph_connection *con);
 bool ceph_con_v1_opened(struct ceph_connection *con);
 void ceph_con_v1_reset_session(struct ceph_connection *con);
···
 /* messenger_v2.c */
 int ceph_con_v2_try_read(struct ceph_connection *con);
 int ceph_con_v2_try_write(struct ceph_connection *con);
-void ceph_con_v2_revoke(struct ceph_connection *con);
+void ceph_con_v2_revoke(struct ceph_connection *con, struct ceph_msg *msg);
 void ceph_con_v2_revoke_incoming(struct ceph_connection *con);
 bool ceph_con_v2_opened(struct ceph_connection *con);
 void ceph_con_v2_reset_session(struct ceph_connection *con);

net/ceph/messenger.c

···
 		WARN_ON(con->state != CEPH_CON_S_OPEN);
 		dout("%s con %p msg %p was sending\n", __func__, con, msg);
 		if (ceph_msgr2(from_msgr(con->msgr)))
-			ceph_con_v2_revoke(con);
+			ceph_con_v2_revoke(con, msg);
 		else
-			ceph_con_v1_revoke(con);
+			ceph_con_v1_revoke(con, msg);
 		ceph_msg_put(con->out_msg);
 		con->out_msg = NULL;
 	} else {

net/ceph/messenger_v1.c

···
  * Prepare footer for currently outgoing message, and finish things
  * off.  Assumes out_kvec* are already valid.. we just add on to the end.
  */
-static void prepare_write_message_footer(struct ceph_connection *con)
+static void prepare_write_message_footer(struct ceph_connection *con,
+					 struct ceph_msg *m)
 {
-	struct ceph_msg *m = con->out_msg;
-
 	m->footer.flags |= CEPH_MSG_FOOTER_COMPLETE;
 
 	dout("prepare_write_message_footer %p\n", con);
···
 
 	/* fill in hdr crc and finalize hdr */
 	crc = crc32c(0, &m->hdr, offsetof(struct ceph_msg_header, crc));
-	con->out_msg->hdr.crc = cpu_to_le32(crc);
-	memcpy(&con->v1.out_hdr, &con->out_msg->hdr, sizeof(con->v1.out_hdr));
+	m->hdr.crc = cpu_to_le32(crc);
+	memcpy(&con->v1.out_hdr, &m->hdr, sizeof(con->v1.out_hdr));
 
 	/* fill in front and middle crc, footer */
 	crc = crc32c(0, m->front.iov_base, m->front.iov_len);
-	con->out_msg->footer.front_crc = cpu_to_le32(crc);
+	m->footer.front_crc = cpu_to_le32(crc);
 	if (m->middle) {
 		crc = crc32c(0, m->middle->vec.iov_base,
 				m->middle->vec.iov_len);
-		con->out_msg->footer.middle_crc = cpu_to_le32(crc);
+		m->footer.middle_crc = cpu_to_le32(crc);
 	} else
-		con->out_msg->footer.middle_crc = 0;
+		m->footer.middle_crc = 0;
 	dout("%s front_crc %u middle_crc %u\n", __func__,
-	     le32_to_cpu(con->out_msg->footer.front_crc),
-	     le32_to_cpu(con->out_msg->footer.middle_crc));
-	con->out_msg->footer.flags = 0;
+	     le32_to_cpu(m->footer.front_crc),
+	     le32_to_cpu(m->footer.middle_crc));
+	m->footer.flags = 0;
 
 	/* is there a data payload? */
-	con->out_msg->footer.data_crc = 0;
+	m->footer.data_crc = 0;
 	if (m->data_length) {
-		prepare_message_data(con->out_msg, m->data_length);
+		prepare_message_data(m, m->data_length);
 		con->v1.out_more = 1;  /* data + footer will follow */
 	} else {
 		/* no, queue up footer too and be done */
-		prepare_write_message_footer(con);
+		prepare_write_message_footer(con, m);
 	}
 
 	ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
···
  *  0 -> socket full, but more to do
  * <0 -> error
  */
-static int write_partial_message_data(struct ceph_connection *con)
+static int write_partial_message_data(struct ceph_connection *con,
+				      struct ceph_msg *msg)
 {
-	struct ceph_msg *msg = con->out_msg;
 	struct ceph_msg_data_cursor *cursor = &msg->cursor;
 	bool do_datacrc = !ceph_test_opt(from_msgr(con->msgr), NOCRC);
 	u32 crc;
···
 	else
 		msg->footer.flags |= CEPH_MSG_FOOTER_NOCRC;
 	con_out_kvec_reset(con);
-	prepare_write_message_footer(con);
+	prepare_write_message_footer(con, msg);
 
 	return 1;	/* must return > 0 to indicate success */
 }
···
  */
 int ceph_con_v1_try_write(struct ceph_connection *con)
 {
+	struct ceph_msg *msg;
 	int ret = 1;
 
 	dout("try_write start %p state %d\n", con, con->state);
···
 	}
 
 	/* msg pages? */
-	if (con->out_msg) {
+	msg = con->out_msg;
+	if (msg) {
 		if (con->v1.out_msg_done) {
-			ceph_msg_put(con->out_msg);
+			ceph_msg_put(msg);
 			con->out_msg = NULL;   /* we're done with this one */
 			goto do_next;
 		}
 
-		ret = write_partial_message_data(con);
+		ret = write_partial_message_data(con, msg);
 		if (ret == 1)
 			goto more;  /* we need to send the footer, too! */
 		if (ret == 0)
···
 	return ret;
 }
 
-void ceph_con_v1_revoke(struct ceph_connection *con)
+void ceph_con_v1_revoke(struct ceph_connection *con, struct ceph_msg *msg)
 {
-	struct ceph_msg *msg = con->out_msg;
-
 	WARN_ON(con->v1.out_skip);
 	/* footer */
 	if (con->v1.out_msg_done) {

net/ceph/messenger_v2.c

···
 	return prepare_control(con, FRAME_TAG_ACK, con->v2.out_buf, 8);
 }
 
-static void prepare_epilogue_plain(struct ceph_connection *con, bool aborted)
+static void prepare_epilogue_plain(struct ceph_connection *con,
+				   struct ceph_msg *msg, bool aborted)
 {
 	dout("%s con %p msg %p aborted %d crcs %u %u %u\n", __func__, con,
-	     con->out_msg, aborted, con->v2.out_epil.front_crc,
+	     msg, aborted, con->v2.out_epil.front_crc,
 	     con->v2.out_epil.middle_crc, con->v2.out_epil.data_crc);
 
 	encode_epilogue_plain(con, aborted);
···
  * For "used" empty segments, crc is -1.  For unused (trailing)
  * segments, crc is 0.
  */
-static void prepare_message_plain(struct ceph_connection *con)
+static void prepare_message_plain(struct ceph_connection *con,
+				  struct ceph_msg *msg)
 {
-	struct ceph_msg *msg = con->out_msg;
-
 	prepare_head_plain(con, con->v2.out_buf,
 			   sizeof(struct ceph_msg_header2), NULL, 0, false);
 
···
 		con->v2.out_state = OUT_S_QUEUE_DATA;
 	} else {
 		con->v2.out_epil.data_crc = 0;
-		prepare_epilogue_plain(con, false);
+		prepare_epilogue_plain(con, msg, false);
 		con->v2.out_state = OUT_S_FINISH_MESSAGE;
 	}
 }
···
  * allocate pages for the entire tail of the message (currently up
  * to ~32M) and two sgs arrays (up to ~256K each)...
  */
-static int prepare_message_secure(struct ceph_connection *con)
+static int prepare_message_secure(struct ceph_connection *con,
+				  struct ceph_msg *msg)
 {
 	void *zerop = page_address(ceph_zero_page);
 	struct sg_table enc_sgt = {};
···
 	if (ret)
 		return ret;
 
-	tail_len = tail_onwire_len(con->out_msg, true);
+	tail_len = tail_onwire_len(msg, true);
 	if (!tail_len) {
 		/*
 		 * Empty message: once the head is written,
···
 	}
 
 	encode_epilogue_secure(con, false);
-	ret = setup_message_sgs(&sgt, con->out_msg, zerop, zerop, zerop,
+	ret = setup_message_sgs(&sgt, msg, zerop, zerop, zerop,
 				&con->v2.out_epil, NULL, 0, false);
 	if (ret)
 		goto out;
···
 		goto out;
 
 	dout("%s con %p msg %p sg_cnt %d enc_page_cnt %d\n", __func__, con,
-	     con->out_msg, sgt.orig_nents, enc_page_cnt);
+	     msg, sgt.orig_nents, enc_page_cnt);
 	con->v2.out_state = OUT_S_QUEUE_ENC_PAGE;
 
 out:
···
 	return ret;
 }
 
-static int prepare_message(struct ceph_connection *con)
+static int prepare_message(struct ceph_connection *con, struct ceph_msg *msg)
 {
 	int lens[] = {
 		sizeof(struct ceph_msg_header2),
-		front_len(con->out_msg),
-		middle_len(con->out_msg),
-		data_len(con->out_msg)
+		front_len(msg),
+		middle_len(msg),
+		data_len(msg)
 	};
 	struct ceph_frame_desc desc;
 	int ret;
 
 	dout("%s con %p msg %p logical %d+%d+%d+%d\n", __func__, con,
-	     con->out_msg, lens[0], lens[1], lens[2], lens[3]);
+	     msg, lens[0], lens[1], lens[2], lens[3]);
 
 	if (con->in_seq > con->in_seq_acked) {
 		dout("%s con %p in_seq_acked %llu -> %llu\n", __func__, con,
···
 	reset_out_kvecs(con);
 	init_frame_desc(&desc, FRAME_TAG_MESSAGE, lens, 4);
 	encode_preamble(&desc, con->v2.out_buf);
-	fill_header2(CTRL_BODY(con->v2.out_buf), &con->out_msg->hdr,
+	fill_header2(CTRL_BODY(con->v2.out_buf), &msg->hdr,
 		     con->in_seq_acked);
 
 	if (con_secure(con)) {
-		ret = prepare_message_secure(con);
+		ret = prepare_message_secure(con, msg);
 		if (ret)
 			return ret;
 	} else {
-		prepare_message_plain(con);
+		prepare_message_plain(con, msg);
 	}
 
 	ceph_con_flag_set(con, CEPH_CON_F_WRITE_PENDING);
···
 	}
 }
 
-static void queue_data(struct ceph_connection *con)
+static void queue_data(struct ceph_connection *con, struct ceph_msg *msg)
 {
 	struct bio_vec bv;
 
 	con->v2.out_epil.data_crc = -1;
-	ceph_msg_data_cursor_init(&con->v2.out_cursor, con->out_msg,
-				  data_len(con->out_msg));
+	ceph_msg_data_cursor_init(&con->v2.out_cursor, msg,
+				  data_len(msg));
 
 	get_bvec_at(&con->v2.out_cursor, &bv);
 	set_out_bvec(con, &bv, true);
 	con->v2.out_state = OUT_S_QUEUE_DATA_CONT;
 }
 
-static void queue_data_cont(struct ceph_connection *con)
+static void queue_data_cont(struct ceph_connection *con, struct ceph_msg *msg)
 {
 	struct bio_vec bv;
 
···
 	 * we are done.
 	 */
 	reset_out_kvecs(con);
-	prepare_epilogue_plain(con, false);
+	prepare_epilogue_plain(con, msg, false);
 	con->v2.out_state = OUT_S_FINISH_MESSAGE;
 }
 
···
 	con->v2.out_state = OUT_S_FINISH_MESSAGE;
 }
 
-static void queue_zeros(struct ceph_connection *con)
+static void queue_zeros(struct ceph_connection *con, struct ceph_msg *msg)
 {
 	dout("%s con %p out_zero %d\n", __func__, con, con->v2.out_zero);
 
···
 	 * Once it's written, we are done patching up for the revoke.
 	 */
 	reset_out_kvecs(con);
-	prepare_epilogue_plain(con, true);
+	prepare_epilogue_plain(con, msg, true);
 	con->v2.out_state = OUT_S_FINISH_MESSAGE;
 }
 
···
 
 static int populate_out_iter(struct ceph_connection *con)
 {
+	struct ceph_msg *msg;
 	int ret;
 
 	dout("%s con %p state %d out_state %d\n", __func__, con, con->state,
···
 	switch (con->v2.out_state) {
 	case OUT_S_QUEUE_DATA:
 		WARN_ON(!con->out_msg);
-		queue_data(con);
+		queue_data(con, con->out_msg);
 		goto populated;
 	case OUT_S_QUEUE_DATA_CONT:
 		WARN_ON(!con->out_msg);
-		queue_data_cont(con);
+		queue_data_cont(con, con->out_msg);
 		goto populated;
 	case OUT_S_QUEUE_ENC_PAGE:
 		queue_enc_page(con);
 		goto populated;
 	case OUT_S_QUEUE_ZEROS:
 		WARN_ON(con->out_msg);  /* revoked */
-		queue_zeros(con);
+		queue_zeros(con, con->out_msg);
 		goto populated;
 	case OUT_S_FINISH_MESSAGE:
 		finish_message(con);
···
 			return ret;
 		}
 	} else if (!list_empty(&con->out_queue)) {
-		ceph_con_get_out_msg(con);
-		ret = prepare_message(con);
+		msg = ceph_con_get_out_msg(con);
+		ret = prepare_message(con, msg);
 		if (ret) {
 			pr_err("prepare_message failed: %d\n", ret);
 			return ret;
···
 	return crc;
 }
 
-static void prepare_zero_front(struct ceph_connection *con, int resid)
+static void prepare_zero_front(struct ceph_connection *con,
+			       struct ceph_msg *msg, int resid)
 {
 	int sent;
 
-	WARN_ON(!resid || resid > front_len(con->out_msg));
-	sent = front_len(con->out_msg) - resid;
+	WARN_ON(!resid || resid > front_len(msg));
+	sent = front_len(msg) - resid;
 	dout("%s con %p sent %d resid %d\n", __func__, con, sent, resid);
 
 	if (sent) {
 		con->v2.out_epil.front_crc =
-			crc32c(-1, con->out_msg->front.iov_base, sent);
+			crc32c(-1, msg->front.iov_base, sent);
 		con->v2.out_epil.front_crc =
 			crc32c_zeros(con->v2.out_epil.front_crc, resid);
 	} else {
···
 	out_zero_add(con, resid);
 }
 
-static void prepare_zero_middle(struct ceph_connection *con, int resid)
+static void prepare_zero_middle(struct ceph_connection *con,
+				struct ceph_msg *msg, int resid)
 {
 	int sent;
 
-	WARN_ON(!resid || resid > middle_len(con->out_msg));
-	sent = middle_len(con->out_msg) - resid;
+	WARN_ON(!resid || resid > middle_len(msg));
+	sent = middle_len(msg) - resid;
 	dout("%s con %p sent %d resid %d\n", __func__, con, sent, resid);
 
 	if (sent) {
 		con->v2.out_epil.middle_crc =
-			crc32c(-1, con->out_msg->middle->vec.iov_base, sent);
+			crc32c(-1, msg->middle->vec.iov_base, sent);
 		con->v2.out_epil.middle_crc =
 			crc32c_zeros(con->v2.out_epil.middle_crc, resid);
 	} else {
···
 	out_zero_add(con, resid);
 }
 
-static void prepare_zero_data(struct ceph_connection *con)
+static void prepare_zero_data(struct ceph_connection *con,
+			      struct ceph_msg *msg)
 {
 	dout("%s con %p\n", __func__, con);
-	con->v2.out_epil.data_crc = crc32c_zeros(-1, data_len(con->out_msg));
-	out_zero_add(con, data_len(con->out_msg));
+	con->v2.out_epil.data_crc = crc32c_zeros(-1, data_len(msg));
+	out_zero_add(con, data_len(msg));
 }
 
-static void revoke_at_queue_data(struct ceph_connection *con)
+static void revoke_at_queue_data(struct ceph_connection *con,
+				 struct ceph_msg *msg)
 {
 	int boundary;
 	int resid;
 
-	WARN_ON(!data_len(con->out_msg));
+	WARN_ON(!data_len(msg));
 	WARN_ON(!iov_iter_is_kvec(&con->v2.out_iter));
 	resid = iov_iter_count(&con->v2.out_iter);
 
-	boundary = front_len(con->out_msg) + middle_len(con->out_msg);
+	boundary = front_len(msg) + middle_len(msg);
 	if (resid > boundary) {
 		resid -= boundary;
 		WARN_ON(resid > MESSAGE_HEAD_PLAIN_LEN);
 		dout("%s con %p was sending head\n", __func__, con);
-		if (front_len(con->out_msg))
-			prepare_zero_front(con, front_len(con->out_msg));
-		if (middle_len(con->out_msg))
-			prepare_zero_middle(con, middle_len(con->out_msg));
-		prepare_zero_data(con);
+		if (front_len(msg))
+			prepare_zero_front(con, msg, front_len(msg));
+		if (middle_len(msg))
+			prepare_zero_middle(con, msg, middle_len(msg));
+		prepare_zero_data(con, msg);
 		WARN_ON(iov_iter_count(&con->v2.out_iter) != resid);
 		con->v2.out_state = OUT_S_QUEUE_ZEROS;
 		return;
 	}
 
-	boundary = middle_len(con->out_msg);
+	boundary = middle_len(msg);
 	if (resid > boundary) {
 		resid -= boundary;
 		dout("%s con %p was sending front\n", __func__, con);
-		prepare_zero_front(con, resid);
-		if (middle_len(con->out_msg))
-			prepare_zero_middle(con, middle_len(con->out_msg));
-		prepare_zero_data(con);
-		queue_zeros(con);
+		prepare_zero_front(con, msg, resid);
+		if (middle_len(msg))
+			prepare_zero_middle(con, msg, middle_len(msg));
+		prepare_zero_data(con, msg);
+		queue_zeros(con, msg);
 		return;
 	}
 
 	WARN_ON(!resid);
 	dout("%s con %p was sending middle\n", __func__, con);
-	prepare_zero_middle(con, resid);
-	prepare_zero_data(con);
-	queue_zeros(con);
+	prepare_zero_middle(con, msg, resid);
+	prepare_zero_data(con, msg);
+	queue_zeros(con, msg);
 }
 
-static void revoke_at_queue_data_cont(struct ceph_connection *con)
+static void revoke_at_queue_data_cont(struct ceph_connection *con,
+				      struct ceph_msg *msg)
 {
 	int sent, resid;  /* current piece of data */
 
-	WARN_ON(!data_len(con->out_msg));
+	WARN_ON(!data_len(msg));
 	WARN_ON(!iov_iter_is_bvec(&con->v2.out_iter));
 	resid = iov_iter_count(&con->v2.out_iter);
 	WARN_ON(!resid || resid > con->v2.out_bvec.bv_len);
···
 
 	con->v2.out_iter.count -= resid;
 	out_zero_add(con, con->v2.out_cursor.total_resid);
-	queue_zeros(con);
+	queue_zeros(con, msg);
 }
 
-static void revoke_at_finish_message(struct ceph_connection *con)
+static void revoke_at_finish_message(struct ceph_connection *con,
+				     struct ceph_msg *msg)
 {
 	int boundary;
 	int resid;
···
 	WARN_ON(!iov_iter_is_kvec(&con->v2.out_iter));
 	resid = iov_iter_count(&con->v2.out_iter);
 
-	if (!front_len(con->out_msg) && !middle_len(con->out_msg) &&
-	    !data_len(con->out_msg)) {
+	if (!front_len(msg) && !middle_len(msg) &&
+	    !data_len(msg)) {
 		WARN_ON(!resid || resid > MESSAGE_HEAD_PLAIN_LEN);
 		dout("%s con %p was sending head (empty message) - noop\n",
 		     __func__, con);
 		return;
 	}
 
-	boundary = front_len(con->out_msg) + middle_len(con->out_msg) +
+	boundary = front_len(msg) + middle_len(msg) +
 		   CEPH_EPILOGUE_PLAIN_LEN;
 	if (resid > boundary) {
 		resid -= boundary;
 		WARN_ON(resid > MESSAGE_HEAD_PLAIN_LEN);
 		dout("%s con %p was sending head\n", __func__, con);
-		if (front_len(con->out_msg))
-			prepare_zero_front(con, front_len(con->out_msg));
-		if (middle_len(con->out_msg))
-			prepare_zero_middle(con, middle_len(con->out_msg));
+		if (front_len(msg))
+			prepare_zero_front(con, msg, front_len(msg));
+		if (middle_len(msg))
+			prepare_zero_middle(con, msg, middle_len(msg));
 		con->v2.out_iter.count -= CEPH_EPILOGUE_PLAIN_LEN;
 		WARN_ON(iov_iter_count(&con->v2.out_iter) != resid);
 		con->v2.out_state = OUT_S_QUEUE_ZEROS;
 		return;
 	}
 
-	boundary = middle_len(con->out_msg) + CEPH_EPILOGUE_PLAIN_LEN;
+	boundary = middle_len(msg) + CEPH_EPILOGUE_PLAIN_LEN;
 	if (resid > boundary) {
 		resid -= boundary;
 		dout("%s con %p was sending front\n", __func__, con);
-		prepare_zero_front(con, resid);
-		if (middle_len(con->out_msg))
-			prepare_zero_middle(con, middle_len(con->out_msg));
+		prepare_zero_front(con, msg, resid);
+		if (middle_len(msg))
+			prepare_zero_middle(con, msg, middle_len(msg));
 		con->v2.out_iter.count -= CEPH_EPILOGUE_PLAIN_LEN;
-		queue_zeros(con);
+		queue_zeros(con, msg);
 		return;
 	}
 
···
 	if (resid > boundary) {
 		resid -= boundary;
 		dout("%s con %p was sending middle\n", __func__, con);
-		prepare_zero_middle(con, resid);
+		prepare_zero_middle(con, msg, resid);
 		con->v2.out_iter.count -= CEPH_EPILOGUE_PLAIN_LEN;
-		queue_zeros(con);
+		queue_zeros(con, msg);
 		return;
 	}
 
···
 	dout("%s con %p was sending epilogue - noop\n", __func__, con);
 }
 
-void ceph_con_v2_revoke(struct ceph_connection *con)
+void ceph_con_v2_revoke(struct ceph_connection *con, struct ceph_msg *msg)
 {
 	WARN_ON(con->v2.out_zero);
 
···
 
 	switch (con->v2.out_state) {
 	case OUT_S_QUEUE_DATA:
-		revoke_at_queue_data(con);
+		revoke_at_queue_data(con, msg);
 		break;
 	case OUT_S_QUEUE_DATA_CONT:
-		revoke_at_queue_data_cont(con);
+		revoke_at_queue_data_cont(con, msg);
 		break;
 	case OUT_S_FINISH_MESSAGE:
-		revoke_at_finish_message(con);
+		revoke_at_finish_message(con, msg);
 		break;
 	default:
 		WARN(1, "bad out_state %d", con->v2.out_state);