[M] Change in libosmo-sigtran[master]: ASP loadsharing: Pass ownership of Rx xua_msg up the stack [2/2] - gerrit-log

6 Mar 2025

pespin has submitted this change. ( https://gerrit.osmocom.org/c/libosmo-sigtran/+/39397?usp=email )
(
11 is the latest approved patch-set.
No files were changed between the latest approved patch-set and the submitted one.
 )Change subject: ASP loadsharing: Pass ownership of Rx xua_msg up the stack [2/2]
......................................................................
ASP loadsharing: Pass ownership of Rx xua_msg up the stack [2/2]
This is the second step patch where we also pass ownership on Rx path so
that forwarded xua_msgs can be passed back to the Tx path without
freeing them.
For SUA there's no change needed and we keep freeing the rx xua_msg
right at the end of sua_rx_msg() since there's no actual path forwarding
a xua_msg object back into Tx path, it always goes through upper layers
using newly allocated primitives.
Related: SYS#7112
Change-Id: Icf3b4dda550637f722a9fe56d0313f49c8a2964e
---
M src/ipa.c
M src/m3ua.c
M src/xua_rkm.c
3 files changed, 58 insertions(+), 34 deletions(-)
Approvals:
  laforge: Looks good to me, but someone else must approve
  osmith: Looks good to me, but someone else must approve
  pespin: Looks good to me, approved
  Jenkins Builder: Verified

diff --git a/src/ipa.c b/src/ipa.c
index 47ddc0d..bbe94d1 100644
--- a/src/ipa.c
+++ b/src/ipa.c
@@ -302,9 +302,9 @@
    /* Update xua->mtp with values from data_hdr */
    m3ua_dh_to_xfer_param(&xua->mtp, &data_hdr);
-	/* Pass on as if we had received it from an M3UA ASP */
+	/* Pass on as if we had received it from an M3UA ASP.
+	 * xua ownership is passed here: */
    rc = m3ua_hmdc_rx_from_l2(asp->inst, xua);
-	xua_msg_free(xua);
    return rc;
 }
diff --git a/src/m3ua.c b/src/m3ua.c
index cdbfc48..8232d7b 100644
--- a/src/m3ua.c
+++ b/src/m3ua.c
@@ -579,6 +579,7 @@
    return data_hdr;
 }
+/* This function takes ownership of xua msg passed to it. */
 static int m3ua_rx_xfer(struct osmo_ss7_asp *asp, struct xua_msg *xua)
 {
    struct xua_msg_part *na_ie = xua_msg_find_tag(xua, M3UA_IEI_NET_APPEAR);
@@ -594,7 +595,8 @@
    		"%s(): unsupported message type: %s\n",
    		__func__,
    		get_value_string(m3ua_xfer_msgt_names, xua->hdr.msg_type));
-		return M3UA_ERR_UNSUPP_MSG_TYPE;
+		rc = M3UA_ERR_UNSUPP_MSG_TYPE;
+		goto ret_free;
    }
/* Reject unsupported Network Appearance IE. */
@@ -605,13 +607,15 @@
    		"Unsupported 'Network Appearance' IE '0x%08x' in message type '%s', sending 'Error'.\n",
    		na, get_value_string(m3ua_xfer_msgt_names, xua->hdr.msg_type));
    	if (na_ie->len != 4)
-			return M3UA_ERR_PARAM_FIELD_ERR;
-		return M3UA_ERR_INVAL_NET_APPEAR;
+			rc = M3UA_ERR_PARAM_FIELD_ERR;
+		else
+			rc = M3UA_ERR_INVAL_NET_APPEAR;
+		goto ret_free;
    }
rc = xua_find_as_for_asp(&as, asp, rctx_ie);
    if (rc)
-		return rc;
+		goto ret_free;
rate_ctr_inc2(as->ctrg, SS7_AS_CTR_RX_MSU_TOTAL);
@@ -635,8 +639,12 @@
    	xua_msg_free_tag(xua, M3UA_IEI_ROUTE_CTX);
    }
+	/* xua ownership is passed here: */
    return m3ua_hmdc_rx_from_l2(asp->inst, xua);
-	/* xua will be freed by caller m3ua_rx_msg() */
+
+ret_free:
+	xua_msg_free(xua);
+	return rc;
 }
static int m3ua_rx_mgmt_err(struct osmo_ss7_asp *asp, struct xua_msg *xua)
@@ -683,16 +691,24 @@
    return 0;
 }
+/* This function takes ownership of xua msg passed to it. */
 static int m3ua_rx_mgmt(struct osmo_ss7_asp *asp, struct xua_msg *xua)
 {
+	int rc;
+
    switch (xua->hdr.msg_type) {
    case M3UA_MGMT_ERR:
-		return m3ua_rx_mgmt_err(asp, xua);
+		rc = m3ua_rx_mgmt_err(asp, xua);
+		break;
    case M3UA_MGMT_NTFY:
-		return m3ua_rx_mgmt_ntfy(asp, xua);
+		rc = m3ua_rx_mgmt_ntfy(asp, xua);
+		break;
    default:
-		return M3UA_ERR_UNSUPP_MSG_TYPE;
+		rc = M3UA_ERR_UNSUPP_MSG_TYPE;
    }
+
+	xua_msg_free(xua);
+	return rc;
 }
/* map from M3UA ASPSM/ASPTM to xua_asp_fsm event */
@@ -709,23 +725,26 @@
    { M3UA_MSGC_ASPTM, M3UA_ASPTM_INACTIVE_ACK, XUA_ASP_E_ASPTM_ASPIA_ACK },
 };
-
+/* This function takes ownership of xua msg passed to it. */
 static int m3ua_rx_asp(struct osmo_ss7_asp *asp, struct xua_msg *xua)
 {
    int event;
+	int rc = 0;
/* map from the M3UA message class and message type to the XUA
     * ASP FSM event number */
    event = xua_msg_event_map(xua, m3ua_aspxm_map,
    			  ARRAY_SIZE(m3ua_aspxm_map));
-	if (event < 0)
-		return M3UA_ERR_UNSUPP_MSG_TYPE;
+	if (event < 0) {
+		rc = M3UA_ERR_UNSUPP_MSG_TYPE;
+		goto ret_free;
+	}
/* deliver that event to the ASP FSM */
-	if (osmo_fsm_inst_dispatch(asp->fi, event, xua) < 0)
-		return M3UA_ERR_UNEXPECTED_MSG;
-
-	return 0;
+	rc = osmo_fsm_inst_dispatch(asp->fi, event, xua);
+ret_free:
+	xua_msg_free(xua);
+	return rc;
 }
static int m3ua_rx_snm(struct osmo_ss7_asp *asp, struct xua_msg *xua);
@@ -753,9 +772,9 @@
    		"M3UA message\n");
if (hdr->version != M3UA_VERSION)
-			err = m3ua_gen_error_msg(M3UA_ERR_INVALID_VERSION, msg);
+			rc = M3UA_ERR_INVALID_VERSION;
    	else
-			err = m3ua_gen_error_msg(M3UA_ERR_PARAM_FIELD_ERR, msg);
+			rc = M3UA_ERR_PARAM_FIELD_ERR;
    	goto out;
    }
@@ -763,7 +782,8 @@
    	xua_hdr_dump(xua, &xua_dialect_m3ua));
if (!xua_dialect_check_all_mand_ies(&xua_dialect_m3ua, xua)) {
-		err = m3ua_gen_error_msg(M3UA_ERR_MISSING_PARAM, msg);
+		rc = M3UA_ERR_MISSING_PARAM;
+		xua_msg_free(xua);
    	goto out;
    }
@@ -775,7 +795,8 @@
    	/* The DATA message MUST NOT be sent on stream 0. */
    	if (msgb_sctp_stream(msg) == 0) {
    		rc = M3UA_ERR_INVAL_STREAM_ID;
-			break;
+			xua_msg_free(xua);
+			goto out;
    	}
    	rc = m3ua_rx_xfer(asp, xua);
    	break;
@@ -795,19 +816,16 @@
    default:
    	LOGPASP(asp, DLM3UA, LOGL_NOTICE, "Received unknown M3UA "
    		"Message Class %u\n", xua->hdr.msg_class);
-		err = m3ua_gen_error_msg(M3UA_ERR_UNSUPP_MSG_CLASS, msg);
-		break;
+		rc = M3UA_ERR_UNSUPP_MSG_CLASS;
+		xua_msg_free(xua);
+		goto out;
    }
+out:
    if (rc > 0)
    	err = m3ua_gen_error_msg(rc, msg);
-
-out:
    if (err)
    	m3ua_tx_xua_asp(asp, err);
-
-	xua_msg_free(xua);
-
    return rc;
 }
@@ -957,7 +975,8 @@
    m3ua_tx_xua_asp(asp, xua);
 }
-/* received SNM message on ASP side */
+/* received SNM message on ASP side
+ * This function takes ownership of xua msg passed to it. */
 static int m3ua_rx_snm_asp(struct osmo_ss7_asp *asp, struct xua_msg *xua)
 {
    struct osmo_ss7_as *as = NULL;
@@ -966,7 +985,7 @@
rc = xua_find_as_for_asp(&as, asp, rctx_ie);
    if (rc)
-		return rc;
+		goto ret_free;
/* report those up the stack so both other ASPs and local SCCP users can be notified */
    switch (xua->hdr.msg_type) {
@@ -996,14 +1015,16 @@
    		xua_snm_rx_daud(asp, xua);
    	} else {
    		LOGPASP(asp, DLM3UA, LOGL_ERROR, "DAUD not permitted in ASP role\n");
-			return M3UA_ERR_UNSUPP_MSG_TYPE;
+			rc = M3UA_ERR_UNSUPP_MSG_TYPE;
    	}
    	break;
    default:
-		return M3UA_ERR_UNSUPP_MSG_TYPE;
+		rc = M3UA_ERR_UNSUPP_MSG_TYPE;
    }
-	return 0;
+ret_free:
+	xua_msg_free(xua);
+	return rc;
 }
/* received SNM message on SG side */
diff --git a/src/xua_rkm.c b/src/xua_rkm.c
index 8fa8c3b..1ae5ea6 100644
--- a/src/xua_rkm.c
+++ b/src/xua_rkm.c
@@ -548,7 +548,8 @@
    return 0;
 }
-/* process an incoming RKM message in xua format */
+/* process an incoming RKM message in xua format
+ * This function takes ownership of xua msg passed to it. */
 int m3ua_rx_rkm(struct osmo_ss7_asp *asp, struct xua_msg *xua)
 {
    int rc;
@@ -578,6 +579,8 @@
    	rc = -1;
    	break;
    }
+
+	xua_msg_free(xua);
    return rc;
 }
-- 
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Gerrit-MessageType: merged
Gerrit-Project: libosmo-sigtran
Gerrit-Branch: master
Gerrit-Change-Id: Icf3b4dda550637f722a9fe56d0313f49c8a2964e
Gerrit-Change-Number: 39397
Gerrit-PatchSet: 12
Gerrit-Owner: pespin pespin@sysmocom.de
Gerrit-Reviewer: Jenkins Builder
Gerrit-Reviewer: laforge laforge@osmocom.org
Gerrit-Reviewer: osmith osmith@sysmocom.de
Gerrit-Reviewer: pespin pespin@sysmocom.de



    