starlingx/integ
Code Issues Proposed changes
integ/base/linuxptp/debian/patches/0020-pmc_agent-Convert-the-subscribe-method-into-the-cano.patch
Cole Walker aca42c6d4c Implement logic to skip updates with offset spike in ts2phc. 
This change allows ts2phc to be configured to ignore timing updates that
have a large offset spike in order to mitigate the resulting timing
skew.

In some circumstances on realtime systems with high CPU load, the
timestamp consumed by ts2phc can be delayed in reaching ts2phc and
results in the offset calculation attempting to speed the clock up by a
large margin.

This change causes ts2phc to ignore updates that would greatly skew the
clock when ts2phc is already in a synchronized state.

The global configuration option "max_phc_update_skip_cnt" is provided to
allow users to specify how many consecutive offset spike incidents will
be ignored before adjusting the clock. The default value is 120. The
behaviour can be disabled by setting max_phc_update_skip_cnt to 0.

This code is ported from a proposed upstream patch found here:
https://sourceforge.net/p/linuxptp/mailman/message/44114092/

Test-plan:
Pass: Verify linuxptp package build
Pass: Deploy ts2phc binary and verify system time sync
Pass: Manually trigger offset spike and verify that ts2phc maintains
stable time sync

Closes-bug: https://bugs.launchpad.net/starlingx/+bug/2059955

Change-Id: I13cd5c3440682ec9256e11449fe62d5fe28f66fa
Signed-off-by: Cole Walker <cole.walker@windriver.com>
2024-04-01 14:53:06 -04:00

154 lines
4.6 KiB
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Raw Blame History

From 479301925d24906f03b13821ee8bd6cafb58c8c5 Mon Sep 17 00:00:00 2001
From: Andre Mauricio Zelak <andre.zelak@windriver.com>
Date: Mon, 12 Jun 2023 15:08:01 -0300
Subject: [PATCH 20/58] pmc_agent: Convert the subscribe method into the
canonical form.
This patch renames the function to have the module prefix and corrects the
return code semantics.
Signed-off-by: Richard Cochran <richardcochran@gmail.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Reviewed-by: Vladimir Oltean <olteanv@gmail.com>
[commit cc98d39f58adc1fd05db0038acfdcc5669f2ba8c upstream]
Signed-off-by: Andre Mauricio Zelak <andre.zelak@windriver.com>
---
phc2sys.c | 4 ++--
pmc_agent.c | 48 +++++++++++++++++++++++++++++++++++-------------
pmc_agent.h | 9 ++++++++-
3 files changed, 45 insertions(+), 16 deletions(-)
diff --git a/phc2sys.c b/phc2sys.c
index 280e249..f61e699 100644
--- a/phc2sys.c
+++ b/phc2sys.c
@@ -875,8 +875,8 @@ static int auto_init_ports(struct phc2sys_private *priv, int add_rt)
return -1;
}
- res = run_pmc_subscribe(priv->node, 1000);
- if (res <= 0) {
+ res = pmc_agent_subscribe(priv->node, 1000);
+ if (res) {
pr_err("failed to subscribe");
return -1;
}
diff --git a/pmc_agent.c b/pmc_agent.c
index 22d9c5b..9c5eb71 100644
--- a/pmc_agent.c
+++ b/pmc_agent.c
@@ -17,6 +17,7 @@
* with this program; if not, write to the Free Software Foundation, Inc.,
* 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
+#include <errno.h>
#include <net/if.h>
#include <poll.h>
#include <stdlib.h>
@@ -98,6 +99,26 @@ static int get_mgt_err_id(struct ptp_message *msg)
#define RUN_PMC_NODEV -1
#define RUN_PMC_INTR -2
+static bool is_run_pmc_error(int code)
+{
+ return code != RUN_PMC_OKAY;
+}
+
+static int run_pmc_err2errno(int code)
+{
+ switch (code) {
+ case RUN_PMC_TMO:
+ return -ETIMEDOUT;
+ case RUN_PMC_NODEV:
+ return -ENODEV;
+ case RUN_PMC_INTR:
+ return -EINTR;
+ case RUN_PMC_OKAY:
+ default:
+ return 0;
+ }
+}
+
static int run_pmc(struct pmc_agent *node, int timeout, int ds_id,
struct ptp_message **msg)
{
@@ -239,18 +260,6 @@ int run_pmc_get_number_ports(struct pmc_agent *node, int timeout)
return res;
}
-int run_pmc_subscribe(struct pmc_agent *node, int timeout)
-{
- struct ptp_message *msg;
- int res;
-
- res = run_pmc(node, timeout, TLV_SUBSCRIBE_EVENTS_NP, &msg);
- if (res <= 0)
- return res;
- msg_put(msg);
- return 1;
-}
-
void run_pmc_events(struct pmc_agent *node)
{
struct ptp_message *msg;
@@ -329,7 +338,7 @@ int update_pmc_node(struct pmc_agent *node, int subscribe)
!(ts > node->pmc_last_update &&
ts - node->pmc_last_update < PMC_UPDATE_INTERVAL)) {
if (subscribe)
- run_pmc_subscribe(node, 0);
+ pmc_agent_subscribe(node, 0);
if (run_pmc_get_utc_offset(node, 0) > 0)
node->pmc_last_update = ts;
}
@@ -382,6 +391,19 @@ void pmc_agent_set_sync_offset(struct pmc_agent *agent, int offset)
agent->sync_offset = offset;
}
+int pmc_agent_subscribe(struct pmc_agent *node, int timeout)
+{
+ struct ptp_message *msg;
+ int res;
+
+ res = run_pmc(node, timeout, TLV_SUBSCRIBE_EVENTS_NP, &msg);
+ if (is_run_pmc_error(res)) {
+ return run_pmc_err2errno(res);
+ }
+ msg_put(msg);
+ return 0;
+}
+
bool pmc_agent_utc_offset_traceable(struct pmc_agent *agent)
{
return agent->utc_offset_traceable;
diff --git a/pmc_agent.h b/pmc_agent.h
index f3a26fe..9dc684e 100644
--- a/pmc_agent.h
+++ b/pmc_agent.h
@@ -34,7 +34,6 @@ typedef int pmc_node_recv_subscribed_t(void *context, struct ptp_message *msg,
int init_pmc_node(struct config *cfg, struct pmc_agent *agent, const char *uds,
pmc_node_recv_subscribed_t *recv_subscribed, void *context);
int update_pmc_node(struct pmc_agent *agent, int subscribe);
-int run_pmc_subscribe(struct pmc_agent *agent, int timeout);
int run_pmc_clock_identity(struct pmc_agent *agent, int timeout);
int run_pmc_wait_sync(struct pmc_agent *agent, int timeout);
int run_pmc_get_number_ports(struct pmc_agent *agent, int timeout);
@@ -78,6 +77,14 @@ int pmc_agent_get_sync_offset(struct pmc_agent *agent);
*/
void pmc_agent_set_sync_offset(struct pmc_agent *agent, int offset);
+/**
+ * Subscribes to push notifications of changes in port state.
+ * @param agent Pointer to a PMC instance obtained via @ref pmc_agent_create().
+ * @param timeout Transmit and receive timeout in milliseconds.
+ * @return Zero on success, negative error code otherwise.
+ */
+int pmc_agent_subscribe(struct pmc_agent *agent, int timeout);
+
/**
* Tests whether the current UTC offset is traceable.
* @param agent Pointer to a PMC instance obtained via @ref pmc_agent_create().
--
2.30.2
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