[dpdk-dev] [PATCH v1 0/1] Add service lcore attributes API

[dpdk-dev] [PATCH v1 0/1] Add service lcore attributes API

[Erik Gabriel Carrillo]

This patch proposes the addition of an API which allows an application to
query the attributes of a service lcore.  It adds one such new attribute,
named "loops", which is a counter that tracks the number of times the service
core has looped in the service runner function (the driver function that
invokes services mapped to a service core).  This is useful to applications
that desire a "liveness" check to make sure a service core is not stuck.

Erik Gabriel Carrillo (1):
  service: Add service lcore attr APIs

 lib/librte_eal/common/include/rte_service.h | 30 ++++++++++++
 lib/librte_eal/common/rte_service.c         | 43 ++++++++++++++++-
 lib/librte_eal/rte_eal_version.map          |  2 +
 test/test/test_service_cores.c              | 73 +++++++++++++++++++++++++++++
 4 files changed, 147 insertions(+), 1 deletion(-)

-- 
2.6.4

[dpdk-dev] [PATCH v1 1/1] service: Add service lcore attr APIs

[Erik Gabriel Carrillo]

Add a counter that gets bumped each time the service runner loop goes
around, and APIs to query and reset the attribute values.

Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
---
 lib/librte_eal/common/include/rte_service.h | 30 ++++++++++++
 lib/librte_eal/common/rte_service.c         | 43 ++++++++++++++++-
 lib/librte_eal/rte_eal_version.map          |  2 +
 test/test/test_service_cores.c              | 73 +++++++++++++++++++++++++++++
 4 files changed, 147 insertions(+), 1 deletion(-)

diff --git a/lib/librte_eal/common/include/rte_service.h b/lib/librte_eal/common/include/rte_service.h
index aea4d91..05d51a2 100644
--- a/lib/librte_eal/common/include/rte_service.h
+++ b/lib/librte_eal/common/include/rte_service.h
@@ -363,6 +363,36 @@ int32_t rte_service_attr_get(uint32_t id, uint32_t attr_id,
  */
 int32_t rte_service_attr_reset_all(uint32_t id);
 
+/**
+ * Returns the number of times the service runner has looped.
+ */
+#define RTE_SERVICE_LCORE_ATTR_LOOPS 0
+
+/**
+ * Get an attribute from a service core.
+ *
+ * @param lcore Id of the service core.
+ * @param attr_id Id of the attribute to be retrieved.
+ * @param [out] attr_value Pointer to storage in which to write retrieved value.
+ * @retval 0 Success, the attribute value has been written to *attr_value*.
+ *         -EINVAL Invalid lcore, attr_id or attr_value was NULL.
+ *         -ENOTSUP lcore is not a service core.
+ */
+int32_t __rte_experimental
+rte_service_lcore_attr_get(uint32_t lcore, uint32_t attr_id,
+			   uint64_t *attr_value);
+
+/**
+ * Reset all attribute values of a service core.
+ *
+ * @param lcore The service core to reset all the statistics of
+ * @retval 0 Successfully reset attributes
+ *         -EINVAL Invalid service id provided
+ *         -ENOTSUP lcore is not a service core.
+ */
+int32_t __rte_experimental
+rte_service_lcore_attr_reset_all(uint32_t lcore);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
index 73507aa..fa15f66 100644
--- a/lib/librte_eal/common/rte_service.c
+++ b/lib/librte_eal/common/rte_service.c
@@ -61,7 +61,7 @@ struct core_state {
 	uint8_t runstate; /* running or stopped */
 	uint8_t is_service_core; /* set if core is currently a service core */
 
-	/* extreme statistics */
+	uint64_t loops;
 	uint64_t calls_per_service[RTE_SERVICE_NUM_MAX];
 } __rte_cache_aligned;
 
@@ -422,6 +422,8 @@ rte_service_runner_func(void *arg)
 			service_run(i, cs, service_mask);
 		}
 
+		cs->loops++;
+
 		rte_smp_rmb();
 	}
 
@@ -729,6 +731,28 @@ rte_service_attr_get(uint32_t id, uint32_t attr_id, uint32_t *attr_value)
 	}
 }
 
+int32_t __rte_experimental
+rte_service_lcore_attr_get(uint32_t lcore, uint32_t attr_id,
+			   uint64_t *attr_value)
+{
+	struct core_state *cs;
+
+	if (lcore >= RTE_MAX_LCORE || !attr_value)
+		return -EINVAL;
+
+	cs = &lcore_states[lcore];
+	if (!cs->is_service_core)
+		return -ENOTSUP;
+
+	switch (attr_id) {
+	case RTE_SERVICE_LCORE_ATTR_LOOPS:
+		*attr_value = cs->loops;
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
 static void
 rte_service_dump_one(FILE *f, struct rte_service_spec_impl *s,
 		     uint64_t all_cycles, uint32_t reset)
@@ -764,6 +788,23 @@ rte_service_attr_reset_all(uint32_t id)
 	return 0;
 }
 
+int32_t __rte_experimental
+rte_service_lcore_attr_reset_all(uint32_t lcore)
+{
+	struct core_state *cs;
+
+	if (lcore >= RTE_MAX_LCORE)
+		return -EINVAL;
+
+	cs = &lcore_states[lcore];
+	if (!cs->is_service_core)
+		return -ENOTSUP;
+
+	cs->loops = 0;
+
+	return 0;
+}
+
 static void
 service_dump_calls_per_lcore(FILE *f, uint32_t lcore, uint32_t reset)
 {
diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index 8597239..5af7233 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -297,6 +297,8 @@ EXPERIMENTAL {
 	rte_mp_request_sync;
 	rte_mp_request_async;
 	rte_mp_sendmsg;
+	rte_service_lcore_attr_get;
+	rte_service_lcore_attr_reset_all;
 	rte_socket_count;
 	rte_socket_id_by_idx;
 	rte_vfio_dma_map;
diff --git a/test/test/test_service_cores.c b/test/test/test_service_cores.c
index 86b4073..9f21d59 100644
--- a/test/test/test_service_cores.c
+++ b/test/test/test_service_cores.c
@@ -325,6 +325,78 @@ service_attr_get(void)
 	return unregister_all();
 }
 
+/* verify service lcore attr get */
+static int
+service_lcore_attr_get(void)
+{
+	/* ensure all services unregistered so cycle counts are zero */
+	unregister_all();
+
+	struct rte_service_spec service;
+	memset(&service, 0, sizeof(struct rte_service_spec));
+	service.callback = dummy_cb;
+	snprintf(service.name, sizeof(service.name), DUMMY_SERVICE_NAME);
+	service.capabilities |= RTE_SERVICE_CAP_MT_SAFE;
+	uint32_t id;
+	TEST_ASSERT_EQUAL(0, rte_service_component_register(&service, &id),
+			"Register of  service failed");
+	rte_service_component_runstate_set(id, 1);
+	TEST_ASSERT_EQUAL(0, rte_service_runstate_set(id, 1),
+			"Error: Service start returned non-zero");
+	rte_service_set_stats_enable(id, 1);
+
+	uint64_t lcore_attr_value = 0xdead;
+	uint32_t lcore_attr_id = UINT32_MAX;
+
+	/* check error return values */
+	TEST_ASSERT_EQUAL(-EINVAL, rte_service_lcore_attr_get(UINT32_MAX,
+			lcore_attr_id, &lcore_attr_value),
+			"Invalid lcore_id didn't return -EINVAL");
+	TEST_ASSERT_EQUAL(-ENOTSUP, rte_service_lcore_attr_get(rte_lcore_id(),
+			lcore_attr_id, &lcore_attr_value),
+			"Non-service core didn't return -ENOTSUP");
+
+	/* Start service core to increment loop count */
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_add(slcore_id),
+			"Service core add did not return zero");
+	TEST_ASSERT_EQUAL(0, rte_service_map_lcore_set(id, slcore_id, 1),
+			"Enabling valid service and core failed");
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_start(slcore_id),
+			"Starting service core failed");
+
+	/* wait for the service lcore to run */
+	rte_delay_ms(200);
+
+	lcore_attr_id = RTE_SERVICE_LCORE_ATTR_LOOPS;
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_attr_get(slcore_id,
+			lcore_attr_id, &lcore_attr_value),
+			"Valid lcore_attr_get() call didn't return success");
+	int loops_gt_zero = lcore_attr_value > 0;
+	TEST_ASSERT_EQUAL(1, loops_gt_zero,
+			"lcore_attr_get() failed to get loops "
+			"(expected > zero)");
+
+	lcore_attr_id++;  // invalid lcore attr id
+	TEST_ASSERT_EQUAL(-EINVAL, rte_service_lcore_attr_get(slcore_id,
+			lcore_attr_id, &lcore_attr_value),
+			"Invalid lcore attr didn't return -EINVAL");
+
+	rte_service_lcore_stop(slcore_id);
+
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_attr_reset_all(slcore_id),
+			  "Valid lcore_attr_reset_all() didn't return success");
+
+	lcore_attr_id = RTE_SERVICE_LCORE_ATTR_LOOPS;
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_attr_get(slcore_id,
+			lcore_attr_id, &lcore_attr_value),
+			"Valid lcore_attr_get() call didn't return success");
+	TEST_ASSERT_EQUAL(0, lcore_attr_value,
+			"lcore_attr_get() didn't get correct loop count "
+			"(zero)");
+
+	return unregister_all();
+}
+
 /* verify service dump */
 static int
 service_dump(void)
@@ -781,6 +853,7 @@ static struct unit_test_suite service_tests  = {
 		TEST_CASE_ST(dummy_register, NULL, service_get_by_name),
 		TEST_CASE_ST(dummy_register, NULL, service_dump),
 		TEST_CASE_ST(dummy_register, NULL, service_attr_get),
+		TEST_CASE_ST(dummy_register, NULL, service_lcore_attr_get),
 		TEST_CASE_ST(dummy_register, NULL, service_probe_capability),
 		TEST_CASE_ST(dummy_register, NULL, service_start_stop),
 		TEST_CASE_ST(dummy_register, NULL, service_lcore_add_del),
-- 
2.6.4

Re: [dpdk-dev] [PATCH v1 1/1] service: Add service lcore attr APIs

[Van Haaren, Harry]

> -----Original Message-----
> From: Carrillo, Erik G
> Sent: Friday, May 4, 2018 9:16 PM
> To: Van Haaren, Harry <harry.van.haaren@intel.com>
> Cc: jerin.jacob@caviumnetworks.com; Vangati, Narender
> <narender.vangati@intel.com>; Eads, Gage <gage.eads@intel.com>; dev@dpdk.org
> Subject: [PATCH v1 1/1] service: Add service lcore attr APIs
> 
> Add a counter that gets bumped each time the service runner loop goes
> around, and APIs to query and reset the attribute values.
> 
> Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>

>From cover letter for this patch:

This patch proposes the addition of an API which allows an application to
query the attributes of a service lcore.  It adds one such new attribute,
named "loops", which is a counter that tracks the number of times the service
core has looped in the service runner function (the driver function that
invokes services mapped to a service core).  This is useful to applications
that desire a "liveness" check to make sure a service core is not stuck.


When sending a single patch it is not required to send with --cover-letter.

I like the description provided in the cover letter, perhaps merge the
current commit message with the cover-letter paragraph?

For the v2, please include

Acked-by: Harry van Haaren <harry.van.haaren@intel.com>

Re: [dpdk-dev] [PATCH v1 1/1] service: Add service lcore attr APIs

[Carrillo, Erik G]

> -----Original Message-----
> From: Van Haaren, Harry
> Sent: Wednesday, May 9, 2018 10:19 AM
> To: Carrillo, Erik G <erik.g.carrillo@intel.com>
> Cc: jerin.jacob@caviumnetworks.com; Vangati, Narender
> <narender.vangati@intel.com>; Eads, Gage <gage.eads@intel.com>;
> dev@dpdk.org
> Subject: RE: [PATCH v1 1/1] service: Add service lcore attr APIs
> 
> > -----Original Message-----
> > From: Carrillo, Erik G
> > Sent: Friday, May 4, 2018 9:16 PM
> > To: Van Haaren, Harry <harry.van.haaren@intel.com>
> > Cc: jerin.jacob@caviumnetworks.com; Vangati, Narender
> > <narender.vangati@intel.com>; Eads, Gage <gage.eads@intel.com>;
> > dev@dpdk.org
> > Subject: [PATCH v1 1/1] service: Add service lcore attr APIs
> >
> > Add a counter that gets bumped each time the service runner loop goes
> > around, and APIs to query and reset the attribute values.
> >
> > Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
> 
> From cover letter for this patch:
> 
> This patch proposes the addition of an API which allows an application to
> query the attributes of a service lcore.  It adds one such new attribute,
> named "loops", which is a counter that tracks the number of times the
> service core has looped in the service runner function (the driver function
> that invokes services mapped to a service core).  This is useful to applications
> that desire a "liveness" check to make sure a service core is not stuck.
> 
> 
> When sending a single patch it is not required to send with --cover-letter.
> 
> I like the description provided in the cover letter, perhaps merge the current
> commit message with the cover-letter paragraph?
> 
> For the v2, please include
> 
> Acked-by: Harry van Haaren <harry.van.haaren@intel.com>
> 

Thanks for the review, Harry.  I'll make the changes and resubmit.

[dpdk-dev] [PATCH v2 1/1] service: Add service lcore attr APIs

[Erik Gabriel Carrillo]

Add APIs that allow an application to query and reset the attributes of
a service lcore.  Add one such new attribute, "loops", which is a
counter that tracks the number of times the service core has looped in
the service runner function.  This is useful to applications that desire
a "liveness" check to make sure a service core is not stuck.

Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
Acked-by: Harry van Haaren <harry.van.haaren@intel.com>
---
v2:
 - Update doxygen comments to indicate that APIs are experimental
 - Move cover letter description of patch to commit message (Harry)

 lib/librte_eal/common/include/rte_service.h | 36 ++++++++++++++
 lib/librte_eal/common/rte_service.c         | 43 ++++++++++++++++-
 lib/librte_eal/rte_eal_version.map          |  2 +
 test/test/test_service_cores.c              | 73 +++++++++++++++++++++++++++++
 4 files changed, 153 insertions(+), 1 deletion(-)

diff --git a/lib/librte_eal/common/include/rte_service.h b/lib/librte_eal/common/include/rte_service.h
index aea4d91..ba2c3cd 100644
--- a/lib/librte_eal/common/include/rte_service.h
+++ b/lib/librte_eal/common/include/rte_service.h
@@ -363,6 +363,42 @@ int32_t rte_service_attr_get(uint32_t id, uint32_t attr_id,
  */
 int32_t rte_service_attr_reset_all(uint32_t id);
 
+/**
+ * Returns the number of times the service runner has looped.
+ */
+#define RTE_SERVICE_LCORE_ATTR_LOOPS 0
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Get an attribute from a service core.
+ *
+ * @param lcore Id of the service core.
+ * @param attr_id Id of the attribute to be retrieved.
+ * @param [out] attr_value Pointer to storage in which to write retrieved value.
+ * @retval 0 Success, the attribute value has been written to *attr_value*.
+ *         -EINVAL Invalid lcore, attr_id or attr_value was NULL.
+ *         -ENOTSUP lcore is not a service core.
+ */
+int32_t __rte_experimental
+rte_service_lcore_attr_get(uint32_t lcore, uint32_t attr_id,
+			   uint64_t *attr_value);
+
+/**
+ * @warning
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * Reset all attribute values of a service core.
+ *
+ * @param lcore The service core to reset all the statistics of
+ * @retval 0 Successfully reset attributes
+ *         -EINVAL Invalid service id provided
+ *         -ENOTSUP lcore is not a service core.
+ */
+int32_t __rte_experimental
+rte_service_lcore_attr_reset_all(uint32_t lcore);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
index 73507aa..fa15f66 100644
--- a/lib/librte_eal/common/rte_service.c
+++ b/lib/librte_eal/common/rte_service.c
@@ -61,7 +61,7 @@ struct core_state {
 	uint8_t runstate; /* running or stopped */
 	uint8_t is_service_core; /* set if core is currently a service core */
 
-	/* extreme statistics */
+	uint64_t loops;
 	uint64_t calls_per_service[RTE_SERVICE_NUM_MAX];
 } __rte_cache_aligned;
 
@@ -422,6 +422,8 @@ rte_service_runner_func(void *arg)
 			service_run(i, cs, service_mask);
 		}
 
+		cs->loops++;
+
 		rte_smp_rmb();
 	}
 
@@ -729,6 +731,28 @@ rte_service_attr_get(uint32_t id, uint32_t attr_id, uint32_t *attr_value)
 	}
 }
 
+int32_t __rte_experimental
+rte_service_lcore_attr_get(uint32_t lcore, uint32_t attr_id,
+			   uint64_t *attr_value)
+{
+	struct core_state *cs;
+
+	if (lcore >= RTE_MAX_LCORE || !attr_value)
+		return -EINVAL;
+
+	cs = &lcore_states[lcore];
+	if (!cs->is_service_core)
+		return -ENOTSUP;
+
+	switch (attr_id) {
+	case RTE_SERVICE_LCORE_ATTR_LOOPS:
+		*attr_value = cs->loops;
+		return 0;
+	default:
+		return -EINVAL;
+	}
+}
+
 static void
 rte_service_dump_one(FILE *f, struct rte_service_spec_impl *s,
 		     uint64_t all_cycles, uint32_t reset)
@@ -764,6 +788,23 @@ rte_service_attr_reset_all(uint32_t id)
 	return 0;
 }
 
+int32_t __rte_experimental
+rte_service_lcore_attr_reset_all(uint32_t lcore)
+{
+	struct core_state *cs;
+
+	if (lcore >= RTE_MAX_LCORE)
+		return -EINVAL;
+
+	cs = &lcore_states[lcore];
+	if (!cs->is_service_core)
+		return -ENOTSUP;
+
+	cs->loops = 0;
+
+	return 0;
+}
+
 static void
 service_dump_calls_per_lcore(FILE *f, uint32_t lcore, uint32_t reset)
 {
diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map
index 8597239..5af7233 100644
--- a/lib/librte_eal/rte_eal_version.map
+++ b/lib/librte_eal/rte_eal_version.map
@@ -297,6 +297,8 @@ EXPERIMENTAL {
 	rte_mp_request_sync;
 	rte_mp_request_async;
 	rte_mp_sendmsg;
+	rte_service_lcore_attr_get;
+	rte_service_lcore_attr_reset_all;
 	rte_socket_count;
 	rte_socket_id_by_idx;
 	rte_vfio_dma_map;
diff --git a/test/test/test_service_cores.c b/test/test/test_service_cores.c
index 86b4073..9f21d59 100644
--- a/test/test/test_service_cores.c
+++ b/test/test/test_service_cores.c
@@ -325,6 +325,78 @@ service_attr_get(void)
 	return unregister_all();
 }
 
+/* verify service lcore attr get */
+static int
+service_lcore_attr_get(void)
+{
+	/* ensure all services unregistered so cycle counts are zero */
+	unregister_all();
+
+	struct rte_service_spec service;
+	memset(&service, 0, sizeof(struct rte_service_spec));
+	service.callback = dummy_cb;
+	snprintf(service.name, sizeof(service.name), DUMMY_SERVICE_NAME);
+	service.capabilities |= RTE_SERVICE_CAP_MT_SAFE;
+	uint32_t id;
+	TEST_ASSERT_EQUAL(0, rte_service_component_register(&service, &id),
+			"Register of  service failed");
+	rte_service_component_runstate_set(id, 1);
+	TEST_ASSERT_EQUAL(0, rte_service_runstate_set(id, 1),
+			"Error: Service start returned non-zero");
+	rte_service_set_stats_enable(id, 1);
+
+	uint64_t lcore_attr_value = 0xdead;
+	uint32_t lcore_attr_id = UINT32_MAX;
+
+	/* check error return values */
+	TEST_ASSERT_EQUAL(-EINVAL, rte_service_lcore_attr_get(UINT32_MAX,
+			lcore_attr_id, &lcore_attr_value),
+			"Invalid lcore_id didn't return -EINVAL");
+	TEST_ASSERT_EQUAL(-ENOTSUP, rte_service_lcore_attr_get(rte_lcore_id(),
+			lcore_attr_id, &lcore_attr_value),
+			"Non-service core didn't return -ENOTSUP");
+
+	/* Start service core to increment loop count */
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_add(slcore_id),
+			"Service core add did not return zero");
+	TEST_ASSERT_EQUAL(0, rte_service_map_lcore_set(id, slcore_id, 1),
+			"Enabling valid service and core failed");
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_start(slcore_id),
+			"Starting service core failed");
+
+	/* wait for the service lcore to run */
+	rte_delay_ms(200);
+
+	lcore_attr_id = RTE_SERVICE_LCORE_ATTR_LOOPS;
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_attr_get(slcore_id,
+			lcore_attr_id, &lcore_attr_value),
+			"Valid lcore_attr_get() call didn't return success");
+	int loops_gt_zero = lcore_attr_value > 0;
+	TEST_ASSERT_EQUAL(1, loops_gt_zero,
+			"lcore_attr_get() failed to get loops "
+			"(expected > zero)");
+
+	lcore_attr_id++;  // invalid lcore attr id
+	TEST_ASSERT_EQUAL(-EINVAL, rte_service_lcore_attr_get(slcore_id,
+			lcore_attr_id, &lcore_attr_value),
+			"Invalid lcore attr didn't return -EINVAL");
+
+	rte_service_lcore_stop(slcore_id);
+
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_attr_reset_all(slcore_id),
+			  "Valid lcore_attr_reset_all() didn't return success");
+
+	lcore_attr_id = RTE_SERVICE_LCORE_ATTR_LOOPS;
+	TEST_ASSERT_EQUAL(0, rte_service_lcore_attr_get(slcore_id,
+			lcore_attr_id, &lcore_attr_value),
+			"Valid lcore_attr_get() call didn't return success");
+	TEST_ASSERT_EQUAL(0, lcore_attr_value,
+			"lcore_attr_get() didn't get correct loop count "
+			"(zero)");
+
+	return unregister_all();
+}
+
 /* verify service dump */
 static int
 service_dump(void)
@@ -781,6 +853,7 @@ static struct unit_test_suite service_tests  = {
 		TEST_CASE_ST(dummy_register, NULL, service_get_by_name),
 		TEST_CASE_ST(dummy_register, NULL, service_dump),
 		TEST_CASE_ST(dummy_register, NULL, service_attr_get),
+		TEST_CASE_ST(dummy_register, NULL, service_lcore_attr_get),
 		TEST_CASE_ST(dummy_register, NULL, service_probe_capability),
 		TEST_CASE_ST(dummy_register, NULL, service_start_stop),
 		TEST_CASE_ST(dummy_register, NULL, service_lcore_add_del),
-- 
2.6.4

Re: [dpdk-dev] [PATCH v2 1/1] service: Add service lcore attr APIs

[Thomas Monjalon]

09/05/2018 18:22, Erik Gabriel Carrillo:
> Add APIs that allow an application to query and reset the attributes of
> a service lcore.  Add one such new attribute, "loops", which is a
> counter that tracks the number of times the service core has looped in
> the service runner function.  This is useful to applications that desire
> a "liveness" check to make sure a service core is not stuck.
> 
> Signed-off-by: Erik Gabriel Carrillo <erik.g.carrillo@intel.com>
> Acked-by: Harry van Haaren <harry.van.haaren@intel.com>

Applied, thanks