[dpdk-stable] patch 'service: fix core mapping reset' has been queued to stable release 19.11.4

[luca.boccassi at gmail.com]

Hi,

FYI, your patch has been queued to stable release 19.11.4

Note it hasn't been pushed to http://dpdk.org/browse/dpdk-stable yet.
It will be pushed if I get no objections before 07/26/20. So please
shout if anyone has objections.

Also note that after the patch there's a diff of the upstream commit vs the
patch applied to the branch. This will indicate if there was any rebasing
needed to apply to the stable branch. If there were code changes for rebasing
(ie: not only metadata diffs), please double check that the rebase was
correctly done.

Thanks.

Luca Boccassi

---
>From cc8b7af31f74854edcb7124f56d976487bab7ed9 Mon Sep 17 00:00:00 2001
From: Lukasz Wojciechowski <l.wojciechow at partner.samsung.com>
Date: Wed, 8 Jul 2020 15:37:33 +0200
Subject: [PATCH] service: fix core mapping reset

[ upstream commit 048db4b6dcccaee9277ce5b4fbb2fe684b212e22 ]

The rte_service_lcore_reset_all function stops execution of services
on all lcores and switches them back from ROLE_SERVICE to ROLE_RTE.
However the thread loop for slave lcores (eal_thread_loop) distincts these
roles to set lcore state after processing delegated function.
It sets WAIT state for ROLE_SERVICE, but FINISHED for ROLE_RTE.
So changing the role to RTE before stopping work in slave lcores
causes lcores to end in FINISHED state. That is why the rte_eal_lcore_wait
must be run after rte_service_lcore_reset_all to bring back lcores to
launchable (WAIT) state.
This has been fixed in test app and clarified in API documentation.

Setting the state to WAIT in rte_service_runner_func is premature
as the rte_service_runner_func function is still a part of the lcore
function delegated to slave lcore. The state is overwritten anyway in
slave lcore thread loop. This premature setting state to WAIT might
however cause rte_eal_lcore_wait, that was called by the application,
to return before slave lcore thread set the FINISHED state. That's
why it is removed from librte_eal rte_service_runner_func function.

Bugzilla ID: 464
Fixes: 21698354c832 ("service: introduce service cores concept")
Fixes: f038a81e1c56 ("service: add unit tests")

Reported-by: Sarosh Arif <sarosh.arif at emumba.com>
Signed-off-by: Lukasz Wojciechowski <l.wojciechow at partner.samsung.com>
Acked-by: Harry van Haaren <harry.van.haaren at intel.com>
---
 app/test/test_service_cores.c               | 1 +
 lib/librte_eal/common/include/rte_service.h | 4 ++++
 lib/librte_eal/common/rte_service.c         | 2 --
 3 files changed, 5 insertions(+), 2 deletions(-)

diff --git a/app/test/test_service_cores.c b/app/test/test_service_cores.c
index a922c7ddc..2a4978e29 100644
--- a/app/test/test_service_cores.c
+++ b/app/test/test_service_cores.c
@@ -114,6 +114,7 @@ unregister_all(void)
 	}
 
 	rte_service_lcore_reset_all();
+	rte_eal_mp_wait_lcore();
 
 	return TEST_SUCCESS;
 }
diff --git a/lib/librte_eal/common/include/rte_service.h b/lib/librte_eal/common/include/rte_service.h
index 3a1c735c5..e2d0a6dd3 100644
--- a/lib/librte_eal/common/include/rte_service.h
+++ b/lib/librte_eal/common/include/rte_service.h
@@ -304,6 +304,10 @@ int32_t rte_service_lcore_count(void);
  * from duty, just unmaps all services / cores, and stops() the service cores.
  * The runstate of services is not modified.
  *
+ * The cores that are stopped with this call, are in FINISHED state and
+ * the application must take care of bringing them back to a launchable state:
+ * e.g. call *rte_eal_lcore_wait* on the lcore_id.
+ *
  * @retval 0 Success
  */
 int32_t rte_service_lcore_reset_all(void);
diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
index eca6ccc59..8fcccac85 100644
--- a/lib/librte_eal/common/rte_service.c
+++ b/lib/librte_eal/common/rte_service.c
@@ -447,8 +447,6 @@ service_runner_func(void *arg)
 		rte_smp_rmb();
 	}
 
-	lcore_config[lcore].state = WAIT;
-
 	return 0;
 }
 
-- 
2.20.1

---
  Diff of the applied patch vs upstream commit (please double-check if non-empty:
---
--- -	2020-07-24 12:53:52.548982028 +0100
+++ 0104-service-fix-core-mapping-reset.patch	2020-07-24 12:53:48.347007578 +0100
@@ -1,8 +1,10 @@
-From 048db4b6dcccaee9277ce5b4fbb2fe684b212e22 Mon Sep 17 00:00:00 2001
+From cc8b7af31f74854edcb7124f56d976487bab7ed9 Mon Sep 17 00:00:00 2001
 From: Lukasz Wojciechowski <l.wojciechow at partner.samsung.com>
 Date: Wed, 8 Jul 2020 15:37:33 +0200
 Subject: [PATCH] service: fix core mapping reset
 
+[ upstream commit 048db4b6dcccaee9277ce5b4fbb2fe684b212e22 ]
+
 The rte_service_lcore_reset_all function stops execution of services
 on all lcores and switches them back from ROLE_SERVICE to ROLE_RTE.
 However the thread loop for slave lcores (eal_thread_loop) distincts these
@@ -25,19 +27,18 @@
 Bugzilla ID: 464
 Fixes: 21698354c832 ("service: introduce service cores concept")
 Fixes: f038a81e1c56 ("service: add unit tests")
-Cc: stable at dpdk.org
 
 Reported-by: Sarosh Arif <sarosh.arif at emumba.com>
 Signed-off-by: Lukasz Wojciechowski <l.wojciechow at partner.samsung.com>
 Acked-by: Harry van Haaren <harry.van.haaren at intel.com>
 ---
- app/test/test_service_cores.c        | 1 +
- lib/librte_eal/common/rte_service.c  | 2 --
- lib/librte_eal/include/rte_service.h | 4 ++++
+ app/test/test_service_cores.c               | 1 +
+ lib/librte_eal/common/include/rte_service.h | 4 ++++
+ lib/librte_eal/common/rte_service.c         | 2 --
  3 files changed, 5 insertions(+), 2 deletions(-)
 
 diff --git a/app/test/test_service_cores.c b/app/test/test_service_cores.c
-index 4f003ed1a..ef1d8fcb9 100644
+index a922c7ddc..2a4978e29 100644
 --- a/app/test/test_service_cores.c
 +++ b/app/test/test_service_cores.c
 @@ -114,6 +114,7 @@ unregister_all(void)
@@ -48,23 +49,10 @@
  
  	return TEST_SUCCESS;
  }
-diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
-index e2795f857..6a0e0ff65 100644
---- a/lib/librte_eal/common/rte_service.c
-+++ b/lib/librte_eal/common/rte_service.c
-@@ -475,8 +475,6 @@ service_runner_func(void *arg)
- 		cs->loops++;
- 	}
- 
--	lcore_config[lcore].state = WAIT;
--
- 	return 0;
- }
- 
-diff --git a/lib/librte_eal/include/rte_service.h b/lib/librte_eal/include/rte_service.h
+diff --git a/lib/librte_eal/common/include/rte_service.h b/lib/librte_eal/common/include/rte_service.h
 index 3a1c735c5..e2d0a6dd3 100644
---- a/lib/librte_eal/include/rte_service.h
-+++ b/lib/librte_eal/include/rte_service.h
+--- a/lib/librte_eal/common/include/rte_service.h
++++ b/lib/librte_eal/common/include/rte_service.h
 @@ -304,6 +304,10 @@ int32_t rte_service_lcore_count(void);
   * from duty, just unmaps all services / cores, and stops() the service cores.
   * The runstate of services is not modified.
@@ -76,6 +64,19 @@
   * @retval 0 Success
   */
  int32_t rte_service_lcore_reset_all(void);
+diff --git a/lib/librte_eal/common/rte_service.c b/lib/librte_eal/common/rte_service.c
+index eca6ccc59..8fcccac85 100644
+--- a/lib/librte_eal/common/rte_service.c
++++ b/lib/librte_eal/common/rte_service.c
+@@ -447,8 +447,6 @@ service_runner_func(void *arg)
+ 		rte_smp_rmb();
+ 	}
+ 
+-	lcore_config[lcore].state = WAIT;
+-
+ 	return 0;
+ }
+ 
 -- 
 2.20.1