From: Luc Pelletier <lucp.at.work@gmail.com>
To: olivier.matz@6wind.com, jianfeng.tan@intel.com,
Honnappa.Nagarahalli@arm.com
Cc: dev@dpdk.org, Luc Pelletier <lucp.at.work@gmail.com>, stable@dpdk.org
Subject: [dpdk-stable] [PATCH 2/2] eal: fix hang in ctrl thread creation error logic
Date: Wed, 7 Apr 2021 16:16:06 -0400 [thread overview]
Message-ID: <20210407201603.149234-2-lucp.at.work@gmail.com> (raw)
In-Reply-To: <DBAPR08MB581490C7F81791C485E062F698759@DBAPR08MB5814.eurprd08.prod.outlook.com>
The affinity of a control thread is set after it has been launched. If
setting the affinity fails, pthread_cancel is called followed by a call
to pthread_join, which can hang forever if the thread's start routine
doesn't call a pthread cancellation point.
This patch modifies the logic so that the control thread exits
gracefully if the affinity cannot be set successfully and removes the
call to pthread_cancel.
Fixes: 6383d26 ("eal: set name when creating a control thread")
Cc: olivier.matz@6wind.com
Cc: stable@dpdk.org
Signed-off-by: Luc Pelletier <lucp.at.work@gmail.com>
---
Hi Olivier,
Hi Honnappa,
As discussed, I've split the changes into 2 patches. This second commit
removes the pthread_cancel call which could result in a hang on join, if
the ctrl thread routine didn't call a cancellation point.
lib/librte_eal/common/eal_common_thread.c | 29 +++++++++++++----------
1 file changed, 17 insertions(+), 12 deletions(-)
diff --git a/lib/librte_eal/common/eal_common_thread.c b/lib/librte_eal/common/eal_common_thread.c
index 3347e91bf..03dbcd9e8 100644
--- a/lib/librte_eal/common/eal_common_thread.c
+++ b/lib/librte_eal/common/eal_common_thread.c
@@ -187,14 +187,18 @@ static void *ctrl_thread_init(void *arg)
eal_get_internal_configuration();
rte_cpuset_t *cpuset = &internal_conf->ctrl_cpuset;
struct rte_thread_ctrl_params *params = arg;
- void *(*start_routine)(void *) = params->start_routine;
+ void *(*start_routine)(void *);
void *routine_arg = params->arg;
__rte_thread_init(rte_lcore_id(), cpuset);
pthread_barrier_wait(¶ms->configured);
+ start_routine = params->start_routine;
ctrl_params_free(params);
+ if (start_routine == NULL)
+ return NULL;
+
return start_routine(routine_arg);
}
@@ -218,14 +222,12 @@ rte_ctrl_thread_create(pthread_t *thread, const char *name,
params->refcnt = 2;
ret = pthread_barrier_init(¶ms->configured, NULL, 2);
- if (ret != 0) {
- free(params);
- return -ret;
- }
+ if (ret != 0)
+ goto fail_no_barrier;
ret = pthread_create(thread, attr, ctrl_thread_init, (void *)params);
if (ret != 0)
- goto fail;
+ goto fail_with_barrier;
if (name != NULL) {
ret = rte_thread_setname(*thread, name);
@@ -236,19 +238,22 @@ rte_ctrl_thread_create(pthread_t *thread, const char *name,
ret = pthread_setaffinity_np(*thread, sizeof(*cpuset), cpuset);
if (ret != 0)
- goto fail_cancel;
+ params->start_routine = NULL;
pthread_barrier_wait(¶ms->configured);
ctrl_params_free(params);
- return 0;
+ if (ret != 0)
+ /* start_routine has been set to NULL above; */
+ /* ctrl thread will exit immediately */
+ pthread_join(*thread, NULL);
-fail_cancel:
- pthread_cancel(*thread);
- pthread_join(*thread, NULL);
+ return -ret;
-fail:
+fail_with_barrier:
pthread_barrier_destroy(¶ms->configured);
+
+fail_no_barrier:
free(params);
return -ret;
--
2.25.1
next prev parent reply other threads:[~2021-04-07 20:28 UTC|newest]
Thread overview: 24+ messages / expand[flat|nested] mbox.gz Atom feed top
2021-03-24 13:04 [dpdk-stable] [PATCH] eal: fix possible UB on creation of ctrl thread Luc Pelletier
2021-03-25 11:27 ` [dpdk-stable] [PATCH v2] eal: fix race in ctrl thread creation Olivier Matz
2021-03-25 14:42 ` Luc Pelletier
2021-04-02 4:34 ` [dpdk-stable] [dpdk-dev] " Honnappa Nagarahalli
2021-04-06 16:15 ` [dpdk-stable] [PATCH v3] " Luc Pelletier
2021-04-06 21:10 ` Honnappa Nagarahalli
2021-04-07 12:35 ` [dpdk-stable] [PATCH v4] " Luc Pelletier
2021-04-07 12:53 ` [dpdk-stable] [PATCH v5] " Luc Pelletier
2021-04-07 13:22 ` Luc Pelletier
2021-04-07 13:31 ` Olivier Matz
2021-04-07 14:42 ` [dpdk-stable] [PATCH v6] " Luc Pelletier
2021-04-07 14:57 ` Olivier Matz
2021-04-07 15:29 ` [dpdk-stable] [PATCH v7] " Luc Pelletier
2021-04-07 17:15 ` Honnappa Nagarahalli
2021-04-07 15:15 ` [dpdk-stable] [PATCH v5] " Honnappa Nagarahalli
2021-04-07 20:16 ` [dpdk-stable] [PATCH 1/2] " Luc Pelletier
2021-04-08 14:17 ` Olivier Matz
2021-04-08 17:06 ` Honnappa Nagarahalli
2021-04-07 20:16 ` Luc Pelletier [this message]
2021-04-08 14:20 ` [dpdk-stable] [PATCH 2/2] eal: fix hang in ctrl thread creation error logic Olivier Matz
2021-04-08 18:01 ` Luc Pelletier
2021-04-09 8:13 ` [dpdk-stable] [dpdk-dev] " David Marchand
2021-04-08 17:07 ` [dpdk-stable] " Honnappa Nagarahalli
2021-04-09 14:34 ` David Marchand
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