[v3] eal: fix use wrong time API

Message ID 1620186231-35245-1-git-send-email-fengchengwen@huawei.com (mailing list archive)
State Superseded, archived
Delegated to: Thomas Monjalon
Headers
Series [v3] eal: fix use wrong time API |

Checks

Context Check Description
ci/checkpatch success coding style OK
ci/iol-testing success Testing PASS
ci/iol-abi-testing success Testing PASS
ci/iol-mellanox-Performance success Performance Testing PASS
ci/github-robot success github build: passed
ci/iol-intel-Performance success Performance Testing PASS
ci/iol-intel-Functional fail Functional Testing issues
ci/Intel-compilation success Compilation OK
ci/intel-Testing success Testing PASS

Commit Message

Chengwen Feng May 5, 2021, 3:43 a.m. UTC
  Currently, the mp uses gettimeofday() API to get the time, and used as
timeout parameter.

But the time which gets from gettimeofday() API isn't monotonically
increasing. The process may fail if the system time is changed.

This fixes it by using clock_gettime() API with monotonic attribution.

Fixes: 783b6e54971d ("eal: add synchronous multi-process communication")
Fixes: f05e26051c15 ("eal: add IPC asynchronous request")
Cc: stable@dpdk.org

Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
Acked-by: Morten Brørup <mb@smartsharesystems.com>
---
v3:
* add acked-by.
* change patch's author.

v2:
* get rid of the CLOCK_TYPE_ID definition and use CLOCK_MONOTONIC
instead.
---
 lib/eal/common/eal_common_proc.c | 39 +++++++++++++--------------------------
 1 file changed, 13 insertions(+), 26 deletions(-)
  

Comments

Thomas Monjalon May 11, 2021, 7:36 a.m. UTC | #1
05/05/2021 05:43, Chengwen Feng:
> Currently, the mp uses gettimeofday() API to get the time, and used as
> timeout parameter.
> 
> But the time which gets from gettimeofday() API isn't monotonically
> increasing. The process may fail if the system time is changed.
> 
> This fixes it by using clock_gettime() API with monotonic attribution.
> 
> Fixes: 783b6e54971d ("eal: add synchronous multi-process communication")
> Fixes: f05e26051c15 ("eal: add IPC asynchronous request")
> Cc: stable@dpdk.org
> 
> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
> Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
> Acked-by: Morten Brørup <mb@smartsharesystems.com>
> ---
> v3:
> * add acked-by.
> * change patch's author.

I did some comments on v2 about potential errors to catch,
but you sent this v3 without participating in v2 discussion.
  
Chengwen Feng May 11, 2021, 10:49 a.m. UTC | #2
On 2021/5/11 15:36, Thomas Monjalon wrote:
> 05/05/2021 05:43, Chengwen Feng:
>> Currently, the mp uses gettimeofday() API to get the time, and used as
>> timeout parameter.
>>
>> But the time which gets from gettimeofday() API isn't monotonically
>> increasing. The process may fail if the system time is changed.
>>
>> This fixes it by using clock_gettime() API with monotonic attribution.
>>
>> Fixes: 783b6e54971d ("eal: add synchronous multi-process communication")
>> Fixes: f05e26051c15 ("eal: add IPC asynchronous request")
>> Cc: stable@dpdk.org
>>
>> Signed-off-by: Chengwen Feng <fengchengwen@huawei.com>
>> Signed-off-by: Min Hu (Connor) <humin29@huawei.com>
>> Acked-by: Morten Brørup <mb@smartsharesystems.com>
>> ---
>> v3:
>> * add acked-by.
>> * change patch's author.
> 
> I did some comments on v2 about potential errors to catch,
> but you sent this v3 without participating in v2 discussion.
> 
> 

Fixed in v4, thanks

> 
> .
>
  

Patch

diff --git a/lib/eal/common/eal_common_proc.c b/lib/eal/common/eal_common_proc.c
index 6d1af3c..6af8ba2 100644
--- a/lib/eal/common/eal_common_proc.c
+++ b/lib/eal/common/eal_common_proc.c
@@ -490,14 +490,8 @@  async_reply_handle_thread_unsafe(void *arg)
 	struct pending_request *req = (struct pending_request *)arg;
 	enum async_action action;
 	struct timespec ts_now;
-	struct timeval now;
 
-	if (gettimeofday(&now, NULL) < 0) {
-		RTE_LOG(ERR, EAL, "Cannot get current time\n");
-		goto no_trigger;
-	}
-	ts_now.tv_nsec = now.tv_usec * 1000;
-	ts_now.tv_sec = now.tv_sec;
+	clock_gettime(CLOCK_MONOTONIC, &ts_now);
 
 	action = process_async_request(req, &ts_now);
 
@@ -896,6 +890,7 @@  mp_request_sync(const char *dst, struct rte_mp_msg *req,
 	       struct rte_mp_reply *reply, const struct timespec *ts)
 {
 	int ret;
+	pthread_condattr_t attr;
 	struct rte_mp_msg msg, *tmp;
 	struct pending_request pending_req, *exist;
 
@@ -904,7 +899,9 @@  mp_request_sync(const char *dst, struct rte_mp_msg *req,
 	strlcpy(pending_req.dst, dst, sizeof(pending_req.dst));
 	pending_req.request = req;
 	pending_req.reply = &msg;
-	pthread_cond_init(&pending_req.sync.cond, NULL);
+	pthread_condattr_init(&attr);
+	pthread_condattr_setclock(&attr, CLOCK_MONOTONIC);
+	pthread_cond_init(&pending_req.sync.cond, &attr);
 
 	exist = find_pending_request(dst, req->name);
 	if (exist) {
@@ -967,8 +964,7 @@  rte_mp_request_sync(struct rte_mp_msg *req, struct rte_mp_reply *reply,
 	int dir_fd, ret = -1;
 	DIR *mp_dir;
 	struct dirent *ent;
-	struct timeval now;
-	struct timespec end;
+	struct timespec now, end;
 	const struct internal_config *internal_conf =
 		eal_get_internal_configuration();
 
@@ -987,15 +983,10 @@  rte_mp_request_sync(struct rte_mp_msg *req, struct rte_mp_reply *reply,
 		return -1;
 	}
 
-	if (gettimeofday(&now, NULL) < 0) {
-		RTE_LOG(ERR, EAL, "Failed to get current time\n");
-		rte_errno = errno;
-		goto end;
-	}
-
-	end.tv_nsec = (now.tv_usec * 1000 + ts->tv_nsec) % 1000000000;
+	clock_gettime(CLOCK_MONOTONIC, &now);
+	end.tv_nsec = (now.tv_nsec + ts->tv_nsec) % 1000000000;
 	end.tv_sec = now.tv_sec + ts->tv_sec +
-			(now.tv_usec * 1000 + ts->tv_nsec) / 1000000000;
+			(now.tv_nsec + ts->tv_nsec) / 1000000000;
 
 	/* for secondary process, send request to the primary process only */
 	if (rte_eal_process_type() == RTE_PROC_SECONDARY) {
@@ -1069,7 +1060,7 @@  rte_mp_request_async(struct rte_mp_msg *req, const struct timespec *ts,
 	int dir_fd, ret = 0;
 	DIR *mp_dir;
 	struct dirent *ent;
-	struct timeval now;
+	struct timespec now;
 	struct timespec *end;
 	bool dummy_used = false;
 	const struct internal_config *internal_conf =
@@ -1086,11 +1077,6 @@  rte_mp_request_async(struct rte_mp_msg *req, const struct timespec *ts,
 		return -1;
 	}
 
-	if (gettimeofday(&now, NULL) < 0) {
-		RTE_LOG(ERR, EAL, "Failed to get current time\n");
-		rte_errno = errno;
-		return -1;
-	}
 	copy = calloc(1, sizeof(*copy));
 	dummy = calloc(1, sizeof(*dummy));
 	param = calloc(1, sizeof(*param));
@@ -1108,9 +1094,10 @@  rte_mp_request_async(struct rte_mp_msg *req, const struct timespec *ts,
 	end = &param->end;
 	reply = &param->user_reply;
 
-	end->tv_nsec = (now.tv_usec * 1000 + ts->tv_nsec) % 1000000000;
+	clock_gettime(CLOCK_MONOTONIC, &now);
+	end->tv_nsec = (now.tv_nsec + ts->tv_nsec) % 1000000000;
 	end->tv_sec = now.tv_sec + ts->tv_sec +
-			(now.tv_usec * 1000 + ts->tv_nsec) / 1000000000;
+			(now.tv_nsec + ts->tv_nsec) / 1000000000;
 	reply->nb_sent = 0;
 	reply->nb_received = 0;
 	reply->msgs = NULL;