[dpdk-dev] Does memif support primary<->secondary process communication?

[dpdk-dev] Does memif support primary<->secondary process communication?

[Wu, Jianyue (NSB - CN/Hangzhou)]

Hello,

May I ask a question about memif?
When I'm trying to develop a communication mechanism for two processes, which also need to share memzones between the processes, so need primary<->secondary.
https://doc.dpdk.org/guides/nics/memif.html
But from the guideline, it seems always use primary<->primary. Does it support primary<->secondary? Thanks indeed in advance!

Best Regards,
Dave(Jianyue)

Re: [dpdk-dev] Does memif support primary<->secondary process communication?

[Wu, Jianyue (NSB - CN/Hangzhou)]

BTW, I use it for primary and secondary communication, so that will use memif to share data between primary and secondary. Thanks.

Best Regards,
Dave(Jianyue)

From: Wu, Jianyue (NSB - CN/Hangzhou)
Sent: 2021年6月9日 19:26
To: users@dpdk.org; 'dev@dpdk.org' <dev@dpdk.org>
Subject: Does memif support primary<->secondary process communication?

Hello,

May I ask a question about memif?
When I’m trying to develop a communication mechanism for two processes, which also need to share memzones between the processes, so need primary<->secondary.
https://doc.dpdk.org/guides/nics/memif.html
But from the guideline, it seems always use primary<->primary. Does it support primary<->secondary? Thanks indeed in advance!

Best Regards,
Dave(Jianyue)

[PATCH] eal/linux: enhanced error handling for affinity

[Jianyue Wu (NSB)]

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Hello,

Good day~
I hope this message finds you well. I am writing to submit a patch for consideration, which primarily adds enhanced error handling for affinity sets within the eal/linux of DPDK. Unfortunately, my current environment does not support git send-email, so I am sending this patch attached to this email.

Thank you~
Best regards,
Dave


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[-- Attachment #2: 0001-eal-linux-enhanced-error-handling-for-affinity.patch --]
[-- Type: application/octet-stream, Size: 3326 bytes --]

From 89d879f762dc5e6901fc6cde06b8c36b641424de Mon Sep 17 00:00:00 2001
From: Jianyue Wu <jianyue.wu@nokia-sbell.com>
Date: Fri, 19 Apr 2024 13:57:35 +0300
Subject: [PATCH] eal/linux: enhanced error handling for affinity

Improve the robustness of setting thread affinity in DPDK
by adding detailed error logging.

Changes:
1. Set `errno` to 0 before calling `pthread_setaffinity_np()` to ensure
clean error status.
2. Check the return value of `pthread_setaffinity_np()` and log an error
if the call fails.
3. Include the current thread name, the intended CPU set, and a detailed
error message in the log.

Sample prints:
EAL: Cannot set affinity for thread dpdk-test with cpus 0,
ret: 22, errno: 0, error description: Success
EAL: Cannot set affinity for thread dpdk-worker1 with cpus 1,
ret: 22, errno: 0, error description: Success

Signed-off-by: Jianyue Wu <jianyue.wu@nokia-sbell.com>
---
 lib/eal/unix/rte_thread.c | 51 +++++++++++++++++++++++++++++++++++++--
 1 file changed, 49 insertions(+), 2 deletions(-)

diff --git a/lib/eal/unix/rte_thread.c b/lib/eal/unix/rte_thread.c
index 1b4c73f58e..56bc7995eb 100644
--- a/lib/eal/unix/rte_thread.c
+++ b/lib/eal/unix/rte_thread.c
@@ -5,6 +5,7 @@
 
 #include <errno.h>
 #include <pthread.h>
+#include <sched.h>
 #include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
@@ -114,6 +115,35 @@ thread_start_wrapper(void *arg)
 	return (void *)(uintptr_t)thread_func(thread_args);
 }
 
+/* Function to convert cpu_set_t to a string. */
+static void cpuset_to_string(const cpu_set_t *cpuset,
+			char *cpus_str, size_t cpus_str_size) {
+	int cpu;
+	// Track the current position in the string
+	size_t offset = 0;
+
+	// Clear the string buffer
+	memset(cpus_str, 0, cpus_str_size);
+	cpus_str_size = RTE_MAX_LCORE < cpus_str_size ?
+		RTE_MAX_LCORE : cpus_str_size;
+
+	// Iterate over each CPU core, and check if it is included in the set
+	for (cpu = 0; cpu < RTE_MAX_LCORE && offset < cpus_str_size - 1; ++cpu) {
+		if (CPU_ISSET(cpu, cpuset)) {
+			// Append the current CPU number to the string
+			int written = snprintf(cpus_str + offset, cpus_str_size - offset,
+				"%s%d", (offset > 0 ? "," : ""), cpu);
+			if (written > 0)
+				offset += written;
+			if (offset >= cpus_str_size - 1)
+				break;
+			}
+	}
+
+	// Ensure the string is properly terminated
+	cpus_str[cpus_str_size - 1] = '\0';
+}
+
 int
 rte_thread_create(rte_thread_t *thread_id,
 		const rte_thread_attr_t *thread_attr,
@@ -369,8 +399,25 @@ int
 rte_thread_set_affinity_by_id(rte_thread_t thread_id,
 		const rte_cpuset_t *cpuset)
 {
-	return pthread_setaffinity_np((pthread_t)thread_id.opaque_id,
-		sizeof(*cpuset), cpuset);
+	int ret;
+	char cpus_str[RTE_MAX_LCORE + 1] = {'\0'};
+	char thread_name[RTE_MAX_THREAD_NAME_LEN] = {'\0'};
+
+	errno = 0;
+	ret = pthread_setaffinity_np((pthread_t)thread_id.opaque_id,
+				sizeof(*cpuset), cpuset);
+	if (ret != 0) {
+		if (pthread_getname_np((pthread_t)thread_id.opaque_id,
+					thread_name, sizeof(thread_name)) != 0)
+			EAL_LOG(ERR, "pthread_getname_np failed!");
+		cpuset_to_string(cpuset, cpus_str, sizeof(cpus_str));
+		EAL_LOG(ERR, "Cannot set affinity for thread %s with cpus %s, "
+			"ret: %d, errno: %d, error description: %s",
+			thread_name, cpus_str,
+			ret, errno, strerror(errno));
+	}
+
+	return ret;
 }
 
 int
-- 
2.42.0

[PATCH] eal/linux: enhanced error handling for affinity

[Ferruh Yigit]

From: Jianyue Wu <jianyue.wu@nokia-sbell.com>

Improve the robustness of setting thread affinity in DPDK
by adding detailed error logging.

Changes:
1. Set `errno` to 0 before calling `pthread_setaffinity_np()` to ensure
clean error status.
2. Check the return value of `pthread_setaffinity_np()` and log an error
if the call fails.
3. Include the current thread name, the intended CPU set, and a detailed
error message in the log.

Sample prints:
EAL: Cannot set affinity for thread dpdk-test with cpus 0,
ret: 22, errno: 0, error description: Success
EAL: Cannot set affinity for thread dpdk-worker1 with cpus 1,
ret: 22, errno: 0, error description: Success

Signed-off-by: Jianyue Wu <jianyue.wu@nokia-sbell.com>
---
 .mailmap                  |  1 +
 lib/eal/unix/rte_thread.c | 51 +++++++++++++++++++++++++++++++++++++--
 2 files changed, 50 insertions(+), 2 deletions(-)

diff --git a/.mailmap b/.mailmap
index 3843868716bd..66cff91f30a9 100644
--- a/.mailmap
+++ b/.mailmap
@@ -639,6 +639,7 @@ Jianfeng Tan <jianfeng.tan@intel.com>
 Jiangu Zhao <zhaojg@arraynetworks.com.cn>
 Jianwei Ma <jianwei.ma@intel.com>
 Jianwei Mei <jianweix.mei@intel.com>
+Jianyue Wu <jianyue.wu@nokia-sbell.com>
 Jiaqi Min <jiaqix.min@intel.com>
 Jiawei Wang <jiaweiw@nvidia.com> <jiaweiw@mellanox.com>
 Jiawei Zhu <zhujiawei12@huawei.com>
diff --git a/lib/eal/unix/rte_thread.c b/lib/eal/unix/rte_thread.c
index 1b4c73f58e91..56bc7995eb5f 100644
--- a/lib/eal/unix/rte_thread.c
+++ b/lib/eal/unix/rte_thread.c
@@ -5,6 +5,7 @@
 
 #include <errno.h>
 #include <pthread.h>
+#include <sched.h>
 #include <stdbool.h>
 #include <stdlib.h>
 #include <string.h>
@@ -114,6 +115,35 @@ thread_start_wrapper(void *arg)
 	return (void *)(uintptr_t)thread_func(thread_args);
 }
 
+/* Function to convert cpu_set_t to a string. */
+static void cpuset_to_string(const cpu_set_t *cpuset,
+			char *cpus_str, size_t cpus_str_size) {
+	int cpu;
+	// Track the current position in the string
+	size_t offset = 0;
+
+	// Clear the string buffer
+	memset(cpus_str, 0, cpus_str_size);
+	cpus_str_size = RTE_MAX_LCORE < cpus_str_size ?
+		RTE_MAX_LCORE : cpus_str_size;
+
+	// Iterate over each CPU core, and check if it is included in the set
+	for (cpu = 0; cpu < RTE_MAX_LCORE && offset < cpus_str_size - 1; ++cpu) {
+		if (CPU_ISSET(cpu, cpuset)) {
+			// Append the current CPU number to the string
+			int written = snprintf(cpus_str + offset, cpus_str_size - offset,
+				"%s%d", (offset > 0 ? "," : ""), cpu);
+			if (written > 0)
+				offset += written;
+			if (offset >= cpus_str_size - 1)
+				break;
+			}
+	}
+
+	// Ensure the string is properly terminated
+	cpus_str[cpus_str_size - 1] = '\0';
+}
+
 int
 rte_thread_create(rte_thread_t *thread_id,
 		const rte_thread_attr_t *thread_attr,
@@ -369,8 +399,25 @@ int
 rte_thread_set_affinity_by_id(rte_thread_t thread_id,
 		const rte_cpuset_t *cpuset)
 {
-	return pthread_setaffinity_np((pthread_t)thread_id.opaque_id,
-		sizeof(*cpuset), cpuset);
+	int ret;
+	char cpus_str[RTE_MAX_LCORE + 1] = {'\0'};
+	char thread_name[RTE_MAX_THREAD_NAME_LEN] = {'\0'};
+
+	errno = 0;
+	ret = pthread_setaffinity_np((pthread_t)thread_id.opaque_id,
+				sizeof(*cpuset), cpuset);
+	if (ret != 0) {
+		if (pthread_getname_np((pthread_t)thread_id.opaque_id,
+					thread_name, sizeof(thread_name)) != 0)
+			EAL_LOG(ERR, "pthread_getname_np failed!");
+		cpuset_to_string(cpuset, cpus_str, sizeof(cpus_str));
+		EAL_LOG(ERR, "Cannot set affinity for thread %s with cpus %s, "
+			"ret: %d, errno: %d, error description: %s",
+			thread_name, cpus_str,
+			ret, errno, strerror(errno));
+	}
+
+	return ret;
 }
 
 int
-- 
2.34.1

Re: [PATCH] eal/linux: enhanced error handling for affinity

[Ferruh Yigit]

On 4/22/2024 2:23 PM, Jianyue Wu (NSB) wrote:
> Hello,
> 
>  
> 
> Good day~
> 
> I hope this message finds you well. I am writing to submit a patch for
> consideration, which primarily adds enhanced error handling for affinity
> sets within the eal/linux of DPDK. Unfortunately, my current environment
> does not support git send-email, so I am sending this patch attached to
> this email.
> 

Thanks Dave, I sent the patch for you, you can follow the CI test
results from patchwork link:
https://patchwork.dpdk.org/project/dpdk/patch/20240422134917.3740545-1-ferruh.yigit@amd.com/

Re: [PATCH] eal/linux: enhanced error handling for affinity

[Stephen Hemminger]

On Mon, 22 Apr 2024 13:23:50 +0000
"Jianyue Wu (NSB)" <jianyue.wu@nokia-sbell.com> wrote:

> +/* Function to convert cpu_set_t to a string. */
> +static void cpuset_to_string(const cpu_set_t *cpuset,
> +			char *cpus_str, size_t cpus_str_size) {
> +	int cpu;
> +	// Track the current position in the string

DPDK does not use C++ style comments.

All patches should match the style of existing code.

Re: [PATCH] eal/linux: enhanced error handling for affinity

[Stephen Hemminger]

On Mon, 22 Apr 2024 13:23:50 +0000
"Jianyue Wu (NSB)" <jianyue.wu@nokia-sbell.com> wrote:

> +	char cpus_str[RTE_MAX_LCORE + 1] = {'\0'};
> +	char thread_name[RTE_MAX_THREAD_NAME_LEN] = {'\0'};
> +

You don't need '\0' here, just doing { } will have same effect.

Re: [PATCH] eal/linux: enhanced error handling for affinity

[Stephen Hemminger]

On Mon, 22 Apr 2024 13:23:50 +0000
"Jianyue Wu (NSB)" <jianyue.wu@nokia-sbell.com> wrote:

> +		EAL_LOG(ERR, "Cannot set affinity for thread %s with cpus %s, "
> +			"ret: %d, errno: %d, error description: %s",
> +			thread_name, cpus_str,
> +			ret, errno, strerror(errno));
> +	}

That error message is way too long, and error strings should not be broken across lines.

			"Set affinity thread %s to %s failed: %s"

And it is a lot effort to deduce the cpuset and thread name here.
Probably better to just move the error message back to the caller.

RE: [PATCH] eal/linux: enhanced error handling for affinity

[Jianyue Wu (NSB)]

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Hello,

Please disregard this email; I will use a different mailbox instead.

Thank you~
Best regards,
Dave

From: Jianyue Wu (NSB)
Sent: 2024年4月22日 21:24
To: 'roretzla@linux.microsoft.com' <roretzla@linux.microsoft.com>; 'thomas@monjalon.net' <thomas@monjalon.net>; 'david.marchand@redhat.com' <david.marchand@redhat.com>
Cc: 'dev@dpdk.org' <dev@dpdk.org>
Subject: [PATCH] eal/linux: enhanced error handling for affinity

Hello,

Good day~
I hope this message finds you well. I am writing to submit a patch for consideration, which primarily adds enhanced error handling for affinity sets within the eal/linux of DPDK. Unfortunately, my current environment does not support git send-email, so I am sending this patch attached to this email.

Thank you~
Best regards,
Dave


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RE: [PATCH v2] eal/linux: enhanced error handling for affinity

[Jianyue Wu (NSB)]

[-- Attachment #1.1: Type: text/plain, Size: 1079 bytes --]

Hello,

I've noticed some coding style issues eal/linux: enhanced error handling for affinity - Patchwork (dpdk.org)<https://patches.dpdk.org/project/dpdk/patch/20240422134917.3740545-1-ferruh.yigit@amd.com/> and have attempted to update the patch accordingly. Could you please help by updating it with version 2 of the patch? Thank you very much! 😊

Thank you~
Best regards,
Dave

From: Jianyue Wu (NSB)
Sent: 2024年4月22日 21:24
To: 'roretzla@linux.microsoft.com' <roretzla@linux.microsoft.com>; 'thomas@monjalon.net' <thomas@monjalon.net>; 'david.marchand@redhat.com' <david.marchand@redhat.com>
Cc: 'dev@dpdk.org' <dev@dpdk.org>
Subject: [PATCH] eal/linux: enhanced error handling for affinity

Hello,

Good day~
I hope this message finds you well. I am writing to submit a patch for consideration, which primarily adds enhanced error handling for affinity sets within the eal/linux of DPDK. Unfortunately, my current environment does not support git send-email, so I am sending this patch attached to this email.

Thank you~
Best regards,
Dave


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[-- Attachment #2: 0001-eal-linux-enhanced-error-handling-for-affinity.patch --]
[-- Type: application/octet-stream, Size: 2035 bytes --]

From bc7ed0f08373b0159a5990511f15312815bf36bd Mon Sep 17 00:00:00 2001
From: Jianyue Wu <jianyue.wu@nokia-sbell.com>
Date: Fri, 19 Apr 2024 13:57:35 +0300
Subject: [PATCH v2] eal/linux: enhanced error handling for affinity

Improve the robustness of setting thread affinity in DPDK
by adding detailed error logging.

Changes:
1. Check the return value of pthread_setaffinity_np() and log an error
if the call fails.
2. Include the current thread name, the intended CPU set, and a detailed
error message in the log.

Sample prints:
EAL: Cannot set affinity for thread dpdk-test with cpus 0,
ret: 22, errno: 0, error description: Success
EAL: Cannot set affinity for thread dpdk-worker1 with cpus 1,
ret: 22, errno: 0, error description: Success

Signed-off-by: Jianyue Wu <jianyue.wu@nokia-sbell.com>
---
 lib/eal/unix/rte_thread.c | 22 ++++++++++++++++++++--
 1 file changed, 20 insertions(+), 2 deletions(-)

diff --git a/lib/eal/unix/rte_thread.c b/lib/eal/unix/rte_thread.c
index 1b4c73f58e..8f9eaf0dcf 100644
--- a/lib/eal/unix/rte_thread.c
+++ b/lib/eal/unix/rte_thread.c
@@ -369,8 +369,26 @@ int
 rte_thread_set_affinity_by_id(rte_thread_t thread_id,
 		const rte_cpuset_t *cpuset)
 {
-	return pthread_setaffinity_np((pthread_t)thread_id.opaque_id,
-		sizeof(*cpuset), cpuset);
+	int ret;
+	char cpus_str[RTE_CPU_AFFINITY_STR_LEN] = {'\0'};
+	char thread_name[RTE_MAX_THREAD_NAME_LEN] = {'\0'};
+
+	errno = 0;
+	ret = pthread_setaffinity_np((pthread_t)thread_id.opaque_id,
+				sizeof(*cpuset), cpuset);
+	if (ret != 0) {
+		if (pthread_getname_np((pthread_t)thread_id.opaque_id,
+					thread_name, sizeof(thread_name)) != 0)
+			EAL_LOG(ERR, "pthread_getname_np failed!");
+		if (eal_thread_dump_affinity(cpuset, cpus_str, RTE_CPU_AFFINITY_STR_LEN) != 0)
+			EAL_LOG(ERR, "eal_thread_dump_affinity failed!");
+		EAL_LOG(ERR, "Cannot set affinity for thread %s with cpus %s, "
+			"ret: %d, errno: %d, error description: %s",
+			thread_name, cpus_str,
+			ret, errno, strerror(errno));
+	}
+
+	return ret;
 }
 
 int
-- 
2.34.1