[PATCH 0/2] mempool: add rte_errno, and turn functions into single-exit ones

[PATCH 0/2] mempool: add rte_errno, and turn functions into single-exit ones

[Ariel Otilibili]

Hello,

This series is for BugZilla ID 1559.

rte_mempool_set_ops_byname() did not set rte_errno for error exit. As well, other functions did not consistently set the variable.

For avoiding that, they are turned into single-exit functions.

Thank you,

Ariel Otilibili (2):
  mempool: add rte_errno in rte_mempool_set_ops_byname
  mempool: turn functions into single-exit ones

 lib/mempool/rte_mempool_ops.c | 44 ++++++++++++++++++++++++++---------
 1 file changed, 33 insertions(+), 11 deletions(-)

-- 
2.30.2

[PATCH 1/2] mempool: add rte_errno in rte_mempool_set_ops_byname

[Ariel Otilibili]

rte_errno is not set for error exits. For the scenario described in
BugZilla ID 1559, rte_mempool_create_empty() calls
rte_mempool_set_ops_byname(), but does not set as well the proper
rte_errno.

rte_errno is now set in rte_mempool_set_ops_byname(); from there it
cascades down to the calling function.

Bugzilla ID: 1559
Signed-off-by: Ariel Otilibili <ariel.otilibili@6wind.com>
---
 lib/mempool/rte_mempool_ops.c | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/lib/mempool/rte_mempool_ops.c b/lib/mempool/rte_mempool_ops.c
index 1b33380259b3..b5c68ac61b67 100644
--- a/lib/mempool/rte_mempool_ops.c
+++ b/lib/mempool/rte_mempool_ops.c
@@ -169,8 +169,10 @@ rte_mempool_set_ops_byname(struct rte_mempool *mp, const char *name,
 	unsigned i;
 
 	/* too late, the mempool is already populated. */
-	if (mp->flags & RTE_MEMPOOL_F_POOL_CREATED)
-		return -EEXIST;
+	if (mp->flags & RTE_MEMPOOL_F_POOL_CREATED) {
+		rte_errno = EEXIST;
+		return -rte_errno;
+	}
 
 	for (i = 0; i < rte_mempool_ops_table.num_ops; i++) {
 		if (!strcmp(name,
@@ -180,8 +182,10 @@ rte_mempool_set_ops_byname(struct rte_mempool *mp, const char *name,
 		}
 	}
 
-	if (ops == NULL)
-		return -EINVAL;
+	if (ops == NULL) {
+		rte_errno = EINVAL;
+		return -rte_errno;
+	}
 
 	mp->ops_index = i;
 	mp->pool_config = pool_config;
-- 
2.30.2

[PATCH 2/2] mempool: turn functions into single-exit ones

[Ariel Otilibili]

Some functions did not set rte_errno; for avoiding that, they are turned
into single-exit ones.

Bugzilla ID: 1559
Signed-off-by: Ariel Otilibili <ariel.otilibili@6wind.com>
---
 lib/mempool/rte_mempool_ops.c | 38 ++++++++++++++++++++++++++---------
 1 file changed, 28 insertions(+), 10 deletions(-)

diff --git a/lib/mempool/rte_mempool_ops.c b/lib/mempool/rte_mempool_ops.c
index b5c68ac61b67..bf4328645196 100644
--- a/lib/mempool/rte_mempool_ops.c
+++ b/lib/mempool/rte_mempool_ops.c
@@ -33,7 +33,9 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
 		rte_spinlock_unlock(&rte_mempool_ops_table.sl);
 		RTE_MEMPOOL_LOG(ERR,
 			"Maximum number of mempool ops structs exceeded");
-		return -ENOSPC;
+		rte_errno = ENOSPC;
+		ops_index = -rte_errno;
+		goto out;
 	}
 
 	if (h->alloc == NULL || h->enqueue == NULL ||
@@ -41,7 +43,9 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
 		rte_spinlock_unlock(&rte_mempool_ops_table.sl);
 		RTE_MEMPOOL_LOG(ERR,
 			"Missing callback while registering mempool ops");
-		return -EINVAL;
+		rte_errno = -EINVAL;
+		ops_index = -rte_errno;
+		goto out;
 	}
 
 	if (strlen(h->name) >= sizeof(ops->name) - 1) {
@@ -49,7 +53,8 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
 		RTE_MEMPOOL_LOG(DEBUG, "%s(): mempool_ops <%s>: name too long",
 				__func__, h->name);
 		rte_errno = EEXIST;
-		return -EEXIST;
+		ops_index = -rte_errno;
+		goto out;
 	}
 
 	ops_index = rte_mempool_ops_table.num_ops++;
@@ -67,6 +72,7 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
 
 	rte_spinlock_unlock(&rte_mempool_ops_table.sl);
 
+out:
 	return ops_index;
 }
 
@@ -151,12 +157,19 @@ rte_mempool_ops_get_info(const struct rte_mempool *mp,
 			 struct rte_mempool_info *info)
 {
 	struct rte_mempool_ops *ops;
+	int ret;
 
 	ops = rte_mempool_get_ops(mp->ops_index);
 
-	if (ops->get_info == NULL)
-		return -ENOTSUP;
-	return ops->get_info(mp, info);
+	if (ops->get_info == NULL) {
+		rte_errno = ENOTSUP;
+		ret = -rte_errno;
+		goto out;
+	}
+	ret = ops->get_info(mp, info);
+
+out:
+	return ret;
 }
 
 
@@ -166,12 +179,14 @@ rte_mempool_set_ops_byname(struct rte_mempool *mp, const char *name,
 	void *pool_config)
 {
 	struct rte_mempool_ops *ops = NULL;
+	int ret = 0;
 	unsigned i;
 
 	/* too late, the mempool is already populated. */
 	if (mp->flags & RTE_MEMPOOL_F_POOL_CREATED) {
 		rte_errno = EEXIST;
-		return -rte_errno;
+		ret = -rte_errno;
+		goto out;
 	}
 
 	for (i = 0; i < rte_mempool_ops_table.num_ops; i++) {
@@ -182,13 +197,16 @@ rte_mempool_set_ops_byname(struct rte_mempool *mp, const char *name,
 		}
 	}
 
-	if (ops == NULL) {
+	if (!ops) {
 		rte_errno = EINVAL;
-		return -rte_errno;
+		ret = -rte_errno;
+		goto out;
 	}
 
 	mp->ops_index = i;
 	mp->pool_config = pool_config;
 	rte_mempool_trace_set_ops_byname(mp, name, pool_config);
-	return 0;
+
+out:
+	return ret;
 }
-- 
2.30.2

RE: [PATCH 2/2] mempool: turn functions into single-exit ones

[Konstantin Ananyev]

> Some functions did not set rte_errno; for avoiding that, they are turned
> into single-exit ones.
> 
> Bugzilla ID: 1559
> Signed-off-by: Ariel Otilibili <ariel.otilibili@6wind.com>

But reading through public API comments none of these functions are 
expected to set rte_errno value.
If rte_mempool_create_empty() forgets to set rte_errno, why it is not
enough just to add missing one in rte_mempool_create_empty()?
 

> ---
>  lib/mempool/rte_mempool_ops.c | 38 ++++++++++++++++++++++++++---------
>  1 file changed, 28 insertions(+), 10 deletions(-)
> 
> diff --git a/lib/mempool/rte_mempool_ops.c b/lib/mempool/rte_mempool_ops.c
> index b5c68ac61b67..bf4328645196 100644
> --- a/lib/mempool/rte_mempool_ops.c
> +++ b/lib/mempool/rte_mempool_ops.c
> @@ -33,7 +33,9 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
>  		rte_spinlock_unlock(&rte_mempool_ops_table.sl);
>  		RTE_MEMPOOL_LOG(ERR,
>  			"Maximum number of mempool ops structs exceeded");
> -		return -ENOSPC;
> +		rte_errno = ENOSPC;
> +		ops_index = -rte_errno;
> +		goto out;
>  	}
> 
>  	if (h->alloc == NULL || h->enqueue == NULL ||
> @@ -41,7 +43,9 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
>  		rte_spinlock_unlock(&rte_mempool_ops_table.sl);
>  		RTE_MEMPOOL_LOG(ERR,
>  			"Missing callback while registering mempool ops");
> -		return -EINVAL;
> +		rte_errno = -EINVAL;
> +		ops_index = -rte_errno;
> +		goto out;
>  	}
> 
>  	if (strlen(h->name) >= sizeof(ops->name) - 1) {
> @@ -49,7 +53,8 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
>  		RTE_MEMPOOL_LOG(DEBUG, "%s(): mempool_ops <%s>: name too long",
>  				__func__, h->name);
>  		rte_errno = EEXIST;
> -		return -EEXIST;
> +		ops_index = -rte_errno;
> +		goto out;
>  	}
> 
>  	ops_index = rte_mempool_ops_table.num_ops++;
> @@ -67,6 +72,7 @@ rte_mempool_register_ops(const struct rte_mempool_ops *h)
> 
>  	rte_spinlock_unlock(&rte_mempool_ops_table.sl);
> 
> +out:
>  	return ops_index;
>  }
> 
> @@ -151,12 +157,19 @@ rte_mempool_ops_get_info(const struct rte_mempool *mp,
>  			 struct rte_mempool_info *info)
>  {
>  	struct rte_mempool_ops *ops;
> +	int ret;
> 
>  	ops = rte_mempool_get_ops(mp->ops_index);
> 
> -	if (ops->get_info == NULL)
> -		return -ENOTSUP;
> -	return ops->get_info(mp, info);
> +	if (ops->get_info == NULL) {
> +		rte_errno = ENOTSUP;
> +		ret = -rte_errno;
> +		goto out;
> +	}
> +	ret = ops->get_info(mp, info);
> +
> +out:
> +	return ret;
>  }
> 
> 
> @@ -166,12 +179,14 @@ rte_mempool_set_ops_byname(struct rte_mempool *mp, const char *name,
>  	void *pool_config)
>  {
>  	struct rte_mempool_ops *ops = NULL;
> +	int ret = 0;
>  	unsigned i;
> 
>  	/* too late, the mempool is already populated. */
>  	if (mp->flags & RTE_MEMPOOL_F_POOL_CREATED) {
>  		rte_errno = EEXIST;
> -		return -rte_errno;
> +		ret = -rte_errno;
> +		goto out;
>  	}
> 
>  	for (i = 0; i < rte_mempool_ops_table.num_ops; i++) {
> @@ -182,13 +197,16 @@ rte_mempool_set_ops_byname(struct rte_mempool *mp, const char *name,
>  		}
>  	}
> 
> -	if (ops == NULL) {
> +	if (!ops) {
>  		rte_errno = EINVAL;
> -		return -rte_errno;
> +		ret = -rte_errno;
> +		goto out;
>  	}
> 
>  	mp->ops_index = i;
>  	mp->pool_config = pool_config;
>  	rte_mempool_trace_set_ops_byname(mp, name, pool_config);
> -	return 0;
> +
> +out:
> +	return ret;
>  }
> --
> 2.30.2

Re: [PATCH 2/2] mempool: turn functions into single-exit ones

[Ariel Otilibili]

[-- Attachment #1: Type: text/plain, Size: 804 bytes --]

Hi Konstantin,

On Mon, Jan 20, 2025 at 12:44 AM Konstantin Ananyev <
konstantin.ananyev@huawei.com> wrote:

>
>
> > Some functions did not set rte_errno; for avoiding that, they are turned
> > into single-exit ones.
> >
> > Bugzilla ID: 1559
> > Signed-off-by: Ariel Otilibili <ariel.otilibili@6wind.com>
>
> But reading through public API comments none of these functions are
> expected to set rte_errno value.
> If rte_mempool_create_empty() forgets to set rte_errno, why it is not
> enough just to add missing one in rte_mempool_create_empty()?
>
Thanks for your feedback. Indeed, only  rte_mempool_create_empty() returns
a rte_errno
https://doc.dpdk.org/api/rte__mempool_8h.html#a82e301ee33ed7a263ceb4582655dc3ea

I'll push a new series with this change.

Regards,
Ariel

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[PATCH v2 0/2] add rte_errno to rte_mempool_create_empty, and refactor

[Ariel Otilibili]

From: Ariel Otilibili <ariel.otilibili@6wind.com

Hello,

This series is for BugZilla ID 1559. After calling rte_mempool_set_ops_byname(), rte_mempool_create_empty() does not set rte_errno. The API expects rte_errno to bet set in that case.

Thank you,
---
v2
* reworded cover letter and commit messages
* addressed feedback from Konstantin Ananyev
v1 (https://inbox.dpdk.org/dev/20250119174643.2162110-1-ariel.otilibili@6wind.com/)

Ariel Otilibili (2):
  mempool: fix rte_errno in rte_mempool_create_empty
  mempool: make rte_mempool_create_empty a single-exit

 lib/mempool/rte_mempool.c | 31 ++++++++++++++++++-------------
 1 file changed, 18 insertions(+), 13 deletions(-)

-- 
2.30.2

[PATCH v2 1/2] mempool: fix rte_errno in rte_mempool_create_empty

[Ariel Otilibili]

When returning from rte_mempool_set_ops_byname(), rte_errno is not set
for error exits.

The API requires rte_errno to be set in that case.

Bugzilla ID: 1559
Fixes: c2c6b2f41305 ("mempool: fix default ops for an empty mempool")
Link: https://doc.dpdk.org/api/rte__mempool_8h.html#a82e301ee33ed7a263ceb4582655dc3ea
Signed-off-by: Ariel Otilibili <ariel.otilibili@6wind.com>
---
 lib/mempool/rte_mempool.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/lib/mempool/rte_mempool.c b/lib/mempool/rte_mempool.c
index d8e39e5c2072..1e4f24783c0b 100644
--- a/lib/mempool/rte_mempool.c
+++ b/lib/mempool/rte_mempool.c
@@ -928,8 +928,10 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 	else
 		ret = rte_mempool_set_ops_byname(mp, "ring_mp_mc", NULL);
 
-	if (ret)
+	if (ret) {
+		rte_errno = -ret;
 		goto exit_unlock;
+	}
 
 	/*
 	 * local_cache pointer is set even if cache_size is zero.
-- 
2.30.2

[PATCH v2 2/2] mempool: make rte_mempool_create_empty a single-exit

[Ariel Otilibili]

For properly setting rte_errno, and exiting rte_mempool_create_empty()
from a single place.

Bugzilla ID: 1559
Signed-off-by: Ariel Otilibili <ariel.otilibili@6wind.com>
---
 lib/mempool/rte_mempool.c | 27 +++++++++++++++------------
 1 file changed, 15 insertions(+), 12 deletions(-)

diff --git a/lib/mempool/rte_mempool.c b/lib/mempool/rte_mempool.c
index 1e4f24783c0b..3f9a4a1771d3 100644
--- a/lib/mempool/rte_mempool.c
+++ b/lib/mempool/rte_mempool.c
@@ -831,20 +831,20 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 	/* asked for zero items */
 	if (n == 0) {
 		rte_errno = EINVAL;
-		return NULL;
+		goto exit;
 	}
 
 	/* asked cache too big */
 	if (cache_size > RTE_MEMPOOL_CACHE_MAX_SIZE ||
 	    CALC_CACHE_FLUSHTHRESH(cache_size) > n) {
 		rte_errno = EINVAL;
-		return NULL;
+		goto exit;
 	}
 
 	/* enforce only user flags are passed by the application */
 	if ((flags & ~RTE_MEMPOOL_VALID_USER_FLAGS) != 0) {
 		rte_errno = EINVAL;
-		return NULL;
+		goto exit;
 	}
 
 	/*
@@ -860,7 +860,7 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 	/* calculate mempool object sizes. */
 	if (!rte_mempool_calc_obj_size(elt_size, flags, &objsz)) {
 		rte_errno = EINVAL;
-		return NULL;
+		goto exit;
 	}
 
 	rte_mcfg_mempool_write_lock();
@@ -877,7 +877,7 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 	te = rte_zmalloc("MEMPOOL_TAILQ_ENTRY", sizeof(*te), 0);
 	if (te == NULL) {
 		RTE_MEMPOOL_LOG(ERR, "Cannot allocate tailq entry!");
-		goto exit_unlock;
+		goto unlock;
 	}
 
 	mempool_size = RTE_MEMPOOL_HEADER_SIZE(mp, cache_size);
@@ -887,12 +887,12 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 	ret = snprintf(mz_name, sizeof(mz_name), RTE_MEMPOOL_MZ_FORMAT, name);
 	if (ret < 0 || ret >= (int)sizeof(mz_name)) {
 		rte_errno = ENAMETOOLONG;
-		goto exit_unlock;
+		goto unlock;
 	}
 
 	mz = rte_memzone_reserve(mz_name, mempool_size, socket_id, mz_flags);
 	if (mz == NULL)
-		goto exit_unlock;
+		goto unlock;
 
 	/* init the mempool structure */
 	mp = mz->addr;
@@ -900,7 +900,7 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 	ret = strlcpy(mp->name, name, sizeof(mp->name));
 	if (ret < 0 || ret >= (int)sizeof(mp->name)) {
 		rte_errno = ENAMETOOLONG;
-		goto exit_unlock;
+		goto unlock;
 	}
 	mp->mz = mz;
 	mp->size = n;
@@ -930,7 +930,7 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 
 	if (ret) {
 		rte_errno = -ret;
-		goto exit_unlock;
+		goto unlock;
 	}
 
 	/*
@@ -956,13 +956,16 @@ rte_mempool_create_empty(const char *name, unsigned n, unsigned elt_size,
 
 	rte_mempool_trace_create_empty(name, n, elt_size, cache_size,
 		private_data_size, flags, mp);
-	return mp;
+	goto exit;
 
-exit_unlock:
+unlock:
 	rte_mcfg_mempool_write_unlock();
 	rte_free(te);
 	rte_mempool_free(mp);
-	return NULL;
+	mp = NULL;
+
+exit:
+	return mp;
 }
 
 /* create the mempool */
-- 
2.30.2
<