[ovs-dev,v5,5/6] netdev-dpdk: Reword mp_size as n_mbufs.

Rename mp_size as n_mbufs in dpdk_mp structure.
This parameter is passed to rte mempool creation functions
and is meant to contain the number of elements inside
the requested mempool.

CC: Ciara Loftus <ciara.loftus@intel.com>
CC: Kevin Traynor <ktraynor@redhat.com>
CC: Aaron Conole <aconole@redhat.com>
Signed-off-by: Antonio Fischetti <antonio.fischetti@intel.com>
---
 lib/netdev-dpdk.c | 18 +++++++++---------
 1 file changed, 9 insertions(+), 9 deletions(-)

>From: ovs-dev-bounces@openvswitch.org [mailto:ovs-dev-bounces@openvswitch.org]
>On Behalf Of antonio.fischetti@intel.com
>Sent: Wednesday, October 11, 2017 5:01 PM
>To: dev@openvswitch.org
>Subject: [ovs-dev] [PATCH v5 5/6] netdev-dpdk: Reword mp_size as n_mbufs.
>
>Rename mp_size as n_mbufs in dpdk_mp structure.
>This parameter is passed to rte mempool creation functions
>and is meant to contain the number of elements inside
>the requested mempool.

As previously mentioned, I don't believe that this patch should be part of the 'fix management of pre-existing mempools' patchset, since it's a cosmetic change, rather than an actual fix.

Apart from that, I don't really see a need for this change - I think 'mp_size' is sufficiently descriptive.

Thanks,
Mark

>
>CC: Ciara Loftus <ciara.loftus@intel.com>
>CC: Kevin Traynor <ktraynor@redhat.com>
>CC: Aaron Conole <aconole@redhat.com>
>Signed-off-by: Antonio Fischetti <antonio.fischetti@intel.com>
>---
> lib/netdev-dpdk.c | 18 +++++++++---------
> 1 file changed, 9 insertions(+), 9 deletions(-)
>
>diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
>index c451bc9..f67c311 100644
>--- a/lib/netdev-dpdk.c
>+++ b/lib/netdev-dpdk.c
>@@ -308,7 +308,7 @@ struct dpdk_mp {
>     int mtu;
>     int socket_id;
>     char if_name[IFNAMSIZ];
>-    unsigned mp_size;
>+    unsigned n_mbufs;   /* Number of mbufs inside the mempool. */
>     struct ovs_list list_node OVS_GUARDED_BY(dpdk_mp_mutex);
> };
>
>@@ -500,7 +500,7 @@ dpdk_mp_name(struct dpdk_mp *dmp)
>     uint32_t h = hash_string(dmp->if_name, 0);
>     char *mp_name = xcalloc(RTE_MEMPOOL_NAMESIZE, sizeof *mp_name);
>     int ret = snprintf(mp_name, RTE_MEMPOOL_NAMESIZE, "ovs_%x_%d_%d_%u",
>-                       h, dmp->socket_id, dmp->mtu, dmp->mp_size);
>+                       h, dmp->socket_id, dmp->mtu, dmp->n_mbufs);
>     ovs_assert(ret >= 0 && ret < RTE_MEMPOOL_NAMESIZE);
>     return mp_name;
> }
>@@ -518,13 +518,13 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
>*mp_exists)
>     ovs_strzcpy(dmp->if_name, dev->up.name, IFNAMSIZ);
>
>     /*
>-     * XXX: rough estimation of memory required for port:
>+     * XXX: rough estimation of number of mbufs required for this port:
>      * <packets required to fill the device rxqs>
>      * + <packets that could be stuck on other ports txqs>
>      * + <packets in the pmd threads>
>      * + <additional memory for corner cases>
>      */
>-    dmp->mp_size = dev->requested_n_rxq * dev->requested_rxq_size
>+    dmp->n_mbufs = dev->requested_n_rxq * dev->requested_rxq_size
>             + dev->requested_n_txq * dev->requested_txq_size
>             + MIN(RTE_MAX_LCORE, dev->requested_n_rxq) * NETDEV_MAX_BURST
>             + MIN_NB_MBUF;
>@@ -534,11 +534,11 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
>*mp_exists)
>
>         VLOG_DBG("Requesting a mempool of %u mbufs for netdev %s "
>                  "with %d Rx and %d Tx queues, socket id:%d.",
>-                 dmp->mp_size, dev->up.name,
>+                 dmp->n_mbufs, dev->up.name,
>                  dev->requested_n_rxq, dev->requested_n_txq,
>                  dev->requested_socket_id);
>
>-        dmp->mp = rte_pktmbuf_pool_create(mp_name, dmp->mp_size,
>+        dmp->mp = rte_pktmbuf_pool_create(mp_name, dmp->n_mbufs,
>                                           MP_CACHE_SZ,
>                                           sizeof (struct dp_packet)
>                                                  - sizeof (struct rte_mbuf),
>@@ -547,7 +547,7 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
>*mp_exists)
>                                           dmp->socket_id);
>         if (dmp->mp) {
>             VLOG_DBG("Allocated \"%s\" mempool with %u mbufs", mp_name,
>-                     dmp->mp_size);
>+                     dmp->n_mbufs);
>             /* rte_pktmbuf_pool_create has done some initialization of the
>              * rte_mbuf part of each dp_packet. Some OvS specific fields
>              * of the packet still need to be initialized by
>@@ -565,14 +565,14 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
>*mp_exists)
>             *mp_exists = true;
>         } else {
>             VLOG_ERR("Failed mempool \"%s\" create request of %u mbufs",
>-                     mp_name, dmp->mp_size);
>+                     mp_name, dmp->n_mbufs);
>         }
>         free(mp_name);
>         if (dmp->mp) {
>             return dmp;
>         }
>     } while (!(*mp_exists) &&
>-            (rte_errno == ENOMEM && (dmp->mp_size /= 2) >= MIN_NB_MBUF));
>+            (rte_errno == ENOMEM && (dmp->n_mbufs /= 2) >= MIN_NB_MBUF));
>
>     rte_free(dmp);
>     return NULL;
>--
>2.4.11
>
>_______________________________________________
>dev mailing list
>dev@openvswitch.org
>https://mail.openvswitch.org/mailman/listinfo/ovs-dev

> -----Original Message-----
> From: Kavanagh, Mark B
> Sent: Friday, October 13, 2017 3:48 PM
> To: Fischetti, Antonio <antonio.fischetti@intel.com>; dev@openvswitch.org
> Subject: RE: [ovs-dev] [PATCH v5 5/6] netdev-dpdk: Reword mp_size as n_mbufs.
> 
> >From: ovs-dev-bounces@openvswitch.org [mailto:ovs-dev-bounces@openvswitch.org]
> >On Behalf Of antonio.fischetti@intel.com
> >Sent: Wednesday, October 11, 2017 5:01 PM
> >To: dev@openvswitch.org
> >Subject: [ovs-dev] [PATCH v5 5/6] netdev-dpdk: Reword mp_size as n_mbufs.
> >
> >Rename mp_size as n_mbufs in dpdk_mp structure.
> >This parameter is passed to rte mempool creation functions
> >and is meant to contain the number of elements inside
> >the requested mempool.
> 
> As previously mentioned, I don't believe that this patch should be part of the
> 'fix management of pre-existing mempools' patchset, since it's a cosmetic
> change, rather than an actual fix.
> 
> Apart from that, I don't really see a need for this change - I think 'mp_size'
> is sufficiently descriptive.

[Antonio] I'm proposing to reword mp_size because that
would mean "mempool size" to me, when instead it stores a 
number of mbufs. So it's a change similar to adding comments,
the purpose is to make code more readable.


> 
> Thanks,
> Mark
> 
> >
> >CC: Ciara Loftus <ciara.loftus@intel.com>
> >CC: Kevin Traynor <ktraynor@redhat.com>
> >CC: Aaron Conole <aconole@redhat.com>
> >Signed-off-by: Antonio Fischetti <antonio.fischetti@intel.com>
> >---
> > lib/netdev-dpdk.c | 18 +++++++++---------
> > 1 file changed, 9 insertions(+), 9 deletions(-)
> >
> >diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
> >index c451bc9..f67c311 100644
> >--- a/lib/netdev-dpdk.c
> >+++ b/lib/netdev-dpdk.c
> >@@ -308,7 +308,7 @@ struct dpdk_mp {
> >     int mtu;
> >     int socket_id;
> >     char if_name[IFNAMSIZ];
> >-    unsigned mp_size;
> >+    unsigned n_mbufs;   /* Number of mbufs inside the mempool. */
> >     struct ovs_list list_node OVS_GUARDED_BY(dpdk_mp_mutex);
> > };
> >
> >@@ -500,7 +500,7 @@ dpdk_mp_name(struct dpdk_mp *dmp)
> >     uint32_t h = hash_string(dmp->if_name, 0);
> >     char *mp_name = xcalloc(RTE_MEMPOOL_NAMESIZE, sizeof *mp_name);
> >     int ret = snprintf(mp_name, RTE_MEMPOOL_NAMESIZE, "ovs_%x_%d_%d_%u",
> >-                       h, dmp->socket_id, dmp->mtu, dmp->mp_size);
> >+                       h, dmp->socket_id, dmp->mtu, dmp->n_mbufs);
> >     ovs_assert(ret >= 0 && ret < RTE_MEMPOOL_NAMESIZE);
> >     return mp_name;
> > }
> >@@ -518,13 +518,13 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
> >*mp_exists)
> >     ovs_strzcpy(dmp->if_name, dev->up.name, IFNAMSIZ);
> >
> >     /*
> >-     * XXX: rough estimation of memory required for port:
> >+     * XXX: rough estimation of number of mbufs required for this port:
> >      * <packets required to fill the device rxqs>
> >      * + <packets that could be stuck on other ports txqs>
> >      * + <packets in the pmd threads>
> >      * + <additional memory for corner cases>
> >      */
> >-    dmp->mp_size = dev->requested_n_rxq * dev->requested_rxq_size
> >+    dmp->n_mbufs = dev->requested_n_rxq * dev->requested_rxq_size
> >             + dev->requested_n_txq * dev->requested_txq_size
> >             + MIN(RTE_MAX_LCORE, dev->requested_n_rxq) * NETDEV_MAX_BURST
> >             + MIN_NB_MBUF;
> >@@ -534,11 +534,11 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
> >*mp_exists)
> >
> >         VLOG_DBG("Requesting a mempool of %u mbufs for netdev %s "
> >                  "with %d Rx and %d Tx queues, socket id:%d.",
> >-                 dmp->mp_size, dev->up.name,
> >+                 dmp->n_mbufs, dev->up.name,
> >                  dev->requested_n_rxq, dev->requested_n_txq,
> >                  dev->requested_socket_id);
> >
> >-        dmp->mp = rte_pktmbuf_pool_create(mp_name, dmp->mp_size,
> >+        dmp->mp = rte_pktmbuf_pool_create(mp_name, dmp->n_mbufs,
> >                                           MP_CACHE_SZ,
> >                                           sizeof (struct dp_packet)
> >                                                  - sizeof (struct rte_mbuf),
> >@@ -547,7 +547,7 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
> >*mp_exists)
> >                                           dmp->socket_id);
> >         if (dmp->mp) {
> >             VLOG_DBG("Allocated \"%s\" mempool with %u mbufs", mp_name,
> >-                     dmp->mp_size);
> >+                     dmp->n_mbufs);
> >             /* rte_pktmbuf_pool_create has done some initialization of the
> >              * rte_mbuf part of each dp_packet. Some OvS specific fields
> >              * of the packet still need to be initialized by
> >@@ -565,14 +565,14 @@ dpdk_mp_create(struct netdev_dpdk *dev, int mtu, bool
> >*mp_exists)
> >             *mp_exists = true;
> >         } else {
> >             VLOG_ERR("Failed mempool \"%s\" create request of %u mbufs",
> >-                     mp_name, dmp->mp_size);
> >+                     mp_name, dmp->n_mbufs);
> >         }
> >         free(mp_name);
> >         if (dmp->mp) {
> >             return dmp;
> >         }
> >     } while (!(*mp_exists) &&
> >-            (rte_errno == ENOMEM && (dmp->mp_size /= 2) >= MIN_NB_MBUF));
> >+            (rte_errno == ENOMEM && (dmp->n_mbufs /= 2) >= MIN_NB_MBUF));
> >
> >     rte_free(dmp);
> >     return NULL;
> >--
> >2.4.11
> >
> >_______________________________________________
> >dev mailing list
> >dev@openvswitch.org
> >https://mail.openvswitch.org/mailman/listinfo/ovs-dev