[ovs-dev,v8,03/13] dp-packet: Fix allocated size on DPDK init.

Message ID 1528734090-220990-4-git-send-email-tiago.lam@intel.com
State Superseded
Headers show
Series
  • Support multi-segment mbufs
Related show

Commit Message

Lam, Tiago June 11, 2018, 4:21 p.m.
When enabled with DPDK OvS deals with two types of packets, the ones
coming from the mempool and the ones locally created by OvS - which are
copied to mempool mbufs before output. In the latter, the space is
allocated from the system, while in the former the mbufs are allocated
from a mempool, which takes care of initialising them appropriately.

In the current implementation, during mempool's initialisation of mbufs,
dp_packet_set_allocated() is called from dp_packet_init_dpdk() without
considering that the allocated space, in the case of multi-segment
mbufs, might be greater than a single mbuf.  Furthermore, given that
dp_packet_init_dpdk() is on the code path that's called upon mempool's
initialisation, a call to dp_packet_set_allocated() is redundant, since
mempool takes care of initialising it.

To fix this, dp_packet_set_allocated() is no longer called after
initialisation of a mempool, only in dp_packet_init__(), which is still
called by OvS when initialising locally created packets.

Signed-off-by: Tiago Lam <tiago.lam@intel.com>
---
 lib/dp-packet.c   | 3 +--
 lib/dp-packet.h   | 2 +-
 lib/netdev-dpdk.c | 2 +-
 3 files changed, 3 insertions(+), 4 deletions(-)

Comments

Eelco Chaudron June 18, 2018, 11:26 a.m. | #1
On 11 Jun 2018, at 18:21, Tiago Lam wrote:

> When enabled with DPDK OvS deals with two types of packets, the ones
> coming from the mempool and the ones locally created by OvS - which 
> are
> copied to mempool mbufs before output. In the latter, the space is
> allocated from the system, while in the former the mbufs are allocated
> from a mempool, which takes care of initialising them appropriately.
>
> In the current implementation, during mempool's initialisation of 
> mbufs,
> dp_packet_set_allocated() is called from dp_packet_init_dpdk() without
> considering that the allocated space, in the case of multi-segment
> mbufs, might be greater than a single mbuf.  Furthermore, given that
> dp_packet_init_dpdk() is on the code path that's called upon mempool's
> initialisation, a call to dp_packet_set_allocated() is redundant, 
> since
> mempool takes care of initialising it.
>
> To fix this, dp_packet_set_allocated() is no longer called after
> initialisation of a mempool, only in dp_packet_init__(), which is 
> still
> called by OvS when initialising locally created packets.
>

LGTM,

Acked-by: Eelco Chaudron <echaudro@redhat.com>

> Signed-off-by: Tiago Lam <tiago.lam@intel.com>
> ---
>  lib/dp-packet.c   | 3 +--
>  lib/dp-packet.h   | 2 +-
>  lib/netdev-dpdk.c | 2 +-
>  3 files changed, 3 insertions(+), 4 deletions(-)
>
> diff --git a/lib/dp-packet.c b/lib/dp-packet.c
> index 443c225..782e7c2 100644
> --- a/lib/dp-packet.c
> +++ b/lib/dp-packet.c
> @@ -99,9 +99,8 @@ dp_packet_use_const(struct dp_packet *b, const void 
> *data, size_t size)
>   * buffer.  Here, non-transient ovs dp-packet fields are initialized 
> for
>   * packets that are part of a DPDK memory pool. */
>  void
> -dp_packet_init_dpdk(struct dp_packet *b, size_t allocated)
> +dp_packet_init_dpdk(struct dp_packet *b)
>  {
> -    dp_packet_set_allocated(b, allocated);
>      b->source = DPBUF_DPDK;
>  }
>
> diff --git a/lib/dp-packet.h b/lib/dp-packet.h
> index 82e45ad..4c104b6 100644
> --- a/lib/dp-packet.h
> +++ b/lib/dp-packet.h
> @@ -114,7 +114,7 @@ void dp_packet_use(struct dp_packet *, void *, 
> size_t);
>  void dp_packet_use_stub(struct dp_packet *, void *, size_t);
>  void dp_packet_use_const(struct dp_packet *, const void *, size_t);
>
> -void dp_packet_init_dpdk(struct dp_packet *, size_t allocated);
> +void dp_packet_init_dpdk(struct dp_packet *);
>
>  void dp_packet_init(struct dp_packet *, size_t);
>  void dp_packet_uninit(struct dp_packet *);
> diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
> index 468ab36..f546507 100644
> --- a/lib/netdev-dpdk.c
> +++ b/lib/netdev-dpdk.c
> @@ -519,7 +519,7 @@ ovs_rte_pktmbuf_init(struct rte_mempool *mp 
> OVS_UNUSED,
>  {
>      struct rte_mbuf *pkt = _p;
>
> -    dp_packet_init_dpdk((struct dp_packet *) pkt, pkt->buf_len);
> +    dp_packet_init_dpdk((struct dp_packet *) pkt);
>  }
>
>  static int
> -- 
> 2.7.4

Patch

diff --git a/lib/dp-packet.c b/lib/dp-packet.c
index 443c225..782e7c2 100644
--- a/lib/dp-packet.c
+++ b/lib/dp-packet.c
@@ -99,9 +99,8 @@  dp_packet_use_const(struct dp_packet *b, const void *data, size_t size)
  * buffer.  Here, non-transient ovs dp-packet fields are initialized for
  * packets that are part of a DPDK memory pool. */
 void
-dp_packet_init_dpdk(struct dp_packet *b, size_t allocated)
+dp_packet_init_dpdk(struct dp_packet *b)
 {
-    dp_packet_set_allocated(b, allocated);
     b->source = DPBUF_DPDK;
 }
 
diff --git a/lib/dp-packet.h b/lib/dp-packet.h
index 82e45ad..4c104b6 100644
--- a/lib/dp-packet.h
+++ b/lib/dp-packet.h
@@ -114,7 +114,7 @@  void dp_packet_use(struct dp_packet *, void *, size_t);
 void dp_packet_use_stub(struct dp_packet *, void *, size_t);
 void dp_packet_use_const(struct dp_packet *, const void *, size_t);
 
-void dp_packet_init_dpdk(struct dp_packet *, size_t allocated);
+void dp_packet_init_dpdk(struct dp_packet *);
 
 void dp_packet_init(struct dp_packet *, size_t);
 void dp_packet_uninit(struct dp_packet *);
diff --git a/lib/netdev-dpdk.c b/lib/netdev-dpdk.c
index 468ab36..f546507 100644
--- a/lib/netdev-dpdk.c
+++ b/lib/netdev-dpdk.c
@@ -519,7 +519,7 @@  ovs_rte_pktmbuf_init(struct rte_mempool *mp OVS_UNUSED,
 {
     struct rte_mbuf *pkt = _p;
 
-    dp_packet_init_dpdk((struct dp_packet *) pkt, pkt->buf_len);
+    dp_packet_init_dpdk((struct dp_packet *) pkt);
 }
 
 static int