From: Olivier Matz <olivier.matz@6wind.com>
To: dev@dpdk.org
Subject: [dpdk-dev] [RFC 3/8] mbuf: set mbuf fields while in pool
Date: Tue, 24 Jan 2017 16:19:28 +0100 [thread overview]
Message-ID: <1485271173-13408-4-git-send-email-olivier.matz@6wind.com> (raw)
In-Reply-To: <1485271173-13408-1-git-send-email-olivier.matz@6wind.com>
Set the value of m->refcnt to 1, m->nb_segs to 1 and m->next
to NULL when the mbuf is stored inside the mempool (unused).
This is done in rte_pktmbuf_prefree_seg(), before freeing or
recycling a mbuf.
Before this patch, the value of m->refcnt was expected to be 0
while in pool.
The objectives are:
- to avoid drivers to set m->next to NULL in the early Rx path, since
this field is in the second 64B of the mbuf and its access could
trigger a cache miss
- rationalize the behavior of raw_alloc/raw_free: one is now the
symmetric of the other, and refcnt is never changed in these functions.
Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
drivers/net/mlx5/mlx5_rxtx.c | 5 ++---
drivers/net/mpipe/mpipe_tilegx.c | 1 +
lib/librte_mbuf/rte_mbuf.c | 2 ++
lib/librte_mbuf/rte_mbuf.h | 45 +++++++++++++++++++++++++++++-----------
4 files changed, 38 insertions(+), 15 deletions(-)
diff --git a/drivers/net/mlx5/mlx5_rxtx.c b/drivers/net/mlx5/mlx5_rxtx.c
index a518a42..294dfde 100644
--- a/drivers/net/mlx5/mlx5_rxtx.c
+++ b/drivers/net/mlx5/mlx5_rxtx.c
@@ -1327,7 +1327,8 @@ mlx5_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
while (pkt != seg) {
assert(pkt != (*rxq->elts)[idx]);
rep = NEXT(pkt);
- rte_mbuf_refcnt_set(pkt, 0);
+ NEXT(pkt) = NULL;
+ NB_SEGS(pkt) = 1;
rte_mbuf_raw_free(pkt);
pkt = rep;
}
@@ -1338,13 +1339,11 @@ mlx5_rx_burst(void *dpdk_rxq, struct rte_mbuf **pkts, uint16_t pkts_n)
len = mlx5_rx_poll_len(rxq, cqe, cqe_cnt,
&rss_hash_res);
if (!len) {
- rte_mbuf_refcnt_set(rep, 0);
rte_mbuf_raw_free(rep);
break;
}
if (unlikely(len == -1)) {
/* RX error, packet is likely too large. */
- rte_mbuf_refcnt_set(rep, 0);
rte_mbuf_raw_free(rep);
++rxq->stats.idropped;
goto skip;
diff --git a/drivers/net/mpipe/mpipe_tilegx.c b/drivers/net/mpipe/mpipe_tilegx.c
index eedc0b3..560ffe9 100644
--- a/drivers/net/mpipe/mpipe_tilegx.c
+++ b/drivers/net/mpipe/mpipe_tilegx.c
@@ -548,6 +548,7 @@ mpipe_recv_flush_stack(struct mpipe_dev_priv *priv)
mbuf->packet_type = 0;
mbuf->data_len = 0;
mbuf->pkt_len = 0;
+ mbuf->next = NULL;
rte_mbuf_raw_free(mbuf);
}
diff --git a/lib/librte_mbuf/rte_mbuf.c b/lib/librte_mbuf/rte_mbuf.c
index 72ad91e..0acc810 100644
--- a/lib/librte_mbuf/rte_mbuf.c
+++ b/lib/librte_mbuf/rte_mbuf.c
@@ -145,6 +145,8 @@ rte_pktmbuf_init(struct rte_mempool *mp,
m->pool = mp;
m->nb_segs = 1;
m->port = 0xff;
+ rte_mbuf_refcnt_set(m, 1);
+ m->next = NULL;
}
/* helper to create a mbuf pool */
diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h
index 8ff2290..bbd0700 100644
--- a/lib/librte_mbuf/rte_mbuf.h
+++ b/lib/librte_mbuf/rte_mbuf.h
@@ -766,6 +766,11 @@ rte_mbuf_sanity_check(const struct rte_mbuf *m, int is_header);
* initializing all the required fields. See rte_pktmbuf_reset().
* For standard needs, prefer rte_pktmbuf_alloc().
*
+ * The caller can expect that the following fields of the mbuf structure
+ * are initialized: buf_addr, buf_physaddr, buf_len, refcnt=1, nb_segs=1,
+ * next=NULL, pool, priv_size. The other fields must be initialized
+ * by the caller.
+ *
* @param mp
* The mempool from which mbuf is allocated.
* @return
@@ -780,8 +785,9 @@ static inline struct rte_mbuf *rte_mbuf_raw_alloc(struct rte_mempool *mp)
if (rte_mempool_get(mp, &mb) < 0)
return NULL;
m = (struct rte_mbuf *)mb;
- RTE_ASSERT(rte_mbuf_refcnt_read(m) == 0);
- rte_mbuf_refcnt_set(m, 1);
+ RTE_ASSERT(rte_mbuf_refcnt_read(m) == 1);
+ RTE_ASSERT(m->next == NULL);
+ RTE_ASSERT(m->nb_segs == 1);
__rte_mbuf_sanity_check(m, 0);
return m;
@@ -790,8 +796,13 @@ static inline struct rte_mbuf *rte_mbuf_raw_alloc(struct rte_mempool *mp)
/**
* Put mbuf back into its original mempool.
*
- * The caller must ensure that the mbuf is direct and that the
- * reference counter is 0.
+ * The caller must ensure that the mbuf is direct and properly
+ * reinitialized (refcnt=1, next=NULL, nb_segs=1), as done by
+ * rte_pktmbuf_prefree_seg().
+ *
+ * This function should be used with care, when optimization is
+ * required. For standard needs, prefer rte_pktmbuf_free() or
+ * rte_pktmbuf_free_seg().
*
* @param m
* The mbuf to be freed.
@@ -800,13 +811,16 @@ static inline void __attribute__((always_inline))
rte_mbuf_raw_free(struct rte_mbuf *m)
{
RTE_ASSERT(RTE_MBUF_DIRECT(m));
- RTE_ASSERT(rte_mbuf_refcnt_read(m) == 0);
+ RTE_ASSERT(rte_mbuf_refcnt_read(m) == 1);
+ RTE_ASSERT(m->next == NULL);
+ RTE_ASSERT(m->nb_segs == 1);
+ __rte_mbuf_sanity_check(m, 0);
rte_mempool_put(m->pool, m);
}
/* compat with older versions */
__rte_deprecated
-static inline void __attribute__((always_inline))
+static inline void
__rte_mbuf_raw_free(struct rte_mbuf *m)
{
rte_mbuf_raw_free(m);
@@ -1218,8 +1232,12 @@ static inline void rte_pktmbuf_detach(struct rte_mbuf *m)
m->data_len = 0;
m->ol_flags = 0;
- if (rte_mbuf_refcnt_update(md, -1) == 0)
+ if (rte_mbuf_refcnt_update(md, -1) == 0) {
+ md->next = NULL;
+ md->nb_segs = 1;
+ rte_mbuf_refcnt_set(md, 1);
rte_mbuf_raw_free(md);
+ }
}
/**
@@ -1243,9 +1261,14 @@ rte_pktmbuf_prefree_seg(struct rte_mbuf *m)
__rte_mbuf_sanity_check(m, 0);
if (likely(rte_mbuf_refcnt_update(m, -1) == 0)) {
- /* if this is an indirect mbuf, it is detached. */
- if (RTE_MBUF_INDIRECT(m))
+ if (RTE_MBUF_INDIRECT(m)) {
rte_pktmbuf_detach(m);
+ /* next, nb_segs, refcnt are reset */
+ } else {
+ m->next = NULL;
+ m->nb_segs = 1;
+ rte_mbuf_refcnt_set(m, 1);
+ }
return m;
}
return NULL;
@@ -1272,10 +1295,8 @@ static inline void __attribute__((always_inline))
rte_pktmbuf_free_seg(struct rte_mbuf *m)
{
m = rte_pktmbuf_prefree_seg(m);
- if (likely(m != NULL)) {
- m->next = NULL;
+ if (likely(m != NULL))
rte_mbuf_raw_free(m);
- }
}
/**
--
2.8.1
next prev parent reply other threads:[~2017-01-24 15:22 UTC|newest]
Thread overview: 155+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-01-24 15:19 [dpdk-dev] [RFC 0/8] mbuf: structure reorganization Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 1/8] mbuf: make segment prefree function public Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 2/8] mbuf: make raw free " Olivier Matz
2017-01-24 15:19 ` Olivier Matz [this message]
2017-01-24 15:50 ` [dpdk-dev] [RFC 3/8] mbuf: set mbuf fields while in pool Bruce Richardson
2017-02-28 14:51 ` Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 4/8] net: don't touch mbuf next or nb segs on Rx Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 5/8] mbuf: make rearm data address naturally aligned Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 6/8] mbuf: use 2 bytes for port and nb segments Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 7/8] mbuf: move sequence number in second cache line Olivier Matz
2017-01-24 15:19 ` [dpdk-dev] [RFC 8/8] mbuf: add a timestamp field Olivier Matz
2017-01-24 15:59 ` [dpdk-dev] [RFC 0/8] mbuf: structure reorganization Bruce Richardson
2017-01-24 16:16 ` Olivier MATZ
2017-02-06 18:41 ` Ananyev, Konstantin
2017-02-09 16:20 ` Morten Brørup
2017-02-09 16:56 ` Ananyev, Konstantin
2017-02-16 13:48 ` Olivier Matz
2017-02-16 15:46 ` Bruce Richardson
2017-02-16 16:14 ` Olivier Matz
2017-02-21 14:20 ` Morten Brørup
2017-02-21 14:28 ` Bruce Richardson
2017-02-21 15:04 ` Olivier MATZ
2017-02-21 15:18 ` Bruce Richardson
2017-02-21 15:18 ` Morten Brørup
2017-02-19 19:04 ` Chilikin, Andrey
2017-02-21 9:53 ` Olivier MATZ
2017-02-16 17:26 ` Jan Blunck
2017-02-17 10:51 ` Olivier Matz
2017-02-17 12:49 ` Nélio Laranjeiro
2017-02-17 13:51 ` Jan Blunck
2017-02-18 5:48 ` Andrew Rybchenko
2017-02-17 13:38 ` Jan Blunck
2017-02-17 14:17 ` Olivier Matz
2017-02-17 18:42 ` Ananyev, Konstantin
2017-02-21 9:53 ` Olivier MATZ
2017-02-21 10:28 ` Ananyev, Konstantin
2017-02-20 9:27 ` Jan Blunck
2017-02-21 9:54 ` Olivier MATZ
2017-02-21 16:12 ` Jan Blunck
2017-02-21 16:38 ` Bruce Richardson
2017-02-21 17:04 ` Jan Blunck
2017-02-21 17:26 ` Ananyev, Konstantin
2017-02-21 19:17 ` Jan Blunck
2017-02-21 20:30 ` Ananyev, Konstantin
2017-02-21 21:51 ` Morten Brørup
2017-02-24 14:11 ` Olivier Matz
2017-02-24 14:00 ` Olivier Matz
2017-02-24 14:21 ` Bruce Richardson
2017-02-28 8:55 ` Jan Blunck
2017-02-28 9:05 ` Ananyev, Konstantin
2017-02-28 9:23 ` Olivier Matz
2017-02-28 9:33 ` Jan Blunck
2017-02-28 10:29 ` Ananyev, Konstantin
2017-02-28 10:50 ` Olivier Matz
2017-02-28 11:48 ` Ananyev, Konstantin
2017-02-28 12:28 ` Olivier Matz
2017-02-28 22:53 ` Ananyev, Konstantin
2017-03-02 16:46 ` Olivier Matz
2017-03-08 11:11 ` Ananyev, Konstantin
2017-03-20 9:00 ` Olivier Matz
2017-03-22 17:42 ` Ananyev, Konstantin
2017-03-24 8:35 ` Jerin Jacob
2017-03-24 13:35 ` Olivier Matz
2017-02-28 9:25 ` Jan Blunck
2017-02-19 23:45 ` Ananyev, Konstantin
2017-02-21 9:22 ` Morten Brørup
2017-02-21 9:54 ` Olivier MATZ
2017-03-08 9:41 ` [dpdk-dev] [PATCH 0/9] " Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 1/9] mbuf: make segment prefree function public Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 2/9] mbuf: make raw free " Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 3/9] mbuf: set mbuf fields while in pool Olivier Matz
2017-03-31 11:21 ` Bruce Richardson
2017-03-31 11:51 ` Ananyev, Konstantin
2017-03-08 9:41 ` [dpdk-dev] [PATCH 4/9] drivers/net: don't touch mbuf next or nb segs on Rx Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 5/9] mbuf: make rearm data address naturally aligned Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 6/9] mbuf: use 2 bytes for port and nb segments Olivier Matz
2017-03-08 9:41 ` [dpdk-dev] [PATCH 7/9] mbuf: move sequence number in second cache line Olivier Matz
2017-03-08 9:42 ` [dpdk-dev] [PATCH 8/9] mbuf: add a timestamp field Olivier Matz
2017-04-04 10:29 ` [dpdk-dev] [PATCH 0/2] reduce writes to mbuf in ixgbe vRX Konstantin Ananyev
2017-04-07 15:13 ` Ferruh Yigit
2017-04-07 15:44 ` Ferruh Yigit
2017-04-09 22:56 ` Ananyev, Konstantin
2017-04-04 10:29 ` [dpdk-dev] [PATCH 1/2] net/ixgbe: eliminate mbuf write on rearm Konstantin Ananyev
2017-04-10 15:59 ` [dpdk-dev] [PATCH v2 0/2] reduce writes to mbuf in ixgbe vRX Konstantin Ananyev
2017-04-10 16:17 ` Ferruh Yigit
2017-04-10 15:59 ` [dpdk-dev] [PATCH v2 1/2] net/ixgbe: eliminate mbuf write on rearm Konstantin Ananyev
2017-04-10 15:59 ` [dpdk-dev] [PATCH v2 2/2] net/ixgbe: remove option to disable offload flags Konstantin Ananyev
2017-04-04 10:29 ` [dpdk-dev] [PATCH " Konstantin Ananyev
2017-03-08 9:42 ` [dpdk-dev] [PATCH 9/9] mbuf: reorder VLAN tci and buffer len fields Olivier Matz
2017-03-29 15:56 ` [dpdk-dev] [PATCH 0/9] mbuf: structure reorganization Olivier Matz
2017-03-29 16:03 ` Morten Brørup
2017-03-29 20:09 ` Bruce Richardson
2017-03-30 9:31 ` Bruce Richardson
2017-03-30 12:02 ` Olivier Matz
2017-03-30 12:23 ` Bruce Richardson
2017-03-30 16:45 ` Ananyev, Konstantin
2017-03-30 16:47 ` Ananyev, Konstantin
2017-03-30 18:06 ` Ananyev, Konstantin
2017-03-31 8:41 ` Olivier Matz
2017-03-31 9:58 ` Ananyev, Konstantin
2017-03-31 1:00 ` Ananyev, Konstantin
2017-03-31 7:21 ` Morten Brørup
2017-03-31 8:26 ` Olivier Matz
2017-03-31 8:41 ` Bruce Richardson
2017-03-31 8:59 ` Olivier Matz
2017-03-31 9:18 ` Ananyev, Konstantin
2017-03-31 9:36 ` Olivier Matz
2017-04-03 16:15 ` Thomas Monjalon
2017-04-04 7:58 ` Olivier MATZ
2017-04-04 8:53 ` Bruce Richardson
2017-03-31 9:23 ` Bruce Richardson
2017-03-31 11:18 ` Nélio Laranjeiro
2017-03-30 14:54 ` Andrew Rybchenko
2017-03-30 15:12 ` Jerin Jacob
2017-04-04 16:27 ` [dpdk-dev] [PATCH v2 0/8] " Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 1/8] mbuf: make segment prefree function public Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 2/8] mbuf: make raw free " Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 3/8] mbuf: set mbuf fields while in pool Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 4/8] drivers/net: don't touch mbuf next or nb segs on Rx Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 5/8] mbuf: make rearm data address naturally aligned Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nb segments Olivier Matz
2017-04-06 5:45 ` Yuanhan Liu
2017-04-18 13:03 ` Olivier MATZ
2017-07-04 7:54 ` Wang, Zhihong
2017-07-10 8:00 ` Olivier Matz
2017-07-10 8:15 ` Morten Brørup
2017-07-11 13:25 ` Wiles, Keith
2017-07-11 13:30 ` Morten Brørup
2017-07-11 15:05 ` Thomas Monjalon
2017-07-11 15:23 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nbsegments Morten Brørup
2017-07-11 16:48 ` Wiles, Keith
2017-07-12 7:25 ` Morten Brørup
2017-07-12 9:02 ` Yang, Zhiyong
2017-07-12 9:50 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port andnbsegments Morten Brørup
2017-07-12 15:35 ` Stephen Hemminger
2017-07-12 15:57 ` Morten Brørup
2017-07-12 16:23 ` Thomas Monjalon
2017-07-12 18:20 ` Wiles, Keith
2017-07-21 15:03 ` Bruce Richardson
2017-07-12 15:34 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nbsegments Wiles, Keith
2017-07-11 13:34 ` [dpdk-dev] [PATCH v2 6/8] mbuf: use 2 bytes for port and nb segments Wiles, Keith
2017-07-11 13:46 ` Olivier MATZ
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 7/8] mbuf: move sequence number in second cache line Olivier Matz
2017-04-04 16:28 ` [dpdk-dev] [PATCH v2 8/8] mbuf: add a timestamp field Olivier Matz
2017-04-05 9:37 ` [dpdk-dev] [PATCH v2 0/8] mbuf: structure reorganization Thomas Monjalon
2017-04-05 9:46 ` Olivier MATZ
2017-04-05 9:48 ` Richardson, Bruce
2017-04-05 12:06 ` Ferruh Yigit
2017-04-14 13:10 ` Ferruh Yigit
2017-04-18 13:04 ` Olivier MATZ
2017-04-19 9:39 ` Thomas Monjalon
2017-04-19 12:28 ` Olivier MATZ
2017-04-19 12:56 ` Thomas Monjalon
2017-04-19 13:03 ` Ferruh Yigit
2017-04-19 13:12 ` Thomas Monjalon
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=1485271173-13408-4-git-send-email-olivier.matz@6wind.com \
--to=olivier.matz@6wind.com \
--cc=dev@dpdk.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).