[1/4] mbuf: detach mbuf with pinned external buffer
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Commit Message
Update detach routine to check the mbuf pool type.
Signed-off-by: Shahaf Shuler <shahafs@mellanox.com>
Signed-off-by: Viacheslav Ovsiienko <viacheslavo@mellanox.com>
---
lib/librte_mbuf/rte_mbuf.h | 59 ++++++++++++++++++++++++++++++++++++++++++----
1 file changed, 55 insertions(+), 4 deletions(-)
Comments
On Fri, 10 Jan 2020 17:56:59 +0000
Viacheslav Ovsiienko <viacheslavo@mellanox.com> wrote:
> +
> +static inline uint64_t
> +rte_mbuf_has_pinned_extbuf(const struct rte_mbuf *m)
> +{
> + if (RTE_MBUF_HAS_EXTBUF(m)) {
> + /*
> + * The mbuf has the external attached buffer,
> + * we should check the type of the memory pool where
> + * the mbuf was allocated from.
> + */
> + struct rte_pktmbuf_pool_private *priv =
> + (struct rte_pktmbuf_pool_private *)
> + rte_mempool_get_priv(m->pool);
> +
> + return priv->flags & RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF;
> + }
> + return 0;
> +}
New functions need to be marked experimental.
The return value should be boolean not uint64_t
Why does this need to be inlined (and thereby create new ABI burden)?
Also having it inline makes making pktmbuf_pool_private really private in future.
Hi, Stephen
Thanks a lot for the comment.
> -----Original Message-----
> From: Stephen Hemminger <stephen@networkplumber.org>
> Sent: Friday, January 10, 2020 20:24
> To: Slava Ovsiienko <viacheslavo@mellanox.com>
> Cc: dev@dpdk.org; Matan Azrad <matan@mellanox.com>; Raslan Darawsheh
> <rasland@mellanox.com>; Ori Kam <orika@mellanox.com>; Shahaf Shuler
> <shahafs@mellanox.com>
> Subject: Re: [dpdk-dev] [PATCH 1/4] mbuf: detach mbuf with pinned external
> buffer
>
> On Fri, 10 Jan 2020 17:56:59 +0000
> Viacheslav Ovsiienko <viacheslavo@mellanox.com> wrote:
>
> > +
> > +static inline uint64_t
> > +rte_mbuf_has_pinned_extbuf(const struct rte_mbuf *m) {
> > + if (RTE_MBUF_HAS_EXTBUF(m)) {
> > + /*
> > + * The mbuf has the external attached buffer,
> > + * we should check the type of the memory pool where
> > + * the mbuf was allocated from.
> > + */
> > + struct rte_pktmbuf_pool_private *priv =
> > + (struct rte_pktmbuf_pool_private *)
> > + rte_mempool_get_priv(m->pool);
> > +
> > + return priv->flags &
> RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF;
> > + }
> > + return 0;
> > +}
>
> New functions need to be marked experimental.
> The return value should be boolean not uint64_t
Will be fixed in v2.
>
> Why does this need to be inlined (and thereby create new ABI burden)?
> Also having it inline makes making pktmbuf_pool_private really private in
> future.
Due to performance reasons. This routine potentially might be used in datapath.
With best regards, Slava
> -----Original Message-----
> From: Stephen Hemminger <stephen@networkplumber.org>
> Sent: Friday, January 10, 2020 20:24
> To: Slava Ovsiienko <viacheslavo@mellanox.com>
> Cc: dev@dpdk.org; Matan Azrad <matan@mellanox.com>; Raslan Darawsheh
> <rasland@mellanox.com>; Ori Kam <orika@mellanox.com>; Shahaf Shuler
> <shahafs@mellanox.com>
> Subject: Re: [dpdk-dev] [PATCH 1/4] mbuf: detach mbuf with pinned external
> buffer
>
> On Fri, 10 Jan 2020 17:56:59 +0000
> Viacheslav Ovsiienko <viacheslavo@mellanox.com> wrote:
>
> > +
> > +static inline uint64_t
> > +rte_mbuf_has_pinned_extbuf(const struct rte_mbuf *m) {
> > + if (RTE_MBUF_HAS_EXTBUF(m)) {
> > + /*
> > + * The mbuf has the external attached buffer,
> > + * we should check the type of the memory pool where
> > + * the mbuf was allocated from.
> > + */
> > + struct rte_pktmbuf_pool_private *priv =
> > + (struct rte_pktmbuf_pool_private *)
> > + rte_mempool_get_priv(m->pool);
> > +
> > + return priv->flags &
> RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF;
> > + }
> > + return 0;
> > +}
>
> New functions need to be marked experimental.
>
> The return value should be boolean not uint64_t
I intentionally avoided the "bool" in v1. This is not native C type,
requires the extra header (stdbool.h at least) and has poor portability -
we would run into conflict with AltiVec - "bool" becomes reserved keyword.
So, I'm going to change return value type to uint32_t (as private flag field has).
With best regards, Slava
@@ -306,6 +306,41 @@ struct rte_pktmbuf_pool_private {
uint32_t flags; /**< reserved for future use. */
};
+/**
+ * When set pktmbuf mempool will hold only mbufs with pinned external
+ * buffer. The external buffer will be attached on the mbuf at the
+ * memory pool creation and will never be detached by the mbuf free calls.
+ * mbuf should not contain any room for data after the mbuf structure.
+ */
+#define RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF (1 << 0)
+
+/**
+ * Returns TRUE if given mbuf has an pinned external buffer, or FALSE
+ * otherwise. The pinned external buffer is allocated at pool creation
+ * time and should not be freed.
+ *
+ * External buffer is a user-provided anonymous buffer.
+ */
+#define RTE_MBUF_HAS_PINNED_EXTBUF(mb) rte_mbuf_has_pinned_extbuf(mb)
+
+static inline uint64_t
+rte_mbuf_has_pinned_extbuf(const struct rte_mbuf *m)
+{
+ if (RTE_MBUF_HAS_EXTBUF(m)) {
+ /*
+ * The mbuf has the external attached buffer,
+ * we should check the type of the memory pool where
+ * the mbuf was allocated from.
+ */
+ struct rte_pktmbuf_pool_private *priv =
+ (struct rte_pktmbuf_pool_private *)
+ rte_mempool_get_priv(m->pool);
+
+ return priv->flags & RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF;
+ }
+ return 0;
+}
+
#ifdef RTE_LIBRTE_MBUF_DEBUG
/** check mbuf type in debug mode */
@@ -571,7 +606,8 @@ static inline struct rte_mbuf *rte_mbuf_raw_alloc(struct rte_mempool *mp)
static __rte_always_inline void
rte_mbuf_raw_free(struct rte_mbuf *m)
{
- RTE_ASSERT(RTE_MBUF_DIRECT(m));
+ RTE_ASSERT(!RTE_MBUF_CLONED(m) &&
+ (!RTE_MBUF_HAS_EXTBUF(m) || RTE_MBUF_HAS_PINNED_EXTBUF(m)));
RTE_ASSERT(rte_mbuf_refcnt_read(m) == 1);
RTE_ASSERT(m->next == NULL);
RTE_ASSERT(m->nb_segs == 1);
@@ -1141,11 +1177,26 @@ static inline void rte_pktmbuf_detach(struct rte_mbuf *m)
uint32_t mbuf_size, buf_len;
uint16_t priv_size;
- if (RTE_MBUF_HAS_EXTBUF(m))
+ if (RTE_MBUF_HAS_EXTBUF(m)) {
+ /*
+ * The mbuf has the external attached buffed,
+ * we should check the type of the memory pool where
+ * the mbuf was allocated from to detect the pinned
+ * external buffer.
+ */
+ struct rte_pktmbuf_pool_private *priv =
+ (struct rte_pktmbuf_pool_private *)
+ rte_mempool_get_priv(mp);
+
+ if (priv->flags & RTE_PKTMBUF_POOL_F_PINNED_EXT_BUF) {
+ RTE_ASSERT(m->shinfo == NULL);
+ m->ol_flags = EXT_ATTACHED_MBUF;
+ return;
+ }
__rte_pktmbuf_free_extbuf(m);
- else
+ } else {
__rte_pktmbuf_free_direct(m);
-
+ }
priv_size = rte_pktmbuf_priv_size(mp);
mbuf_size = (uint32_t)(sizeof(struct rte_mbuf) + priv_size);
buf_len = rte_pktmbuf_data_room_size(mp);