> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Bruce Richardson > Sent: Monday, October 06, 2014 3:54 PM > To: Wiles, Roger Keith (Wind River) > Cc: dev at dpdk.org > Subject: Re: [dpdk-dev] [PATCH 2/2] Adding the routines > rte_pktmbuf_alloc_bulk() and rte_pktmbuf_free_bulk() > > On Mon, Oct 06, 2014 at 03:50:38PM +0100, Wiles, Roger Keith wrote: > > Hi Bruce, > > > > Do I need to reject the for the new routines or just make sure the vector > > driver does not get updated to use those routines? > > > > The new routines are probably useful in the general case. I see no issue > with having them in the code, so long as the vector driver is not modified > to use them.
I 'd say the same thing for non-vector RX/TX PMD code-paths too. BTW, are the new functions comments valid? + * @return + * - 0 if the number of mbufs allocated was ok + * - <0 is an ERROR. + */ +static inline int __rte_mbuf_raw_alloc_bulk( Though, as I can see __rte_mbuf_raw_alloc_bulk() returns either: - number of allocated mbuf (cnt) - negative error code And: + * @return + * - The number of valid mbufs pointers in the m_list array. + * - Zero if the request cnt could not be allocated. + */ +static inline int __attribute__((always_inline)) +rte_pktmbuf_alloc_bulk(struct rte_mempool *mp, struct rte_mbuf *m_list[], int16_t cnt) +{ + return __rte_mbuf_raw_alloc_bulk(mp, m_list, cnt); +} Shouldn't be "less than zero if the request cnt could not be allocated."? BTW, is there any point to have __rte_mbuf_raw_alloc_bulk() at all? After all, as you are calling rte_pktmbuf_reset() inside it, it doesn't look __raw__ any more. Might be just put its content into rte_pktmbuf_alloc_bulk() and get rid of it. Also wonder, what is the advantage of having multiple counters inside the same loop? i.e: + for(i = 0; i < cnt; i++) { + m = *m_list++; Why not just: for(i = 0; i < cnt; i++) { m = &m_list[i]; Same for free: + while(npkts--) + rte_pktmbuf_free(*m_list++); While not just: for (i = 0; i < npkts; i++) rte_pktmbuf_free(&m_list[i]); Konstantin > > /Bruce > > > Thanks > > ++Keith > > > > On Oct 6, 2014, at 3:56 AM, Richardson, Bruce <bruce.richardson at > > intel.com> wrote: > > > > > > > > > > >> -----Original Message----- > > >> From: dev [mailto:dev-bounces at dpdk.org] On Behalf Of Keith Wiles > > >> Sent: Sunday, October 05, 2014 12:10 AM > > >> To: dev at dpdk.org > > >> Subject: [dpdk-dev] [PATCH 2/2] Adding the routines > > >> rte_pktmbuf_alloc_bulk() > > >> and rte_pktmbuf_free_bulk() > > >> > > >> Minor helper routines to mirror the mempool routines and remove the code > > >> from applications. The ixgbe_rxtx_vec.c routine could be changed to use > > >> the ret_pktmbuf_alloc_bulk() routine inplace of rte_mempool_get_bulk(). > > >> > > > > > > I believe such a change would cause a performance regression, as the > > > extra init code in the alloc_bulk() function would take > additional cycles and is not needed. The vector routines use the mempool > function directly, so that there is no overhead of mbuf > initialization, as the vector routines use their additional "knowledge" of > what the mbufs will be used for to init them in a faster manner > than can be done inside the mbuf library. > > > > > > /Bruce > > > > > >> Signed-off-by: Keith Wiles <keith.wiles at windriver.com> > > >> --- > > >> lib/librte_mbuf/rte_mbuf.h | 77 > > >> ++++++++++++++++++++++++++++++++++++++++++++++ > > >> 1 file changed, 77 insertions(+) > > >> > > >> diff --git a/lib/librte_mbuf/rte_mbuf.h b/lib/librte_mbuf/rte_mbuf.h > > >> index 1c6e115..f298621 100644 > > >> --- a/lib/librte_mbuf/rte_mbuf.h > > >> +++ b/lib/librte_mbuf/rte_mbuf.h > > >> @@ -546,6 +546,41 @@ static inline void rte_pktmbuf_reset(struct rte_mbuf > > >> *m) > > >> } > > >> > > >> /** > > >> + * @internal Allocate a list of mbufs from mempool *mp*. > > >> + * The use of that function is reserved for RTE internal needs. > > >> + * Please use rte_pktmbuf_alloc_bulk(). > > >> + * > > >> + * @param mp > > >> + * The mempool from which mbuf is allocated. > > >> + * @param m_list > > >> + * The array to place the allocated rte_mbufs pointers. > > >> + * @param cnt > > >> + * The number of mbufs to allocate > > >> + * @return > > >> + * - 0 if the number of mbufs allocated was ok > > >> + * - <0 is an ERROR. > > >> + */ > > >> +static inline int __rte_mbuf_raw_alloc_bulk(struct rte_mempool *mp, > > >> struct > > >> rte_mbuf *m_list[], int cnt) > > >> +{ > > >> + struct rte_mbuf *m; > > >> + int ret; > > >> + > > >> + ret = rte_mempool_get_bulk(mp, (void **)m_list, cnt); > > >> + if ( ret == 0 ) { > > >> + int i; > > >> + for(i = 0; i < cnt; i++) { > > >> + m = *m_list++; > > >> +#ifdef RTE_MBUF_REFCNT > > >> + rte_mbuf_refcnt_set(m, 1); > > >> +#endif /* RTE_MBUF_REFCNT */ > > >> + rte_pktmbuf_reset(m); > > >> + } > > >> + ret = cnt; > > >> + } > > >> + return ret; > > >> +} > > >> + > > >> +/** > > >> * Allocate a new mbuf from a mempool. > > >> * > > >> * This new mbuf contains one segment, which has a length of 0. The > > >> pointer > > >> @@ -671,6 +706,32 @@ __rte_pktmbuf_prefree_seg(struct rte_mbuf *m) > > >> } > > >> > > >> /** > > >> + * Allocate a list of mbufs from a mempool into a mbufs array. > > >> + * > > >> + * This mbuf list contains one segment per mbuf, which has a length of > > >> 0. The > > >> pointer > > >> + * to data is initialized to have some bytes of headroom in the buffer > > >> + * (if buffer size allows). > > >> + * > > >> + * The routine is just a simple wrapper routine to reduce code in the > > >> application > > >> and > > >> + * provide a cleaner API for multiple mbuf requests. > > >> + * > > >> + * @param mp > > >> + * The mempool from which the mbuf is allocated. > > >> + * @param m_list > > >> + * An array of mbuf pointers, cnt must be less then or equal to the > > >> size of the > > >> list. > > >> + * @param cnt > > >> + * Number of slots in the m_list array to fill. > > >> + * @return > > >> + * - The number of valid mbufs pointers in the m_list array. > > >> + * - Zero if the request cnt could not be allocated. > > >> + */ > > >> +static inline int __attribute__((always_inline)) > > >> +rte_pktmbuf_alloc_bulk(struct rte_mempool *mp, struct rte_mbuf > > >> *m_list[], > > >> int16_t cnt) > > >> +{ > > >> + return __rte_mbuf_raw_alloc_bulk(mp, m_list, cnt); > > >> +} > > >> + > > >> +/** > > >> * Free a segment of a packet mbuf into its original mempool. > > >> * > > >> * Free an mbuf, without parsing other segments in case of chained > > >> @@ -708,6 +769,22 @@ static inline void rte_pktmbuf_free(struct rte_mbuf > > >> *m) > > >> } > > >> } > > >> > > >> +/** > > >> + * Free a list of packet mbufs back into its original mempool. > > >> + * > > >> + * Free a list of mbufs by calling rte_pktmbuf_free() in a loop as a > > >> wrapper > > >> function. > > >> + * > > >> + * @param m_list > > >> + * An array of rte_mbuf pointers to be freed. > > >> + * @param npkts > > >> + * Number of packets to free in list. > > >> + */ > > >> +static inline void rte_pktmbuf_free_bulk(struct rte_mbuf *m_list[], > > >> int16_t > > >> npkts) > > >> +{ > > >> + while(npkts--) > > >> + rte_pktmbuf_free(*m_list++); > > >> +} > > >> + > > >> #ifdef RTE_MBUF_REFCNT > > >> > > >> /** > > >> -- > > >> 2.1.0 > > > > > > > Keith Wiles, Principal Technologist with CTO office, Wind River mobile > > 972-213-5533 > >