Hello David,
please, see my comments inline.
I didn't see the previous versions of the mempool (well, only very roughly) so
I am
probably missing some points... My point of view is as a user of the handler
API.
I need to understand the API to implement a custom handler for my purposes.
On Thu, 19 May 2016 14:44:59 +0100
David Hunt <david.hunt at intel.com> wrote:
> Until now, the objects stored in mempool mempool were internally stored a
s/mempool mempool/mempool/
stored _in_ a ring?
> ring. This patch introduce the possibility to register external handlers
> replacing the ring.
>
> The default behavior remains unchanged, but calling the new function
> rte_mempool_set_handler() right after rte_mempool_create_empty() allows to
> change the handler that will be used when populating the mempool.
>
> v5 changes: rebasing on top of 35 patch set mempool work.
>
> Signed-off-by: David Hunt <david.hunt at intel.com>
> Signed-off-by: Olivier Matz <olivier.matz at 6wind.com>
>
> ---
> app/test/test_mempool_perf.c | 1 -
> lib/librte_mempool/Makefile | 2 +
> lib/librte_mempool/rte_mempool.c | 73 ++++------
> lib/librte_mempool/rte_mempool.h | 212
> +++++++++++++++++++++++++----
> lib/librte_mempool/rte_mempool_default.c | 147 ++++++++++++++++++++
> lib/librte_mempool/rte_mempool_handler.c | 139 +++++++++++++++++++
> lib/librte_mempool/rte_mempool_version.map | 4 +
> 7 files changed, 506 insertions(+), 72 deletions(-)
> create mode 100644 lib/librte_mempool/rte_mempool_default.c
> create mode 100644 lib/librte_mempool/rte_mempool_handler.c
>
> diff --git a/app/test/test_mempool_perf.c b/app/test/test_mempool_perf.c
> index cdc02a0..091c1df 100644
> --- a/app/test/test_mempool_perf.c
> +++ b/app/test/test_mempool_perf.c
> @@ -161,7 +161,6 @@ per_lcore_mempool_test(__attribute__((unused)) void *arg)
> n_get_bulk);
> if (unlikely(ret < 0)) {
> rte_mempool_dump(stdout, mp);
> - rte_ring_dump(stdout, mp->ring);
> /* in this case, objects are lost... */
> return -1;
> }
I think, this should be in a separate patch explaining the reason to remove it.
> diff --git a/lib/librte_mempool/Makefile b/lib/librte_mempool/Makefile
> index 43423e0..f19366e 100644
> --- a/lib/librte_mempool/Makefile
> +++ b/lib/librte_mempool/Makefile
> @@ -42,6 +42,8 @@ LIBABIVER := 2
>
> # all source are stored in SRCS-y
> SRCS-$(CONFIG_RTE_LIBRTE_MEMPOOL) += rte_mempool.c
> +SRCS-$(CONFIG_RTE_LIBRTE_MEMPOOL) += rte_mempool_handler.c
> +SRCS-$(CONFIG_RTE_LIBRTE_MEMPOOL) += rte_mempool_default.c
> # install includes
> SYMLINK-$(CONFIG_RTE_LIBRTE_MEMPOOL)-include := rte_mempool.h
>
> diff --git a/lib/librte_mempool/rte_mempool.c
> b/lib/librte_mempool/rte_mempool.c
> index 1ab6701..6ec2b3f 100644
> --- a/lib/librte_mempool/rte_mempool.c
> +++ b/lib/librte_mempool/rte_mempool.c
> @@ -148,7 +148,7 @@ mempool_add_elem(struct rte_mempool *mp, void *obj,
> phys_addr_t physaddr)
> #endif
>
> /* enqueue in ring */
> - rte_ring_sp_enqueue(mp->ring, obj);
> + rte_mempool_ext_put_bulk(mp, &obj, 1);
I suppose this is OK, however, replacing "enqueue" by "put" (semantically)
sounds to me
like a bug. Enqueue is put into a queue. Put is to drop a reference.
> }
>
> /* call obj_cb() for each mempool element */
> @@ -300,40 +300,6 @@ rte_mempool_xmem_usage(__rte_unused void *vaddr,
> uint32_t elt_num,
> return (size_t)paddr_idx << pg_shift;
> }
>
> -/* create the internal ring */
> -static int
> -rte_mempool_ring_create(struct rte_mempool *mp)
> -{
> - int rg_flags = 0, ret;
> - char rg_name[RTE_RING_NAMESIZE];
> - struct rte_ring *r;
> -
> - ret = snprintf(rg_name, sizeof(rg_name),
> - RTE_MEMPOOL_MZ_FORMAT, mp->name);
> - if (ret < 0 || ret >= (int)sizeof(rg_name))
> - return -ENAMETOOLONG;
> -
> - /* ring flags */
> - if (mp->flags & MEMPOOL_F_SP_PUT)
> - rg_flags |= RING_F_SP_ENQ;
> - if (mp->flags & MEMPOOL_F_SC_GET)
> - rg_flags |= RING_F_SC_DEQ;
> -
> - /* Allocate the ring that will be used to store objects.
> - * Ring functions will return appropriate errors if we are
> - * running as a secondary process etc., so no checks made
> - * in this function for that condition.
> - */
> - r = rte_ring_create(rg_name, rte_align32pow2(mp->size + 1),
> - mp->socket_id, rg_flags);
> - if (r == NULL)
> - return -rte_errno;
> -
> - mp->ring = r;
> - mp->flags |= MEMPOOL_F_RING_CREATED;
> - return 0;
> -}
This is a big change. I suggest (if possible) to make a separate patch with
something like "replace rte_mempool_ring_create by ...". Where is this code
placed now?
> -
> /* free a memchunk allocated with rte_memzone_reserve() */
> static void
> rte_mempool_memchunk_mz_free(__rte_unused struct rte_mempool_memhdr *memhdr,
> @@ -351,7 +317,7 @@ rte_mempool_free_memchunks(struct rte_mempool *mp)
> void *elt;
>
> while (!STAILQ_EMPTY(&mp->elt_list)) {
> - rte_ring_sc_dequeue(mp->ring, &elt);
> + rte_mempool_ext_get_bulk(mp, &elt, 1);
Similar as for put_bulk... Replacing "dequeue" by "get" (semantically) sounds
to me
like a bug. Dequeue is drop from a queue. Get is to obtain a reference.
> (void)elt;
> STAILQ_REMOVE_HEAD(&mp->elt_list, next);
> mp->populated_size--;
> @@ -380,15 +346,18 @@ rte_mempool_populate_phys(struct rte_mempool *mp, char
> *vaddr,
> unsigned i = 0;
> size_t off;
> struct rte_mempool_memhdr *memhdr;
> - int ret;
>
> /* create the internal ring if not already done */
> if ((mp->flags & MEMPOOL_F_RING_CREATED) == 0) {
> - ret = rte_mempool_ring_create(mp);
> - if (ret < 0)
> - return ret;
> + rte_errno = 0;
> + mp->pool = rte_mempool_ext_alloc(mp);
> + if (mp->pool == NULL) {
> + if (rte_errno == 0)
> + return -EINVAL;
> + else
> + return -rte_errno;
> + }
> }
> -
Is this a whitespace change?
> /* mempool is already populated */
> if (mp->populated_size >= mp->size)
> return -ENOSPC;
> @@ -700,7 +669,7 @@ rte_mempool_free(struct rte_mempool *mp)
> rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
>
> rte_mempool_free_memchunks(mp);
> - rte_ring_free(mp->ring);
> + rte_mempool_ext_free(mp);
> rte_memzone_free(mp->mz);
> }
>
> @@ -812,6 +781,20 @@ rte_mempool_create_empty(const char *name, unsigned n,
> unsigned elt_size,
> RTE_PTR_ADD(mp, MEMPOOL_HEADER_SIZE(mp, 0));
>
> te->data = mp;
> +
> + /*
> + * Since we have 4 combinations of the SP/SC/MP/MC examine the flags to
> + * set the correct index into the handler table.
> + */
> + if (flags & (MEMPOOL_F_SP_PUT | MEMPOOL_F_SC_GET))
> + rte_mempool_set_handler(mp, "ring_sp_sc");
> + else if (flags & MEMPOOL_F_SP_PUT)
> + rte_mempool_set_handler(mp, "ring_sp_mc");
> + else if (flags & MEMPOOL_F_SC_GET)
> + rte_mempool_set_handler(mp, "ring_mp_sc");
> + else
> + rte_mempool_set_handler(mp, "ring_mp_mc");
> +
Do I understand it well that this code preserves behaviour of the previous API?
Because otherwise it looks strange.
> rte_rwlock_write_lock(RTE_EAL_TAILQ_RWLOCK);
> TAILQ_INSERT_TAIL(mempool_list, te, next);
> rte_rwlock_write_unlock(RTE_EAL_TAILQ_RWLOCK);
> @@ -927,7 +910,7 @@ rte_mempool_count(const struct rte_mempool *mp)
> unsigned count;
> unsigned lcore_id;
>
> - count = rte_ring_count(mp->ring);
> + count = rte_mempool_ext_get_count(mp);
>
> if (mp->cache_size == 0)
> return count;
> @@ -1120,7 +1103,7 @@ rte_mempool_dump(FILE *f, struct rte_mempool *mp)
>
> fprintf(f, "mempool <%s>@%p\n", mp->name, mp);
> fprintf(f, " flags=%x\n", mp->flags);
> - fprintf(f, " ring=<%s>@%p\n", mp->ring->name, mp->ring);
> + fprintf(f, " pool=%p\n", mp->pool);
> fprintf(f, " phys_addr=0x%" PRIx64 "\n", mp->mz->phys_addr);
> fprintf(f, " nb_mem_chunks=%u\n", mp->nb_mem_chunks);
> fprintf(f, " size=%"PRIu32"\n", mp->size);
> @@ -1141,7 +1124,7 @@ rte_mempool_dump(FILE *f, struct rte_mempool *mp)
> }
>
> cache_count = rte_mempool_dump_cache(f, mp);
> - common_count = rte_ring_count(mp->ring);
> + common_count = rte_mempool_ext_get_count(mp);
> if ((cache_count + common_count) > mp->size)
> common_count = mp->size - cache_count;
> fprintf(f, " common_pool_count=%u\n", common_count);
> diff --git a/lib/librte_mempool/rte_mempool.h
> b/lib/librte_mempool/rte_mempool.h
> index 60339bd..ed2c110 100644
> --- a/lib/librte_mempool/rte_mempool.h
> +++ b/lib/librte_mempool/rte_mempool.h
> @@ -67,6 +67,7 @@
> #include <inttypes.h>
> #include <sys/queue.h>
>
> +#include <rte_spinlock.h>
> #include <rte_log.h>
> #include <rte_debug.h>
> #include <rte_lcore.h>
> @@ -203,7 +204,15 @@ struct rte_mempool_memhdr {
> */
> struct rte_mempool {
> char name[RTE_MEMPOOL_NAMESIZE]; /**< Name of mempool. */
> - struct rte_ring *ring; /**< Ring to store objects. */
> + void *pool; /**< Ring or ext-pool to store
> objects. */
> + /**
> + * Index into the array of structs containing callback fn pointers.
> + * We're using an index here rather than pointers to the callbacks
> + * to facilitate any secondary processes that may want to use
> + * this mempool. Any function pointers stored in the mempool
> + * directly would not be valid for secondary processes.
> + */
I think, this comment should go to the rte_mempool_handler_table definition
leaving a here a short note about it.
> + int32_t handler_idx;
> const struct rte_memzone *mz; /**< Memzone where pool is allocated */
> int flags; /**< Flags of the mempool. */
> int socket_id; /**< Socket id passed at mempool
> creation. */
> @@ -325,6 +334,175 @@ void rte_mempool_check_cookies(const struct rte_mempool
> *mp,
> #define __mempool_check_cookies(mp, obj_table_const, n, free) do {} while(0)
> #endif /* RTE_LIBRTE_MEMPOOL_DEBUG */
>
> +#define RTE_MEMPOOL_HANDLER_NAMESIZE 32 /**< Max length of handler name. */
> +
> +/** Allocate the external pool. */
What is the purpose of this callback?
What exactly does it allocate?
Some rte_mempool internals?
Or the memory?
What does it return?
> +typedef void *(*rte_mempool_alloc_t)(struct rte_mempool *mp);
> +
> +/** Free the external pool. */
Why this *_free callback does not accept the rte_mempool param?
> +typedef void (*rte_mempool_free_t)(void *p);
> +
> +/** Put an object in the external pool. */
What is the *p pointer?
What is the obj_table?
Why is it void *?
Why is it const?
> +typedef int (*rte_mempool_put_t)(void *p, void * const *obj_table, unsigned
> n);
Probably, "unsigned int n" is better.
> +
> +/** Get an object from the external pool. */
> +typedef int (*rte_mempool_get_t)(void *p, void **obj_table, unsigned n);
Probably, "unsigned int n" is better.
> +
> +/** Return the number of available objects in the external pool. */
What is the purpose of the *_get_count callback? I guess it can introduce
race conditions...
> +typedef unsigned (*rte_mempool_get_count)(void *p);
unsigned int
> +
> +/** Structure defining a mempool handler. */
Later in the text, I suggested to rename rte_mempool_handler to rte_mempool_ops.
I believe that it explains the purpose of this struct better. It would improve
consistency in function names (the *_ext_* mark is very strange and
inconsistent).
> +struct rte_mempool_handler {
> + char name[RTE_MEMPOOL_HANDLER_NAMESIZE]; /**< Name of mempool handler */
> + rte_mempool_alloc_t alloc; /**< Allocate the external pool. */
> + rte_mempool_free_t free; /**< Free the external pool. */
> + rte_mempool_put_t put; /**< Put an object. */
> + rte_mempool_get_t get; /**< Get an object. */
> + rte_mempool_get_count get_count; /**< Get the number of available objs.
> */
> +} __rte_cache_aligned;
> +
> +#define RTE_MEMPOOL_MAX_HANDLER_IDX 16 /**< Max number of registered
> handlers */
> +
> +/** Structure storing the table of registered handlers. */
> +struct rte_mempool_handler_table {
> + rte_spinlock_t sl; /**< Spinlock for add/delete. */
> + uint32_t num_handlers; /**< Number of handlers in the table. */
> + /** Storage for all possible handlers. */
> + struct rte_mempool_handler handler[RTE_MEMPOOL_MAX_HANDLER_IDX];
> +};
The handlers are implemented as an array due to multi-process access.
Is it correct? I'd expect a note about it here.
> +
> +/** Array of registered handlers */
> +extern struct rte_mempool_handler_table rte_mempool_handler_table;
> +
> +/**
> + * @internal Get the mempool handler from its index.
> + *
> + * @param handler_idx
> + * The index of the handler in the handler table. It must be a valid
> + * index: (0 <= idx < num_handlers).
> + * @return
> + * The pointer to the handler in the table.
> + */
> +static struct rte_mempool_handler *
> +rte_mempool_handler_get(int handler_idx)
> +{
> + return &rte_mempool_handler_table.handler[handler_idx];
Is it always safe? Can we belive the handler_idx is inside the boundaries?
At least some RTE_VERIFY would be nice here...
> +}
> +
> +/**
> + * @internal wrapper for external mempool manager alloc callback.
> + *
> + * @param mp
> + * Pointer to the memory pool.
> + * @return
> + * The opaque pointer to the external pool.
> + */
> +void *
> +rte_mempool_ext_alloc(struct rte_mempool *mp);
> +
> +/**
> + * @internal wrapper for external mempool manager get callback.
> + *
> + * @param mp
> + * Pointer to the memory pool.
> + * @param obj_table
> + * Pointer to a table of void * pointers (objects).
> + * @param n
> + * Number of objects to get.
> + * @return
> + * - 0: Success; got n objects.
> + * - <0: Error; code of handler get function.
Should this doc be more specific about the possible failures?
> + */
> +static inline int
> +rte_mempool_ext_get_bulk(struct rte_mempool *mp, void **obj_table, unsigned
> n)
> +{
> + struct rte_mempool_handler *handler;
> +
> + handler = rte_mempool_handler_get(mp->handler_idx);
> + return handler->get(mp->pool, obj_table, n);
> +}
> +
> +/**
> + * @internal wrapper for external mempool manager put callback.
> + *
> + * @param mp
> + * Pointer to the memory pool.
> + * @param obj_table
> + * Pointer to a table of void * pointers (objects).
> + * @param n
> + * Number of objects to put.
> + * @return
> + * - 0: Success; n objects supplied.
> + * - <0: Error; code of handler put function.
Should this doc be more specific about the possible failures?
> + */
> +static inline int
> +rte_mempool_ext_put_bulk(struct rte_mempool *mp, void * const *obj_table,
> + unsigned n)
> +{
> + struct rte_mempool_handler *handler;
> +
> + handler = rte_mempool_handler_get(mp->handler_idx);
> + return handler->put(mp->pool, obj_table, n);
> +}
> +
> +/**
> + * @internal wrapper for external mempool manager get_count callback.
> + *
> + * @param mp
> + * Pointer to the memory pool.
> + * @return
> + * The number of available objects in the external pool.
> + */
> +unsigned
unsigned int
> +rte_mempool_ext_get_count(const struct rte_mempool *mp);
> +
> +/**
> + * @internal wrapper for external mempool manager free callback.
> + *
> + * @param mp
> + * Pointer to the memory pool.
> + */
> +void
> +rte_mempool_ext_free(struct rte_mempool *mp);
> +
> +/**
> + * Set the handler of a mempool
> + *
> + * This can only be done on a mempool that is not populated, i.e. just after
> + * a call to rte_mempool_create_empty().
> + *
> + * @param mp
> + * Pointer to the memory pool.
> + * @param name
> + * Name of the handler.
> + * @return
> + * - 0: Sucess; the new handler is configured.
> + * - <0: Error (errno)
Should this doc be more specific about the possible failures?
The body of rte_mempool_set_handler does not set errno at all.
It returns e.g. -EEXIST.
> + */
> +int
> +rte_mempool_set_handler(struct rte_mempool *mp, const char *name);
> +
> +/**
> + * Register an external pool handler.
> + *
> + * @param h
> + * Pointer to the external pool handler
> + * @return
> + * - >=0: Sucess; return the index of the handler in the table.
> + * - <0: Error (errno)
Should this doc be more specific about the possible failures?
> + */
> +int rte_mempool_handler_register(struct rte_mempool_handler *h);
> +
> +/**
> + * Macro to statically register an external pool handler.
> + */
> +#define MEMPOOL_REGISTER_HANDLER(h) \
> + void mp_hdlr_init_##h(void); \
> + void __attribute__((constructor, used)) mp_hdlr_init_##h(void) \
> + { \
> + rte_mempool_handler_register(&h); \
> + }
> +
There might be a little catch. If there is no more room for handlers, calling
the
rte_mempool_handler_register would fail silently as the error reporting does not
work when calling a constructor (or at least, this is my experience).
Not a big deal but...
> /**
> * An object callback function for mempool.
> *
> @@ -736,7 +914,7 @@ void rte_mempool_dump(FILE *f, struct rte_mempool *mp);
> */
> static inline void __attribute__((always_inline))
> __mempool_put_bulk(struct rte_mempool *mp, void * const *obj_table,
> - unsigned n, int is_mp)
> + unsigned n, __rte_unused int is_mp)
> {
> struct rte_mempool_cache *cache;
> uint32_t index;
> @@ -774,7 +952,7 @@ __mempool_put_bulk(struct rte_mempool *mp, void * const
> *obj_table,
> cache->len += n;
>
> if (cache->len >= flushthresh) {
> - rte_ring_mp_enqueue_bulk(mp->ring, &cache->objs[cache_size],
> + rte_mempool_ext_put_bulk(mp, &cache->objs[cache_size],
> cache->len - cache_size);
> cache->len = cache_size;
> }
> @@ -782,26 +960,10 @@ __mempool_put_bulk(struct rte_mempool *mp, void * const
> *obj_table,
> return;
>
> ring_enqueue:
> -
> /* push remaining objects in ring */
> -#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
> - if (is_mp) {
> - if (rte_ring_mp_enqueue_bulk(mp->ring, obj_table, n) < 0)
> - rte_panic("cannot put objects in mempool\n");
> - }
> - else {
> - if (rte_ring_sp_enqueue_bulk(mp->ring, obj_table, n) < 0)
> - rte_panic("cannot put objects in mempool\n");
> - }
> -#else
> - if (is_mp)
> - rte_ring_mp_enqueue_bulk(mp->ring, obj_table, n);
> - else
> - rte_ring_sp_enqueue_bulk(mp->ring, obj_table, n);
> -#endif
> + rte_mempool_ext_put_bulk(mp, obj_table, n);
This is a big change. Does it remove the RTE_LIBRTE_MEMPOOL_DEBUG config option
entirely? If so, I suggest to first do this in a separated patch and then
replace the original *_enqueue_bulk by your *_ext_put_bulk (or better
*_ops_put_bulk
as I explain below).
> }
>
> -
> /**
> * Put several objects back in the mempool (multi-producers safe).
> *
> @@ -922,7 +1084,7 @@ rte_mempool_put(struct rte_mempool *mp, void *obj)
> */
> static inline int __attribute__((always_inline))
> __mempool_get_bulk(struct rte_mempool *mp, void **obj_table,
> - unsigned n, int is_mc)
> + unsigned n, __rte_unused int is_mc)
> {
> int ret;
> struct rte_mempool_cache *cache;
> @@ -945,7 +1107,8 @@ __mempool_get_bulk(struct rte_mempool *mp, void
> **obj_table,
> uint32_t req = n + (cache_size - cache->len);
>
> /* How many do we require i.e. number to fill the cache + the
> request */
> - ret = rte_ring_mc_dequeue_bulk(mp->ring,
> &cache->objs[cache->len], req);
> + ret = rte_mempool_ext_get_bulk(mp,
> + &cache->objs[cache->len], req);
> if (unlikely(ret < 0)) {
> /*
> * In the offchance that we are buffer constrained,
> @@ -972,10 +1135,7 @@ __mempool_get_bulk(struct rte_mempool *mp, void
> **obj_table,
> ring_dequeue:
>
> /* get remaining objects from ring */
> - if (is_mc)
> - ret = rte_ring_mc_dequeue_bulk(mp->ring, obj_table, n);
> - else
> - ret = rte_ring_sc_dequeue_bulk(mp->ring, obj_table, n);
> + ret = rte_mempool_ext_get_bulk(mp, obj_table, n);
>
> if (ret < 0)
> __MEMPOOL_STAT_ADD(mp, get_fail, n);
> diff --git a/lib/librte_mempool/rte_mempool_default.c
> b/lib/librte_mempool/rte_mempool_default.c
> new file mode 100644
> index 0000000..a6ac65a
> --- /dev/null
> +++ b/lib/librte_mempool/rte_mempool_default.c
> @@ -0,0 +1,147 @@
> +/*-
> + * BSD LICENSE
> + *
> + * Copyright(c) 2010-2016 Intel Corporation. All rights reserved.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + *
> + * * Redistributions of source code must retain the above copyright
> + * notice, this list of conditions and the following disclaimer.
> + * * Redistributions in binary form must reproduce the above copyright
> + * notice, this list of conditions and the following disclaimer in
> + * the documentation and/or other materials provided with the
> + * distribution.
> + * * Neither the name of Intel Corporation nor the names of its
> + * contributors may be used to endorse or promote products derived
> + * from this software without specific prior written permission.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
> + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
> + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
> + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
> + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
> + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
> + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +#include <stdio.h>
> +#include <string.h>
> +
> +#include <rte_errno.h>
> +#include <rte_ring.h>
> +#include <rte_mempool.h>
> +
> +static int
> +common_ring_mp_put(void *p, void * const *obj_table, unsigned n)
> +{
> + return rte_ring_mp_enqueue_bulk((struct rte_ring *)p, obj_table, n);
> +}
> +
> +static int
> +common_ring_sp_put(void *p, void * const *obj_table, unsigned n)
> +{
> + return rte_ring_sp_enqueue_bulk((struct rte_ring *)p, obj_table, n);
> +}
> +
> +static int
> +common_ring_mc_get(void *p, void **obj_table, unsigned n)
> +{
> + return rte_ring_mc_dequeue_bulk((struct rte_ring *)p, obj_table, n);
> +}
> +
> +static int
> +common_ring_sc_get(void *p, void **obj_table, unsigned n)
> +{
> + return rte_ring_sc_dequeue_bulk((struct rte_ring *)p, obj_table, n);
> +}
> +
> +static unsigned
> +common_ring_get_count(void *p)
> +{
> + return rte_ring_count((struct rte_ring *)p);
> +}
> +
> +
> +static void *
> +common_ring_alloc(struct rte_mempool *mp)
> +{
> + int rg_flags = 0, ret;
> + char rg_name[RTE_RING_NAMESIZE];
> + struct rte_ring *r;
> +
> + ret = snprintf(rg_name, sizeof(rg_name),
> + RTE_MEMPOOL_MZ_FORMAT, mp->name);
> + if (ret < 0 || ret >= (int)sizeof(rg_name)) {
> + rte_errno = ENAMETOOLONG;
> + return NULL;
> + }
> +
> + /* ring flags */
> + if (mp->flags & MEMPOOL_F_SP_PUT)
> + rg_flags |= RING_F_SP_ENQ;
> + if (mp->flags & MEMPOOL_F_SC_GET)
> + rg_flags |= RING_F_SC_DEQ;
> +
> + /* Allocate the ring that will be used to store objects.
> + * Ring functions will return appropriate errors if we are
> + * running as a secondary process etc., so no checks made
> + * in this function for that condition. */
> + r = rte_ring_create(rg_name, rte_align32pow2(mp->size + 1),
> + mp->socket_id, rg_flags);
> +
> + return r;
> +}
> +
> +static void
> +common_ring_free(void *p)
> +{
> + rte_ring_free((struct rte_ring *)p);
> +}
> +
> +static struct rte_mempool_handler handler_mp_mc = {
> + .name = "ring_mp_mc",
> + .alloc = common_ring_alloc,
> + .free = common_ring_free,
> + .put = common_ring_mp_put,
> + .get = common_ring_mc_get,
> + .get_count = common_ring_get_count,
> +};
> +
> +static struct rte_mempool_handler handler_sp_sc = {
> + .name = "ring_sp_sc",
> + .alloc = common_ring_alloc,
> + .free = common_ring_free,
> + .put = common_ring_sp_put,
> + .get = common_ring_sc_get,
> + .get_count = common_ring_get_count,
> +};
> +
> +static struct rte_mempool_handler handler_mp_sc = {
> + .name = "ring_mp_sc",
> + .alloc = common_ring_alloc,
> + .free = common_ring_free,
> + .put = common_ring_mp_put,
> + .get = common_ring_sc_get,
> + .get_count = common_ring_get_count,
> +};
> +
> +static struct rte_mempool_handler handler_sp_mc = {
> + .name = "ring_sp_mc",
> + .alloc = common_ring_alloc,
> + .free = common_ring_free,
> + .put = common_ring_sp_put,
> + .get = common_ring_mc_get,
> + .get_count = common_ring_get_count,
> +};
> +
Introducing those handlers can go as a separate patch. IMHO, that would simplify
the review process a lot. First introduce the mechanism, then add something
inside.
I'd also note that those handlers are always available and what kind of memory
do they use...
> +MEMPOOL_REGISTER_HANDLER(handler_mp_mc);
> +MEMPOOL_REGISTER_HANDLER(handler_sp_sc);
> +MEMPOOL_REGISTER_HANDLER(handler_mp_sc);
> +MEMPOOL_REGISTER_HANDLER(handler_sp_mc);
> diff --git a/lib/librte_mempool/rte_mempool_handler.c
> b/lib/librte_mempool/rte_mempool_handler.c
> new file mode 100644
> index 0000000..78611f8
> --- /dev/null
> +++ b/lib/librte_mempool/rte_mempool_handler.c
> @@ -0,0 +1,139 @@
> +/*-
> + * BSD LICENSE
> + *
> + * Copyright(c) 2016 Intel Corporation. All rights reserved.
> + * Copyright(c) 2016 6WIND S.A.
> + * All rights reserved.
> + *
> + * Redistribution and use in source and binary forms, with or without
> + * modification, are permitted provided that the following conditions
> + * are met:
> + *
> + * * Redistributions of source code must retain the above copyright
> + * notice, this list of conditions and the following disclaimer.
> + * * Redistributions in binary form must reproduce the above copyright
> + * notice, this list of conditions and the following disclaimer in
> + * the documentation and/or other materials provided with the
> + * distribution.
> + * * Neither the name of Intel Corporation nor the names of its
> + * contributors may be used to endorse or promote products derived
> + * from this software without specific prior written permission.
> + *
> + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
> + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
> + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
> + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
> + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
> + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
> + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
> + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
> + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
> + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
> + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
> + */
> +
> +#include <stdio.h>
> +#include <string.h>
> +
> +#include <rte_mempool.h>
> +
> +/* indirect jump table to support external memory pools */
> +struct rte_mempool_handler_table rte_mempool_handler_table = {
> + .sl = RTE_SPINLOCK_INITIALIZER ,
> + .num_handlers = 0
> +};
> +
> +/* add a new handler in rte_mempool_handler_table, return its index */
It seems to me that there is no way how to put some opaque pointer into the
handler. In such case I would expect I can do something like:
struct my_handler {
struct rte_mempool_handler h;
...
} handler;
rte_mempool_handler_register(&handler.h);
But I cannot because you copy the contents of the handler. By the way, this
should be documented.
How can I pass an opaque pointer here? The only way I see is through the
rte_mempool.pool. In that case, what about renaming the rte_mempool_handler
to rte_mempool_ops? Because semantically, it is not a handler, it just holds
the operations.
This would improve some namings:
rte_mempool_ext_alloc -> rte_mempool_ops_alloc
rte_mempool_ext_free -> rte_mempool_ops_free
rte_mempool_ext_get_count -> rte_mempool_ops_get_count
rte_mempool_handler_register -> rte_mempool_ops_register
seems to be more readable to me. The *_ext_* mark does not say anything
valuable.
It just scares a bit :).
> +int
> +rte_mempool_handler_register(struct rte_mempool_handler *h)
> +{
> + struct rte_mempool_handler *handler;
> + int16_t handler_idx;
> +
> + rte_spinlock_lock(&rte_mempool_handler_table.sl);
> +
> + if (rte_mempool_handler_table.num_handlers >=
> RTE_MEMPOOL_MAX_HANDLER_IDX) {
> + rte_spinlock_unlock(&rte_mempool_handler_table.sl);
> + RTE_LOG(ERR, MEMPOOL,
> + "Maximum number of mempool handlers exceeded\n");
> + return -ENOSPC;
> + }
> +
> + if (h->put == NULL || h->get == NULL || h->get_count == NULL) {
> + rte_spinlock_unlock(&rte_mempool_handler_table.sl);
> + RTE_LOG(ERR, MEMPOOL,
> + "Missing callback while registering mempool handler\n");
> + return -EINVAL;
> + }
> +
> + handler_idx = rte_mempool_handler_table.num_handlers++;
> + handler = &rte_mempool_handler_table.handler[handler_idx];
> + snprintf(handler->name, sizeof(handler->name), "%s", h->name);
> + handler->alloc = h->alloc;
> + handler->put = h->put;
> + handler->get = h->get;
> + handler->get_count = h->get_count;
> +
> + rte_spinlock_unlock(&rte_mempool_handler_table.sl);
> +
> + return handler_idx;
> +}
> +
> +/* wrapper to allocate an external pool handler */
> +void *
> +rte_mempool_ext_alloc(struct rte_mempool *mp)
> +{
> + struct rte_mempool_handler *handler;
> +
> + handler = rte_mempool_handler_get(mp->handler_idx);
> + if (handler->alloc == NULL)
> + return NULL;
> + return handler->alloc(mp);
> +}
> +
> +/* wrapper to free an external pool handler */
> +void
> +rte_mempool_ext_free(struct rte_mempool *mp)
> +{
> + struct rte_mempool_handler *handler;
> +
> + handler = rte_mempool_handler_get(mp->handler_idx);
> + if (handler->free == NULL)
> + return;
> + return handler->free(mp);
> +}
> +
> +/* wrapper to get available objects in an external pool handler */
> +unsigned
> +rte_mempool_ext_get_count(const struct rte_mempool *mp)
> +{
> + struct rte_mempool_handler *handler;
> +
> + handler = rte_mempool_handler_get(mp->handler_idx);
> + return handler->get_count(mp->pool);
> +}
> +
> +/* set the handler of a mempool */
The doc comment should say "this sets a handler previously registered by
the rte_mempool_handler_register function ...". I was confused and didn't
understand how the handlers are inserted into the table.
> +int
> +rte_mempool_set_handler(struct rte_mempool *mp, const char *name)
> +{
> + struct rte_mempool_handler *handler = NULL;
> + unsigned i;
> +
> + /* too late, the mempool is already populated */
> + if (mp->flags & MEMPOOL_F_RING_CREATED)
> + return -EEXIST;
> +
> + for (i = 0; i < rte_mempool_handler_table.num_handlers; i++) {
> + if (!strcmp(name, rte_mempool_handler_table.handler[i].name)) {
> + handler = &rte_mempool_handler_table.handler[i];
> + break;
> + }
> + }
> +
> + if (handler == NULL)
> + return -EINVAL;
> +
> + mp->handler_idx = i;
> + return 0;
> +}
> diff --git a/lib/librte_mempool/rte_mempool_version.map
> b/lib/librte_mempool/rte_mempool_version.map
> index f63461b..a0e9aed 100644
> --- a/lib/librte_mempool/rte_mempool_version.map
> +++ b/lib/librte_mempool/rte_mempool_version.map
> @@ -19,6 +19,8 @@ DPDK_2.0 {
> DPDK_16.7 {
> global:
>
> + rte_mempool_handler_table;
> +
> rte_mempool_check_cookies;
> rte_mempool_obj_iter;
> rte_mempool_mem_iter;
> @@ -29,6 +31,8 @@ DPDK_16.7 {
> rte_mempool_populate_default;
> rte_mempool_populate_anon;
> rte_mempool_free;
> + rte_mempool_set_handler;
> + rte_mempool_handler_register;
>
> local: *;
> } DPDK_2.0;
Regards
Jan
