[dpdk-dev] [PATCH 0/3] mempool: clean-up

[dpdk-dev] [PATCH 0/3] mempool: clean-up

[Olivier Matz]

These 3 patches try to make mempool code easier to read, they
have no functional impact.

Olivier Matz (3):
  mempool: introduce objhdr structure for object headers
  mempool: introduce objtlr structure for object trailers
  mempool: fix typos, indentation, and doxygen style

 lib/librte_mempool/rte_dom0_mempool.c |  36 +++----
 lib/librte_mempool/rte_mempool.c      |  22 ++--
 lib/librte_mempool/rte_mempool.h      | 188 ++++++++++++++++++----------------
 3 files changed, 128 insertions(+), 118 deletions(-)

-- 
2.1.4

[dpdk-dev] [PATCH 1/3] mempool: introduce objhdr structure for object headers

[Olivier Matz]

Each object stored in mempools are prefixed by a header, allowing for
instance to retrieve the mempool pointer from the object. When debug is
enabled, a cookie is also added in this header that helps to detect
corruptions and double-frees.

Introduce a structure that materializes the content of this header,
and will simplify future patches adding things in this header.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
 lib/librte_mempool/rte_mempool.c |  8 ++---
 lib/librte_mempool/rte_mempool.h | 68 ++++++++++++++++------------------------
 2 files changed, 31 insertions(+), 45 deletions(-)

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index 190cfd9..b2d8700 100644
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -130,16 +130,16 @@ static void
 mempool_add_elem(struct rte_mempool *mp, void *obj, uint32_t obj_idx,
 	rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg)
 {
-	struct rte_mempool **mpp;
+	struct rte_mempool_objhdr *hdr;
 
 	obj = (char *)obj + mp->header_size;
 
 	/* set mempool ptr in header */
-	mpp = __mempool_from_obj(obj);
-	*mpp = mp;
+	hdr = (struct rte_mempool_objhdr *)((char *)obj - sizeof(*hdr));
+	hdr->mp = mp;
 
 #ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-	__mempool_write_header_cookie(obj, 1);
+	hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE2;
 	__mempool_write_trailer_cookie(obj);
 #endif
 	/* call the initializer */
diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index a4a9610..5058940 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -140,6 +140,21 @@ struct rte_mempool_objsz {
 #define	MEMPOOL_PG_NUM_DEFAULT	1
 
 /**
+ * Mempool object header structure
+ *
+ * Each object stored in mempools are prefixed by this header structure,
+ * it allows to retrieve the mempool pointer from the object. When debug
+ * is enabled, a cookie is also added in this structure preventing
+ * corruptions and double-frees.
+ */
+struct rte_mempool_objhdr {
+	struct rte_mempool *mp;          /**< The mempool owning the object. */
+#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
+	uint64_t cookie;                 /**< Debug cookie. */
+#endif
+};
+
+/**
  * The RTE mempool structure.
  */
 struct rte_mempool {
@@ -227,24 +242,11 @@ struct rte_mempool {
 	((mp)->pg_num == MEMPOOL_PG_NUM_DEFAULT && \
 	(mp)->phys_addr == (mp)->elt_pa[0])
 
-/**
- * @internal Get a pointer to a mempool pointer in the object header.
- * @param obj
- *   Pointer to object.
- * @return
- *   The pointer to the mempool from which the object was allocated.
- */
-static inline struct rte_mempool **__mempool_from_obj(void *obj)
+/* return the header of a mempool object (internal) */
+static inline struct rte_mempool_objhdr *__mempool_get_header(void *obj)
 {
-	struct rte_mempool **mpp;
-	unsigned off;
-
-	off = sizeof(struct rte_mempool *);
-#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-	off += sizeof(uint64_t);
-#endif
-	mpp = (struct rte_mempool **)((char *)obj - off);
-	return mpp;
+	return (struct rte_mempool_objhdr *)((char *)obj -
+		sizeof(struct rte_mempool_objhdr));
 }
 
 /**
@@ -256,36 +258,18 @@ static inline struct rte_mempool **__mempool_from_obj(void *obj)
  * @return
  *   A pointer to the mempool structure.
  */
-static inline const struct rte_mempool *rte_mempool_from_obj(void *obj)
+static inline struct rte_mempool *rte_mempool_from_obj(void *obj)
 {
-	struct rte_mempool * const *mpp;
-	mpp = __mempool_from_obj(obj);
-	return *mpp;
+	struct rte_mempool_objhdr *hdr = __mempool_get_header(obj);
+	return hdr->mp;
 }
 
 #ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-/* get header cookie value */
-static inline uint64_t __mempool_read_header_cookie(const void *obj)
-{
-	return *(const uint64_t *)((const char *)obj - sizeof(uint64_t));
-}
-
 /* get trailer cookie value */
 static inline uint64_t __mempool_read_trailer_cookie(void *obj)
 {
 	struct rte_mempool **mpp = __mempool_from_obj(obj);
 	return *(uint64_t *)((char *)obj + (*mpp)->elt_size);
-}
-
-/* write header cookie value */
-static inline void __mempool_write_header_cookie(void *obj, int free)
-{
-	uint64_t *cookie_p;
-	cookie_p = (uint64_t *)((char *)obj - sizeof(uint64_t));
-	if (free == 0)
-		*cookie_p = RTE_MEMPOOL_HEADER_COOKIE1;
-	else
-		*cookie_p = RTE_MEMPOOL_HEADER_COOKIE2;
 
 }
 
@@ -321,6 +305,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					   void * const *obj_table_const,
 					   unsigned n, int free)
 {
+	struct rte_mempool_objhdr *hdr;
 	uint64_t cookie;
 	void *tmp;
 	void *obj;
@@ -338,7 +323,8 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 			rte_panic("MEMPOOL: object is owned by another "
 				  "mempool\n");
 
-		cookie = __mempool_read_header_cookie(obj);
+		hdr = __mempool_get_header(obj);
+		cookie = hdr->cookie;
 
 		if (free == 0) {
 			if (cookie != RTE_MEMPOOL_HEADER_COOKIE1) {
@@ -348,7 +334,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					obj, (const void *) mp, cookie);
 				rte_panic("MEMPOOL: bad header cookie (put)\n");
 			}
-			__mempool_write_header_cookie(obj, 1);
+			hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE2;
 		}
 		else if (free == 1) {
 			if (cookie != RTE_MEMPOOL_HEADER_COOKIE2) {
@@ -358,7 +344,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					obj, (const void *) mp, cookie);
 				rte_panic("MEMPOOL: bad header cookie (get)\n");
 			}
-			__mempool_write_header_cookie(obj, 0);
+			hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE1;
 		}
 		else if (free == 2) {
 			if (cookie != RTE_MEMPOOL_HEADER_COOKIE1 &&
-- 
2.1.4

[dpdk-dev] [PATCH 2/3] mempool: introduce objtlr structure for object trailers

[Olivier Matz]

Each object stored in mempools are suffixed by a trailer, storing
a cookie in debug mode which help to detect memory corruptions.

Like for headers, introduce a structure that materializes the content of
this trailer.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
 lib/librte_mempool/rte_mempool.c |  4 +++-
 lib/librte_mempool/rte_mempool.h | 42 +++++++++++++++++++++-------------------
 2 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index b2d8700..60369cf 100644
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -131,6 +131,7 @@ mempool_add_elem(struct rte_mempool *mp, void *obj, uint32_t obj_idx,
 	rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg)
 {
 	struct rte_mempool_objhdr *hdr;
+	struct rte_mempool_objtlr *tlr __rte_unused;
 
 	obj = (char *)obj + mp->header_size;
 
@@ -140,7 +141,8 @@ mempool_add_elem(struct rte_mempool *mp, void *obj, uint32_t obj_idx,
 
 #ifdef RTE_LIBRTE_MEMPOOL_DEBUG
 	hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE2;
-	__mempool_write_trailer_cookie(obj);
+	tlr = __mempool_get_trailer(obj);
+	tlr->cookie = RTE_MEMPOOL_TRAILER_COOKIE;
 #endif
 	/* call the initializer */
 	if (obj_init)
diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index 5058940..cdb8f67 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -155,6 +155,18 @@ struct rte_mempool_objhdr {
 };
 
 /**
+ * Mempool object trailer structure
+ *
+ * In debug mode, each object stored in mempools are suffixed by this
+ * trailer structure containing a cookie preventing memory corruptions.
+ */
+struct rte_mempool_objtlr {
+#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
+	uint64_t cookie;                 /**< Debug cookie. */
+#endif
+};
+
+/**
  * The RTE mempool structure.
  */
 struct rte_mempool {
@@ -249,6 +261,13 @@ static inline struct rte_mempool_objhdr *__mempool_get_header(void *obj)
 		sizeof(struct rte_mempool_objhdr));
 }
 
+/* return the trailer of a mempool object (internal) */
+static inline struct rte_mempool_objtlr *__mempool_get_trailer(void *obj)
+{
+	return (struct rte_mempool_objtlr *)((char *)obj -
+		sizeof(struct rte_mempool_objtlr));
+}
+
 /**
  * Return a pointer to the mempool owning this object.
  *
@@ -264,25 +283,6 @@ static inline struct rte_mempool *rte_mempool_from_obj(void *obj)
 	return hdr->mp;
 }
 
-#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-/* get trailer cookie value */
-static inline uint64_t __mempool_read_trailer_cookie(void *obj)
-{
-	struct rte_mempool **mpp = __mempool_from_obj(obj);
-	return *(uint64_t *)((char *)obj + (*mpp)->elt_size);
-
-}
-
-/* write trailer cookie value */
-static inline void __mempool_write_trailer_cookie(void *obj)
-{
-	uint64_t *cookie_p;
-	struct rte_mempool **mpp = __mempool_from_obj(obj);
-	cookie_p = (uint64_t *)((char *)obj + (*mpp)->elt_size);
-	*cookie_p = RTE_MEMPOOL_TRAILER_COOKIE;
-}
-#endif /* RTE_LIBRTE_MEMPOOL_DEBUG */
-
 /**
  * @internal Check and update cookies or panic.
  *
@@ -306,6 +306,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					   unsigned n, int free)
 {
 	struct rte_mempool_objhdr *hdr;
+	struct rte_mempool_objtlr *tlr;
 	uint64_t cookie;
 	void *tmp;
 	void *obj;
@@ -356,7 +357,8 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 				rte_panic("MEMPOOL: bad header cookie (audit)\n");
 			}
 		}
-		cookie = __mempool_read_trailer_cookie(obj);
+		tlr = __mempool_get_trailer(obj);
+		cookie = tlr->cookie;
 		if (cookie != RTE_MEMPOOL_TRAILER_COOKIE) {
 			rte_log_set_history(0);
 			RTE_LOG(CRIT, MEMPOOL,
-- 
2.1.4

[dpdk-dev] [PATCH 3/3] mempool: fix typos, indentation, and doxygen style

[Olivier Matz]

Do some cosmetic clean-up.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
 lib/librte_mempool/rte_dom0_mempool.c | 36 ++++++++--------
 lib/librte_mempool/rte_mempool.c      | 10 ++---
 lib/librte_mempool/rte_mempool.h      | 80 ++++++++++++++++++++++-------------
 3 files changed, 73 insertions(+), 53 deletions(-)

diff --git a/lib/librte_mempool/rte_dom0_mempool.c b/lib/librte_mempool/rte_dom0_mempool.c
index 8900171..a313b3f 100644
--- a/lib/librte_mempool/rte_dom0_mempool.c
+++ b/lib/librte_mempool/rte_dom0_mempool.c
@@ -61,30 +61,30 @@
 
 static void
 get_phys_map(void *va, phys_addr_t pa[], uint32_t pg_num,
-            uint32_t pg_sz, uint32_t memseg_id)
+	uint32_t pg_sz, uint32_t memseg_id)
 {
-    uint32_t i;
-    uint64_t virt_addr, mfn_id;
-    struct rte_mem_config *mcfg;
-    uint32_t page_size = getpagesize();
-
-    /* get pointer to global configuration */
-    mcfg = rte_eal_get_configuration()->mem_config;
-    virt_addr =(uintptr_t) mcfg->memseg[memseg_id].addr;
-
-    for (i = 0; i != pg_num; i++) {
-        mfn_id = ((uintptr_t)va + i * pg_sz - virt_addr) / RTE_PGSIZE_2M;
-        pa[i] = mcfg->memseg[memseg_id].mfn[mfn_id] * page_size;
-    }
+	uint32_t i;
+	uint64_t virt_addr, mfn_id;
+	struct rte_mem_config *mcfg;
+	uint32_t page_size = getpagesize();
+
+	/* get pointer to global configuration */
+	mcfg = rte_eal_get_configuration()->mem_config;
+	virt_addr =(uintptr_t) mcfg->memseg[memseg_id].addr;
+
+	for (i = 0; i != pg_num; i++) {
+		mfn_id = ((uintptr_t)va + i * pg_sz - virt_addr) / RTE_PGSIZE_2M;
+		pa[i] = mcfg->memseg[memseg_id].mfn[mfn_id] * page_size;
+	}
 }
 
 /* create the mempool for supporting Dom0 */
 struct rte_mempool *
 rte_dom0_mempool_create(const char *name, unsigned elt_num, unsigned elt_size,
-           unsigned cache_size, unsigned private_data_size,
-           rte_mempool_ctor_t *mp_init, void *mp_init_arg,
-           rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg,
-           int socket_id, unsigned flags)
+	unsigned cache_size, unsigned private_data_size,
+	rte_mempool_ctor_t *mp_init, void *mp_init_arg,
+	rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg,
+	int socket_id, unsigned flags)
 {
 	struct rte_mempool *mp = NULL;
 	phys_addr_t *pa;
diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index 60369cf..f592dc7 100644
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -347,9 +347,9 @@ rte_mempool_xmem_size(uint32_t elt_num, size_t elt_sz, uint32_t pg_shift)
  */
 static void
 mempool_lelem_iter(void *arg, __rte_unused void *start, void *end,
-        __rte_unused uint32_t idx)
+	__rte_unused uint32_t idx)
 {
-        *(uintptr_t *)arg = (uintptr_t)end;
+	*(uintptr_t *)arg = (uintptr_t)end;
 }
 
 ssize_t
@@ -521,8 +521,8 @@ rte_mempool_xmem_create(const char *name, unsigned n, unsigned elt_size,
 
 	/*
 	 * If user provided an external memory buffer, then use it to
-	 * store mempool objects. Otherwise reserve memzone big enough to
-	 * hold mempool header and metadata plus mempool objects.
+	 * store mempool objects. Otherwise reserve a memzone that is large
+	 * enough to hold mempool header and metadata plus mempool objects.
 	 */
 	mempool_size = MEMPOOL_HEADER_SIZE(mp, pg_num) + private_data_size;
 	if (vaddr == NULL)
@@ -543,7 +543,7 @@ rte_mempool_xmem_create(const char *name, unsigned n, unsigned elt_size,
 
 	/*
 	 * no more memory: in this case we loose previously reserved
-	 * space for the as we cannot free it
+	 * space for the ring as we cannot free it
 	 */
 	if (mz == NULL) {
 		rte_free(te);
diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index cdb8f67..649c27d 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -109,6 +109,9 @@ struct rte_mempool_cache {
 } __rte_cache_aligned;
 #endif /* RTE_MEMPOOL_CACHE_MAX_SIZE > 0 */
 
+/**
+ * A structure that stores the size of mempool elements.
+ */
 struct rte_mempool_objsz {
 	uint32_t elt_size;     /**< Size of an element. */
 	uint32_t header_size;  /**< Size of header (before elt). */
@@ -206,7 +209,7 @@ struct rte_mempool {
 	uintptr_t   elt_va_end;
 	/**< Virtual address of the <size + 1> mempool object. */
 	phys_addr_t elt_pa[MEMPOOL_PG_NUM_DEFAULT];
-	/**< Array of physical pages addresses for the mempool objects buffer. */
+	/**< Array of physical page addresses for the mempool objects buffer. */
 
 }  __rte_cache_aligned;
 
@@ -217,6 +220,7 @@ struct rte_mempool {
 
 /**
  * @internal When debug is enabled, store some statistics.
+ *
  * @param mp
  *   Pointer to the memory pool.
  * @param name
@@ -237,18 +241,19 @@ struct rte_mempool {
 #endif
 
 /**
- * Calculates size of the mempool header.
+ * Calculate the size of the mempool header.
+ *
  * @param mp
  *   Pointer to the memory pool.
  * @param pgn
- *   Number of page used to store mempool objects.
+ *   Number of pages used to store mempool objects.
  */
 #define	MEMPOOL_HEADER_SIZE(mp, pgn)	(sizeof(*(mp)) + \
 	RTE_ALIGN_CEIL(((pgn) - RTE_DIM((mp)->elt_pa)) * \
 	sizeof ((mp)->elt_pa[0]), RTE_CACHE_LINE_SIZE))
 
 /**
- * Returns TRUE if whole mempool is allocated in one contiguous block of memory.
+ * Return true if the whole mempool is in contiguous memory.
  */
 #define	MEMPOOL_IS_CONTIG(mp)                      \
 	((mp)->pg_num == MEMPOOL_PG_NUM_DEFAULT && \
@@ -376,21 +381,25 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 #endif /* RTE_LIBRTE_MEMPOOL_DEBUG */
 
 /**
- * An mempool's object iterator callback function.
+ * A mempool object iterator callback function.
  */
 typedef void (*rte_mempool_obj_iter_t)(void * /*obj_iter_arg*/,
 	void * /*obj_start*/,
 	void * /*obj_end*/,
 	uint32_t /*obj_index */);
 
-/*
- * Iterates across objects of the given size and alignment in the
+/**
+ * Call a function for each mempool object in a memory chunk
+ *
+ * Iterate across objects of the given size and alignment in the
  * provided chunk of memory. The given memory buffer can consist of
  * disjoint physical pages.
- * For each object calls the provided callback (if any).
- * Used to populate mempool, walk through all elements of the mempool,
- * estimate how many elements of the given size could be created in the given
- * memory buffer.
+ *
+ * For each object, calls the provided callback (if any). This function
+ * is used to populate mempool, walk through all elements of the
+ * mempool, estimate how many elements of the given size could be
+ * created in the given memory buffer.
+ *
  * @param vaddr
  *   Virtual address of the memory buffer.
  * @param elt_num
@@ -398,7 +407,7 @@ typedef void (*rte_mempool_obj_iter_t)(void * /*obj_iter_arg*/,
  * @param elt_sz
  *   Size of each object.
  * @param paddr
- *   Array of phyiscall addresses of the pages that comprises given memory
+ *   Array of physical addresses of the pages that comprises given memory
  *   buffer.
  * @param pg_num
  *   Number of elements in the paddr array.
@@ -407,7 +416,7 @@ typedef void (*rte_mempool_obj_iter_t)(void * /*obj_iter_arg*/,
  * @param obj_iter
  *   Object iterator callback function (could be NULL).
  * @param obj_iter_arg
- *   User defined Prameter for the object iterator callback function.
+ *   User defined parameter for the object iterator callback function.
  *
  * @return
  *   Number of objects iterated through.
@@ -437,7 +446,7 @@ typedef void (rte_mempool_obj_ctor_t)(struct rte_mempool *, void *,
 typedef void (rte_mempool_ctor_t)(struct rte_mempool *, void *);
 
 /**
- * Creates a new mempool named *name* in memory.
+ * Create a new mempool named *name* in memory.
  *
  * This function uses ``memzone_reserve()`` to allocate memory. The
  * pool contains n elements of elt_size. Its size is set to n.
@@ -525,14 +534,14 @@ rte_mempool_create(const char *name, unsigned n, unsigned elt_size,
 		   int socket_id, unsigned flags);
 
 /**
- * Creates a new mempool named *name* in memory.
+ * Create a new mempool named *name* in memory.
  *
  * This function uses ``memzone_reserve()`` to allocate memory. The
  * pool contains n elements of elt_size. Its size is set to n.
  * Depending on the input parameters, mempool elements can be either allocated
  * together with the mempool header, or an externally provided memory buffer
  * could be used to store mempool objects. In later case, that external
- * memory buffer can consist of set of disjoint phyiscal pages.
+ * memory buffer can consist of set of disjoint physical pages.
  *
  * @param name
  *   The name of the mempool.
@@ -601,7 +610,7 @@ rte_mempool_create(const char *name, unsigned n, unsigned elt_size,
  *   Virtual address of the externally allocated memory buffer.
  *   Will be used to store mempool objects.
  * @param paddr
- *   Array of phyiscall addresses of the pages that comprises given memory
+ *   Array of physical addresses of the pages that comprises given memory
  *   buffer.
  * @param pg_num
  *   Number of elements in the paddr array.
@@ -627,12 +636,12 @@ rte_mempool_xmem_create(const char *name, unsigned n, unsigned elt_size,
 
 #ifdef RTE_LIBRTE_XEN_DOM0
 /**
- * Creates a new mempool named *name* in memory on Xen Dom0.
+ * Create a new mempool named *name* in memory on Xen Dom0.
  *
  * This function uses ``rte_mempool_xmem_create()`` to allocate memory. The
  * pool contains n elements of elt_size. Its size is set to n.
  * All elements of the mempool are allocated together with the mempool header,
- * and memory buffer can consist of set of disjoint phyiscal pages.
+ * and memory buffer can consist of set of disjoint physical pages.
  *
  * @param name
  *   The name of the mempool.
@@ -1305,8 +1314,11 @@ void rte_mempool_list_dump(FILE *f);
 struct rte_mempool *rte_mempool_lookup(const char *name);
 
 /**
+ * Get the header, trailer and total size of a mempool element.
+ *
  * Given a desired size of the mempool element and mempool flags,
- * caluclates header, trailer, body and total sizes of the mempool object.
+ * calculates header, trailer, body and total sizes of the mempool object.
+ *
  * @param elt_size
  *   The size of each element.
  * @param flags
@@ -1320,11 +1332,16 @@ uint32_t rte_mempool_calc_obj_size(uint32_t elt_size, uint32_t flags,
 	struct rte_mempool_objsz *sz);
 
 /**
- * Calculate maximum amount of memory required to store given number of objects.
- * Assumes that the memory buffer will be aligned at page boundary.
- * Note, that if object size is bigger then page size, then it assumes that
- * we have a subsets of physically continuous  pages big enough to store
- * at least one object.
+ * Get the size of memory required to store mempool elements.
+ *
+ * Calculate the maximum amount of memory required to store given number
+ * of objects. Assume that the memory buffer will be aligned at page
+ * boundary.
+ *
+ * Note that if object size is bigger then page size, then it assumes
+ * that pages are grouped in subsets of physically continuous pages big
+ * enough to store at least one object.
+ *
  * @param elt_num
  *   Number of elements.
  * @param elt_sz
@@ -1338,8 +1355,11 @@ size_t rte_mempool_xmem_size(uint32_t elt_num, size_t elt_sz,
 	uint32_t pg_shift);
 
 /**
+ * Get the size of memory required to store mempool elements.
+ *
  * Calculate how much memory would be actually required with the given
  * memory footprint to store required number of objects.
+ *
  * @param vaddr
  *   Virtual address of the externally allocated memory buffer.
  *   Will be used to store mempool objects.
@@ -1348,17 +1368,17 @@ size_t rte_mempool_xmem_size(uint32_t elt_num, size_t elt_sz,
  * @param elt_sz
  *   The size of each element.
  * @param paddr
- *   Array of phyiscall addresses of the pages that comprises given memory
+ *   Array of physical addresses of the pages that comprises given memory
  *   buffer.
  * @param pg_num
  *   Number of elements in the paddr array.
  * @param pg_shift
  *   LOG2 of the physical pages size.
  * @return
- *   Number of bytes needed to store given number of objects,
- *   aligned to the given page size.
- *   If provided memory buffer is not big enough:
- *   (-1) * actual number of elemnts that can be stored in that buffer.
+ *   On success, the number of bytes needed to store given number of
+ *   objects, aligned to the given page size. If the provided memory
+ *   buffer is too small, return a negative value whose absolute value
+ *   is the actual number of elements that can be stored in that buffer.
  */
 ssize_t rte_mempool_xmem_usage(void *vaddr, uint32_t elt_num, size_t elt_sz,
 	const phys_addr_t paddr[], uint32_t pg_num, uint32_t pg_shift);
-- 
2.1.4

[dpdk-dev] [PATCH v2 0/3] mempool: clean-up

[Olivier Matz]

These 3 patches try to make mempool code easier to read, they
have no functional impact.

Changes in v2:
- fix compilation between patch 1 and 2

Olivier Matz (3):
  mempool: introduce objhdr structure for object headers
  mempool: introduce objtlr structure for object trailers
  mempool: fix typos, indentation, and doxygen style

 lib/librte_mempool/rte_dom0_mempool.c |  36 +++----
 lib/librte_mempool/rte_mempool.c      |  22 ++--
 lib/librte_mempool/rte_mempool.h      | 188 ++++++++++++++++++----------------
 3 files changed, 128 insertions(+), 118 deletions(-)

-- 
2.1.4

[dpdk-dev] [PATCH v2 1/3] mempool: introduce objhdr structure for object headers

[Olivier Matz]

Each object stored in mempools are prefixed by a header, allowing for
instance to retrieve the mempool pointer from the object. When debug is
enabled, a cookie is also added in this header that helps to detect
corruptions and double-frees.

Introduce a structure that materializes the content of this header,
and will simplify future patches adding things in this header.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
 lib/librte_mempool/rte_mempool.c |  8 ++---
 lib/librte_mempool/rte_mempool.h | 76 ++++++++++++++++------------------------
 2 files changed, 35 insertions(+), 49 deletions(-)

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index 190cfd9..b2d8700 100644
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -130,16 +130,16 @@ static void
 mempool_add_elem(struct rte_mempool *mp, void *obj, uint32_t obj_idx,
 	rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg)
 {
-	struct rte_mempool **mpp;
+	struct rte_mempool_objhdr *hdr;
 
 	obj = (char *)obj + mp->header_size;
 
 	/* set mempool ptr in header */
-	mpp = __mempool_from_obj(obj);
-	*mpp = mp;
+	hdr = (struct rte_mempool_objhdr *)((char *)obj - sizeof(*hdr));
+	hdr->mp = mp;
 
 #ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-	__mempool_write_header_cookie(obj, 1);
+	hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE2;
 	__mempool_write_trailer_cookie(obj);
 #endif
 	/* call the initializer */
diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index bc2bae0..b047810 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -140,6 +140,21 @@ struct rte_mempool_objsz {
 #define	MEMPOOL_PG_NUM_DEFAULT	1
 
 /**
+ * Mempool object header structure
+ *
+ * Each object stored in mempools are prefixed by this header structure,
+ * it allows to retrieve the mempool pointer from the object. When debug
+ * is enabled, a cookie is also added in this structure preventing
+ * corruptions and double-frees.
+ */
+struct rte_mempool_objhdr {
+	struct rte_mempool *mp;          /**< The mempool owning the object. */
+#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
+	uint64_t cookie;                 /**< Debug cookie. */
+#endif
+};
+
+/**
  * The RTE mempool structure.
  */
 struct rte_mempool {
@@ -227,24 +242,11 @@ struct rte_mempool {
 	((mp)->pg_num == MEMPOOL_PG_NUM_DEFAULT && \
 	(mp)->phys_addr == (mp)->elt_pa[0])
 
-/**
- * @internal Get a pointer to a mempool pointer in the object header.
- * @param obj
- *   Pointer to object.
- * @return
- *   The pointer to the mempool from which the object was allocated.
- */
-static inline struct rte_mempool **__mempool_from_obj(void *obj)
+/* return the header of a mempool object (internal) */
+static inline struct rte_mempool_objhdr *__mempool_get_header(void *obj)
 {
-	struct rte_mempool **mpp;
-	unsigned off;
-
-	off = sizeof(struct rte_mempool *);
-#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-	off += sizeof(uint64_t);
-#endif
-	mpp = (struct rte_mempool **)((char *)obj - off);
-	return mpp;
+	return (struct rte_mempool_objhdr *)((char *)obj -
+		sizeof(struct rte_mempool_objhdr));
 }
 
 /**
@@ -256,36 +258,18 @@ static inline struct rte_mempool **__mempool_from_obj(void *obj)
  * @return
  *   A pointer to the mempool structure.
  */
-static inline const struct rte_mempool *rte_mempool_from_obj(void *obj)
+static inline struct rte_mempool *rte_mempool_from_obj(void *obj)
 {
-	struct rte_mempool * const *mpp;
-	mpp = __mempool_from_obj(obj);
-	return *mpp;
+	struct rte_mempool_objhdr *hdr = __mempool_get_header(obj);
+	return hdr->mp;
 }
 
 #ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-/* get header cookie value */
-static inline uint64_t __mempool_read_header_cookie(const void *obj)
-{
-	return *(const uint64_t *)((const char *)obj - sizeof(uint64_t));
-}
-
 /* get trailer cookie value */
 static inline uint64_t __mempool_read_trailer_cookie(void *obj)
 {
-	struct rte_mempool **mpp = __mempool_from_obj(obj);
-	return *(uint64_t *)((char *)obj + (*mpp)->elt_size);
-}
-
-/* write header cookie value */
-static inline void __mempool_write_header_cookie(void *obj, int free)
-{
-	uint64_t *cookie_p;
-	cookie_p = (uint64_t *)((char *)obj - sizeof(uint64_t));
-	if (free == 0)
-		*cookie_p = RTE_MEMPOOL_HEADER_COOKIE1;
-	else
-		*cookie_p = RTE_MEMPOOL_HEADER_COOKIE2;
+	struct rte_mempool *mp = rte_mempool_from_obj(obj);
+	return *(uint64_t *)((char *)obj + mp->elt_size);
 
 }
 
@@ -293,8 +277,8 @@ static inline void __mempool_write_header_cookie(void *obj, int free)
 static inline void __mempool_write_trailer_cookie(void *obj)
 {
 	uint64_t *cookie_p;
-	struct rte_mempool **mpp = __mempool_from_obj(obj);
-	cookie_p = (uint64_t *)((char *)obj + (*mpp)->elt_size);
+	struct rte_mempool *mp = rte_mempool_from_obj(obj);
+	cookie_p = (uint64_t *)((char *)obj + mp->elt_size);
 	*cookie_p = RTE_MEMPOOL_TRAILER_COOKIE;
 }
 #endif /* RTE_LIBRTE_MEMPOOL_DEBUG */
@@ -321,6 +305,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					   void * const *obj_table_const,
 					   unsigned n, int free)
 {
+	struct rte_mempool_objhdr *hdr;
 	uint64_t cookie;
 	void *tmp;
 	void *obj;
@@ -338,7 +323,8 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 			rte_panic("MEMPOOL: object is owned by another "
 				  "mempool\n");
 
-		cookie = __mempool_read_header_cookie(obj);
+		hdr = __mempool_get_header(obj);
+		cookie = hdr->cookie;
 
 		if (free == 0) {
 			if (cookie != RTE_MEMPOOL_HEADER_COOKIE1) {
@@ -348,7 +334,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					obj, (const void *) mp, cookie);
 				rte_panic("MEMPOOL: bad header cookie (put)\n");
 			}
-			__mempool_write_header_cookie(obj, 1);
+			hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE2;
 		}
 		else if (free == 1) {
 			if (cookie != RTE_MEMPOOL_HEADER_COOKIE2) {
@@ -358,7 +344,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					obj, (const void *) mp, cookie);
 				rte_panic("MEMPOOL: bad header cookie (get)\n");
 			}
-			__mempool_write_header_cookie(obj, 0);
+			hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE1;
 		}
 		else if (free == 2) {
 			if (cookie != RTE_MEMPOOL_HEADER_COOKIE1 &&
-- 
2.1.4

[dpdk-dev] [PATCH v2 2/3] mempool: introduce objtlr structure for object trailers

[Olivier Matz]

Each object stored in mempools are suffixed by a trailer, storing
a cookie in debug mode which help to detect memory corruptions.

Like for headers, introduce a structure that materializes the content of
this trailer.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
 lib/librte_mempool/rte_mempool.c |  4 +++-
 lib/librte_mempool/rte_mempool.h | 42 +++++++++++++++++++++-------------------
 2 files changed, 25 insertions(+), 21 deletions(-)

diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index b2d8700..60369cf 100644
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -131,6 +131,7 @@ mempool_add_elem(struct rte_mempool *mp, void *obj, uint32_t obj_idx,
 	rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg)
 {
 	struct rte_mempool_objhdr *hdr;
+	struct rte_mempool_objtlr *tlr __rte_unused;
 
 	obj = (char *)obj + mp->header_size;
 
@@ -140,7 +141,8 @@ mempool_add_elem(struct rte_mempool *mp, void *obj, uint32_t obj_idx,
 
 #ifdef RTE_LIBRTE_MEMPOOL_DEBUG
 	hdr->cookie = RTE_MEMPOOL_HEADER_COOKIE2;
-	__mempool_write_trailer_cookie(obj);
+	tlr = __mempool_get_trailer(obj);
+	tlr->cookie = RTE_MEMPOOL_TRAILER_COOKIE;
 #endif
 	/* call the initializer */
 	if (obj_init)
diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index b047810..ec1bb2e 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -155,6 +155,18 @@ struct rte_mempool_objhdr {
 };
 
 /**
+ * Mempool object trailer structure
+ *
+ * In debug mode, each object stored in mempools are suffixed by this
+ * trailer structure containing a cookie preventing memory corruptions.
+ */
+struct rte_mempool_objtlr {
+#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
+	uint64_t cookie;                 /**< Debug cookie. */
+#endif
+};
+
+/**
  * The RTE mempool structure.
  */
 struct rte_mempool {
@@ -249,6 +261,13 @@ static inline struct rte_mempool_objhdr *__mempool_get_header(void *obj)
 		sizeof(struct rte_mempool_objhdr));
 }
 
+/* return the trailer of a mempool object (internal) */
+static inline struct rte_mempool_objtlr *__mempool_get_trailer(void *obj)
+{
+	return (struct rte_mempool_objtlr *)((char *)obj -
+		sizeof(struct rte_mempool_objtlr));
+}
+
 /**
  * Return a pointer to the mempool owning this object.
  *
@@ -264,25 +283,6 @@ static inline struct rte_mempool *rte_mempool_from_obj(void *obj)
 	return hdr->mp;
 }
 
-#ifdef RTE_LIBRTE_MEMPOOL_DEBUG
-/* get trailer cookie value */
-static inline uint64_t __mempool_read_trailer_cookie(void *obj)
-{
-	struct rte_mempool *mp = rte_mempool_from_obj(obj);
-	return *(uint64_t *)((char *)obj + mp->elt_size);
-
-}
-
-/* write trailer cookie value */
-static inline void __mempool_write_trailer_cookie(void *obj)
-{
-	uint64_t *cookie_p;
-	struct rte_mempool *mp = rte_mempool_from_obj(obj);
-	cookie_p = (uint64_t *)((char *)obj + mp->elt_size);
-	*cookie_p = RTE_MEMPOOL_TRAILER_COOKIE;
-}
-#endif /* RTE_LIBRTE_MEMPOOL_DEBUG */
-
 /**
  * @internal Check and update cookies or panic.
  *
@@ -306,6 +306,7 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 					   unsigned n, int free)
 {
 	struct rte_mempool_objhdr *hdr;
+	struct rte_mempool_objtlr *tlr;
 	uint64_t cookie;
 	void *tmp;
 	void *obj;
@@ -356,7 +357,8 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 				rte_panic("MEMPOOL: bad header cookie (audit)\n");
 			}
 		}
-		cookie = __mempool_read_trailer_cookie(obj);
+		tlr = __mempool_get_trailer(obj);
+		cookie = tlr->cookie;
 		if (cookie != RTE_MEMPOOL_TRAILER_COOKIE) {
 			rte_log_set_history(0);
 			RTE_LOG(CRIT, MEMPOOL,
-- 
2.1.4

[dpdk-dev] [PATCH v2 3/3] mempool: fix typos, indentation, and doxygen style

[Olivier Matz]

Do some cosmetic clean-up.

Signed-off-by: Olivier Matz <olivier.matz@6wind.com>
---
 lib/librte_mempool/rte_dom0_mempool.c | 36 ++++++++--------
 lib/librte_mempool/rte_mempool.c      | 10 ++---
 lib/librte_mempool/rte_mempool.h      | 80 ++++++++++++++++++++++-------------
 3 files changed, 73 insertions(+), 53 deletions(-)

diff --git a/lib/librte_mempool/rte_dom0_mempool.c b/lib/librte_mempool/rte_dom0_mempool.c
index 8900171..a313b3f 100644
--- a/lib/librte_mempool/rte_dom0_mempool.c
+++ b/lib/librte_mempool/rte_dom0_mempool.c
@@ -61,30 +61,30 @@
 
 static void
 get_phys_map(void *va, phys_addr_t pa[], uint32_t pg_num,
-            uint32_t pg_sz, uint32_t memseg_id)
+	uint32_t pg_sz, uint32_t memseg_id)
 {
-    uint32_t i;
-    uint64_t virt_addr, mfn_id;
-    struct rte_mem_config *mcfg;
-    uint32_t page_size = getpagesize();
-
-    /* get pointer to global configuration */
-    mcfg = rte_eal_get_configuration()->mem_config;
-    virt_addr =(uintptr_t) mcfg->memseg[memseg_id].addr;
-
-    for (i = 0; i != pg_num; i++) {
-        mfn_id = ((uintptr_t)va + i * pg_sz - virt_addr) / RTE_PGSIZE_2M;
-        pa[i] = mcfg->memseg[memseg_id].mfn[mfn_id] * page_size;
-    }
+	uint32_t i;
+	uint64_t virt_addr, mfn_id;
+	struct rte_mem_config *mcfg;
+	uint32_t page_size = getpagesize();
+
+	/* get pointer to global configuration */
+	mcfg = rte_eal_get_configuration()->mem_config;
+	virt_addr =(uintptr_t) mcfg->memseg[memseg_id].addr;
+
+	for (i = 0; i != pg_num; i++) {
+		mfn_id = ((uintptr_t)va + i * pg_sz - virt_addr) / RTE_PGSIZE_2M;
+		pa[i] = mcfg->memseg[memseg_id].mfn[mfn_id] * page_size;
+	}
 }
 
 /* create the mempool for supporting Dom0 */
 struct rte_mempool *
 rte_dom0_mempool_create(const char *name, unsigned elt_num, unsigned elt_size,
-           unsigned cache_size, unsigned private_data_size,
-           rte_mempool_ctor_t *mp_init, void *mp_init_arg,
-           rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg,
-           int socket_id, unsigned flags)
+	unsigned cache_size, unsigned private_data_size,
+	rte_mempool_ctor_t *mp_init, void *mp_init_arg,
+	rte_mempool_obj_ctor_t *obj_init, void *obj_init_arg,
+	int socket_id, unsigned flags)
 {
 	struct rte_mempool *mp = NULL;
 	phys_addr_t *pa;
diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c
index 60369cf..f592dc7 100644
--- a/lib/librte_mempool/rte_mempool.c
+++ b/lib/librte_mempool/rte_mempool.c
@@ -347,9 +347,9 @@ rte_mempool_xmem_size(uint32_t elt_num, size_t elt_sz, uint32_t pg_shift)
  */
 static void
 mempool_lelem_iter(void *arg, __rte_unused void *start, void *end,
-        __rte_unused uint32_t idx)
+	__rte_unused uint32_t idx)
 {
-        *(uintptr_t *)arg = (uintptr_t)end;
+	*(uintptr_t *)arg = (uintptr_t)end;
 }
 
 ssize_t
@@ -521,8 +521,8 @@ rte_mempool_xmem_create(const char *name, unsigned n, unsigned elt_size,
 
 	/*
 	 * If user provided an external memory buffer, then use it to
-	 * store mempool objects. Otherwise reserve memzone big enough to
-	 * hold mempool header and metadata plus mempool objects.
+	 * store mempool objects. Otherwise reserve a memzone that is large
+	 * enough to hold mempool header and metadata plus mempool objects.
 	 */
 	mempool_size = MEMPOOL_HEADER_SIZE(mp, pg_num) + private_data_size;
 	if (vaddr == NULL)
@@ -543,7 +543,7 @@ rte_mempool_xmem_create(const char *name, unsigned n, unsigned elt_size,
 
 	/*
 	 * no more memory: in this case we loose previously reserved
-	 * space for the as we cannot free it
+	 * space for the ring as we cannot free it
 	 */
 	if (mz == NULL) {
 		rte_free(te);
diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h
index ec1bb2e..a8054e1 100644
--- a/lib/librte_mempool/rte_mempool.h
+++ b/lib/librte_mempool/rte_mempool.h
@@ -109,6 +109,9 @@ struct rte_mempool_cache {
 } __rte_cache_aligned;
 #endif /* RTE_MEMPOOL_CACHE_MAX_SIZE > 0 */
 
+/**
+ * A structure that stores the size of mempool elements.
+ */
 struct rte_mempool_objsz {
 	uint32_t elt_size;     /**< Size of an element. */
 	uint32_t header_size;  /**< Size of header (before elt). */
@@ -206,7 +209,7 @@ struct rte_mempool {
 	uintptr_t   elt_va_end;
 	/**< Virtual address of the <size + 1> mempool object. */
 	phys_addr_t elt_pa[MEMPOOL_PG_NUM_DEFAULT];
-	/**< Array of physical pages addresses for the mempool objects buffer. */
+	/**< Array of physical page addresses for the mempool objects buffer. */
 
 }  __rte_cache_aligned;
 
@@ -217,6 +220,7 @@ struct rte_mempool {
 
 /**
  * @internal When debug is enabled, store some statistics.
+ *
  * @param mp
  *   Pointer to the memory pool.
  * @param name
@@ -237,18 +241,19 @@ struct rte_mempool {
 #endif
 
 /**
- * Calculates size of the mempool header.
+ * Calculate the size of the mempool header.
+ *
  * @param mp
  *   Pointer to the memory pool.
  * @param pgn
- *   Number of page used to store mempool objects.
+ *   Number of pages used to store mempool objects.
  */
 #define	MEMPOOL_HEADER_SIZE(mp, pgn)	(sizeof(*(mp)) + \
 	RTE_ALIGN_CEIL(((pgn) - RTE_DIM((mp)->elt_pa)) * \
 	sizeof ((mp)->elt_pa[0]), RTE_CACHE_LINE_SIZE))
 
 /**
- * Returns TRUE if whole mempool is allocated in one contiguous block of memory.
+ * Return true if the whole mempool is in contiguous memory.
  */
 #define	MEMPOOL_IS_CONTIG(mp)                      \
 	((mp)->pg_num == MEMPOOL_PG_NUM_DEFAULT && \
@@ -376,21 +381,25 @@ static inline void __mempool_check_cookies(const struct rte_mempool *mp,
 #endif /* RTE_LIBRTE_MEMPOOL_DEBUG */
 
 /**
- * An mempool's object iterator callback function.
+ * A mempool object iterator callback function.
  */
 typedef void (*rte_mempool_obj_iter_t)(void * /*obj_iter_arg*/,
 	void * /*obj_start*/,
 	void * /*obj_end*/,
 	uint32_t /*obj_index */);
 
-/*
- * Iterates across objects of the given size and alignment in the
+/**
+ * Call a function for each mempool object in a memory chunk
+ *
+ * Iterate across objects of the given size and alignment in the
  * provided chunk of memory. The given memory buffer can consist of
  * disjoint physical pages.
- * For each object calls the provided callback (if any).
- * Used to populate mempool, walk through all elements of the mempool,
- * estimate how many elements of the given size could be created in the given
- * memory buffer.
+ *
+ * For each object, calls the provided callback (if any). This function
+ * is used to populate mempool, walk through all elements of the
+ * mempool, estimate how many elements of the given size could be
+ * created in the given memory buffer.
+ *
  * @param vaddr
  *   Virtual address of the memory buffer.
  * @param elt_num
@@ -398,7 +407,7 @@ typedef void (*rte_mempool_obj_iter_t)(void * /*obj_iter_arg*/,
  * @param elt_sz
  *   Size of each object.
  * @param paddr
- *   Array of phyiscall addresses of the pages that comprises given memory
+ *   Array of physical addresses of the pages that comprises given memory
  *   buffer.
  * @param pg_num
  *   Number of elements in the paddr array.
@@ -407,7 +416,7 @@ typedef void (*rte_mempool_obj_iter_t)(void * /*obj_iter_arg*/,
  * @param obj_iter
  *   Object iterator callback function (could be NULL).
  * @param obj_iter_arg
- *   User defined Prameter for the object iterator callback function.
+ *   User defined parameter for the object iterator callback function.
  *
  * @return
  *   Number of objects iterated through.
@@ -437,7 +446,7 @@ typedef void (rte_mempool_obj_ctor_t)(struct rte_mempool *, void *,
 typedef void (rte_mempool_ctor_t)(struct rte_mempool *, void *);
 
 /**
- * Creates a new mempool named *name* in memory.
+ * Create a new mempool named *name* in memory.
  *
  * This function uses ``memzone_reserve()`` to allocate memory. The
  * pool contains n elements of elt_size. Its size is set to n.
@@ -525,14 +534,14 @@ rte_mempool_create(const char *name, unsigned n, unsigned elt_size,
 		   int socket_id, unsigned flags);
 
 /**
- * Creates a new mempool named *name* in memory.
+ * Create a new mempool named *name* in memory.
  *
  * This function uses ``memzone_reserve()`` to allocate memory. The
  * pool contains n elements of elt_size. Its size is set to n.
  * Depending on the input parameters, mempool elements can be either allocated
  * together with the mempool header, or an externally provided memory buffer
  * could be used to store mempool objects. In later case, that external
- * memory buffer can consist of set of disjoint phyiscal pages.
+ * memory buffer can consist of set of disjoint physical pages.
  *
  * @param name
  *   The name of the mempool.
@@ -601,7 +610,7 @@ rte_mempool_create(const char *name, unsigned n, unsigned elt_size,
  *   Virtual address of the externally allocated memory buffer.
  *   Will be used to store mempool objects.
  * @param paddr
- *   Array of phyiscall addresses of the pages that comprises given memory
+ *   Array of physical addresses of the pages that comprises given memory
  *   buffer.
  * @param pg_num
  *   Number of elements in the paddr array.
@@ -627,12 +636,12 @@ rte_mempool_xmem_create(const char *name, unsigned n, unsigned elt_size,
 
 #ifdef RTE_LIBRTE_XEN_DOM0
 /**
- * Creates a new mempool named *name* in memory on Xen Dom0.
+ * Create a new mempool named *name* in memory on Xen Dom0.
  *
  * This function uses ``rte_mempool_xmem_create()`` to allocate memory. The
  * pool contains n elements of elt_size. Its size is set to n.
  * All elements of the mempool are allocated together with the mempool header,
- * and memory buffer can consist of set of disjoint phyiscal pages.
+ * and memory buffer can consist of set of disjoint physical pages.
  *
  * @param name
  *   The name of the mempool.
@@ -1305,8 +1314,11 @@ void rte_mempool_list_dump(FILE *f);
 struct rte_mempool *rte_mempool_lookup(const char *name);
 
 /**
+ * Get the header, trailer and total size of a mempool element.
+ *
  * Given a desired size of the mempool element and mempool flags,
- * caluclates header, trailer, body and total sizes of the mempool object.
+ * calculates header, trailer, body and total sizes of the mempool object.
+ *
  * @param elt_size
  *   The size of each element.
  * @param flags
@@ -1322,11 +1334,16 @@ uint32_t rte_mempool_calc_obj_size(uint32_t elt_size, uint32_t flags,
 	struct rte_mempool_objsz *sz);
 
 /**
- * Calculate maximum amount of memory required to store given number of objects.
- * Assumes that the memory buffer will be aligned at page boundary.
- * Note, that if object size is bigger then page size, then it assumes that
- * we have a subsets of physically continuous  pages big enough to store
- * at least one object.
+ * Get the size of memory required to store mempool elements.
+ *
+ * Calculate the maximum amount of memory required to store given number
+ * of objects. Assume that the memory buffer will be aligned at page
+ * boundary.
+ *
+ * Note that if object size is bigger then page size, then it assumes
+ * that pages are grouped in subsets of physically continuous pages big
+ * enough to store at least one object.
+ *
  * @param elt_num
  *   Number of elements.
  * @param elt_sz
@@ -1340,8 +1357,11 @@ size_t rte_mempool_xmem_size(uint32_t elt_num, size_t elt_sz,
 	uint32_t pg_shift);
 
 /**
+ * Get the size of memory required to store mempool elements.
+ *
  * Calculate how much memory would be actually required with the given
  * memory footprint to store required number of objects.
+ *
  * @param vaddr
  *   Virtual address of the externally allocated memory buffer.
  *   Will be used to store mempool objects.
@@ -1350,17 +1370,17 @@ size_t rte_mempool_xmem_size(uint32_t elt_num, size_t elt_sz,
  * @param elt_sz
  *   The size of each element.
  * @param paddr
- *   Array of phyiscall addresses of the pages that comprises given memory
+ *   Array of physical addresses of the pages that comprises given memory
  *   buffer.
  * @param pg_num
  *   Number of elements in the paddr array.
  * @param pg_shift
  *   LOG2 of the physical pages size.
  * @return
- *   Number of bytes needed to store given number of objects,
- *   aligned to the given page size.
- *   If provided memory buffer is not big enough:
- *   (-1) * actual number of elemnts that can be stored in that buffer.
+ *   On success, the number of bytes needed to store given number of
+ *   objects, aligned to the given page size. If the provided memory
+ *   buffer is too small, return a negative value whose absolute value
+ *   is the actual number of elements that can be stored in that buffer.
  */
 ssize_t rte_mempool_xmem_usage(void *vaddr, uint32_t elt_num, size_t elt_sz,
 	const phys_addr_t paddr[], uint32_t pg_num, uint32_t pg_shift);
-- 
2.1.4

Re: [dpdk-dev] [PATCH v2 0/3] mempool: clean-up

[Thomas Monjalon]

2015-06-19 18:16, Olivier Matz:
> These 3 patches try to make mempool code easier to read, they
> have no functional impact.
> 
> Changes in v2:
> - fix compilation between patch 1 and 2
> 
> Olivier Matz (3):
>   mempool: introduce objhdr structure for object headers
>   mempool: introduce objtlr structure for object trailers
>   mempool: fix typos, indentation, and doxygen style

Applied, thanks