On 7/19/19 4:38 PM, Olivier Matz wrote:
When using iova contiguous memory and objets smaller than page size, ensure that objects are not located across several pages.
It looks like as an attempt to make exception a generic rule and I think it is not a good idea. mempool has a notion of IOVA contiguous/non-contiguous objects depending if PA or VA. rte_mempool_op_populate_default() gets a memory chunk which is contiguous in VA and, if iova is not bad, IOVA-contiguous. The patch always enforces page boundaries even if it is not required. For example, if memory chunk is IOVA_PA contiguous, the patch could result in holes and extra memory usage
Signed-off-by: Vamsi Krishna Attunuru <vattun...@marvell.com> Signed-off-by: Olivier Matz <olivier.m...@6wind.com> --- lib/librte_mempool/rte_mempool_ops_default.c | 39 ++++++++++++++++++++++++++-- 1 file changed, 37 insertions(+), 2 deletions(-) diff --git a/lib/librte_mempool/rte_mempool_ops_default.c b/lib/librte_mempool/rte_mempool_ops_default.c index 4e2bfc82d..2bbd67367 100644 --- a/lib/librte_mempool/rte_mempool_ops_default.c +++ b/lib/librte_mempool/rte_mempool_ops_default.c @@ -45,19 +45,54 @@ rte_mempool_op_calc_mem_size_default(const struct rte_mempool *mp, return mem_size; }+/* Returns -1 if object falls on a page boundary, else returns 0 */+static inline int +mempool_check_obj_bounds(void *obj, uint64_t pg_sz, size_t elt_sz) +{ + uintptr_t page_end, elt_addr = (uintptr_t)obj; + uint32_t pg_shift; + uint64_t page_mask; + + if (pg_sz == 0) + return 0; + if (elt_sz > pg_sz) + return 0; + + pg_shift = rte_bsf32(pg_sz); + page_mask = ~((1ull << pg_shift) - 1); + page_end = (elt_addr & page_mask) + pg_sz; + + if (elt_addr + elt_sz > page_end) + return -1; + + return 0; +} + int rte_mempool_op_populate_default(struct rte_mempool *mp, unsigned int max_objs, void *vaddr, rte_iova_t iova, size_t len, rte_mempool_populate_obj_cb_t *obj_cb, void *obj_cb_arg) { - size_t total_elt_sz; + size_t total_elt_sz, pg_sz; size_t off; unsigned int i; void *obj;+ rte_mempool_get_page_size(mp, &pg_sz);+ total_elt_sz = mp->header_size + mp->elt_size + mp->trailer_size;- for (off = 0, i = 0; off + total_elt_sz <= len && i < max_objs; i++) {+ for (off = 0, i = 0; i < max_objs; i++) { + /* align offset to next page start if required */ + if (mempool_check_obj_bounds((char *)vaddr + off, + pg_sz, total_elt_sz) < 0) { + off += RTE_PTR_ALIGN_CEIL((char *)vaddr + off, pg_sz) - + ((char *)vaddr + off); + } + + if (off + total_elt_sz > len) + break; + off += mp->header_size; obj = (char *)vaddr + off; obj_cb(mp, obj_cb_arg, obj,
