From 3dfb587d6785fb3a89e30ecf4503f77103b48f6a Mon Sep 17 00:00:00 2001 From: Olivier Matz Date: Wed, 8 Jan 2020 16:05:41 +0100 Subject: [PATCH] mempool: fix mempool virt populate with small chunks To populate a mempool with a virtual area, the mempool code calls rte_mempool_populate_iova() for each iova-contiguous area. It happens (rarely) that this area is too small to store one object. In this case, rte_mempool_populate_iova() returns an error, which is forwarded by rte_mempool_populate_virt(). This case should not throw an error in rte_mempool_populate_virt(). Instead, the area that is too small should just be ignored. To fix this issue, change the return value of rte_mempool_populate_iova() to -ENOBUFS when no object can be populated, so it can be ignored by the caller. As this would be an API change, add a compat wrapper to keep the current API unchanged. The wrapper will be removed for 20.11. Fixes: 354788b60cfd ("mempool: allow populating with unaligned virtual area") Cc: stable@dpdk.org Signed-off-by: Olivier Matz --- doc/guides/rel_notes/deprecation.rst | 4 ++++ lib/librte_mempool/rte_mempool.c | 28 +++++++++++++++++++++++----- lib/librte_mempool/rte_mempool.h | 5 ++++- 3 files changed, 31 insertions(+), 6 deletions(-) diff --git a/doc/guides/rel_notes/deprecation.rst b/doc/guides/rel_notes/deprecation.rst index afa94b43e2..b6e89d9a22 100644 --- a/doc/guides/rel_notes/deprecation.rst +++ b/doc/guides/rel_notes/deprecation.rst @@ -86,3 +86,7 @@ Deprecation Notices to set new power environment if power environment was already initialized. In this case the function will return -1 unless the environment is unset first (using ``rte_power_unset_env``). Other function usage scenarios will not change. + +* mempool: starting from v20.11, rte_mempool_populate_iova() will + return -ENOBUFS instead of -EINVAL when there is not enough room to + store one object. diff --git a/lib/librte_mempool/rte_mempool.c b/lib/librte_mempool/rte_mempool.c index 78d8eb941e..bda361ce64 100644 --- a/lib/librte_mempool/rte_mempool.c +++ b/lib/librte_mempool/rte_mempool.c @@ -297,8 +297,8 @@ mempool_ops_alloc_once(struct rte_mempool *mp) * zone. Return the number of objects added, or a negative value * on error. */ -int -rte_mempool_populate_iova(struct rte_mempool *mp, char *vaddr, +static int +__rte_mempool_populate_iova(struct rte_mempool *mp, char *vaddr, rte_iova_t iova, size_t len, rte_mempool_memchunk_free_cb_t *free_cb, void *opaque) { @@ -332,7 +332,7 @@ rte_mempool_populate_iova(struct rte_mempool *mp, char *vaddr, off = RTE_PTR_ALIGN_CEIL(vaddr, RTE_MEMPOOL_ALIGN) - vaddr; if (off > len) { - ret = -EINVAL; + ret = -ENOBUFS; goto fail; } @@ -343,7 +343,7 @@ rte_mempool_populate_iova(struct rte_mempool *mp, char *vaddr, /* not enough room to store one object */ if (i == 0) { - ret = -EINVAL; + ret = -ENOBUFS; goto fail; } @@ -356,6 +356,22 @@ fail: return ret; } +/* Compat wrapper, to be removed when changing the API is allowed (v20.11). */ +int +rte_mempool_populate_iova(struct rte_mempool *mp, char *vaddr, + rte_iova_t iova, size_t len, rte_mempool_memchunk_free_cb_t *free_cb, + void *opaque) +{ + int ret; + + ret = __rte_mempool_populate_iova(mp, vaddr, iova, len, free_cb, + opaque); + if (ret == -ENOBUFS) + ret = -EINVAL; + + return ret; +} + static rte_iova_t get_iova(void *addr) { @@ -406,8 +422,10 @@ rte_mempool_populate_virt(struct rte_mempool *mp, char *addr, break; } - ret = rte_mempool_populate_iova(mp, addr + off, iova, + ret = __rte_mempool_populate_iova(mp, addr + off, iova, phys_len, free_cb, opaque); + if (ret == -ENOBUFS) + continue; if (ret < 0) goto fail; /* no need to call the free callback for next chunks */ diff --git a/lib/librte_mempool/rte_mempool.h b/lib/librte_mempool/rte_mempool.h index f81152af96..c08bb444ff 100644 --- a/lib/librte_mempool/rte_mempool.h +++ b/lib/librte_mempool/rte_mempool.h @@ -1108,7 +1108,10 @@ rte_mempool_free(struct rte_mempool *mp); * @return * The number of objects added on success. * On error, the chunk is not added in the memory list of the - * mempool and a negative errno is returned. + * mempool and a negative errno is returned: + * (-ENOBUFS): not enough room in chunk for one object. + * (-ENOSPC): mempool is already populated. + * (-ENOMEM): allocation failure. */ int rte_mempool_populate_iova(struct rte_mempool *mp, char *vaddr, rte_iova_t iova, size_t len, rte_mempool_memchunk_free_cb_t *free_cb, -- 2.39.5