From: Anatoly Burakov Date: Tue, 4 Sep 2018 15:15:49 +0000 (+0100) Subject: mem: allow querying offset into segment fd X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=3a44687139eb;p=dpdk.git mem: allow querying offset into segment fd In a few cases, user may need to query offset into fd for a particular memory segment (for example, to selectively map pages). This commit adds a new API to do that. Signed-off-by: Anatoly Burakov Reviewed-by: Maxime Coquelin --- diff --git a/lib/librte_eal/bsdapp/eal/eal_memalloc.c b/lib/librte_eal/bsdapp/eal/eal_memalloc.c index 80e4c3d4f3..06afbcc999 100644 --- a/lib/librte_eal/bsdapp/eal/eal_memalloc.c +++ b/lib/librte_eal/bsdapp/eal/eal_memalloc.c @@ -60,6 +60,12 @@ eal_memalloc_set_seg_fd(int list_idx, int seg_idx, int fd) return -ENOTSUP; } +int +eal_memalloc_get_seg_fd_offset(int list_idx, int seg_idx, size_t *offset) +{ + return -ENOTSUP; +} + int eal_memalloc_init(void) { diff --git a/lib/librte_eal/common/eal_common_memory.c b/lib/librte_eal/common/eal_common_memory.c index 4a80deaf52..0b69804ff8 100644 --- a/lib/librte_eal/common/eal_common_memory.c +++ b/lib/librte_eal/common/eal_common_memory.c @@ -599,6 +599,56 @@ rte_memseg_get_fd(const struct rte_memseg *ms) return ret; } +int __rte_experimental +rte_memseg_get_fd_offset_thread_unsafe(const struct rte_memseg *ms, + size_t *offset) +{ + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + struct rte_memseg_list *msl; + struct rte_fbarray *arr; + int msl_idx, seg_idx, ret; + + if (ms == NULL || offset == NULL) { + rte_errno = EINVAL; + return -1; + } + + msl = rte_mem_virt2memseg_list(ms->addr); + if (msl == NULL) { + rte_errno = EINVAL; + return -1; + } + arr = &msl->memseg_arr; + + msl_idx = msl - mcfg->memsegs; + seg_idx = rte_fbarray_find_idx(arr, ms); + + if (!rte_fbarray_is_used(arr, seg_idx)) { + rte_errno = ENOENT; + return -1; + } + + ret = eal_memalloc_get_seg_fd_offset(msl_idx, seg_idx, offset); + if (ret < 0) { + rte_errno = -ret; + ret = -1; + } + return ret; +} + +int __rte_experimental +rte_memseg_get_fd_offset(const struct rte_memseg *ms, size_t *offset) +{ + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + int ret; + + rte_rwlock_read_lock(&mcfg->memory_hotplug_lock); + ret = rte_memseg_get_fd_offset_thread_unsafe(ms, offset); + rte_rwlock_read_unlock(&mcfg->memory_hotplug_lock); + + return ret; +} + /* init memory subsystem */ int rte_eal_memory_init(void) diff --git a/lib/librte_eal/common/eal_memalloc.h b/lib/librte_eal/common/eal_memalloc.h index 70a214de4e..af917c2f9d 100644 --- a/lib/librte_eal/common/eal_memalloc.h +++ b/lib/librte_eal/common/eal_memalloc.h @@ -84,6 +84,9 @@ eal_memalloc_get_seg_fd(int list_idx, int seg_idx); int eal_memalloc_set_seg_fd(int list_idx, int seg_idx, int fd); +int +eal_memalloc_get_seg_fd_offset(int list_idx, int seg_idx, size_t *offset); + int eal_memalloc_init(void); diff --git a/lib/librte_eal/common/include/rte_memory.h b/lib/librte_eal/common/include/rte_memory.h index 0d2a30056e..14bd277a4d 100644 --- a/lib/librte_eal/common/include/rte_memory.h +++ b/lib/librte_eal/common/include/rte_memory.h @@ -365,6 +365,55 @@ rte_memseg_get_fd(const struct rte_memseg *ms); int __rte_experimental rte_memseg_get_fd_thread_unsafe(const struct rte_memseg *ms); +/** + * Get offset into segment file descriptor associated with a particular memseg + * (if available). + * + * @note This function read-locks the memory hotplug subsystem, and thus cannot + * be used within memory-related callback functions. + * + * @param ms + * A pointer to memseg for which to get file descriptor. + * @param offset + * A pointer to offset value where the result will be stored. + * + * @return + * Valid file descriptor in case of success. + * -1 in case of error, with ``rte_errno`` set to the following values: + * - EINVAL - ``ms`` pointer was NULL or did not point to a valid memseg + * - EINVAL - ``offset`` pointer was NULL + * - ENODEV - ``ms`` fd is not available + * - ENOENT - ``ms`` is an unused segment + * - ENOTSUP - segment fd's are not supported + */ +int __rte_experimental +rte_memseg_get_fd_offset(const struct rte_memseg *ms, size_t *offset); + +/** + * Get offset into segment file descriptor associated with a particular memseg + * (if available). + * + * @note This function does not perform any locking, and is only safe to call + * from within memory-related callback functions. + * + * @param ms + * A pointer to memseg for which to get file descriptor. + * @param offset + * A pointer to offset value where the result will be stored. + * + * @return + * Valid file descriptor in case of success. + * -1 in case of error, with ``rte_errno`` set to the following values: + * - EINVAL - ``ms`` pointer was NULL or did not point to a valid memseg + * - EINVAL - ``offset`` pointer was NULL + * - ENODEV - ``ms`` fd is not available + * - ENOENT - ``ms`` is an unused segment + * - ENOTSUP - segment fd's are not supported + */ +int __rte_experimental +rte_memseg_get_fd_offset_thread_unsafe(const struct rte_memseg *ms, + size_t *offset); + /** * Dump the physical memory layout to a file. * diff --git a/lib/librte_eal/linuxapp/eal/eal_memalloc.c b/lib/librte_eal/linuxapp/eal/eal_memalloc.c index 21f8427533..6fc9dc0ca7 100644 --- a/lib/librte_eal/linuxapp/eal/eal_memalloc.c +++ b/lib/librte_eal/linuxapp/eal/eal_memalloc.c @@ -1406,6 +1406,30 @@ eal_memalloc_get_seg_fd(int list_idx, int seg_idx) return fd; } +int +eal_memalloc_get_seg_fd_offset(int list_idx, int seg_idx, size_t *offset) +{ + struct rte_mem_config *mcfg = rte_eal_get_configuration()->mem_config; + + /* fd_list not initialized? */ + if (fd_list[list_idx].len == 0) + return -ENODEV; + if (internal_config.single_file_segments) { + size_t pgsz = mcfg->memsegs[list_idx].page_sz; + + /* segment not active? */ + if (fd_list[list_idx].memseg_list_fd < 0) + return -ENOENT; + *offset = pgsz * seg_idx; + } else { + /* segment not active? */ + if (fd_list[list_idx].fds[seg_idx] < 0) + return -ENOENT; + *offset = 0; + } + return 0; +} + int eal_memalloc_init(void) { diff --git a/lib/librte_eal/rte_eal_version.map b/lib/librte_eal/rte_eal_version.map index fb200dec5c..73282bbb06 100644 --- a/lib/librte_eal/rte_eal_version.map +++ b/lib/librte_eal/rte_eal_version.map @@ -328,7 +328,9 @@ EXPERIMENTAL { rte_memseg_contig_walk; rte_memseg_contig_walk_thread_unsafe; rte_memseg_get_fd; + rte_memseg_get_fd_offset; rte_memseg_get_fd_thread_unsafe; + rte_memseg_get_fd_offset_thread_unsafe; rte_memseg_list_walk; rte_memseg_list_walk_thread_unsafe; rte_memseg_walk;