From: Anatoly Burakov Date: Thu, 13 Dec 2018 11:43:16 +0000 (+0000) Subject: mem: check for memfd support in segment fd API X-Git-Url: http://git.droids-corp.org/?a=commitdiff_plain;h=d75eea314504834d18a94835ad858e3ecd0f8e41;p=dpdk.git mem: check for memfd support in segment fd API If memfd support was not compiled, or hugepage memfd support is not available at runtime, the API will now return proper error code, indicating that this API is unsupported. This changes the API, so document the changes. Fixes: 41dbdb68723b ("mem: add external API to retrieve page fd") Fixes: 3a44687139eb ("mem: allow querying offset into segment fd") Cc: stable@dpdk.org Signed-off-by: Anatoly Burakov Acked-by: Tiwei Bie Reviewed-by: Maxime Coquelin --- diff --git a/doc/guides/rel_notes/release_19_02.rst b/doc/guides/rel_notes/release_19_02.rst index 63e84fef78..010cac1d41 100644 --- a/doc/guides/rel_notes/release_19_02.rst +++ b/doc/guides/rel_notes/release_19_02.rst @@ -113,6 +113,8 @@ API Changes where segment fd API is not expected to be supported: - On attempt to get segment fd for an externally allocated memory segment + - In cases where memfd support would have been required to provide segment + fd's (such as in-memory or no-huge mode) * pdump: The ``rte_pdump_set_socket_dir()``, the parameter ``path`` of ``rte_pdump_init()`` and enum ``rte_pdump_socktype`` were deprecated diff --git a/lib/librte_eal/linuxapp/eal/eal_memalloc.c b/lib/librte_eal/linuxapp/eal/eal_memalloc.c index 7849395662..a93548b8c5 100644 --- a/lib/librte_eal/linuxapp/eal/eal_memalloc.c +++ b/lib/librte_eal/linuxapp/eal/eal_memalloc.c @@ -23,6 +23,10 @@ #include #include #include +#ifdef F_ADD_SEALS /* if file sealing is supported, so is memfd */ +#include +#define MEMFD_SUPPORTED +#endif #ifdef RTE_EAL_NUMA_AWARE_HUGEPAGES #include #include @@ -53,8 +57,8 @@ const int anonymous_hugepages_supported = #endif /* - * we don't actually care if memfd itself is supported - we only need to check - * if memfd supports hugetlbfs, as that already implies memfd support. + * we've already checked memfd support at compile-time, but we also need to + * check if we can create hugepage files with memfd. * * also, this is not a constant, because while we may be *compiled* with memfd * hugetlbfs support, we might not be *running* on a system that supports memfd @@ -63,10 +67,11 @@ const int anonymous_hugepages_supported = */ static int memfd_create_supported = #ifdef MFD_HUGETLB -#define MEMFD_SUPPORTED 1; +#define RTE_MFD_HUGETLB MFD_HUGETLB #else 0; +#define RTE_MFD_HUGETLB 4U #endif /* @@ -338,12 +343,12 @@ get_seg_memfd(struct hugepage_info *hi __rte_unused, int fd; char segname[250]; /* as per manpage, limit is 249 bytes plus null */ + int flags = RTE_MFD_HUGETLB | pagesz_flags(hi->hugepage_sz); + if (internal_config.single_file_segments) { fd = fd_list[list_idx].memseg_list_fd; if (fd < 0) { - int flags = MFD_HUGETLB | pagesz_flags(hi->hugepage_sz); - snprintf(segname, sizeof(segname), "seg_%i", list_idx); fd = memfd_create(segname, flags); if (fd < 0) { @@ -357,8 +362,6 @@ get_seg_memfd(struct hugepage_info *hi __rte_unused, fd = fd_list[list_idx].fds[seg_idx]; if (fd < 0) { - int flags = MFD_HUGETLB | pagesz_flags(hi->hugepage_sz); - snprintf(segname, sizeof(segname), "seg_%i-%i", list_idx, seg_idx); fd = memfd_create(segname, flags); @@ -1542,6 +1545,17 @@ int eal_memalloc_get_seg_fd(int list_idx, int seg_idx) { int fd; + + if (internal_config.in_memory || internal_config.no_hugetlbfs) { +#ifndef MEMFD_SUPPORTED + /* in in-memory or no-huge mode, we rely on memfd support */ + return -ENOTSUP; +#endif + /* memfd supported, but hugetlbfs memfd may not be */ + if (!internal_config.no_hugetlbfs && !memfd_create_supported) + return -ENOTSUP; + } + if (internal_config.single_file_segments) { fd = fd_list[list_idx].memseg_list_fd; } else if (fd_list[list_idx].len == 0) { @@ -1565,7 +1579,7 @@ test_memfd_create(void) int pagesz_flag = pagesz_flags(pagesz); int flags; - flags = pagesz_flag | MFD_HUGETLB; + flags = pagesz_flag | RTE_MFD_HUGETLB; int fd = memfd_create("test", flags); if (fd < 0) { /* we failed - let memalloc know this isn't working */ @@ -1589,6 +1603,16 @@ 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; + if (internal_config.in_memory || internal_config.no_hugetlbfs) { +#ifndef MEMFD_SUPPORTED + /* in in-memory or no-huge mode, we rely on memfd support */ + return -ENOTSUP; +#endif + /* memfd supported, but hugetlbfs memfd may not be */ + if (!internal_config.no_hugetlbfs && !memfd_create_supported) + return -ENOTSUP; + } + /* fd_list not initialized? */ if (fd_list[list_idx].len == 0) return -ENODEV;