ibv_reg_mr() fails to register a memory region allocated on huge page and not the default page size. This happens because ibv_madvise_range() aligns memory region to the default system page size before calling to madvise() which fails with EINVAL error. madvise() fails because it expects that the start and end pointer of the memory range be huge page aligned. Patch handles the issue by: 1. ibv_fork_init() gets kernel's default huge page size in addition to the default page size. 2. ibv_madvise_range() first tries aligning users memory range to default page size and if madvise() fails with EINVAL error then it tries to align users memory range by huge page size and tries madvise() again.
Signed-off-by: Alex Vaynman <[email protected]> --- src/memory.c | 69 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++- 1 files changed, 68 insertions(+), 1 deletions(-) diff --git a/src/memory.c b/src/memory.c index 550015a..73db083 100644 --- a/src/memory.c +++ b/src/memory.c @@ -40,6 +40,9 @@ #include <unistd.h> #include <stdlib.h> #include <stdint.h> +#include <ctype.h> +#include <fcntl.h> +#include <string.h> #include "ibverbs.h" @@ -54,6 +57,8 @@ #define MADV_DOFORK 11 #endif +#define MEMINFO_SIZE 2048 + struct ibv_mem_node { enum { IBV_RED, @@ -68,8 +73,51 @@ struct ibv_mem_node { static struct ibv_mem_node *mm_root; static pthread_mutex_t mm_mutex = PTHREAD_MUTEX_INITIALIZER; static int page_size; +static int huge_page_size; static int too_late; +/* + * Get the kernel default huge page size. + */ +static int get_huge_page_size() +{ + int fd; + char buf[MEMINFO_SIZE]; + int mem_file_len; + char *p_hpage_val = NULL; + char *end_pointer = NULL; + char file_name[] = "/proc/meminfo"; + const char label[] = "Hugepagesize:"; + int ret_val = 0; + + fd = open(file_name, O_RDONLY); + if (fd < 0) + return fd; + + mem_file_len = read(fd, buf, sizeof(buf) - 1); + + close(fd); + if (mem_file_len < 0) + return mem_file_len; + + buf[mem_file_len] = '\0'; + + p_hpage_val = strstr(buf, label); + if (!p_hpage_val) { + errno = EINVAL; + return -1; + } + p_hpage_val += strlen(label); + + errno = 0; + ret_val = strtol(p_hpage_val, &end_pointer, 0); + + if (errno != 0) + return -1; + + return ret_val * 1024; +} + int ibv_fork_init(void) { void *tmp; @@ -85,6 +133,8 @@ int ibv_fork_init(void) if (page_size < 0) return errno; + huge_page_size = get_huge_page_size(); + if (posix_memalign(&tmp, page_size, page_size)) return ENOMEM; @@ -554,7 +604,8 @@ static struct ibv_mem_node *prepare_to_roll_back(struct ibv_mem_node *node, return node; } -static int ibv_madvise_range(void *base, size_t size, int advice) +static int ibv_madvise_range_helper(void *base, size_t size, int advice, + int page_size) { uintptr_t start, end; struct ibv_mem_node *node, *tmp; @@ -646,6 +697,22 @@ out: return ret; } +static int ibv_madvise_range(void *base, size_t size, int advice) +{ + int ret_val = 0; + + ret_val = ibv_madvise_range_helper(base, size, advice, page_size); + + /* + * if memory is backed by huge pages we need to align it + * to huge page boundary in order madvise() will succeed. + */ + if (ret_val == -1 && errno == EINVAL && huge_page_size > 0) + ret_val = ibv_madvise_range_helper(base, size, advice, huge_page_size); + + return ret_val; +} + int ibv_dontfork_range(void *base, size_t size) { if (mm_root) -- 1.5.5 -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
