raid6check: use O_DIRECT instead of O_SYNC.

O_DIRECT is more direct and is faster.
This requires aligned memory allocation, but that isn't hard.

Signed-off-by: NeilBrown <neilb@suse.de>

diff --git a/raid6check.c b/raid6check.c
index b2e173233ca6ef2853acb298661b27a4ff3d7f04..cb8522e523a6e26610878a9921ef8fc971df32a3 100644 (file)
--- a/raid6check.c
+++ b/raid6check.c
@@ -312,7 +312,7 @@ int check_stripes(struct mdinfo *info, int *source, unsigned long long *offsets,
        /* read the data and p and q blocks, and check we got them right */
        int data_disks = raid_disks - 2;
        int syndrome_disks = data_disks + is_ddf(layout) * 2;
-       char *stripe_buf = xmalloc(raid_disks * chunk_size);
+       char *stripe_buf;
 
        /* stripes[] is indexed by raid_disk and holds chunks from each device */
        char **stripes = xmalloc(raid_disks * sizeof(char*));
@@ -349,6 +349,7 @@ int check_stripes(struct mdinfo *info, int *source, unsigned long long *offsets,
        if (!tables_ready)
                make_tables();
 
+       posix_memalign((void**)&stripe_buf, 4096, raid_disks * chunk_size);
        block_index_for_slot += 2;
        blocks += 2;
        blocks_page += 2;
@@ -675,7 +676,7 @@ int main(int argc, char *argv[])
                if(disk_slot >= 0) {
                        disk_name[disk_slot] = map_dev(comp->disk.major, comp->disk.minor, 0);
                        offsets[disk_slot] = comp->data_offset * 512;
-                       fds[disk_slot] = open(disk_name[disk_slot], O_RDWR | O_SYNC);
+                       fds[disk_slot] = open(disk_name[disk_slot], O_RDWR | O_DIRECT);
                        if (fds[disk_slot] < 0) {
                                perror(disk_name[disk_slot]);
                                fprintf(stderr,"%s: cannot open %s\n", prg, disk_name[disk_slot]);