seek_sanity_test: Report the actual allocation size

Instead of reporting the preferred block size for I/O as returned by
stat(2) as the allocation size, report the actual allocation size.
Clean things up a little in the process.

Signed-off-by: Andreas Gruenbacher <agruenba@redhat.com>
Reviewed-by: Eryu Guan <eguan@redhat.com>
Signed-off-by: Eryu Guan <eguan@redhat.com>

diff --git a/src/seek_sanity_test.c b/src/seek_sanity_test.c
index 064a8fa5822ff6bffcab1c048bed800e4682244a..c9e9366adbd90c5365c322e27250d7ae6f9b7704 100644 (file)
--- a/src/seek_sanity_test.c
+++ b/src/seek_sanity_test.c
@@ -51,19 +51,51 @@ static void get_file_system(int fd)
 
 static int get_io_sizes(int fd)
 {
-       struct stat buf;
-       int ret;
+       off_t pos = 0, offset = 1;
+       struct stat buf;
+       int shift, ret;
 
-       ret = fstat(fd, &buf);
-       if (ret)
-               fprintf(stderr, "  ERROR %d: Failed to find io blocksize\n",
-                       errno);
+       ret = fstat(fd, &buf);
+       if (ret) {
+               fprintf(stderr, "  ERROR %d: Failed to find io blocksize\n",
+                       errno);
+               return ret;
+       }
 
-       /* st_blksize is typically also the allocation size */
-       alloc_size = buf.st_blksize;
-       fprintf(stdout, "Allocation size: %ld\n", alloc_size);
+       /* st_blksize is typically also the allocation size */
+       alloc_size = buf.st_blksize;
 
-       return ret;
+       /* try to discover the actual alloc size */
+       while (pos == 0 && offset < alloc_size) {
+               offset <<= 1;
+               ftruncate(fd, 0);
+               pwrite(fd, "a", 1, offset);
+               pos = lseek(fd, 0, SEEK_DATA);
+               if (pos == -1)
+                       goto fail;
+       }
+
+       /* bisect */
+       shift = offset >> 2;
+       while (shift && offset < alloc_size) {
+               ftruncate(fd, 0);
+               pwrite(fd, "a", 1, offset);
+               pos = lseek(fd, 0, SEEK_DATA);
+               if (pos == -1)
+                       goto fail;
+               offset += pos ? -shift : shift;
+               shift >>= 1;
+       }
+       if (!shift)
+               offset += pos ? 0 : 1;
+       alloc_size = offset;
+       fprintf(stdout, "Allocation size: %ld\n", alloc_size);
+       return 0;
+
+fail:
+       fprintf(stderr, "Kernel does not support llseek(2) extension "
+               "SEEK_DATA. Aborting.\n");
+       return -1;
 }
 
 #define do_free(x)     do { if(x) free(x); } while(0);
@@ -902,8 +934,8 @@ static int run_test(struct testrec *tr)
 
 static int test_basic_support(void)
 {
-       int ret = -1, fd, shift;
-       off_t pos = 0, offset = 1;
+       int ret = -1, fd;
+       off_t pos;
        char *buf = NULL;
        int bufsz, filsz;
 
@@ -917,34 +949,6 @@ static int test_basic_support(void)
        if (ret)
                goto out;
 
-       /* try to discover the actual alloc size */
-       while (pos == 0 && offset < alloc_size) {
-               offset <<= 1;
-               ftruncate(fd, 0);
-               pwrite(fd, "a", 1, offset);
-               pos = lseek(fd, 0, SEEK_DATA);
-       }
-
-       /* bisect */
-       shift = offset >> 2;
-       while (shift && offset < alloc_size) {
-               ftruncate(fd, 0);
-               pwrite(fd, "a", 1, offset);
-               pos = lseek(fd, 0, SEEK_DATA);
-               offset += pos ? -shift : shift;
-               shift >>= 1;
-       }
-       if (!shift)
-               offset += pos ? 0 : 1;
-       alloc_size = offset;
-
-       if (pos == -1) {
-               fprintf(stderr, "Kernel does not support llseek(2) extension "
-                       "SEEK_DATA. Aborting.\n");
-               ret = -1;
-               goto out;
-       }
-
        ftruncate(fd, 0);
        bufsz = alloc_size * 2;
        filsz = bufsz * 2;