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| author | Sami Kerola | 2014-07-16 22:54:57 +0200 |
|---|---|---|
| committer | Karel Zak | 2014-07-17 14:01:00 +0200 |
| commit | 0407c1bef9f5bc39da0fcf2e21bc5bd8b48b5349 (patch) | |
| tree | bea5d6d977f5d3885699185b998d83e6c4de0c43 /sys-utils/fallocate.c | |
| parent | lib/colors: remove memory leak (diff) | |
| download | kernel-qcow2-util-linux-0407c1bef9f5bc39da0fcf2e21bc5bd8b48b5349.tar.gz kernel-qcow2-util-linux-0407c1bef9f5bc39da0fcf2e21bc5bd8b48b5349.tar.xz kernel-qcow2-util-linux-0407c1bef9f5bc39da0fcf2e21bc5bd8b48b5349.zip | |
fallocate: avoid unnecessary computation
Where POSIX_FADV_SEQUENTIAL and HAVE_POSIX_FADVISE are not available it
is waste of resources to have variables that are meaningful only for
posix_fadvise(). Also initialize the variables immediately to correct
values, and since cachesz is never changed mark it read only.
Signed-off-by: Sami Kerola <kerolasa@iki.fi>
Diffstat (limited to 'sys-utils/fallocate.c')
| -rw-r--r-- | sys-utils/fallocate.c | 21 |
1 files changed, 10 insertions, 11 deletions
diff --git a/sys-utils/fallocate.c b/sys-utils/fallocate.c index 93fd3b48e..c619f64cc 100644 --- a/sys-utils/fallocate.c +++ b/sys-utils/fallocate.c @@ -174,17 +174,12 @@ static void dig_holes(int fd, off_t off, off_t len) { off_t end = len ? off + len : 0; off_t hole_start = 0, hole_sz = 0; - off_t cache_start = 0; uintmax_t ct = 0; - size_t bufsz, cachesz; + size_t bufsz; char *buf; struct stat st; - - if (fstat(fd, &st) != 0) - err(EXIT_FAILURE, _("stat failed %s"), filename); - - bufsz = st.st_blksize; - +#if defined(POSIX_FADV_SEQUENTIAL) && defined(HAVE_POSIX_FADVISE) + off_t cache_start = off; /* * We don't want to call POSIX_FADV_DONTNEED to discard cached * data in PAGE_SIZE steps. IMHO it's overkill (too many syscalls). @@ -193,15 +188,19 @@ static void dig_holes(int fd, off_t off, off_t len) * a good compromise. * -- kzak Feb-2014 */ - cachesz = getpagesize() * 256; + const size_t cachesz = getpagesize() * 256; +#endif + + if (fstat(fd, &st) != 0) + err(EXIT_FAILURE, _("stat failed %s"), filename); + + bufsz = st.st_blksize; if (lseek(fd, off, SEEK_SET) < 0) err(EXIT_FAILURE, _("seek on %s failed"), filename); /* buffer + extra space for is_nul() sentinel */ buf = xmalloc(bufsz + sizeof(uintptr_t)); - cache_start = off; - #if defined(POSIX_FADV_SEQUENTIAL) && defined(HAVE_POSIX_FADVISE) posix_fadvise(fd, off, 0, POSIX_FADV_SEQUENTIAL); #endif |