summaryrefslogtreecommitdiffstats
path: root/xlators/storage/posix/src/posix-aio.c
diff options
context:
space:
mode:
authorAnand Avati <avati@redhat.com>2012-09-30 13:26:59 -0700
committerAnand Avati <avati@redhat.com>2012-10-01 16:39:09 -0700
commit5f9ad8a2bcc18d8ae828140d20203de496b371a4 (patch)
tree368d2dab4f1d1ca45d9ffbed4b425bb47859cb4b /xlators/storage/posix/src/posix-aio.c
parent5b896df0543e484b4de4de0a6ffa1053c5f92273 (diff)
linux-aio: fixes while setting O_DIRECT flag
Linux AIO needs O_DIRECT to be set for effective operation. O_DIRECT in turn has constraints on when it can work (offset, size alignment) So use O_DIRECT (unless instructed by application) only when offset and size alignments match. Else, io_submit() will happen over non-O_DIRECT fd, effectively blocking till the completion of the IO. Also fix a multithreading bug where detection/setting of O_DIRECT for a request was not atomic with io_submit() of that request. Change-Id: I190017e8bc78217429aff0714dca224cbe6f251d BUG: 837495 Signed-off-by: Anand Avati <avati@redhat.com> Reviewed-on: http://review.gluster.org/4006 Tested-by: Gluster Build System <jenkins@build.gluster.com> Reviewed-by: Amar Tumballi <amarts@redhat.com> Tested-by: Amar Tumballi <amarts@redhat.com>
Diffstat (limited to 'xlators/storage/posix/src/posix-aio.c')
-rw-r--r--xlators/storage/posix/src/posix-aio.c64
1 files changed, 60 insertions, 4 deletions
diff --git a/xlators/storage/posix/src/posix-aio.c b/xlators/storage/posix/src/posix-aio.c
index c520f44..0a776b9 100644
--- a/xlators/storage/posix/src/posix-aio.c
+++ b/xlators/storage/posix/src/posix-aio.c
@@ -21,6 +21,47 @@
#include <libaio.h>
+void
+__posix_fd_set_odirect (fd_t *fd, struct posix_fd *pfd, int opflags,
+ off_t offset, size_t size)
+{
+ int odirect = 0;
+ int flags = 0;
+ int ret = 0;
+
+ odirect = pfd->odirect;
+
+ if ((fd->flags|opflags) & O_DIRECT) {
+ /* if instructed, use O_DIRECT always */
+ odirect = 1;
+ } else {
+ /* else use O_DIRECT when feasible */
+ if ((offset|size) & 0xfff)
+ odirect = 0;
+ else
+ odirect = 1;
+ }
+
+ if (!odirect && pfd->odirect) {
+ flags = fcntl (pfd->fd, F_GETFL);
+ ret = fcntl (pfd->fd, F_SETFL, (flags & (~O_DIRECT)));
+ pfd->odirect = 0;
+ }
+
+ if (odirect && !pfd->odirect) {
+ flags = fcntl (pfd->fd, F_GETFL);
+ ret = fcntl (pfd->fd, F_SETFL, (flags | O_DIRECT));
+ pfd->odirect = 1;
+ }
+
+ if (ret) {
+ gf_log (THIS->name, GF_LOG_WARNING,
+ "fcntl() failed (%s). fd=%d flags=%d pfd->odirect=%d",
+ strerror (errno), pfd->fd, flags, pfd->odirect);
+ }
+}
+
+
struct posix_aio_cb {
struct iocb iocb;
call_frame_t *frame;
@@ -142,7 +183,7 @@ posix_aio_readv (call_frame_t *frame, xlator_t *this, fd_t *fd,
priv = this->private;
- ret = posix_fd_ctx_get_off (fd, this, &pfd, offset);
+ ret = posix_fd_ctx_get (fd, this, &pfd);
if (ret < 0) {
op_errno = -ret;
gf_log (this->name, GF_LOG_WARNING,
@@ -186,7 +227,14 @@ posix_aio_readv (call_frame_t *frame, xlator_t *this, fd_t *fd,
iocb = &paiocb->iocb;
- ret = io_submit (priv->ctxp, 1, &iocb);
+ LOCK (&fd->lock);
+ {
+ __posix_fd_set_odirect (fd, pfd, flags, offset, size);
+
+ ret = io_submit (priv->ctxp, 1, &iocb);
+ }
+ UNLOCK (&fd->lock);
+
if (ret != 1) {
gf_log (this->name, GF_LOG_ERROR,
"io_submit() returned %d", ret);
@@ -292,7 +340,7 @@ posix_aio_writev (call_frame_t *frame, xlator_t *this, fd_t *fd,
priv = this->private;
- ret = posix_fd_ctx_get_off (fd, this, &pfd, offset);
+ ret = posix_fd_ctx_get (fd, this, &pfd);
if (ret < 0) {
op_errno = -ret;
gf_log (this->name, GF_LOG_WARNING,
@@ -334,7 +382,15 @@ posix_aio_writev (call_frame_t *frame, xlator_t *this, fd_t *fd,
}
- ret = io_submit (priv->ctxp, 1, &iocb);
+ LOCK (&fd->lock);
+ {
+ __posix_fd_set_odirect (fd, pfd, flags, offset,
+ iov_length (iov, count));
+
+ ret = io_submit (priv->ctxp, 1, &iocb);
+ }
+ UNLOCK (&fd->lock);
+
if (ret != 1) {
gf_log (this->name, GF_LOG_ERROR,
"io_submit() returned %d", ret);