Message ID | 1362992462-1864-1-git-send-email-morita.kazutaka@lab.ntt.co.jp |
---|---|
State | New |
Headers | show |
On Mon, Mar 11, 2013 at 06:01:02PM +0900, MORITA Kazutaka wrote: > If an io_flush handler is not set, qemu_aio_wait doesn't invoke > callbacks. > > Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp> > --- > block/sheepdog.c | 11 +++++++++-- > 1 file changed, 9 insertions(+), 2 deletions(-) > > diff --git a/block/sheepdog.c b/block/sheepdog.c > index e4ec32d..cb0eeed 100644 > --- a/block/sheepdog.c > +++ b/block/sheepdog.c > @@ -501,6 +501,13 @@ static void restart_co_req(void *opaque) > qemu_coroutine_enter(co, NULL); > } > > +static int have_co_req(void *opaque) > +{ > + /* this handler is set only when there is a pending request, so > + * always returns 1. */ > + return 1; > +} > + > typedef struct SheepdogReqCo { > int sockfd; > SheepdogReq *hdr; > @@ -523,14 +530,14 @@ static coroutine_fn void do_co_req(void *opaque) > unsigned int *rlen = srco->rlen; > > co = qemu_coroutine_self(); > - qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, NULL, co); > + qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, have_co_req, co); > > ret = send_co_req(sockfd, hdr, data, wlen); Which tree is this patch against? block/sheepdog.c:do_co_req() has a socket_set_block(sockfd) call before this line. Is there a guarantee that only one coroutine executes do_co_req() at a time? Otherwise the first coroutine that finishes the function sets io_flush to NULL even though there's still another request processing. Stefan
At Mon, 11 Mar 2013 15:39:05 +0100, Stefan Hajnoczi wrote: > > On Mon, Mar 11, 2013 at 06:01:02PM +0900, MORITA Kazutaka wrote: > > If an io_flush handler is not set, qemu_aio_wait doesn't invoke > > callbacks. > > > > Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp> > > --- > > block/sheepdog.c | 11 +++++++++-- > > 1 file changed, 9 insertions(+), 2 deletions(-) > > > > diff --git a/block/sheepdog.c b/block/sheepdog.c > > index e4ec32d..cb0eeed 100644 > > --- a/block/sheepdog.c > > +++ b/block/sheepdog.c > > @@ -501,6 +501,13 @@ static void restart_co_req(void *opaque) > > qemu_coroutine_enter(co, NULL); > > } > > > > +static int have_co_req(void *opaque) > > +{ > > + /* this handler is set only when there is a pending request, so > > + * always returns 1. */ > > + return 1; > > +} > > + > > typedef struct SheepdogReqCo { > > int sockfd; > > SheepdogReq *hdr; > > @@ -523,14 +530,14 @@ static coroutine_fn void do_co_req(void *opaque) > > unsigned int *rlen = srco->rlen; > > > > co = qemu_coroutine_self(); > > - qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, NULL, co); > > + qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, have_co_req, co); > > > > ret = send_co_req(sockfd, hdr, data, wlen); > > Which tree is this patch against? block/sheepdog.c:do_co_req() has a > socket_set_block(sockfd) call before this line. Sorry, I have another patch in my local tree that needed to be sent before this one. I'll send v2 including the missing patch. > > Is there a guarantee that only one coroutine executes do_co_req() at a > time? Otherwise the first coroutine that finishes the function sets > io_flush to NULL even though there's still another request processing. Yes - the sockfd is opened just before calling do_req() and is closed just after returning the function, so the sheepdog driver cannot call multiple do_co_req() at a time against the same socket descriptor. Thanks, Kazutaka
diff --git a/block/sheepdog.c b/block/sheepdog.c index e4ec32d..cb0eeed 100644 --- a/block/sheepdog.c +++ b/block/sheepdog.c @@ -501,6 +501,13 @@ static void restart_co_req(void *opaque) qemu_coroutine_enter(co, NULL); } +static int have_co_req(void *opaque) +{ + /* this handler is set only when there is a pending request, so + * always returns 1. */ + return 1; +} + typedef struct SheepdogReqCo { int sockfd; SheepdogReq *hdr; @@ -523,14 +530,14 @@ static coroutine_fn void do_co_req(void *opaque) unsigned int *rlen = srco->rlen; co = qemu_coroutine_self(); - qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, NULL, co); + qemu_aio_set_fd_handler(sockfd, NULL, restart_co_req, have_co_req, co); ret = send_co_req(sockfd, hdr, data, wlen); if (ret < 0) { goto out; } - qemu_aio_set_fd_handler(sockfd, restart_co_req, NULL, NULL, co); + qemu_aio_set_fd_handler(sockfd, restart_co_req, NULL, have_co_req, co); ret = qemu_co_recv(sockfd, hdr, sizeof(*hdr)); if (ret < sizeof(*hdr)) {
If an io_flush handler is not set, qemu_aio_wait doesn't invoke callbacks. Signed-off-by: MORITA Kazutaka <morita.kazutaka@lab.ntt.co.jp> --- block/sheepdog.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-)