From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:57568) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eFGj3-0000dY-SG for qemu-devel@nongnu.org; Thu, 16 Nov 2017 04:44:51 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eFGj0-0007sp-Ko for qemu-devel@nongnu.org; Thu, 16 Nov 2017 04:44:49 -0500 Received: from smtp.eu.citrix.com ([185.25.65.24]:47864) by eggs.gnu.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.71) (envelope-from ) id 1eFGj0-0007nU-6z for qemu-devel@nongnu.org; Thu, 16 Nov 2017 04:44:46 -0500 From: Paul Durrant Date: Thu, 16 Nov 2017 09:44:41 +0000 Message-ID: References: <20171107104653.8913-1-paul.durrant@citrix.com> <88c9ab0549a8456e8305353134e099ca@AMSPEX02CL03.citrite.net> In-Reply-To: Content-Language: en-US Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: quoted-printable MIME-Version: 1.0 Subject: Re: [Qemu-devel] [PATCH v3] xen-disk: use an IOThread per instance List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: 'Stefano Stabellini' Cc: "qemu-devel@nongnu.org" , "xen-devel@lists.xenproject.org" , Anthony Perard , Kevin Wolf , Max Reitz > -----Original Message----- > From: Stefano Stabellini [mailto:sstabellini@kernel.org] > Sent: 16 November 2017 01:11 > To: Paul Durrant > Cc: qemu-devel@nongnu.org; xen-devel@lists.xenproject.org; Stefano > Stabellini ; Anthony Perard > ; Kevin Wolf ; Max Reitz > > Subject: RE: [PATCH v3] xen-disk: use an IOThread per instance >=20 > On Wed, 15 Nov 2017, Paul Durrant wrote: > > Anthony, Stefano, > > > > Ping? >=20 > Acked-by: Stefano Stabellini >=20 > Unless Anthony or somebody else object, I'll queue it up in my "next" > branch (which I'll send upstream after 2.11 is out). Great. Thanks, Paul >=20 > Cheers, >=20 > Stefano >=20 >=20 > > > -----Original Message----- > > > From: Paul Durrant [mailto:paul.durrant@citrix.com] > > > Sent: 07 November 2017 10:47 > > > To: qemu-devel@nongnu.org; xen-devel@lists.xenproject.org > > > Cc: Paul Durrant ; Stefano Stabellini > > > ; Anthony Perard ; > > > Kevin Wolf ; Max Reitz > > > Subject: [PATCH v3] xen-disk: use an IOThread per instance > > > > > > This patch allocates an IOThread object for each xen_disk instance an= d > > > sets the AIO context appropriately on connect. This allows processing > > > of I/O to proceed in parallel. > > > > > > The patch also adds tracepoints into xen_disk to make it possible to > > > follow the state transtions of an instance in the log. > > > > > > Signed-off-by: Paul Durrant > > > --- > > > Cc: Stefano Stabellini > > > Cc: Anthony Perard > > > Cc: Kevin Wolf > > > Cc: Max Reitz > > > > > > v3: > > > - Use new iothread_create/destroy() functions > > > > > > v2: > > > - explicitly acquire and release AIO context in qemu_aio_complete() = and > > > blk_bh() > > > --- > > > hw/block/trace-events | 7 +++++++ > > > hw/block/xen_disk.c | 53 > > > ++++++++++++++++++++++++++++++++++++++++++++------- > > > 2 files changed, 53 insertions(+), 7 deletions(-) > > > > > > diff --git a/hw/block/trace-events b/hw/block/trace-events > > > index cb6767b3ee..962a3bfa24 100644 > > > --- a/hw/block/trace-events > > > +++ b/hw/block/trace-events > > > @@ -10,3 +10,10 @@ virtio_blk_submit_multireq(void *vdev, void *mrb, > int > > > start, int num_reqs, uint6 > > > # hw/block/hd-geometry.c > > > hd_geometry_lchs_guess(void *blk, int cyls, int heads, int secs) "bl= k %p > > > LCHS %d %d %d" > > > hd_geometry_guess(void *blk, uint32_t cyls, uint32_t heads, uint32_t > secs, > > > int trans) "blk %p CHS %u %u %u trans %d" > > > + > > > +# hw/block/xen_disk.c > > > +xen_disk_alloc(char *name) "%s" > > > +xen_disk_init(char *name) "%s" > > > +xen_disk_connect(char *name) "%s" > > > +xen_disk_disconnect(char *name) "%s" > > > +xen_disk_free(char *name) "%s" > > > diff --git a/hw/block/xen_disk.c b/hw/block/xen_disk.c > > > index e431bd89e8..f74fcd42d1 100644 > > > --- a/hw/block/xen_disk.c > > > +++ b/hw/block/xen_disk.c > > > @@ -27,10 +27,12 @@ > > > #include "hw/xen/xen_backend.h" > > > #include "xen_blkif.h" > > > #include "sysemu/blockdev.h" > > > +#include "sysemu/iothread.h" > > > #include "sysemu/block-backend.h" > > > #include "qapi/error.h" > > > #include "qapi/qmp/qdict.h" > > > #include "qapi/qmp/qstring.h" > > > +#include "trace.h" > > > > > > /* ------------------------------------------------------------- */ > > > > > > @@ -125,6 +127,9 @@ struct XenBlkDev { > > > DriveInfo *dinfo; > > > BlockBackend *blk; > > > QEMUBH *bh; > > > + > > > + IOThread *iothread; > > > + AioContext *ctx; > > > }; > > > > > > /* ------------------------------------------------------------- */ > > > @@ -596,9 +601,12 @@ static int ioreq_runio_qemu_aio(struct ioreq > > > *ioreq); > > > static void qemu_aio_complete(void *opaque, int ret) > > > { > > > struct ioreq *ioreq =3D opaque; > > > + struct XenBlkDev *blkdev =3D ioreq->blkdev; > > > + > > > + aio_context_acquire(blkdev->ctx); > > > > > > if (ret !=3D 0) { > > > - xen_pv_printf(&ioreq->blkdev->xendev, 0, "%s I/O error\n", > > > + xen_pv_printf(&blkdev->xendev, 0, "%s I/O error\n", > > > ioreq->req.operation =3D=3D BLKIF_OP_READ ? "r= ead" : "write"); > > > ioreq->aio_errors++; > > > } > > > @@ -607,10 +615,10 @@ static void qemu_aio_complete(void *opaque, > int > > > ret) > > > if (ioreq->presync) { > > > ioreq->presync =3D 0; > > > ioreq_runio_qemu_aio(ioreq); > > > - return; > > > + goto done; > > > } > > > if (ioreq->aio_inflight > 0) { > > > - return; > > > + goto done; > > > } > > > > > > if (xen_feature_grant_copy) { > > > @@ -647,16 +655,19 @@ static void qemu_aio_complete(void *opaque, > int > > > ret) > > > } > > > case BLKIF_OP_READ: > > > if (ioreq->status =3D=3D BLKIF_RSP_OKAY) { > > > - block_acct_done(blk_get_stats(ioreq->blkdev->blk), &iore= q- > >acct); > > > + block_acct_done(blk_get_stats(blkdev->blk), &ioreq->acct= ); > > > } else { > > > - block_acct_failed(blk_get_stats(ioreq->blkdev->blk), &io= req- > >acct); > > > + block_acct_failed(blk_get_stats(blkdev->blk), &ioreq->ac= ct); > > > } > > > break; > > > case BLKIF_OP_DISCARD: > > > default: > > > break; > > > } > > > - qemu_bh_schedule(ioreq->blkdev->bh); > > > + qemu_bh_schedule(blkdev->bh); > > > + > > > +done: > > > + aio_context_release(blkdev->ctx); > > > } > > > > > > static bool blk_split_discard(struct ioreq *ioreq, blkif_sector_t > > > sector_number, > > > @@ -913,17 +924,29 @@ static void blk_handle_requests(struct > XenBlkDev > > > *blkdev) > > > static void blk_bh(void *opaque) > > > { > > > struct XenBlkDev *blkdev =3D opaque; > > > + > > > + aio_context_acquire(blkdev->ctx); > > > blk_handle_requests(blkdev); > > > + aio_context_release(blkdev->ctx); > > > } > > > > > > static void blk_alloc(struct XenDevice *xendev) > > > { > > > struct XenBlkDev *blkdev =3D container_of(xendev, struct XenBlkD= ev, > > > xendev); > > > + Error *err =3D NULL; > > > + > > > + trace_xen_disk_alloc(xendev->name); > > > > > > QLIST_INIT(&blkdev->inflight); > > > QLIST_INIT(&blkdev->finished); > > > QLIST_INIT(&blkdev->freelist); > > > - blkdev->bh =3D qemu_bh_new(blk_bh, blkdev); > > > + > > > + blkdev->iothread =3D iothread_create(xendev->name, &err); > > > + assert(!err); > > > + > > > + blkdev->ctx =3D iothread_get_aio_context(blkdev->iothread); > > > + blkdev->bh =3D aio_bh_new(blkdev->ctx, blk_bh, blkdev); > > > + > > > if (xen_mode !=3D XEN_EMULATE) { > > > batch_maps =3D 1; > > > } > > > @@ -950,6 +973,8 @@ static int blk_init(struct XenDevice *xendev) > > > int info =3D 0; > > > char *directiosafe =3D NULL; > > > > > > + trace_xen_disk_init(xendev->name); > > > + > > > /* read xenstore entries */ > > > if (blkdev->params =3D=3D NULL) { > > > char *h =3D NULL; > > > @@ -1062,6 +1087,8 @@ static int blk_connect(struct XenDevice > *xendev) > > > unsigned int i; > > > uint32_t *domids; > > > > > > + trace_xen_disk_connect(xendev->name); > > > + > > > /* read-only ? */ > > > if (blkdev->directiosafe) { > > > qflags =3D BDRV_O_NOCACHE | BDRV_O_NATIVE_AIO; > > > @@ -1287,6 +1314,8 @@ static int blk_connect(struct XenDevice > *xendev) > > > blkdev->persistent_gnt_count =3D 0; > > > } > > > > > > + blk_set_aio_context(blkdev->blk, blkdev->ctx); > > > + > > > xen_be_bind_evtchn(&blkdev->xendev); > > > > > > xen_pv_printf(&blkdev->xendev, 1, "ok: proto %s, nr-ring-ref %u,= " > > > @@ -1300,13 +1329,20 @@ static void blk_disconnect(struct XenDevice > > > *xendev) > > > { > > > struct XenBlkDev *blkdev =3D container_of(xendev, struct XenBlkD= ev, > > > xendev); > > > > > > + trace_xen_disk_disconnect(xendev->name); > > > + > > > + aio_context_acquire(blkdev->ctx); > > > + > > > if (blkdev->blk) { > > > + blk_set_aio_context(blkdev->blk, qemu_get_aio_context()); > > > blk_detach_dev(blkdev->blk, blkdev); > > > blk_unref(blkdev->blk); > > > blkdev->blk =3D NULL; > > > } > > > xen_pv_unbind_evtchn(&blkdev->xendev); > > > > > > + aio_context_release(blkdev->ctx); > > > + > > > if (blkdev->sring) { > > > xengnttab_unmap(blkdev->xendev.gnttabdev, blkdev->sring, > > > blkdev->nr_ring_ref); > > > @@ -1345,6 +1381,8 @@ static int blk_free(struct XenDevice *xendev) > > > struct XenBlkDev *blkdev =3D container_of(xendev, struct XenBlkD= ev, > > > xendev); > > > struct ioreq *ioreq; > > > > > > + trace_xen_disk_free(xendev->name); > > > + > > > blk_disconnect(xendev); > > > > > > while (!QLIST_EMPTY(&blkdev->freelist)) { > > > @@ -1360,6 +1398,7 @@ static int blk_free(struct XenDevice *xendev) > > > g_free(blkdev->dev); > > > g_free(blkdev->devtype); > > > qemu_bh_delete(blkdev->bh); > > > + iothread_destroy(blkdev->iothread); > > > return 0; > > > } > > > > > > -- > > > 2.11.0 > >