From patchwork Tue Nov 7 10:46:53 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Paul Durrant X-Patchwork-Id: 10046479 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id BAC076031B for ; Tue, 7 Nov 2017 11:17:05 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 9DE2B2913F for ; Tue, 7 Nov 2017 11:17:05 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 9226B29B11; Tue, 7 Nov 2017 11:17:05 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from lists.gnu.org (lists.gnu.org [208.118.235.17]) (using TLSv1 with cipher AES256-SHA (256/256 bits)) (No client certificate requested) by mail.wl.linuxfoundation.org (Postfix) with ESMTPS id E63A32913F for ; Tue, 7 Nov 2017 11:17:04 +0000 (UTC) Received: from localhost ([::1]:52716 helo=lists.gnu.org) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eC1sN-0006VS-Sp for patchwork-qemu-devel@patchwork.kernel.org; Tue, 07 Nov 2017 06:17:03 -0500 Received: from eggs.gnu.org ([2001:4830:134:3::10]:46116) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1eC1rk-0006VN-Gj for qemu-devel@nongnu.org; Tue, 07 Nov 2017 06:16:26 -0500 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1eC1rg-0004Ub-BX for qemu-devel@nongnu.org; Tue, 07 Nov 2017 06:16:24 -0500 Received: from smtp02.citrix.com ([66.165.176.63]:6410) by eggs.gnu.org with esmtps (TLS1.0:RSA_ARCFOUR_SHA1:16) (Exim 4.71) (envelope-from ) id 1eC1rg-0004TJ-2U for qemu-devel@nongnu.org; Tue, 07 Nov 2017 06:16:20 -0500 X-IronPort-AV: E=Sophos;i="5.44,358,1505779200"; d="scan'208";a="458261420" From: Paul Durrant To: , Date: Tue, 7 Nov 2017 05:46:53 -0500 Message-ID: <20171107104653.8913-1-paul.durrant@citrix.com> X-Mailer: git-send-email 2.11.0 MIME-Version: 1.0 X-detected-operating-system: by eggs.gnu.org: Genre and OS details not recognized. X-Received-From: 66.165.176.63 Subject: [Qemu-devel] [PATCH v3] xen-disk: use an IOThread per instance X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.21 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Anthony Perard , Kevin Wolf , Paul Durrant , Stefano Stabellini , Max Reitz Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" X-Virus-Scanned: ClamAV using ClamSMTP This patch allocates an IOThread object for each xen_disk instance and 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 Acked-by: Stefano Stabellini --- 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) "blk %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 = opaque; + struct XenBlkDev *blkdev = ioreq->blkdev; + + aio_context_acquire(blkdev->ctx); if (ret != 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 == BLKIF_OP_READ ? "read" : "write"); ioreq->aio_errors++; } @@ -607,10 +615,10 @@ static void qemu_aio_complete(void *opaque, int ret) if (ioreq->presync) { ioreq->presync = 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 == BLKIF_RSP_OKAY) { - block_acct_done(blk_get_stats(ioreq->blkdev->blk), &ioreq->acct); + block_acct_done(blk_get_stats(blkdev->blk), &ioreq->acct); } else { - block_acct_failed(blk_get_stats(ioreq->blkdev->blk), &ioreq->acct); + block_acct_failed(blk_get_stats(blkdev->blk), &ioreq->acct); } 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 = 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 = container_of(xendev, struct XenBlkDev, xendev); + Error *err = NULL; + + trace_xen_disk_alloc(xendev->name); QLIST_INIT(&blkdev->inflight); QLIST_INIT(&blkdev->finished); QLIST_INIT(&blkdev->freelist); - blkdev->bh = qemu_bh_new(blk_bh, blkdev); + + blkdev->iothread = iothread_create(xendev->name, &err); + assert(!err); + + blkdev->ctx = iothread_get_aio_context(blkdev->iothread); + blkdev->bh = aio_bh_new(blkdev->ctx, blk_bh, blkdev); + if (xen_mode != XEN_EMULATE) { batch_maps = 1; } @@ -950,6 +973,8 @@ static int blk_init(struct XenDevice *xendev) int info = 0; char *directiosafe = NULL; + trace_xen_disk_init(xendev->name); + /* read xenstore entries */ if (blkdev->params == NULL) { char *h = 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 = BDRV_O_NOCACHE | BDRV_O_NATIVE_AIO; @@ -1287,6 +1314,8 @@ static int blk_connect(struct XenDevice *xendev) blkdev->persistent_gnt_count = 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 = container_of(xendev, struct XenBlkDev, 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 = 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 = container_of(xendev, struct XenBlkDev, 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; }