From nobody Mon Feb 9 10:29:05 2026 Delivered-To: importer@patchew.org Authentication-Results: mx.zohomail.com; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org ARC-Seal: i=1; a=rsa-sha256; t=1560508761; cv=none; d=zoho.com; s=zohoarc; b=T6nVpLMhwFaJ/XllfkjI2fktAAkKEGkRd3gBmwz8grWUuVHNSebgLp+fx1IEg7uU3/yUP/2hv4FiTUZiI5g2g5P0YBB13MhXhMqyO8VPYVi1eSnsUw5oA79o/IHFrYVkCbeyRdm/igj2o/IyMBUcxIhkLuJNgr/GGUN/G1UgZlg= ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=zoho.com; s=zohoarc; t=1560508761; h=Content-Type:Content-Transfer-Encoding:Cc:Date:From:In-Reply-To:List-Subscribe:List-Post:List-Id:List-Help:List-Unsubscribe:MIME-Version:Message-ID:References:Sender:Subject:To:ARC-Authentication-Results; bh=rW62qzWa+k5Nl8LDshJJD/YmOLajQQ5Z2HYJmusr2tg=; b=DaqKHAIsAaZ2glOn0bc7XthzyBmcxPBelrVtVQciS8Ix8TvSVW4jmdXrj/+G88p5QTwBhCPWX37eBXmHI6meLpdrpOI+OD0rKHveD0sowHc1qqQXJFa3jHcAOE+Y9J8cGzjDbFDGAauK95j9jt9AsatozJEB7P2Lcw540zTUee0= ARC-Authentication-Results: i=1; mx.zoho.com; spf=none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) smtp.mailfrom=xen-devel-bounces@lists.xenproject.org Return-Path: Received: from lists.xenproject.org (lists.xenproject.org [192.237.175.120]) by mx.zohomail.com with SMTPS id 1560508761134732.8251846362455; Fri, 14 Jun 2019 03:39:21 -0700 (PDT) Received: from localhost ([127.0.0.1] helo=lists.xenproject.org) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hbjb5-0002mR-2D; Fri, 14 Jun 2019 10:38:15 +0000 Received: from all-amaz-eas1.inumbo.com ([34.197.232.57] helo=us1-amaz-eas2.inumbo.com) by lists.xenproject.org with esmtp (Exim 4.89) (envelope-from ) id 1hbjb3-0002la-DJ for xen-devel@lists.xenproject.org; Fri, 14 Jun 2019 10:38:13 +0000 Received: from esa5.hc3370-68.iphmx.com (unknown [216.71.155.168]) by us1-amaz-eas2.inumbo.com (Halon) with ESMTPS id 817943e4-8e90-11e9-a75c-0f081994aedc; Fri, 14 Jun 2019 10:38:11 +0000 (UTC) X-Inumbo-ID: 817943e4-8e90-11e9-a75c-0f081994aedc Authentication-Results: esa5.hc3370-68.iphmx.com; dkim=none (message not signed) header.i=none; spf=None smtp.pra=anthony.perard@citrix.com; spf=Pass smtp.mailfrom=anthony.perard@citrix.com; spf=None smtp.helo=postmaster@mail.citrix.com Received-SPF: none (zoho.com: 192.237.175.120 is neither permitted nor denied by domain of lists.xenproject.org) client-ip=192.237.175.120; envelope-from=xen-devel-bounces@lists.xenproject.org; helo=lists.xenproject.org; Received-SPF: None (esa5.hc3370-68.iphmx.com: no sender authenticity information available from domain of anthony.perard@citrix.com) identity=pra; client-ip=162.221.158.21; receiver=esa5.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible Received-SPF: Pass (esa5.hc3370-68.iphmx.com: domain of anthony.perard@citrix.com designates 162.221.158.21 as permitted sender) identity=mailfrom; client-ip=162.221.158.21; receiver=esa5.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="anthony.perard@citrix.com"; x-conformance=sidf_compatible; x-record-type="v=spf1"; x-record-text="v=spf1 ip4:209.167.231.154 ip4:178.63.86.133 ip4:195.66.111.40/30 ip4:85.115.9.32/28 ip4:199.102.83.4 ip4:192.28.146.160 ip4:192.28.146.107 ip4:216.52.6.88 ip4:216.52.6.188 ip4:162.221.158.21 ip4:162.221.156.83 ~all" Received-SPF: None (esa5.hc3370-68.iphmx.com: no sender authenticity information available from domain of postmaster@mail.citrix.com) identity=helo; client-ip=162.221.158.21; receiver=esa5.hc3370-68.iphmx.com; envelope-from="anthony.perard@citrix.com"; x-sender="postmaster@mail.citrix.com"; x-conformance=sidf_compatible IronPort-SDR: 0qVhVYaT2jvmX7RtBgudh/cq9gDSB3xQ8GnS8dWit037PN9fRcvBUU6+jE1bW7fhS93LScEAbE Ryq2VrO+zL01YJ02mbQ9OF7mDj1GqbY/wD+GvWmv404HoYz2x6hofEBm7TNCiRqeL+q9OhKVoH dSrHbTdpBWcwvrb4WFVYzvWUVzDmcC/bDsNlQ1G8GqUrvryEBkiPcxSC7MOiMwfQRnPB2ePNez 1OzVpcwNHfnNOYkEc1D7qNxfBdST4io7YEWPxvSIMH3vwPGerKL9Sm/o+BUMQWpySthK45Lyc+ Buw= X-SBRS: 2.7 X-MesageID: 1722753 X-Ironport-Server: esa5.hc3370-68.iphmx.com X-Remote-IP: 162.221.158.21 X-Policy: $RELAYED X-IronPort-AV: E=Sophos;i="5.63,373,1557201600"; d="scan'208";a="1722753" From: Anthony PERARD To: Date: Fri, 14 Jun 2019 11:37:58 +0100 Message-ID: <20190614103801.22619-7-anthony.perard@citrix.com> X-Mailer: git-send-email 2.22.0 In-Reply-To: <20190614103801.22619-1-anthony.perard@citrix.com> References: <20190614103801.22619-1-anthony.perard@citrix.com> MIME-Version: 1.0 Subject: [Xen-devel] [PATCH v2 6/9] libxl_disk: Cut libxl_cdrom_insert into steps .. X-BeenThere: xen-devel@lists.xenproject.org X-Mailman-Version: 2.1.23 Precedence: list List-Id: Xen developer discussion List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Cc: Anthony PERARD , Ian Jackson , Wei Liu Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: quoted-printable Errors-To: xen-devel-bounces@lists.xenproject.org Sender: "Xen-devel" .. and use a new "slow" lock to avoid holding the userdata lock across several functions. This patch cuts libxl_cdrom_insert into different step/function but there are still called synchronously. (Taking the ev_lock is the only step that might be asynchronous.) A later patch will call them asynchronously when QMP is involved. Thee userdata lock (json_lock) use to protect against concurrent change of cdrom is replaced by an ev_lock which can be held across different CTX_LOCK sections. The json_lock is still used when reading/modifying the domain userdata (mandatory) and update xenstore (mostly because it's updated as the same time as the userdata). Signed-off-by: Anthony PERARD Acked-by: Ian Jackson --- Notes: v2: - rewrite patch description - rework use of the new lock tools/libxl/libxl_disk.c | 196 +++++++++++++++++++++++++++++++-------- 1 file changed, 155 insertions(+), 41 deletions(-) diff --git a/tools/libxl/libxl_disk.c b/tools/libxl/libxl_disk.c index 45bf555061..5f13a622f9 100644 --- a/tools/libxl/libxl_disk.c +++ b/tools/libxl/libxl_disk.c @@ -642,24 +642,43 @@ int libxl_device_disk_getinfo(libxl_ctx *ctx, uint32_= t domid, return rc; } =20 +typedef struct { + libxl__ao *ao; + libxl_domid domid; + libxl_device_disk *disk; + libxl_device_disk disk_saved; + libxl__ev_lock qmp_lock; + int dm_ver; +} libxl__cdrom_insert_state; + +static void cdrom_insert_lock_acquired(libxl__egc *, libxl__ev_lock *, + int rc); +static void cdrom_insert_ejected(libxl__egc *egc, + libxl__cdrom_insert_state *cis); +static void cdrom_insert_inserted(libxl__egc *egc, + libxl__cdrom_insert_state *cis); +static void cdrom_insert_done(libxl__egc *egc, + libxl__cdrom_insert_state *cis, + int rc); + int libxl_cdrom_insert(libxl_ctx *ctx, uint32_t domid, libxl_device_disk *= disk, const libxl_asyncop_how *ao_how) { AO_CREATE(ctx, domid, ao_how); int num =3D 0, i; - libxl_device_disk *disks =3D NULL, disk_saved; - libxl_domain_config d_config; - int rc, dm_ver; - libxl__device device; - const char *be_path, *libxl_path; - char * tmp; - libxl__domain_userdata_lock *lock =3D NULL; - xs_transaction_t t =3D XBT_NULL; - flexarray_t *insert =3D NULL, *empty =3D NULL; - - libxl_domain_config_init(&d_config); - libxl_device_disk_init(&disk_saved); - libxl_device_disk_copy(ctx, &disk_saved, disk); + libxl_device_disk *disks =3D NULL; + int rc; + libxl__cdrom_insert_state *cis; + + GCNEW(cis); + cis->ao =3D ao; + cis->domid =3D domid; + cis->disk =3D disk; + libxl_device_disk_init(&cis->disk_saved); + libxl_device_disk_copy(ctx, &cis->disk_saved, disk); + libxl__ev_lock_init(&cis->qmp_lock); + cis->qmp_lock.ao =3D ao; + cis->qmp_lock.domid =3D domid; =20 libxl_domain_type type =3D libxl__domain_type(gc, domid); if (type =3D=3D LIBXL_DOMAIN_TYPE_INVALID) { @@ -678,8 +697,8 @@ int libxl_cdrom_insert(libxl_ctx *ctx, uint32_t domid, = libxl_device_disk *disk, goto out; } =20 - dm_ver =3D libxl__device_model_version_running(gc, domid); - if (dm_ver =3D=3D -1) { + cis->dm_ver =3D libxl__device_model_version_running(gc, domid); + if (cis->dm_ver =3D=3D -1) { LOGD(ERROR, domid, "Cannot determine device model version"); rc =3D ERROR_FAIL; goto out; @@ -708,40 +727,82 @@ int libxl_cdrom_insert(libxl_ctx *ctx, uint32_t domid= , libxl_device_disk *disk, disk->format =3D LIBXL_DISK_FORMAT_EMPTY; } =20 - rc =3D libxl__device_from_disk(gc, domid, disk, &device); - if (rc) goto out; +out: + libxl__device_list_free(&libxl__disk_devtype, disks, num); + if (rc) { + cdrom_insert_done(egc, cis, rc); /* must be last */ + } else { + cis->qmp_lock.callback =3D cdrom_insert_lock_acquired; + libxl__ev_lock_get(egc, &cis->qmp_lock); /* must be last */ + } + return AO_INPROGRESS; +} =20 - be_path =3D libxl__device_backend_path(gc, &device); - libxl_path =3D libxl__device_libxl_path(gc, &device); +static void cdrom_insert_lock_acquired(libxl__egc *egc, + libxl__ev_lock *lock, + int rc) +{ + libxl__cdrom_insert_state *cis =3D CONTAINER_OF(lock, *cis, qmp_lock); + STATE_AO_GC(cis->ao); =20 - /* Note: CTX lock is already held at this point so lock hierarchy - * is maintained. - */ - lock =3D libxl__lock_domain_userdata(gc, domid); - if (!lock) { - rc =3D ERROR_LOCK_FAIL; - goto out; - } + if (rc) goto out; =20 /* We need to eject the original image first. This is implemented * by inserting empty media. JSON is not updated. */ =20 - if (dm_ver =3D=3D LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { + if (cis->dm_ver =3D=3D LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { libxl_device_disk disk_empty; =20 libxl_device_disk_init(&disk_empty); disk_empty.format =3D LIBXL_DISK_FORMAT_EMPTY; - disk_empty.vdev =3D libxl__strdup(NOGC, disk->vdev); + disk_empty.vdev =3D libxl__strdup(NOGC, cis->disk->vdev); disk_empty.pdev_path =3D libxl__strdup(NOGC, ""); disk_empty.is_cdrom =3D 1; - libxl__device_disk_setdefault(gc, domid, &disk_empty, false); + libxl__device_disk_setdefault(gc, cis->domid, &disk_empty, false); =20 - rc =3D libxl__qmp_insert_cdrom(gc, domid, &disk_empty); + rc =3D libxl__qmp_insert_cdrom(gc, cis->domid, &disk_empty); libxl_device_disk_dispose(&disk_empty); if (rc) goto out; } =20 + cdrom_insert_ejected(egc, cis); /* must be last */ + return; + +out: + cdrom_insert_done(egc, cis, rc); /* must be last */ +} + +static void cdrom_insert_ejected(libxl__egc *egc, + libxl__cdrom_insert_state *cis) +{ + EGC_GC; + int rc; + libxl__domain_userdata_lock *data_lock =3D NULL; + libxl__device device; + const char *be_path, *libxl_path; + flexarray_t *empty =3D NULL; + xs_transaction_t t =3D XBT_NULL; + char *tmp; + libxl_domain_config d_config; + + /* convenience aliases */ + libxl_domid domid =3D cis->domid; + libxl_device_disk *disk =3D cis->disk; + + libxl_domain_config_init(&d_config); + + rc =3D libxl__device_from_disk(gc, domid, disk, &device); + if (rc) goto out; + be_path =3D libxl__device_backend_path(gc, &device); + libxl_path =3D libxl__device_libxl_path(gc, &device); + + data_lock =3D libxl__lock_domain_userdata(gc, domid); + if (!data_lock) { + rc =3D ERROR_LOCK_FAIL; + goto out; + } + empty =3D flexarray_make(gc, 4, 1); flexarray_append_pair(empty, "type", libxl__device_disk_string_of_backend(disk->backe= nd)); @@ -780,16 +841,66 @@ int libxl_cdrom_insert(libxl_ctx *ctx, uint32_t domid= , libxl_device_disk *disk, rc =3D libxl__get_domain_configuration(gc, domid, &d_config); if (rc) goto out; =20 - device_add_domain_config(gc, &d_config, &libxl__disk_devtype, &disk_sa= ved); + device_add_domain_config(gc, &d_config, &libxl__disk_devtype, + &cis->disk_saved); =20 rc =3D libxl__dm_check_start(gc, &d_config, domid); if (rc) goto out; =20 - if (dm_ver =3D=3D LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { + if (cis->dm_ver =3D=3D LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN) { rc =3D libxl__qmp_insert_cdrom(gc, domid, disk); if (rc) goto out; } =20 + rc =3D 0; + +out: + libxl__xs_transaction_abort(gc, &t); + libxl_domain_config_dispose(&d_config); + if (data_lock) libxl__unlock_domain_userdata(data_lock); + if (rc) { + cdrom_insert_done(egc, cis, rc); /* must be last */ + } else { + cdrom_insert_inserted(egc, cis); /* must be last */ + } +} + +static void cdrom_insert_inserted(libxl__egc *egc, + libxl__cdrom_insert_state *cis) +{ + EGC_GC; + int rc; + libxl__domain_userdata_lock *data_lock =3D NULL; + libxl_domain_config d_config; + flexarray_t *insert =3D NULL; + xs_transaction_t t =3D XBT_NULL; + libxl__device device; + const char *be_path, *libxl_path; + char *tmp; + + /* convenience aliases */ + libxl_domid domid =3D cis->domid; + libxl_device_disk *disk =3D cis->disk; + + libxl_domain_config_init(&d_config); + + rc =3D libxl__device_from_disk(gc, domid, disk, &device); + if (rc) goto out; + be_path =3D libxl__device_backend_path(gc, &device); + libxl_path =3D libxl__device_libxl_path(gc, &device); + + data_lock =3D libxl__lock_domain_userdata(gc, domid); + if (!data_lock) { + rc =3D ERROR_LOCK_FAIL; + goto out; + } + + rc =3D libxl__get_domain_configuration(gc, domid, &d_config); + if (rc) goto out; + + device_add_domain_config(gc, &d_config, &libxl__disk_devtype, + &cis->disk_saved); + insert =3D flexarray_make(gc, 4, 1); flexarray_append_pair(insert, "type", libxl__device_disk_string_of_backend(disk->backend)); @@ -830,21 +941,24 @@ int libxl_cdrom_insert(libxl_ctx *ctx, uint32_t domid= , libxl_device_disk *disk, if (rc < 0) goto out; } =20 - /* success, no actual async */ - libxl__ao_complete(egc, ao, 0); - rc =3D 0; =20 out: libxl__xs_transaction_abort(gc, &t); - libxl__device_list_free(&libxl__disk_devtype, disks, num); - libxl_device_disk_dispose(&disk_saved); libxl_domain_config_dispose(&d_config); + if (data_lock) libxl__unlock_domain_userdata(data_lock); + cdrom_insert_done(egc, cis, rc); /* must be last */ +} =20 - if (lock) libxl__unlock_domain_userdata(lock); +static void cdrom_insert_done(libxl__egc *egc, + libxl__cdrom_insert_state *cis, + int rc) +{ + EGC_GC; =20 - if (rc) return AO_CREATE_FAIL(rc); - return AO_INPROGRESS; + libxl__ev_unlock(gc, &cis->qmp_lock); + libxl_device_disk_dispose(&cis->disk_saved); + libxl__ao_complete(egc, cis->ao, rc); } =20 /* libxl__alloc_vdev only works on the local domain, that is the domain --=20 Anthony PERARD _______________________________________________ Xen-devel mailing list Xen-devel@lists.xenproject.org https://lists.xenproject.org/mailman/listinfo/xen-devel