From mboxrd@z Thu Jan 1 00:00:00 1970 From: Yang Hongyang Subject: Re: [PATCH 20/27] tools/libxl: Infrastructure for writing a v2 stream Date: Wed, 17 Jun 2015 09:31:21 +0800 Message-ID: <5580CDE9.7030800@cn.fujitsu.com> References: <1434375880-30914-1-git-send-email-andrew.cooper3@citrix.com> <1434375880-30914-21-git-send-email-andrew.cooper3@citrix.com> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii"; Format="flowed" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <1434375880-30914-21-git-send-email-andrew.cooper3@citrix.com> List-Unsubscribe: , List-Post: List-Help: List-Subscribe: , Sender: xen-devel-bounces@lists.xen.org Errors-To: xen-devel-bounces@lists.xen.org To: Andrew Cooper , Xen-devel Cc: Wei Liu , Ian Jackson , Ian Campbell , Ross Lagerwall List-Id: xen-devel@lists.xenproject.org On 06/15/2015 09:44 PM, Andrew Cooper wrote: [...] > + > +static void write_emulator_record(libxl__egc *egc, > + libxl__stream_write_state *stream) > +{ > + libxl__domain_suspend_state *dss = CONTAINER_OF(stream, *dss, sws); > + libxl__datacopier_state *dc = &stream->dc; > + STATE_AO_GC(stream->ao); > + struct libxl_sr_rec_hdr rec = { REC_TYPE_EMULATOR_CONTEXT, 0 }; > + struct libxl_sr_emulator_hdr ehdr = { 0 }; > + struct stat st; > + int ret = 0; > + uint32_t qemu_state_len; > + > + assert(dss->type == LIBXL_DOMAIN_TYPE_HVM); > + > + /* Convenience aliases */ > + const char *const filename = dss->dm_savefile; > + const uint32_t domid = dss->domid; > + > + switch(libxl__device_model_version_running(gc, domid)) { > + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN_TRADITIONAL: > + ehdr.id = EMULATOR_QEMU_TRADITIONAL; > + break; > + > + case LIBXL_DEVICE_MODEL_VERSION_QEMU_XEN: > + ehdr.id = EMULATOR_QEMU_UPSTREAM; > + break; > + > + default: > + ret = ERROR_FAIL; > + goto err; > + } > + > + ret = libxl__domain_suspend_device_model(gc, dss); This is no longer needed, the suspend callback already called this function and the emulator context already saved to a file. This call will cause Primary's emulator stop under Remus. postcopy callback will resume primary. then in checkpoint callback, we shouldn't suspend device model. > + if (ret) > + goto err; > + > + dc->readwhat = GCSPRINTF("qemu save file %s", filename); > + dc->copywhat = "emulator record"; > + dc->writewhat = "save/migration stream"; > + dc->callback = emulator_body_done; > + > + dc->readfd = open(filename, O_RDONLY); > + if (dc->readfd < 0) { > + LOGE(ERROR, "unable to open %s", dc->readwhat); > + goto err; > + } > + > + if (fstat(dc->readfd, &st)) > + { > + LOGE(ERROR, "unable to fstat %s", dc->readwhat); > + goto err; > + } > + > + if (!S_ISREG(st.st_mode)) { > + LOG(ERROR, "%s is not a plain file!", dc->readwhat); > + goto err; > + } > + > + qemu_state_len = st.st_size; > + rec.length = qemu_state_len + sizeof(ehdr); > + > + ret = libxl__datacopier_start(dc); > + if (ret) > + goto err; > + > + libxl__datacopier_prefixdata(egc, dc, &rec, sizeof(rec)); > + libxl__datacopier_prefixdata(egc, dc, &ehdr, sizeof(ehdr)); > + > + stream->padding = ROUNDUP(qemu_state_len, REC_ALIGN_ORDER) - qemu_state_len; > + return; > + > + err: > + assert(ret); > + stream_failed(egc, stream, ret); > +} > + > +static void emulator_body_done(libxl__egc *egc, > + libxl__datacopier_state *dc, > + int onwrite, int errnoval) > +{ > + libxl__stream_write_state *stream = CONTAINER_OF(dc, *stream, dc); > + STATE_AO_GC(stream->ao); > + int ret = 0; > + > + if (onwrite || errnoval) { > + ret = ERROR_FAIL; > + goto err; > + } > + > + dc->readwhat = ""; > + dc->readfd = -1; > + > + if (stream->padding) { > + assert(stream->padding < (1U << REC_ALIGN_ORDER)); > + > + dc->copywhat = "emulator padding"; > + dc->writewhat = "save/migration stream"; > + dc->callback = emulator_padding_done; > + > + ret = libxl__datacopier_start(dc); > + if (ret) > + goto err; > + > + libxl__datacopier_prefixdata(egc, dc, zero_padding, stream->padding); > + return; > + } > + > + emulator_padding_done(egc, dc, 0, 0); > + return; > + > + err: > + assert(ret); > + stream_failed(egc, stream, ret); > +} > + > +static void emulator_padding_done(libxl__egc *egc, > + libxl__datacopier_state *dc, > + int onwrite, int errnoval) > +{ > + libxl__stream_write_state *stream = CONTAINER_OF(dc, *stream, dc); > + STATE_AO_GC(stream->ao); > + int ret = 0; > + > + if (onwrite || errnoval) { > + ret = ERROR_FAIL; > + goto err; > + } > + > + write_end_record(egc, stream); > + return; > + > + err: > + assert(ret); > + stream_failed(egc, stream, ret); > +} > + > +static void write_end_record(libxl__egc *egc, > + libxl__stream_write_state *stream) > +{ > + libxl__datacopier_state *dc = &stream->dc; > + STATE_AO_GC(stream->ao); > + struct libxl_sr_rec_hdr rec = { REC_TYPE_END, 0 }; > + int ret = 0; > + > + dc->copywhat = "suspend footer"; > + dc->writewhat = "save/migration stream"; > + dc->callback = end_record_done; > + > + ret = libxl__datacopier_start(dc); > + if (ret) > + goto err; > + > + libxl__datacopier_prefixdata(egc, dc, &rec, sizeof(rec)); > + return; > + > + err: > + assert(ret); > + stream_failed(egc, stream, ret); > +} > + > +static void end_record_done(libxl__egc *egc, > + libxl__datacopier_state *dc, > + int onwrite, int errnoval) > +{ > + libxl__stream_write_state *stream = CONTAINER_OF(dc, *stream, dc); > + STATE_AO_GC(stream->ao); > + int ret = 0; > + > + if (onwrite || errnoval) { > + ret = ERROR_FAIL; > + goto err; > + } > + > + stream_success(egc, stream); > + return; > + > + err: > + assert(ret); > + stream_failed(egc, stream, ret); > +} > + > +/* > + * Local variables: > + * mode: C > + * c-basic-offset: 4 > + * indent-tabs-mode: nil > + * End: > + */ > -- Thanks, Yang.