From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ian Campbell Subject: Re: [PATCH 20/27] tools/libxl: Infrastructure for writing a v2 stream Date: Tue, 16 Jun 2015 15:57:06 +0100 Message-ID: <1434466626.13744.208.camel@citrix.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" 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 Cc: Ross Lagerwall , Wei Liu , Yang Hongyang , Ian Jackson , Xen-devel List-Id: xen-devel@lists.xenproject.org On Mon, 2015-06-15 at 14:44 +0100, Andrew Cooper wrote: > From: Ross Lagerwall > > Signed-off-by: Ross Lagerwall > Signed-off-by: Andrew Cooper > CC: Ian Campbell > CC: Ian Jackson > CC: Wei Liu > --- > tools/libxl/Makefile | 2 +- > tools/libxl/libxl_internal.h | 33 +++ > tools/libxl/libxl_stream_write.c | 536 ++++++++++++++++++++++++++++++++++++++ > 3 files changed, 570 insertions(+), 1 deletion(-) > create mode 100644 tools/libxl/libxl_stream_write.c > > diff --git a/tools/libxl/Makefile b/tools/libxl/Makefile > index ca0ae3e..63e32f7 100644 > --- a/tools/libxl/Makefile > +++ b/tools/libxl/Makefile > @@ -94,7 +94,7 @@ LIBXL_OBJS = flexarray.o libxl.o libxl_create.o libxl_dm.o libxl_pci.o \ > libxl_dom.o libxl_exec.o libxl_xshelp.o libxl_device.o \ > libxl_internal.o libxl_utils.o libxl_uuid.o \ > libxl_json.o libxl_aoutils.o libxl_numa.o libxl_vnuma.o \ > - libxl_stream_read.o \ > + libxl_stream_read.o libxl_stream_write.o \ > libxl_save_callout.o _libxl_save_msgs_callout.o \ > libxl_convert_callout.o \ > libxl_qmp.o libxl_event.o libxl_fork.o $(LIBXL_OBJS-y) > diff --git a/tools/libxl/libxl_internal.h b/tools/libxl/libxl_internal.h > index 5482950..82cd792 100644 > --- a/tools/libxl/libxl_internal.h > +++ b/tools/libxl/libxl_internal.h > @@ -2868,6 +2868,38 @@ typedef void libxl__domain_suspend_cb(libxl__egc*, > typedef void libxl__save_device_model_cb(libxl__egc*, > libxl__domain_suspend_state*, int rc); > > +/* State for writing a libxl migration v2 stream */ > +typedef struct libxl__stream_write_state libxl__stream_write_state; > + > +struct libxl__stream_write_state { > + /* filled by the user */ > + libxl__ao *ao; > + int fd; > + uint32_t domid; > + void (*completion_callback)(libxl__egc *egc, > + libxl__domain_suspend_state *dss, > + int rc); > + /* Private */ > + int rc; > + int joined_rc; > + size_t padding; > + bool running; > + libxl__datacopier_state dc; > +}; > + > +_hidden void libxl__stream_write_start(libxl__egc *egc, > + libxl__stream_write_state *stream); > + > +_hidden void libxl__stream_write_abort(libxl__egc *egc, > + libxl__stream_write_state *stream, > + int rc); > + > +static inline bool libxl__stream_write_inuse( > + const libxl__stream_write_state *stream) > +{ > + return stream->running; > +} > + > typedef struct libxl__logdirty_switch { > const char *cmd; > const char *cmd_path; > @@ -2907,6 +2939,7 @@ struct libxl__domain_suspend_state { > /* private for libxl__domain_save_device_model */ > libxl__save_device_model_cb *save_dm_callback; > libxl__datacopier_state save_dm_datacopier; > + libxl__stream_write_state sws; > }; > > > diff --git a/tools/libxl/libxl_stream_write.c b/tools/libxl/libxl_stream_write.c > new file mode 100644 > index 0000000..856d72e > --- /dev/null > +++ b/tools/libxl/libxl_stream_write.c > @@ -0,0 +1,536 @@ > +/* > + * Copyright (C) 2015 Citrix Ltd. > + * > + * This program is free software; you can redistribute it and/or modify > + * it under the terms of the GNU Lesser General Public License as published > + * by the Free Software Foundation; version 2.1 only. with the special > + * exception on linking described in file LICENSE. > + * > + * This program is distributed in the hope that it will be useful, > + * but WITHOUT ANY WARRANTY; without even the implied warranty of > + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the > + * GNU Lesser General Public License for more details. > + */ > + > +#include "libxl_osdeps.h" /* must come before any other headers */ > + > +#include "libxl_internal.h" > + > +/* > + * Infrastructure for writing a domain to a libxl migration v2 stream. > + * > + * Entry points from outside: > + * - libxl__stream_write_start() > + * - Start writing a stream from the start. > + * > + * In normal operation, there are two tasks running at once; this stream > + * processing, and the the libxl-save-helper. check_stream_finished() is used "the the". > + * to join all the tasks in both success and error cases. > + * > + * Nomenclature for event callbacks: > + * - $FOO_done(): Completion callback for $FOO > + * - write_$FOO(): Set up writing a $FOO Set up or actually write? > + > +void libxl__stream_write_start(libxl__egc *egc, > + libxl__stream_write_state *stream) > +{ > + libxl__datacopier_state *dc = &stream->dc; > + STATE_AO_GC(stream->ao); > + struct libxl_sr_hdr hdr = { 0 }; > + int ret = 0; > + > + assert(!stream->running); > + stream->running = true; > + > + memset(dc, 0, sizeof(*dc)); Please use the _init() > +static void check_stream_finished(libxl__egc *egc, > + libxl__domain_suspend_state *dss, > + int rc, const char *what) > +{ > + libxl__stream_write_state *stream = &dss->sws; > + STATE_AO_GC(dss->ao); > + > + LOG(INFO, "Task '%s' joining (rc %d)", what, rc); > + > + if (rc && !stream->joined_rc) { > + bool skip = false; > + /* First reported failure from joining tasks. Tear everything down */ > + stream->joined_rc = rc; This (not just this, but a bunch of the preceeding helpers) all looks rather familiar, can it be shared to some extent?