From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from eggs.gnu.org ([2001:4830:134:3::10]:36859) by lists.gnu.org with esmtp (Exim 4.71) (envelope-from ) id 1ddDwv-0001SK-61 for qemu-devel@nongnu.org; Thu, 03 Aug 2017 07:05:54 -0400 Received: from Debian-exim by eggs.gnu.org with spam-scanned (Exim 4.71) (envelope-from ) id 1ddDwq-0004fn-Nz for qemu-devel@nongnu.org; Thu, 03 Aug 2017 07:05:53 -0400 Received: from mx1.redhat.com ([209.132.183.28]:15388) by eggs.gnu.org with esmtps (TLS1.0:DHE_RSA_AES_256_CBC_SHA1:32) (Exim 4.71) (envelope-from ) id 1ddDwq-0004en-9P for qemu-devel@nongnu.org; Thu, 03 Aug 2017 07:05:48 -0400 Date: Thu, 3 Aug 2017 12:05:41 +0100 From: "Dr. David Alan Gilbert" Message-ID: <20170803110540.GE2076@work-vm> References: <1501229198-30588-1-git-send-email-peterx@redhat.com> <1501229198-30588-24-git-send-email-peterx@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <1501229198-30588-24-git-send-email-peterx@redhat.com> Subject: Re: [Qemu-devel] [RFC 23/29] migration: new cmd MIG_CMD_POSTCOPY_RESUME List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: Peter Xu Cc: qemu-devel@nongnu.org, Laurent Vivier , Alexey Perevalov , Juan Quintela , Andrea Arcangeli * Peter Xu (peterx@redhat.com) wrote: > Introducing this new command to be sent when the source VM is ready to > resume the paused migration. What the destination does here is > basically release the fault thread to continue service page faults. > > Signed-off-by: Peter Xu > --- > migration/savevm.c | 27 +++++++++++++++++++++++++++ > migration/savevm.h | 1 + > migration/trace-events | 1 + > 3 files changed, 29 insertions(+) > > diff --git a/migration/savevm.c b/migration/savevm.c > index def9213..2e330bc 100644 > --- a/migration/savevm.c > +++ b/migration/savevm.c > @@ -77,6 +77,7 @@ enum qemu_vm_cmd { > MIG_CMD_POSTCOPY_RAM_DISCARD, /* A list of pages to discard that > were previously sent during > precopy but are dirty. */ > + MIG_CMD_POSTCOPY_RESUME, /* resume postcopy on dest */ > MIG_CMD_PACKAGED, /* Send a wrapped stream within this stream */ > MIG_CMD_RECV_BITMAP, /* Request for recved bitmap on dst */ > MIG_CMD_MAX > @@ -95,6 +96,7 @@ static struct mig_cmd_args { > [MIG_CMD_POSTCOPY_RUN] = { .len = 0, .name = "POSTCOPY_RUN" }, > [MIG_CMD_POSTCOPY_RAM_DISCARD] = { > .len = -1, .name = "POSTCOPY_RAM_DISCARD" }, > + [MIG_CMD_POSTCOPY_RESUME] = { .len = 0, .name = "POSTCOPY_RESUME" }, > [MIG_CMD_PACKAGED] = { .len = 4, .name = "PACKAGED" }, > [MIG_CMD_RECV_BITMAP] = { .len = -1, .name = "RECV_BITMAP" }, > [MIG_CMD_MAX] = { .len = -1, .name = "MAX" }, > @@ -931,6 +933,12 @@ void qemu_savevm_send_postcopy_run(QEMUFile *f) > qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RUN, 0, NULL); > } > > +void qemu_savevm_send_postcopy_resume(QEMUFile *f) > +{ > + trace_savevm_send_postcopy_resume(); > + qemu_savevm_command_send(f, MIG_CMD_POSTCOPY_RESUME, 0, NULL); > +} > + > void qemu_savevm_send_recv_bitmap(QEMUFile *f, char *block_name) > { > size_t len; > @@ -1671,6 +1679,22 @@ static int loadvm_postcopy_handle_run(MigrationIncomingState *mis) > return LOADVM_QUIT; > } > > +static int loadvm_postcopy_handle_resume(MigrationIncomingState *mis) > +{ > + /* > + * This means source VM is ready to resume the postcopy migration. > + * It's time to switch state and release the fault thread to > + * continue service page faults. > + */ > + migrate_set_state(&mis->state, MIGRATION_STATUS_POSTCOPY_RECOVER, > + MIGRATION_STATUS_POSTCOPY_ACTIVE); > + qemu_sem_post(&mis->postcopy_pause_sem_fault); Is it worth sanity checking that you were in RECOVER at this point? Dave > + > + /* TODO: Tell source that "we are ready" */ > + > + return 0; > +} > + > /** > * Immediately following this command is a blob of data containing an embedded > * chunk of migration stream; read it and load it. > @@ -1834,6 +1858,9 @@ static int loadvm_process_command(QEMUFile *f) > case MIG_CMD_POSTCOPY_RAM_DISCARD: > return loadvm_postcopy_ram_handle_discard(mis, len); > > + case MIG_CMD_POSTCOPY_RESUME: > + return loadvm_postcopy_handle_resume(mis); > + > case MIG_CMD_RECV_BITMAP: > return loadvm_handle_recv_bitmap(mis, len); > } > diff --git a/migration/savevm.h b/migration/savevm.h > index 8126b1c..a5f3879 100644 > --- a/migration/savevm.h > +++ b/migration/savevm.h > @@ -46,6 +46,7 @@ int qemu_savevm_send_packaged(QEMUFile *f, const uint8_t *buf, size_t len); > void qemu_savevm_send_postcopy_advise(QEMUFile *f); > void qemu_savevm_send_postcopy_listen(QEMUFile *f); > void qemu_savevm_send_postcopy_run(QEMUFile *f); > +void qemu_savevm_send_postcopy_resume(QEMUFile *f); > void qemu_savevm_send_recv_bitmap(QEMUFile *f, char *block_name); > > void qemu_savevm_send_postcopy_ram_discard(QEMUFile *f, const char *name, > diff --git a/migration/trace-events b/migration/trace-events > index ed69551..04dd9d8 100644 > --- a/migration/trace-events > +++ b/migration/trace-events > @@ -34,6 +34,7 @@ savevm_send_open_return_path(void) "" > savevm_send_ping(uint32_t val) "%x" > savevm_send_postcopy_listen(void) "" > savevm_send_postcopy_run(void) "" > +savevm_send_postcopy_resume(void) "" > savevm_send_recv_bitmap(char *name) "%s" > savevm_state_setup(void) "" > savevm_state_header(void) "" > -- > 2.7.4 > -- Dr. David Alan Gilbert / dgilbert@redhat.com / Manchester, UK