From 6864a7b5aced6d8d9b287b92db8d7a996ea2e8a3 Mon Sep 17 00:00:00 2001 From: "Dr. David Alan Gilbert" Date: Mon, 12 Mar 2018 17:21:06 +0000 Subject: vhost+postcopy: Transmit 'listen' to slave MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Notify the vhost-user slave on reception of the 'postcopy-listen' event from the source. Signed-off-by: Dr. David Alan Gilbert Reviewed-by: Marc-André Lureau Reviewed-by: Peter Xu Reviewed-by: Michael S. Tsirkin Signed-off-by: Michael S. Tsirkin --- contrib/libvhost-user/libvhost-user.c | 19 +++++++++++++++++++ contrib/libvhost-user/libvhost-user.h | 2 ++ docs/interop/vhost-user.txt | 11 +++++++++++ hw/virtio/trace-events | 3 +++ hw/virtio/vhost-user.c | 34 ++++++++++++++++++++++++++++++++++ migration/postcopy-ram.h | 1 + migration/savevm.c | 7 +++++++ 7 files changed, 77 insertions(+) diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index 9e31f47b7a..e53b1953df 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -98,6 +98,7 @@ vu_request_to_string(unsigned int req) REQ(VHOST_USER_GET_CONFIG), REQ(VHOST_USER_SET_CONFIG), REQ(VHOST_USER_POSTCOPY_ADVISE), + REQ(VHOST_USER_POSTCOPY_LISTEN), REQ(VHOST_USER_MAX), }; #undef REQ @@ -931,6 +932,22 @@ out: return true; /* = send a reply */ } +static bool +vu_set_postcopy_listen(VuDev *dev, VhostUserMsg *vmsg) +{ + vmsg->payload.u64 = -1; + vmsg->size = sizeof(vmsg->payload.u64); + + if (dev->nregions) { + vu_panic(dev, "Regions already registered at postcopy-listen"); + return true; + } + dev->postcopy_listening = true; + + vmsg->flags = VHOST_USER_VERSION | VHOST_USER_REPLY_MASK; + vmsg->payload.u64 = 0; /* Success */ + return true; +} static bool vu_process_message(VuDev *dev, VhostUserMsg *vmsg) { @@ -1004,6 +1021,8 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg) break; case VHOST_USER_POSTCOPY_ADVISE: return vu_set_postcopy_advise(dev, vmsg); + case VHOST_USER_POSTCOPY_LISTEN: + return vu_set_postcopy_listen(dev, vmsg); default: vmsg_close_fds(vmsg); vu_panic(dev, "Unhandled request: %d", vmsg->request); diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h index 074b7860f6..ed505cf0c1 100644 --- a/contrib/libvhost-user/libvhost-user.h +++ b/contrib/libvhost-user/libvhost-user.h @@ -86,6 +86,7 @@ typedef enum VhostUserRequest { VHOST_USER_CREATE_CRYPTO_SESSION = 26, VHOST_USER_CLOSE_CRYPTO_SESSION = 27, VHOST_USER_POSTCOPY_ADVISE = 28, + VHOST_USER_POSTCOPY_LISTEN = 29, VHOST_USER_MAX } VhostUserRequest; @@ -285,6 +286,7 @@ struct VuDev { /* Postcopy data */ int postcopy_ufd; + bool postcopy_listening; }; typedef struct VuVirtqElement { diff --git a/docs/interop/vhost-user.txt b/docs/interop/vhost-user.txt index 7854e50008..0d24203d31 100644 --- a/docs/interop/vhost-user.txt +++ b/docs/interop/vhost-user.txt @@ -709,6 +709,17 @@ Master message types the slave must open a userfaultfd for later use. Note that at this stage the migration is still in precopy mode. + * VHOST_USER_POSTCOPY_LISTEN + Id: 29 + Master payload: N/A + + Master advises slave that a transition to postcopy mode has happened. + The slave must ensure that shared memory is registered with userfaultfd + to cause faulting of non-present pages. + + This is always sent sometime after a VHOST_USER_POSTCOPY_ADVISE, and + thus only when VHOST_USER_PROTOCOL_F_PAGEFAULT is supported. + Slave message types ------------------- diff --git a/hw/virtio/trace-events b/hw/virtio/trace-events index 742ff0f90b..06ec03d6e7 100644 --- a/hw/virtio/trace-events +++ b/hw/virtio/trace-events @@ -6,6 +6,9 @@ vhost_region_add_section(const char *name, uint64_t gpa, uint64_t size, uint64_t vhost_region_add_section_abut(const char *name, uint64_t new_size) "%s: 0x%"PRIx64 vhost_section(const char *name, int r) "%s:%d" +# hw/virtio/vhost-user.c +vhost_user_postcopy_listen(void) "" + # hw/virtio/virtio.c virtqueue_alloc_element(void *elem, size_t sz, unsigned in_num, unsigned out_num) "elem %p size %zd in_num %u out_num %u" virtqueue_fill(void *vq, const void *elem, unsigned int len, unsigned int idx) "vq %p elem %p len %u idx %u" diff --git a/hw/virtio/vhost-user.c b/hw/virtio/vhost-user.c index 5900583437..c3ab2994fb 100644 --- a/hw/virtio/vhost-user.c +++ b/hw/virtio/vhost-user.c @@ -20,6 +20,7 @@ #include "sysemu/cryptodev.h" #include "migration/migration.h" #include "migration/postcopy-ram.h" +#include "trace.h" #include #include @@ -79,6 +80,7 @@ typedef enum VhostUserRequest { VHOST_USER_CREATE_CRYPTO_SESSION = 26, VHOST_USER_CLOSE_CRYPTO_SESSION = 27, VHOST_USER_POSTCOPY_ADVISE = 28, + VHOST_USER_POSTCOPY_LISTEN = 29, VHOST_USER_MAX } VhostUserRequest; @@ -172,6 +174,8 @@ struct vhost_user { int slave_fd; NotifierWithReturn postcopy_notifier; struct PostCopyFD postcopy_fd; + /* True once we've entered postcopy_listen */ + bool postcopy_listen; }; static bool ioeventfd_enabled(void) @@ -858,6 +862,33 @@ static int vhost_user_postcopy_advise(struct vhost_dev *dev, Error **errp) return 0; } +/* + * Called at the switch to postcopy on reception of the 'listen' command. + */ +static int vhost_user_postcopy_listen(struct vhost_dev *dev, Error **errp) +{ + struct vhost_user *u = dev->opaque; + int ret; + VhostUserMsg msg = { + .hdr.request = VHOST_USER_POSTCOPY_LISTEN, + .hdr.flags = VHOST_USER_VERSION | VHOST_USER_NEED_REPLY_MASK, + }; + u->postcopy_listen = true; + trace_vhost_user_postcopy_listen(); + if (vhost_user_write(dev, &msg, NULL, 0) < 0) { + error_setg(errp, "Failed to send postcopy_listen to vhost"); + return -1; + } + + ret = process_message_reply(dev, &msg); + if (ret) { + error_setg(errp, "Failed to receive reply to postcopy_listen"); + return ret; + } + + return 0; +} + static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier, void *opaque) { @@ -880,6 +911,9 @@ static int vhost_user_postcopy_notifier(NotifierWithReturn *notifier, case POSTCOPY_NOTIFY_INBOUND_ADVISE: return vhost_user_postcopy_advise(dev, pnd->errp); + case POSTCOPY_NOTIFY_INBOUND_LISTEN: + return vhost_user_postcopy_listen(dev, pnd->errp); + default: /* We ignore notifications we don't know */ break; diff --git a/migration/postcopy-ram.h b/migration/postcopy-ram.h index f21eef6702..c8ced3470b 100644 --- a/migration/postcopy-ram.h +++ b/migration/postcopy-ram.h @@ -131,6 +131,7 @@ void postcopy_infrastructure_init(void); enum PostcopyNotifyReason { POSTCOPY_NOTIFY_PROBE = 0, POSTCOPY_NOTIFY_INBOUND_ADVISE, + POSTCOPY_NOTIFY_INBOUND_LISTEN, }; struct PostcopyNotifyData { diff --git a/migration/savevm.c b/migration/savevm.c index 1f2bf12a28..305c3ceaf5 100644 --- a/migration/savevm.c +++ b/migration/savevm.c @@ -1618,6 +1618,8 @@ static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis) { PostcopyState ps = postcopy_state_set(POSTCOPY_INCOMING_LISTENING); trace_loadvm_postcopy_handle_listen(); + Error *local_err = NULL; + if (ps != POSTCOPY_INCOMING_ADVISE && ps != POSTCOPY_INCOMING_DISCARD) { error_report("CMD_POSTCOPY_LISTEN in wrong postcopy state (%d)", ps); return -1; @@ -1643,6 +1645,11 @@ static int loadvm_postcopy_handle_listen(MigrationIncomingState *mis) } } + if (postcopy_notify(POSTCOPY_NOTIFY_INBOUND_LISTEN, &local_err)) { + error_report_err(local_err); + return -1; + } + if (mis->have_listen_thread) { error_report("CMD_POSTCOPY_RAM_LISTEN already has a listen thread"); return -1; -- cgit v1.2.1