From 55cc1b5937a8e709e4c102e74b206281073aab82 Mon Sep 17 00:00:00 2001 From: Lidong Chen Date: Mon, 6 Aug 2018 21:29:28 +0800 Subject: [PATCH] migration: create a dedicated connection for rdma return path If start a RDMA migration with postcopy enabled, the source qemu establish a dedicated connection for return path. Signed-off-by: Lidong Chen Reviewed-by: Dr. David Alan Gilbert Reviewed-by: Juan Quintela Signed-off-by: Juan Quintela --- migration/rdma.c | 94 ++++++++++++++++++++++++++++++++++++++++++++++-- 1 file changed, 91 insertions(+), 3 deletions(-) diff --git a/migration/rdma.c b/migration/rdma.c index 76424a5e38..57af5ed392 100644 --- a/migration/rdma.c +++ b/migration/rdma.c @@ -387,6 +387,10 @@ typedef struct RDMAContext { uint64_t unregistrations[RDMA_SIGNALED_SEND_MAX]; GHashTable *blockmap; + + /* the RDMAContext for return path */ + struct RDMAContext *return_path; + bool is_return_path; } RDMAContext; #define TYPE_QIO_CHANNEL_RDMA "qio-channel-rdma" @@ -2323,10 +2327,22 @@ static void qemu_rdma_cleanup(RDMAContext *rdma) rdma_destroy_id(rdma->cm_id); rdma->cm_id = NULL; } + + /* the destination side, listen_id and channel is shared */ if (rdma->listen_id) { - rdma_destroy_id(rdma->listen_id); + if (!rdma->is_return_path) { + rdma_destroy_id(rdma->listen_id); + } rdma->listen_id = NULL; + + if (rdma->channel) { + if (!rdma->is_return_path) { + rdma_destroy_event_channel(rdma->channel); + } + rdma->channel = NULL; + } } + if (rdma->channel) { rdma_destroy_event_channel(rdma->channel); rdma->channel = NULL; @@ -2555,6 +2571,25 @@ err_dest_init_create_listen_id: } +static void qemu_rdma_return_path_dest_init(RDMAContext *rdma_return_path, + RDMAContext *rdma) +{ + int idx; + + for (idx = 0; idx < RDMA_WRID_MAX; idx++) { + rdma_return_path->wr_data[idx].control_len = 0; + rdma_return_path->wr_data[idx].control_curr = NULL; + } + + /*the CM channel and CM id is shared*/ + rdma_return_path->channel = rdma->channel; + rdma_return_path->listen_id = rdma->listen_id; + + rdma->return_path = rdma_return_path; + rdma_return_path->return_path = rdma; + rdma_return_path->is_return_path = true; +} + static void *qemu_rdma_data_init(const char *host_port, Error **errp) { RDMAContext *rdma = NULL; @@ -3012,6 +3047,8 @@ err: return ret; } +static void rdma_accept_incoming_migration(void *opaque); + static int qemu_rdma_accept(RDMAContext *rdma) { RDMACapabilities cap; @@ -3106,7 +3143,14 @@ static int qemu_rdma_accept(RDMAContext *rdma) } } - qemu_set_fd_handler(rdma->channel->fd, NULL, NULL, NULL); + /* Accept the second connection request for return path */ + if (migrate_postcopy() && !rdma->is_return_path) { + qemu_set_fd_handler(rdma->channel->fd, rdma_accept_incoming_migration, + NULL, + (void *)(intptr_t)rdma->return_path); + } else { + qemu_set_fd_handler(rdma->channel->fd, NULL, NULL, NULL); + } ret = rdma_accept(rdma->cm_id, &conn_param); if (ret) { @@ -3691,6 +3735,10 @@ static void rdma_accept_incoming_migration(void *opaque) trace_qemu_rdma_accept_incoming_migration_accepted(); + if (rdma->is_return_path) { + return; + } + f = qemu_fopen_rdma(rdma, "rb"); if (f == NULL) { ERROR(errp, "could not qemu_fopen_rdma!"); @@ -3705,7 +3753,7 @@ static void rdma_accept_incoming_migration(void *opaque) void rdma_start_incoming_migration(const char *host_port, Error **errp) { int ret; - RDMAContext *rdma; + RDMAContext *rdma, *rdma_return_path; Error *local_err = NULL; trace_rdma_start_incoming_migration(); @@ -3732,12 +3780,24 @@ void rdma_start_incoming_migration(const char *host_port, Error **errp) trace_rdma_start_incoming_migration_after_rdma_listen(); + /* initialize the RDMAContext for return path */ + if (migrate_postcopy()) { + rdma_return_path = qemu_rdma_data_init(host_port, &local_err); + + if (rdma_return_path == NULL) { + goto err; + } + + qemu_rdma_return_path_dest_init(rdma_return_path, rdma); + } + qemu_set_fd_handler(rdma->channel->fd, rdma_accept_incoming_migration, NULL, (void *)(intptr_t)rdma); return; err: error_propagate(errp, local_err); g_free(rdma); + g_free(rdma_return_path); } void rdma_start_outgoing_migration(void *opaque, @@ -3745,6 +3805,7 @@ void rdma_start_outgoing_migration(void *opaque, { MigrationState *s = opaque; RDMAContext *rdma = qemu_rdma_data_init(host_port, errp); + RDMAContext *rdma_return_path = NULL; int ret = 0; if (rdma == NULL) { @@ -3765,6 +3826,32 @@ void rdma_start_outgoing_migration(void *opaque, goto err; } + /* RDMA postcopy need a seprate queue pair for return path */ + if (migrate_postcopy()) { + rdma_return_path = qemu_rdma_data_init(host_port, errp); + + if (rdma_return_path == NULL) { + goto err; + } + + ret = qemu_rdma_source_init(rdma_return_path, + s->enabled_capabilities[MIGRATION_CAPABILITY_RDMA_PIN_ALL], errp); + + if (ret) { + goto err; + } + + ret = qemu_rdma_connect(rdma_return_path, errp); + + if (ret) { + goto err; + } + + rdma->return_path = rdma_return_path; + rdma_return_path->return_path = rdma; + rdma_return_path->is_return_path = true; + } + trace_rdma_start_outgoing_migration_after_rdma_connect(); s->to_dst_file = qemu_fopen_rdma(rdma, "wb"); @@ -3772,4 +3859,5 @@ void rdma_start_outgoing_migration(void *opaque, return; err: g_free(rdma); + g_free(rdma_return_path); }