[v2,for-4.0,4/7] libvhost-user: Support recording inflight I/O in shared memory

Message ID	20181218100002.11219-5-xieyongji@baidu.com (mailing list archive)
State	New, archived
Headers	show Return-Path: <qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org> From: elohimes@gmail.com To: mst@redhat.com, marcandre.lureau@redhat.com, jasowang@redhat.com, yury-kotov@yandex-team.ru, maxime.coquelin@redhat.com Date: Tue, 18 Dec 2018 17:59:59 +0800 Message-Id: <20181218100002.11219-5-xieyongji@baidu.com> In-Reply-To: <20181218100002.11219-1-xieyongji@baidu.com> References: <20181218100002.11219-1-xieyongji@baidu.com> Subject: [Qemu-devel] [PATCH v2 for-4.0 4/7] libvhost-user: Support recording inflight I/O in shared memory Precedence: list Cc: nixun@baidu.com, qemu-devel@nongnu.org, lilin24@baidu.com, zhangyu31@baidu.com, chaiwen@baidu.com, Xie Yongji <xieyongji@baidu.com> Errors-To: qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org Sender: "Qemu-devel" <qemu-devel-bounces+patchwork-qemu-devel=patchwork.kernel.org@nongnu.org>
Series	vhost-user-blk: Add support for backend reconnecting \| expand [v2,for-4.0,0/7] vhost-user-blk: Add support for backend reconnecting [v2,for-4.0,1/7] chardev: Add disconnected option for chardev socket [v2,for-4.0,2/7] vhost-user: Support providing shared memory to backend [v2,for-4.0,3/7] libvhost-user: Introduce vu_queue_map_desc() [v2,for-4.0,4/7] libvhost-user: Support recording inflight I/O in shared memory [v2,for-4.0,5/7] vhost-user-blk: Add support to provide shared memory to backend [v2,for-4.0,6/7] vhost-user-blk: Add support to reconnect backend [v2,for-4.0,7/7] contrib/vhost-user-blk: enable inflight I/O recording

diff --git a/contrib/libvhost-user/libvhost-user.c b/contrib/libvhost-user/libvhost-user.c index 23bd52264c..f18f5e6e62 100644 --- a/contrib/libvhost-user/libvhost-user.c +++ b/contrib/libvhost-user/libvhost-user.c @@ -53,6 +53,18 @@ _min1 < _min2 ? _min1 : _min2; }) #endif +/* Round number down to multiple */ +#define ALIGN_DOWN(n, m) ((n) / (m) * (m)) + +/* Round number up to multiple */ +#define ALIGN_UP(n, m) ALIGN_DOWN((n) + (m) - 1, (m)) + +/* Align each region to cache line size in shared memory */ +#define SHM_ALIGNMENT 64 + +/* The version of shared memory */ +#define SHM_VERSION 1 + #define VHOST_USER_HDR_SIZE offsetof(VhostUserMsg, payload.u64) /* The version of the protocol we support */ @@ -100,6 +112,8 @@ vu_request_to_string(unsigned int req) REQ(VHOST_USER_POSTCOPY_ADVISE), REQ(VHOST_USER_POSTCOPY_LISTEN), REQ(VHOST_USER_POSTCOPY_END), + REQ(VHOST_USER_GET_SHM_SIZE), + REQ(VHOST_USER_SET_SHM_FD), REQ(VHOST_USER_MAX), }; #undef REQ @@ -890,6 +904,41 @@ vu_check_queue_msg_file(VuDev *dev, VhostUserMsg *vmsg) return true; } +static int +vu_check_queue_inflights(VuDev *dev, VuVirtq *vq) +{ + int i = 0; + + if ((dev->protocol_features & + VHOST_USER_PROTOCOL_F_SLAVE_SHMFD) == 0) { + return 0; + } + + if (unlikely(!vq->shm)) { + return -1; + } + + vq->used_idx = vq->vring.used->idx; + vq->inflight_num = 0; + for (i = 0; i < vq->vring.num; i++) { + if (vq->shm->inflight[i] == 0) { + continue; + } + + vq->inflight_desc[vq->inflight_num++] = i; + vq->inuse++; + } + vq->shadow_avail_idx = vq->last_avail_idx = vq->inuse + vq->used_idx; + + /* in case of I/O hang after reconnecting */ + if (eventfd_write(vq->kick_fd, 1) || + eventfd_write(vq->call_fd, 1)) { + return -1; + } + + return 0; +} + static bool vu_set_vring_kick_exec(VuDev *dev, VhostUserMsg *vmsg) { @@ -925,6 +974,10 @@ vu_set_vring_kick_exec(VuDev *dev, VhostUserMsg *vmsg) dev->vq[index].kick_fd, index); } + if (vu_check_queue_inflights(dev, &dev->vq[index])) { + vu_panic(dev, "Failed to check inflights for vq: %d\n", index); + } + return false; } @@ -1215,6 +1268,115 @@ vu_set_postcopy_end(VuDev *dev, VhostUserMsg *vmsg) return true; } +static int +vu_setup_shm(VuDev *dev) +{ + int i; + char *addr = (char *)dev->shm_info.addr; + uint64_t size = 0; + uint32_t vq_size = ALIGN_UP(dev->shm_info.vq_size, dev->shm_info.align); + + if (dev->shm_info.version != SHM_VERSION) { + DPRINT("Invalid version for shm: %d", dev->shm_info.version); + return -1; + } + + if (dev->shm_info.dev_size != 0) { + DPRINT("Invalid dev_size for shm: %d", dev->shm_info.dev_size); + return -1; + } + + if (dev->shm_info.vq_size != sizeof(VuVirtqShm)) { + DPRINT("Invalid vq_size for shm: %d", dev->shm_info.vq_size); + return -1; + } + + for (i = 0; i < VHOST_MAX_NR_VIRTQUEUE; i++) { + size += vq_size; + if (size > dev->shm_info.mmap_size) { + break; + } + dev->vq[i].shm = (VuVirtqShm *)addr; + addr += vq_size; + } + + return 0; +} + +static bool +vu_get_shm_size(VuDev *dev, VhostUserMsg *vmsg) +{ + if (vmsg->size != sizeof(vmsg->payload.shm)) { + vu_panic(dev, "Invalid get_shm_size message:%d", vmsg->size); + vmsg->size = 0; + return true; + } + + vmsg->payload.shm.dev_size = 0; + vmsg->payload.shm.vq_size = sizeof(VuVirtqShm); + vmsg->payload.shm.align = SHM_ALIGNMENT; + vmsg->payload.shm.version = SHM_VERSION; + + DPRINT("send shm dev_size: %"PRId32"\n", vmsg->payload.shm.dev_size); + DPRINT("send shm vq_size: %"PRId32"\n", vmsg->payload.shm.vq_size); + DPRINT("send shm align: %"PRId32"\n", vmsg->payload.shm.align); + DPRINT("send shm version: %"PRId32"\n", vmsg->payload.shm.version); + + return true; +} + +static bool +vu_set_shm_fd(VuDev *dev, VhostUserMsg *vmsg) +{ + int fd; + uint64_t mmap_size, mmap_offset; + void *rc; + + if (vmsg->fd_num != 1 || + vmsg->size != sizeof(vmsg->payload.shm)) { + vu_panic(dev, "Invalid set_shm_fd message size:%d fds:%d", + vmsg->size, vmsg->fd_num); + return false; + } + + fd = vmsg->fds[0]; + mmap_size = vmsg->payload.shm.mmap_size; + mmap_offset = vmsg->payload.shm.mmap_offset; + DPRINT("set_shm_fd mmap_size: %"PRId64"\n", mmap_size); + DPRINT("set_shm_fd mmap_offset: %"PRId64"\n", mmap_offset); + DPRINT("set_shm_fd dev_size: %"PRId32"\n", vmsg->payload.shm.dev_size); + DPRINT("set_shm_fd vq_size: %"PRId32"\n", vmsg->payload.shm.vq_size); + DPRINT("set_shm_fd align: %"PRId32"\n", vmsg->payload.shm.align); + DPRINT("set_shm_fd version: %"PRId32"\n", vmsg->payload.shm.version); + + rc = mmap(0, mmap_size, PROT_READ | PROT_WRITE, MAP_SHARED, + fd, mmap_offset); + + close(fd); + + if (rc == MAP_FAILED) { + vu_panic(dev, "set_shm_fd mmap error: %s", strerror(errno)); + return false; + } + + if (dev->shm_info.addr) { + munmap(dev->shm_info.addr, dev->shm_info.mmap_size); + } + dev->shm_info.addr = rc; + dev->shm_info.mmap_size = mmap_size; + dev->shm_info.dev_size = vmsg->payload.shm.dev_size; + dev->shm_info.vq_size = vmsg->payload.shm.vq_size; + dev->shm_info.align = vmsg->payload.shm.align; + dev->shm_info.version = vmsg->payload.shm.version; + + if (vu_setup_shm(dev)) { + vu_panic(dev, "setup shm failed"); + return false; + } + + return false; +} + static bool vu_process_message(VuDev *dev, VhostUserMsg *vmsg) { @@ -1292,6 +1454,10 @@ vu_process_message(VuDev *dev, VhostUserMsg *vmsg) return vu_set_postcopy_listen(dev, vmsg); case VHOST_USER_POSTCOPY_END: return vu_set_postcopy_end(dev, vmsg); + case VHOST_USER_GET_SHM_SIZE: + return vu_get_shm_size(dev, vmsg); + case VHOST_USER_SET_SHM_FD: + return vu_set_shm_fd(dev, vmsg); default: vmsg_close_fds(vmsg); vu_panic(dev, "Unhandled request: %d", vmsg->request); @@ -1359,8 +1525,13 @@ vu_deinit(VuDev *dev) close(vq->err_fd); vq->err_fd = -1; } + vq->shm = NULL; } + if (dev->shm_info.addr) { + munmap(dev->shm_info.addr, dev->shm_info.mmap_size); + dev->shm_info.addr = NULL; + } vu_close_log(dev); if (dev->slave_fd != -1) { @@ -1829,12 +2000,6 @@ virtqueue_map_desc(VuDev *dev, *p_num_sg = num_sg; } -/* Round number down to multiple */ -#define ALIGN_DOWN(n, m) ((n) / (m) * (m)) - -/* Round number up to multiple */ -#define ALIGN_UP(n, m) ALIGN_DOWN((n) + (m) - 1, (m)) - static void * virtqueue_alloc_element(size_t sz, unsigned out_num, unsigned in_num) @@ -1935,9 +2100,44 @@ vu_queue_map_desc(VuDev *dev, VuVirtq *vq, unsigned int idx, size_t sz) return elem; } +static int +vu_queue_inflight_get(VuDev *dev, VuVirtq *vq, int desc_idx) +{ + if ((dev->protocol_features & + VHOST_USER_PROTOCOL_F_SLAVE_SHMFD) == 0) { + return 0; + } + + if (unlikely(!vq->shm)) { + return -1; + } + + vq->shm->inflight[desc_idx] = 1; + + return 0; +} + +static int +vu_queue_inflight_put(VuDev *dev, VuVirtq *vq, int desc_idx) +{ + if ((dev->protocol_features & + VHOST_USER_PROTOCOL_F_SLAVE_SHMFD) == 0) { + return 0; + } + + if (unlikely(!vq->shm)) { + return -1; + } + + vq->shm->inflight[desc_idx] = 0; + + return 0; +} + void * vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) { + int i; unsigned int head; VuVirtqElement *elem; @@ -1946,6 +2146,12 @@ vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) return NULL; } + if (unlikely(vq->inflight_num > 0)) { + i = (--vq->inflight_num); + elem = vu_queue_map_desc(dev, vq, vq->inflight_desc[i], sz); + return elem; + } + if (vu_queue_empty(dev, vq)) { return NULL; } @@ -1976,6 +2182,8 @@ vu_queue_pop(VuDev *dev, VuVirtq *vq, size_t sz) vq->inuse++; + vu_queue_inflight_get(dev, vq, head); + return elem; } @@ -2121,4 +2329,5 @@ vu_queue_push(VuDev *dev, VuVirtq *vq, { vu_queue_fill(dev, vq, elem, len, 0); vu_queue_flush(dev, vq, 1); + vu_queue_inflight_put(dev, vq, elem->index); } diff --git a/contrib/libvhost-user/libvhost-user.h b/contrib/libvhost-user/libvhost-user.h index 4aa55b4d2d..fdfda688d2 100644 --- a/contrib/libvhost-user/libvhost-user.h +++ b/contrib/libvhost-user/libvhost-user.h @@ -53,6 +53,7 @@ enum VhostUserProtocolFeature { VHOST_USER_PROTOCOL_F_CONFIG = 9, VHOST_USER_PROTOCOL_F_SLAVE_SEND_FD = 10, VHOST_USER_PROTOCOL_F_HOST_NOTIFIER = 11, + VHOST_USER_PROTOCOL_F_SLAVE_SHMFD = 12, VHOST_USER_PROTOCOL_F_MAX }; @@ -91,6 +92,8 @@ typedef enum VhostUserRequest { VHOST_USER_POSTCOPY_ADVISE = 28, VHOST_USER_POSTCOPY_LISTEN = 29, VHOST_USER_POSTCOPY_END = 30, + VHOST_USER_GET_SHM_SIZE = 31, + VHOST_USER_SET_SHM_FD = 32, VHOST_USER_MAX } VhostUserRequest; @@ -138,6 +141,15 @@ typedef struct VhostUserVringArea { uint64_t offset; } VhostUserVringArea; +typedef struct VhostUserShm { + uint64_t mmap_size; + uint64_t mmap_offset; + uint32_t dev_size; + uint32_t vq_size; + uint32_t align; + uint32_t version; +} VhostUserShm; + #if defined(_WIN32) # define VU_PACKED __attribute__((gcc_struct, packed)) #else @@ -163,6 +175,7 @@ typedef struct VhostUserMsg { VhostUserLog log; VhostUserConfig config; VhostUserVringArea area; + VhostUserShm shm; } payload; int fds[VHOST_MEMORY_MAX_NREGIONS]; @@ -234,9 +247,19 @@ typedef struct VuRing { uint32_t flags; } VuRing; +typedef struct VuVirtqShm { + char inflight[VIRTQUEUE_MAX_SIZE]; +} VuVirtqShm; + typedef struct VuVirtq { VuRing vring; + VuVirtqShm *shm; + + uint16_t inflight_desc[VIRTQUEUE_MAX_SIZE]; + + uint16_t inflight_num; + /* Next head to pop */ uint16_t last_avail_idx; @@ -279,11 +302,21 @@ typedef void (*vu_set_watch_cb) (VuDev *dev, int fd, int condition, vu_watch_cb cb, void *data); typedef void (*vu_remove_watch_cb) (VuDev *dev, int fd); +typedef struct VuDevShmInfo { + void *addr; + uint64_t mmap_size; + uint32_t dev_size; + uint32_t vq_size; + uint32_t align; + uint32_t version; +} VuDevShmInfo; + struct VuDev { int sock; uint32_t nregions; VuDevRegion regions[VHOST_MEMORY_MAX_NREGIONS]; VuVirtq vq[VHOST_MAX_NR_VIRTQUEUE]; + VuDevShmInfo shm_info; int log_call_fd; int slave_fd; uint64_t log_size;

[v2,for-4.0,4/7] libvhost-user: Support recording inflight I/O in shared memory

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