Previously, for the fsdax mem-backend-file, it will register failed with Operation not supported. In this case, we can try to register it with On-Demand Paging[1] like what rpma_mr_reg() does on rpma[2].
[1]: https://community.mellanox.com/s/article/understanding-on-demand-paging--odp-x [2]: http://pmem.io/rpma/manpages/v0.9.0/rpma_mr_reg.3 CC: Marcel Apfelbaum <marcel.apfelb...@gmail.com> Signed-off-by: Li Zhijian <lizhij...@cn.fujitsu.com> Reviewed-by: Marcel Apfelbaum <marcel.apfelb...@gmail.com> --- V2: add ODP sanity check and remove goto --- migration/rdma.c | 73 ++++++++++++++++++++++++++++++------------ migration/trace-events | 1 + 2 files changed, 54 insertions(+), 20 deletions(-) diff --git a/migration/rdma.c b/migration/rdma.c index 5c2d113aa94..eb80431aae2 100644 --- a/migration/rdma.c +++ b/migration/rdma.c @@ -1117,19 +1117,47 @@ static int qemu_rdma_alloc_qp(RDMAContext *rdma) return 0; } +/* Check whether On-Demand Paging is supported by RDAM device */ +static bool rdma_support_odp(struct ibv_context *dev) +{ + struct ibv_device_attr_ex attr = {0}; + int ret = ibv_query_device_ex(dev, NULL, &attr); + if (ret) { + return false; + } + + if (attr.odp_caps.general_caps & IBV_ODP_SUPPORT) { + return true; + } + + return false; +} + static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma) { int i; RDMALocalBlocks *local = &rdma->local_ram_blocks; for (i = 0; i < local->nb_blocks; i++) { + int access = IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE; + local->block[i].mr = ibv_reg_mr(rdma->pd, local->block[i].local_host_addr, - local->block[i].length, - IBV_ACCESS_LOCAL_WRITE | - IBV_ACCESS_REMOTE_WRITE + local->block[i].length, access ); + + if (!local->block[i].mr && + errno == ENOTSUP && rdma_support_odp(rdma->verbs)) { + access |= IBV_ACCESS_ON_DEMAND; + /* register ODP mr */ + local->block[i].mr = + ibv_reg_mr(rdma->pd, + local->block[i].local_host_addr, + local->block[i].length, access); + trace_qemu_rdma_register_odp_mr(local->block[i].block_name); + } + if (!local->block[i].mr) { perror("Failed to register local dest ram block!"); break; @@ -1215,28 +1243,33 @@ static int qemu_rdma_register_and_get_keys(RDMAContext *rdma, */ if (!block->pmr[chunk]) { uint64_t len = chunk_end - chunk_start; + int access = rkey ? IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE : + 0; trace_qemu_rdma_register_and_get_keys(len, chunk_start); - block->pmr[chunk] = ibv_reg_mr(rdma->pd, - chunk_start, len, - (rkey ? (IBV_ACCESS_LOCAL_WRITE | - IBV_ACCESS_REMOTE_WRITE) : 0)); - - if (!block->pmr[chunk]) { - perror("Failed to register chunk!"); - fprintf(stderr, "Chunk details: block: %d chunk index %d" - " start %" PRIuPTR " end %" PRIuPTR - " host %" PRIuPTR - " local %" PRIuPTR " registrations: %d\n", - block->index, chunk, (uintptr_t)chunk_start, - (uintptr_t)chunk_end, host_addr, - (uintptr_t)block->local_host_addr, - rdma->total_registrations); - return -1; + block->pmr[chunk] = ibv_reg_mr(rdma->pd, chunk_start, len, access); + if (!block->pmr[chunk] && + errno == ENOTSUP && rdma_support_odp(rdma->verbs)) { + access |= IBV_ACCESS_ON_DEMAND; + /* register ODP mr */ + block->pmr[chunk] = ibv_reg_mr(rdma->pd, chunk_start, len, access); + trace_qemu_rdma_register_odp_mr(block->block_name); } - rdma->total_registrations++; } + if (!block->pmr[chunk]) { + perror("Failed to register chunk!"); + fprintf(stderr, "Chunk details: block: %d chunk index %d" + " start %" PRIuPTR " end %" PRIuPTR + " host %" PRIuPTR + " local %" PRIuPTR " registrations: %d\n", + block->index, chunk, (uintptr_t)chunk_start, + (uintptr_t)chunk_end, host_addr, + (uintptr_t)block->local_host_addr, + rdma->total_registrations); + return -1; + } + rdma->total_registrations++; if (lkey) { *lkey = block->pmr[chunk]->lkey; diff --git a/migration/trace-events b/migration/trace-events index a1c0f034ab8..5f6aa580def 100644 --- a/migration/trace-events +++ b/migration/trace-events @@ -212,6 +212,7 @@ qemu_rdma_poll_write(const char *compstr, int64_t comp, int left, uint64_t block qemu_rdma_poll_other(const char *compstr, int64_t comp, int left) "other completion %s (%" PRId64 ") received left %d" qemu_rdma_post_send_control(const char *desc) "CONTROL: sending %s.." qemu_rdma_register_and_get_keys(uint64_t len, void *start) "Registering %" PRIu64 " bytes @ %p" +qemu_rdma_register_odp_mr(const char *name) "Try to register On-Demand Paging memory region: %s" qemu_rdma_registration_handle_compress(int64_t length, int index, int64_t offset) "Zapping zero chunk: %" PRId64 " bytes, index %d, offset %" PRId64 qemu_rdma_registration_handle_finished(void) "" qemu_rdma_registration_handle_ram_blocks(void) "" -- 2.31.1
