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 Signed-off-by: Li Zhijian <lizhij...@cn.fujitsu.com> --- migration/rdma.c | 27 ++++++++++++++++++--------- migration/trace-events | 1 + 2 files changed, 19 insertions(+), 9 deletions(-) diff --git a/migration/rdma.c b/migration/rdma.c index 5c2d113aa94..8784b5f22a6 100644 --- a/migration/rdma.c +++ b/migration/rdma.c @@ -1123,15 +1123,21 @@ static int qemu_rdma_reg_whole_ram_blocks(RDMAContext *rdma) RDMALocalBlocks *local = &rdma->local_ram_blocks; for (i = 0; i < local->nb_blocks; i++) { + int access = IBV_ACCESS_LOCAL_WRITE | IBV_ACCESS_REMOTE_WRITE; + +on_demand: 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) { - perror("Failed to register local dest ram block!"); + if (!(access & IBV_ACCESS_ON_DEMAND) && errno == ENOTSUP) { + access |= IBV_ACCESS_ON_DEMAND; + trace_qemu_rdma_register_odp_mr(local->block[i].block_name); + goto on_demand; + } + perror("Failed to register local dest ram block!\n"); break; } rdma->total_registrations++; @@ -1215,15 +1221,18 @@ 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)); - +on_demand: + block->pmr[chunk] = ibv_reg_mr(rdma->pd, chunk_start, len, access); if (!block->pmr[chunk]) { + if (!(access & IBV_ACCESS_ON_DEMAND) && errno == ENOTSUP) { + access |= IBV_ACCESS_ON_DEMAND; + trace_qemu_rdma_register_odp_mr(block->block_name); + goto on_demand; + } perror("Failed to register chunk!"); fprintf(stderr, "Chunk details: block: %d chunk index %d" " start %" PRIuPTR " end %" PRIuPTR 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