Hi On Sat, Jul 31, 2021 at 5:00 PM Li Zhijian <lizhij...@cn.fujitsu.com> wrote: > > 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;
Wouldn't it be better to check first if the device supports ODP ? Something like: ret = ibv_exp_query_device(context, &dattr); if (dattr.exp_device_cap_flags & IBV_EXP_DEVICE_ODP)... Also, I am not (personally) too fond of the "on_demand" label usage here, however I will let the maintainer/others decide. Thanks, Marcel > + } > + 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 > > > >