From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: MIME-Version: 1.0 In-Reply-To: References: <20180202140904.2017-1-roman.penyaev@profitbricks.com> <20180202140904.2017-6-roman.penyaev@profitbricks.com> From: Roman Penyaev Date: Mon, 5 Feb 2018 15:19:12 +0100 Message-ID: Subject: Re: [PATCH 05/24] ibtrs: client: main functionality To: Sagi Grimberg Cc: linux-block@vger.kernel.org, linux-rdma@vger.kernel.org, Jens Axboe , Christoph Hellwig , Bart Van Assche , Or Gerlitz , Danil Kipnis , Jack Wang Content-Type: text/plain; charset="UTF-8" List-ID: Hi Sagi, On Mon, Feb 5, 2018 at 12:19 PM, Sagi Grimberg wrote: > Hi Roman, > >> +static inline void ibtrs_clt_state_lock(void) >> +{ >> + rcu_read_lock(); >> +} >> + >> +static inline void ibtrs_clt_state_unlock(void) >> +{ >> + rcu_read_unlock(); >> +} > > > This looks rather pointless... Yeah, old scraps. Some time later those were not only wrappers around rcu. Now rcu can be called explicitly, that is true. Thanks. > >> + >> +#define cmpxchg_min(var, new) ({ \ >> + typeof(var) old; \ >> + \ >> + do { \ >> + old = var; \ >> + new = (!old ? new : min_t(typeof(var), old, new)); \ >> + } while (cmpxchg(&var, old, new) != old); \ >> +}) > > > Why is this sort of thing local to your driver? Good question :) Most likely because personally I do not know what is the good generic place for this kind of stuff. Probably I share the same feeling with the author of these lines in nvme/host/rdma.c: put_unaligned_le24() :) >> +/** >> + * struct ibtrs_fr_pool - pool of fast registration descriptors >> + * >> + * An entry is available for allocation if and only if it occurs in >> @free_list. >> + * >> + * @size: Number of descriptors in this pool. >> + * @max_page_list_len: Maximum fast registration work request page list >> length. >> + * @lock: Protects free_list. >> + * @free_list: List of free descriptors. >> + * @desc: Fast registration descriptor pool. >> + */ >> +struct ibtrs_fr_pool { >> + int size; >> + int max_page_list_len; >> + spinlock_t lock; /* protects free_list */ >> + struct list_head free_list; >> + struct ibtrs_fr_desc desc[0]; >> +}; > > > We already have a per-qp fr list implementation, any specific reason to > implement it again? No, fr is a part of the code which we are not using, fmr is faster in our setup. So we will need to reiterate on fr mode, thanks. >> +static inline struct ibtrs_tag * >> +__ibtrs_get_tag(struct ibtrs_clt *clt, enum ibtrs_clt_con_type con_type) >> +{ >> + size_t max_depth = clt->queue_depth; >> + struct ibtrs_tag *tag; >> + int cpu, bit; >> + >> + cpu = get_cpu(); >> + do { >> + bit = find_first_zero_bit(clt->tags_map, max_depth); >> + if (unlikely(bit >= max_depth)) { >> + put_cpu(); >> + return NULL; >> + } >> + >> + } while (unlikely(test_and_set_bit_lock(bit, clt->tags_map))); >> + put_cpu(); >> + >> + tag = GET_TAG(clt, bit); >> + WARN_ON(tag->mem_id != bit); >> + tag->cpu_id = cpu; >> + tag->con_type = con_type; >> + >> + return tag; >> +} >> + >> +static inline void __ibtrs_put_tag(struct ibtrs_clt *clt, >> + struct ibtrs_tag *tag) >> +{ >> + clear_bit_unlock(tag->mem_id, clt->tags_map); >> +} >> + >> +struct ibtrs_tag *ibtrs_clt_get_tag(struct ibtrs_clt *clt, >> + enum ibtrs_clt_con_type con_type, >> + int can_wait) >> +{ >> + struct ibtrs_tag *tag; >> + DEFINE_WAIT(wait); >> + >> + tag = __ibtrs_get_tag(clt, con_type); >> + if (likely(tag) || !can_wait) >> + return tag; >> + >> + do { >> + prepare_to_wait(&clt->tags_wait, &wait, >> TASK_UNINTERRUPTIBLE); >> + tag = __ibtrs_get_tag(clt, con_type); >> + if (likely(tag)) >> + break; >> + >> + io_schedule(); >> + } while (1); >> + >> + finish_wait(&clt->tags_wait, &wait); >> + >> + return tag; >> +} >> +EXPORT_SYMBOL(ibtrs_clt_get_tag); >> + >> +void ibtrs_clt_put_tag(struct ibtrs_clt *clt, struct ibtrs_tag *tag) >> +{ >> + if (WARN_ON(!test_bit(tag->mem_id, clt->tags_map))) >> + return; >> + >> + __ibtrs_put_tag(clt, tag); >> + >> + /* >> + * Putting a tag is a barrier, so we will observe >> + * new entry in the wait list, no worries. >> + */ >> + if (waitqueue_active(&clt->tags_wait)) >> + wake_up(&clt->tags_wait); >> +} >> +EXPORT_SYMBOL(ibtrs_clt_put_tag); > > > Again, the tags are not clear why they are needed... We have two separate instances: block device (IBNBD) and a transport library (IBTRS). Many block devices share the same IBTRS session with fixed size queue depth. Tags is a part of IBTRS, so with allocated tag you get a free slot of a buffer where you can read/write, so once you've allocated a tag you won't sleep on IO path inside a library. Also tag helps a lot on IO fail-over to another connection (multipath implementation, which is also a part of the transport library, not a block device), where you simply reuse the same buffer slot (with a tag in your hands) forwarding IO to another RDMA connection. >> +/** >> + * ibtrs_destroy_fr_pool() - free the resources owned by a pool >> + * @pool: Fast registration pool to be destroyed. >> + */ >> +static void ibtrs_destroy_fr_pool(struct ibtrs_fr_pool *pool) >> +{ >> + struct ibtrs_fr_desc *d; >> + int i, err; >> + >> + if (!pool) >> + return; >> + >> + for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) { >> + if (d->mr) { >> + err = ib_dereg_mr(d->mr); >> + if (err) >> + pr_err("Failed to deregister memory >> region," >> + " err: %d\n", err); >> + } >> + } >> + kfree(pool); >> +} >> + >> +/** >> + * ibtrs_create_fr_pool() - allocate and initialize a pool for fast >> registration >> + * @device: IB device to allocate fast registration >> descriptors for. >> + * @pd: Protection domain associated with the FR >> descriptors. >> + * @pool_size: Number of descriptors to allocate. >> + * @max_page_list_len: Maximum fast registration work request page list >> length. >> + */ >> +static struct ibtrs_fr_pool *ibtrs_create_fr_pool(struct ib_device >> *device, >> + struct ib_pd *pd, >> + int pool_size, >> + int max_page_list_len) >> +{ >> + struct ibtrs_fr_pool *pool; >> + struct ibtrs_fr_desc *d; >> + struct ib_mr *mr; >> + int i, ret; >> + >> + if (pool_size <= 0) { >> + pr_warn("Creating fr pool failed, invalid pool size %d\n", >> + pool_size); >> + ret = -EINVAL; >> + goto err; >> + } >> + >> + pool = kzalloc(sizeof(*pool) + pool_size * sizeof(*d), >> GFP_KERNEL); >> + if (!pool) { >> + ret = -ENOMEM; >> + goto err; >> + } >> + >> + pool->size = pool_size; >> + pool->max_page_list_len = max_page_list_len; >> + spin_lock_init(&pool->lock); >> + INIT_LIST_HEAD(&pool->free_list); >> + >> + for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) { >> + mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, >> max_page_list_len); >> + if (IS_ERR(mr)) { >> + pr_warn("Failed to allocate fast region >> memory\n"); >> + ret = PTR_ERR(mr); >> + goto destroy_pool; >> + } >> + d->mr = mr; >> + list_add_tail(&d->entry, &pool->free_list); >> + } >> + >> + return pool; >> + >> +destroy_pool: >> + ibtrs_destroy_fr_pool(pool); >> +err: >> + return ERR_PTR(ret); >> +} >> + >> +/** >> + * ibtrs_fr_pool_get() - obtain a descriptor suitable for fast >> registration >> + * @pool: Pool to obtain descriptor from. >> + */ >> +static struct ibtrs_fr_desc *ibtrs_fr_pool_get(struct ibtrs_fr_pool >> *pool) >> +{ >> + struct ibtrs_fr_desc *d = NULL; >> + >> + spin_lock_bh(&pool->lock); >> + if (!list_empty(&pool->free_list)) { >> + d = list_first_entry(&pool->free_list, typeof(*d), entry); >> + list_del(&d->entry); >> + } >> + spin_unlock_bh(&pool->lock); >> + >> + return d; >> +} >> + >> +/** >> + * ibtrs_fr_pool_put() - put an FR descriptor back in the free list >> + * @pool: Pool the descriptor was allocated from. >> + * @desc: Pointer to an array of fast registration descriptor pointers. >> + * @n: Number of descriptors to put back. >> + * >> + * Note: The caller must already have queued an invalidation request for >> + * desc->mr->rkey before calling this function. >> + */ >> +static void ibtrs_fr_pool_put(struct ibtrs_fr_pool *pool, >> + struct ibtrs_fr_desc **desc, int n) >> +{ >> + int i; >> + >> + spin_lock_bh(&pool->lock); >> + for (i = 0; i < n; i++) >> + list_add(&desc[i]->entry, &pool->free_list); >> + spin_unlock_bh(&pool->lock); >> +} >> + >> +static void ibtrs_map_desc(struct ibtrs_map_state *state, dma_addr_t >> dma_addr, >> + u32 dma_len, u32 rkey, u32 max_desc) >> +{ >> + struct ibtrs_sg_desc *desc = state->desc; >> + >> + pr_debug("dma_addr %llu, key %u, dma_len %u\n", >> + dma_addr, rkey, dma_len); >> + desc->addr = cpu_to_le64(dma_addr); >> + desc->key = cpu_to_le32(rkey); >> + desc->len = cpu_to_le32(dma_len); >> + >> + state->total_len += dma_len; >> + if (state->ndesc < max_desc) { >> + state->desc++; >> + state->ndesc++; >> + } else { >> + state->ndesc = INT_MIN; >> + pr_err("Could not fit S/G list into buffer descriptor >> %d.\n", >> + max_desc); >> + } >> +} >> + >> +static int ibtrs_map_finish_fmr(struct ibtrs_map_state *state, >> + struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ib_pool_fmr *fmr; >> + dma_addr_t dma_addr; >> + u64 io_addr = 0; >> + >> + fmr = ib_fmr_pool_map_phys(sess->fmr_pool, state->pages, >> + state->npages, io_addr); >> + if (IS_ERR(fmr)) { >> + ibtrs_wrn_rl(sess, "Failed to map FMR from FMR pool, " >> + "err: %ld\n", PTR_ERR(fmr)); >> + return PTR_ERR(fmr); >> + } >> + >> + *state->next_fmr++ = fmr; >> + state->nmdesc++; >> + dma_addr = state->base_dma_addr & ~sess->mr_page_mask; >> + pr_debug("ndesc = %d, nmdesc = %d, npages = %d\n", >> + state->ndesc, state->nmdesc, state->npages); >> + if (state->dir == DMA_TO_DEVICE) >> + ibtrs_map_desc(state, dma_addr, state->dma_len, >> fmr->fmr->lkey, >> + sess->max_desc); >> + else >> + ibtrs_map_desc(state, dma_addr, state->dma_len, >> fmr->fmr->rkey, >> + sess->max_desc); >> + >> + return 0; >> +} >> + >> +static void ibtrs_clt_fast_reg_done(struct ib_cq *cq, struct ib_wc *wc) >> +{ >> + struct ibtrs_clt_con *con = cq->cq_context; >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + >> + if (unlikely(wc->status != IB_WC_SUCCESS)) { >> + ibtrs_err(sess, "Failed IB_WR_REG_MR: %s\n", >> + ib_wc_status_msg(wc->status)); >> + ibtrs_rdma_error_recovery(con); >> + } >> +} >> + >> +static struct ib_cqe fast_reg_cqe = { >> + .done = ibtrs_clt_fast_reg_done >> +}; >> + >> +/* TODO */ >> +static int ibtrs_map_finish_fr(struct ibtrs_map_state *state, >> + struct ibtrs_clt_con *con, int sg_cnt, >> + unsigned int *sg_offset_p) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ibtrs_fr_desc *desc; >> + struct ib_send_wr *bad_wr; >> + struct ib_reg_wr wr; >> + struct ib_pd *pd; >> + u32 rkey; >> + int n; >> + >> + pd = sess->s.ib_dev->pd; >> + if (sg_cnt == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) { >> + unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0; >> + >> + ibtrs_map_desc(state, sg_dma_address(state->sg) + >> sg_offset, >> + sg_dma_len(state->sg) - sg_offset, >> + pd->unsafe_global_rkey, sess->max_desc); >> + if (sg_offset_p) >> + *sg_offset_p = 0; >> + return 1; >> + } >> + >> + desc = ibtrs_fr_pool_get(con->fr_pool); >> + if (!desc) { >> + ibtrs_wrn_rl(sess, "Failed to get descriptor from FR >> pool\n"); >> + return -ENOMEM; >> + } >> + >> + rkey = ib_inc_rkey(desc->mr->rkey); >> + ib_update_fast_reg_key(desc->mr, rkey); >> + >> + memset(&wr, 0, sizeof(wr)); >> + n = ib_map_mr_sg(desc->mr, state->sg, sg_cnt, sg_offset_p, >> + sess->mr_page_size); >> + if (unlikely(n < 0)) { >> + ibtrs_fr_pool_put(con->fr_pool, &desc, 1); >> + return n; >> + } >> + >> + wr.wr.next = NULL; >> + wr.wr.opcode = IB_WR_REG_MR; >> + wr.wr.wr_cqe = &fast_reg_cqe; >> + wr.wr.num_sge = 0; >> + wr.wr.send_flags = 0; >> + wr.mr = desc->mr; >> + wr.key = desc->mr->rkey; >> + wr.access = (IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE); > > > Do you actually ever have remote write access in your protocol? We do not have reads, instead client writes on write and server writes on read. (write only storage solution :) > >> +static void ibtrs_clt_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc) >> +{ >> + struct ibtrs_clt_con *con = cq->cq_context; >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + >> + if (unlikely(wc->status != IB_WC_SUCCESS)) { >> + ibtrs_err(sess, "Failed IB_WR_LOCAL_INV: %s\n", >> + ib_wc_status_msg(wc->status)); >> + ibtrs_rdma_error_recovery(con); >> + } >> +} >> + >> +static struct ib_cqe local_inv_cqe = { >> + .done = ibtrs_clt_inv_rkey_done >> +}; >> + >> +static int ibtrs_inv_rkey(struct ibtrs_clt_con *con, u32 rkey) >> +{ >> + struct ib_send_wr *bad_wr; >> + struct ib_send_wr wr = { >> + .opcode = IB_WR_LOCAL_INV, >> + .wr_cqe = &local_inv_cqe, >> + .next = NULL, >> + .num_sge = 0, >> + .send_flags = 0, >> + .ex.invalidate_rkey = rkey, >> + }; >> + >> + return ib_post_send(con->c.qp, &wr, &bad_wr); >> +} > > > Is not signalling the local invalidate safe? A recent report > suggested that this is not safe in the presence of ack drops. For our setup we use fmr, so frankly I do not follow any fr discussions. Could you please provide the link? >> +static int ibtrs_post_send_rdma(struct ibtrs_clt_con *con, >> + struct ibtrs_clt_io_req *req, >> + u64 addr, u32 off, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + enum ib_send_flags flags; >> + struct ib_sge list[1]; >> + >> + if (unlikely(!req->sg_size)) { >> + ibtrs_wrn(sess, "Doing RDMA Write failed, no data >> supplied\n"); >> + return -EINVAL; >> + } >> + >> + /* user data and user message in the first list element */ >> + list[0].addr = req->iu->dma_addr; >> + list[0].length = req->sg_size; >> + list[0].lkey = sess->s.ib_dev->lkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + return ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, 1, >> + sess->srv_rdma_buf_rkey, >> + addr + off, imm, flags); >> +} >> + >> +static void ibtrs_set_sge_with_desc(struct ib_sge *list, >> + struct ibtrs_sg_desc *desc) >> +{ >> + list->addr = le64_to_cpu(desc->addr); >> + list->length = le32_to_cpu(desc->len); >> + list->lkey = le32_to_cpu(desc->key); >> + pr_debug("dma_addr %llu, key %u, dma_len %u\n", >> + list->addr, list->lkey, list->length); >> +} >> + >> +static void ibtrs_set_rdma_desc_last(struct ibtrs_clt_con *con, >> + struct ib_sge *list, >> + struct ibtrs_clt_io_req *req, >> + struct ib_rdma_wr *wr, int offset, >> + struct ibtrs_sg_desc *desc, int m, >> + int n, u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + enum ib_send_flags flags; >> + int i; >> + >> + for (i = m; i < n; i++, desc++) >> + ibtrs_set_sge_with_desc(&list[i], desc); >> + >> + list[i].addr = req->iu->dma_addr; >> + list[i].length = size; >> + list[i].lkey = sess->s.ib_dev->lkey; >> + >> + wr->wr.wr_cqe = &req->iu->cqe; >> + wr->wr.sg_list = &list[m]; >> + wr->wr.num_sge = n - m + 1; >> + wr->remote_addr = addr + offset; >> + wr->rkey = sess->srv_rdma_buf_rkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + >> + wr->wr.opcode = IB_WR_RDMA_WRITE_WITH_IMM; >> + wr->wr.send_flags = flags; >> + wr->wr.ex.imm_data = cpu_to_be32(imm); >> +} >> + >> +static int ibtrs_post_send_rdma_desc_more(struct ibtrs_clt_con *con, >> + struct ib_sge *list, >> + struct ibtrs_clt_io_req *req, >> + struct ibtrs_sg_desc *desc, int >> n, >> + u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + size_t max_sge, num_sge, num_wr; >> + struct ib_send_wr *bad_wr; >> + struct ib_rdma_wr *wrs, *wr; >> + int j = 0, k, offset = 0, len = 0; >> + int m = 0; >> + int ret; >> + >> + max_sge = sess->max_sge; >> + num_sge = 1 + n; >> + num_wr = DIV_ROUND_UP(num_sge, max_sge); >> + >> + wrs = kcalloc(num_wr, sizeof(*wrs), GFP_ATOMIC); >> + if (!wrs) >> + return -ENOMEM; >> + >> + if (num_wr == 1) >> + goto last_one; >> + >> + for (; j < num_wr; j++) { >> + wr = &wrs[j]; >> + for (k = 0; k < max_sge; k++, desc++) { >> + m = k + j * max_sge; >> + ibtrs_set_sge_with_desc(&list[m], desc); >> + len += le32_to_cpu(desc->len); >> + } >> + wr->wr.wr_cqe = &req->iu->cqe; >> + wr->wr.sg_list = &list[m]; >> + wr->wr.num_sge = max_sge; >> + wr->remote_addr = addr + offset; >> + wr->rkey = sess->srv_rdma_buf_rkey; >> + >> + offset += len; >> + wr->wr.next = &wrs[j + 1].wr; >> + wr->wr.opcode = IB_WR_RDMA_WRITE; >> + } >> + >> +last_one: >> + wr = &wrs[j]; >> + >> + ibtrs_set_rdma_desc_last(con, list, req, wr, offset, >> + desc, m, n, addr, size, imm); >> + >> + ret = ib_post_send(con->c.qp, &wrs[0].wr, &bad_wr); >> + if (unlikely(ret)) >> + ibtrs_err(sess, "Posting write request to QP failed," >> + " err: %d\n", ret); >> + kfree(wrs); >> + return ret; >> +} >> + >> +static int ibtrs_post_send_rdma_desc(struct ibtrs_clt_con *con, >> + struct ibtrs_clt_io_req *req, >> + struct ibtrs_sg_desc *desc, int n, >> + u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + enum ib_send_flags flags; >> + struct ib_sge *list; >> + size_t num_sge; >> + int ret, i; >> + >> + num_sge = 1 + n; >> + list = kmalloc_array(num_sge, sizeof(*list), GFP_ATOMIC); >> + if (!list) >> + return -ENOMEM; >> + >> + if (num_sge < sess->max_sge) { >> + for (i = 0; i < n; i++, desc++) >> + ibtrs_set_sge_with_desc(&list[i], desc); >> + list[i].addr = req->iu->dma_addr; >> + list[i].length = size; >> + list[i].lkey = sess->s.ib_dev->lkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % >> sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + ret = ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, >> + num_sge, >> + >> sess->srv_rdma_buf_rkey, >> + addr, imm, flags); >> + } else { >> + ret = ibtrs_post_send_rdma_desc_more(con, list, req, desc, >> n, >> + addr, size, imm); >> + } >> + >> + kfree(list); >> + return ret; >> +} >> + >> +static int ibtrs_post_send_rdma_more(struct ibtrs_clt_con *con, >> + struct ibtrs_clt_io_req *req, >> + u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ib_device *ibdev = sess->s.ib_dev->dev; >> + enum ib_send_flags flags; >> + struct scatterlist *sg; >> + struct ib_sge *list; >> + size_t num_sge; >> + int i, ret; >> + >> + num_sge = 1 + req->sg_cnt; >> + list = kmalloc_array(num_sge, sizeof(*list), GFP_ATOMIC); >> + if (!list) >> + return -ENOMEM; >> + >> + for_each_sg(req->sglist, sg, req->sg_cnt, i) { >> + list[i].addr = ib_sg_dma_address(ibdev, sg); >> + list[i].length = ib_sg_dma_len(ibdev, sg); >> + list[i].lkey = sess->s.ib_dev->lkey; >> + } >> + list[i].addr = req->iu->dma_addr; >> + list[i].length = size; >> + list[i].lkey = sess->s.ib_dev->lkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + ret = ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, >> num_sge, >> + sess->srv_rdma_buf_rkey, >> + addr, imm, flags); >> + kfree(list); >> + >> + return ret; >> +} > > > All these rdma halpers looks like that can be reused from the rdma rw > API if it was enhanced with immediate capabilities. True. >> +static inline unsigned long ibtrs_clt_get_raw_ms(void) >> +{ >> + struct timespec ts; >> + >> + getrawmonotonic(&ts); >> + >> + return timespec_to_ns(&ts) / NSEC_PER_MSEC; >> +} > > > Why is this local to your driver? > >> + >> +static void complete_rdma_req(struct ibtrs_clt_io_req *req, >> + int errno, bool notify) >> +{ >> + struct ibtrs_clt_con *con = req->con; >> + struct ibtrs_clt_sess *sess; >> + enum dma_data_direction dir; >> + struct ibtrs_clt *clt; >> + void *priv; >> + >> + if (WARN_ON(!req->in_use)) >> + return; >> + if (WARN_ON(!req->con)) >> + return; >> + sess = to_clt_sess(con->c.sess); >> + clt = sess->clt; >> + >> + if (req->sg_cnt > fmr_sg_cnt) >> + ibtrs_unmap_fast_reg_data(req->con, req); >> + if (req->sg_cnt) >> + ib_dma_unmap_sg(sess->s.ib_dev->dev, req->sglist, >> + req->sg_cnt, req->dir); >> + if (sess->stats.enable_rdma_lat) >> + ibtrs_clt_update_rdma_lat(&sess->stats, >> + req->dir == DMA_FROM_DEVICE, >> + ibtrs_clt_get_raw_ms() - >> + req->start_time); >> + ibtrs_clt_decrease_inflight(&sess->stats); >> + >> + req->in_use = false; >> + req->con = NULL; >> + priv = req->priv; >> + dir = req->dir; >> + >> + if (notify) >> + req->conf(priv, errno); >> +} > > > > >> + >> +static void process_io_rsp(struct ibtrs_clt_sess *sess, u32 msg_id, s16 >> errno) >> +{ >> + if (WARN_ON(msg_id >= sess->queue_depth)) >> + return; >> + >> + complete_rdma_req(&sess->reqs[msg_id], errno, true); >> +} >> + >> +static struct ib_cqe io_comp_cqe = { >> + .done = ibtrs_clt_rdma_done >> +}; >> + >> +static void ibtrs_clt_rdma_done(struct ib_cq *cq, struct ib_wc *wc) >> +{ >> + struct ibtrs_clt_con *con = cq->cq_context; >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + u32 imm_type, imm_payload; >> + int err; >> + >> + if (unlikely(wc->status != IB_WC_SUCCESS)) { >> + if (wc->status != IB_WC_WR_FLUSH_ERR) { >> + ibtrs_err(sess, "RDMA failed: %s\n", >> + ib_wc_status_msg(wc->status)); >> + ibtrs_rdma_error_recovery(con); >> + } >> + return; >> + } >> + ibtrs_clt_update_wc_stats(con); >> + >> + switch (wc->opcode) { >> + case IB_WC_RDMA_WRITE: >> + /* >> + * post_send() RDMA write completions of IO reqs >> (read/write) >> + * and hb >> + */ >> + break; >> + case IB_WC_RECV_RDMA_WITH_IMM: >> + /* >> + * post_recv() RDMA write completions of IO reqs >> (read/write) >> + * and hb >> + */ >> + if (WARN_ON(wc->wr_cqe != &io_comp_cqe)) >> + return; >> + err = ibtrs_post_recv_empty(&con->c, &io_comp_cqe); >> + if (unlikely(err)) { >> + ibtrs_err(sess, "ibtrs_post_recv_empty(): %d\n", >> err); >> + ibtrs_rdma_error_recovery(con); >> + break; >> + } >> + ibtrs_from_imm(be32_to_cpu(wc->ex.imm_data), >> + &imm_type, &imm_payload); >> + if (likely(imm_type == IBTRS_IO_RSP_IMM)) { >> + u32 msg_id; >> + >> + ibtrs_from_io_rsp_imm(imm_payload, &msg_id, &err); >> + process_io_rsp(sess, msg_id, err); >> + } else if (imm_type == IBTRS_HB_MSG_IMM) { >> + WARN_ON(con->c.cid); >> + ibtrs_send_hb_ack(&sess->s); >> + } else if (imm_type == IBTRS_HB_ACK_IMM) { >> + WARN_ON(con->c.cid); >> + sess->s.hb_missed_cnt = 0; >> + } else { >> + ibtrs_wrn(sess, "Unknown IMM type %u\n", >> imm_type); >> + } >> + break; >> + default: >> + ibtrs_wrn(sess, "Unexpected WC type: %s\n", >> + ib_wc_opcode_str(wc->opcode)); >> + return; >> + } > > > Is there a spec somewhere with the protocol information that explains > how this all works? Not yet. The transfer procedure is described in vault presentation. Is README is a good place for such stuff? I mean some low-level protocol spec. >> +struct path_it { >> + int i; >> + struct list_head skip_list; >> + struct ibtrs_clt *clt; >> + struct ibtrs_clt_sess *(*next_path)(struct path_it *); >> +}; >> + >> +#define do_each_path(path, clt, it) { \ >> + path_it_init(it, clt); \ >> + ibtrs_clt_state_lock(); \ >> + for ((it)->i = 0; ((path) = ((it)->next_path)(it)) && \ >> + (it)->i < (it)->clt->paths_num; \ >> + (it)->i++) >> + >> +#define while_each_path(it) \ >> + path_it_deinit(it); \ >> + ibtrs_clt_state_unlock(); \ >> + } >> + >> +/** >> + * get_next_path_rr() - Returns path in round-robin fashion. >> + * >> + * Related to @MP_POLICY_RR >> + * >> + * Locks: >> + * ibtrs_clt_state_lock() must be hold. >> + */ >> +static struct ibtrs_clt_sess *get_next_path_rr(struct path_it *it) >> +{ >> + struct ibtrs_clt_sess __percpu * __rcu *ppcpu_path, *path; >> + struct ibtrs_clt *clt = it->clt; >> + >> + ppcpu_path = this_cpu_ptr(clt->pcpu_path); >> + path = rcu_dereference(*ppcpu_path); >> + if (unlikely(!path)) >> + path = list_first_or_null_rcu(&clt->paths_list, >> + typeof(*path), s.entry); >> + else >> + path = list_next_or_null_rcu_rr(path, &clt->paths_list, >> + s.entry); >> + rcu_assign_pointer(*ppcpu_path, path); >> + >> + return path; >> +} >> + >> +/** >> + * get_next_path_min_inflight() - Returns path with minimal inflight >> count. >> + * >> + * Related to @MP_POLICY_MIN_INFLIGHT >> + * >> + * Locks: >> + * ibtrs_clt_state_lock() must be hold. >> + */ >> +static struct ibtrs_clt_sess *get_next_path_min_inflight(struct path_it >> *it) >> +{ >> + struct ibtrs_clt_sess *min_path = NULL; >> + struct ibtrs_clt *clt = it->clt; >> + struct ibtrs_clt_sess *sess; >> + int min_inflight = INT_MAX; >> + int inflight; >> + >> + list_for_each_entry_rcu(sess, &clt->paths_list, s.entry) { >> + if >> (unlikely(!list_empty(raw_cpu_ptr(sess->mp_skip_entry)))) >> + continue; >> + >> + inflight = atomic_read(&sess->stats.inflight); >> + >> + if (inflight < min_inflight) { >> + min_inflight = inflight; >> + min_path = sess; >> + } >> + } >> + >> + /* >> + * add the path to the skip list, so that next time we can get >> + * a different one >> + */ >> + if (min_path) >> + list_add(raw_cpu_ptr(min_path->mp_skip_entry), >> &it->skip_list); >> + >> + return min_path; >> +} >> + >> +static inline void path_it_init(struct path_it *it, struct ibtrs_clt >> *clt) >> +{ >> + INIT_LIST_HEAD(&it->skip_list); >> + it->clt = clt; >> + it->i = 0; >> + >> + if (clt->mp_policy == MP_POLICY_RR) >> + it->next_path = get_next_path_rr; >> + else >> + it->next_path = get_next_path_min_inflight; >> +} >> + >> +static inline void path_it_deinit(struct path_it *it) >> +{ >> + struct list_head *skip, *tmp; >> + /* >> + * The skip_list is used only for the MIN_INFLIGHT policy. >> + * We need to remove paths from it, so that next IO can insert >> + * paths (->mp_skip_entry) into a skip_list again. >> + */ >> + list_for_each_safe(skip, tmp, &it->skip_list) >> + list_del_init(skip); >> +} >> + >> +static inline void ibtrs_clt_init_req(struct ibtrs_clt_io_req *req, >> + struct ibtrs_clt_sess *sess, >> + ibtrs_conf_fn *conf, >> + struct ibtrs_tag *tag, void *priv, >> + const struct kvec *vec, size_t >> usr_len, >> + struct scatterlist *sg, size_t >> sg_cnt, >> + size_t data_len, int dir) >> +{ >> + req->tag = tag; >> + req->in_use = true; >> + req->usr_len = usr_len; >> + req->data_len = data_len; >> + req->sglist = sg; >> + req->sg_cnt = sg_cnt; >> + req->priv = priv; >> + req->dir = dir; >> + req->con = ibtrs_tag_to_clt_con(sess, tag); >> + req->conf = conf; >> + copy_from_kvec(req->iu->buf, vec, usr_len); >> + if (sess->stats.enable_rdma_lat) >> + req->start_time = ibtrs_clt_get_raw_ms(); >> +} >> + >> +static inline struct ibtrs_clt_io_req * >> +ibtrs_clt_get_req(struct ibtrs_clt_sess *sess, ibtrs_conf_fn *conf, >> + struct ibtrs_tag *tag, void *priv, >> + const struct kvec *vec, size_t usr_len, >> + struct scatterlist *sg, size_t sg_cnt, >> + size_t data_len, int dir) >> +{ >> + struct ibtrs_clt_io_req *req; >> + >> + req = &sess->reqs[tag->mem_id]; >> + ibtrs_clt_init_req(req, sess, conf, tag, priv, vec, usr_len, >> + sg, sg_cnt, data_len, dir); >> + return req; >> +} >> + >> +static inline struct ibtrs_clt_io_req * >> +ibtrs_clt_get_copy_req(struct ibtrs_clt_sess *alive_sess, >> + struct ibtrs_clt_io_req *fail_req) >> +{ >> + struct ibtrs_clt_io_req *req; >> + struct kvec vec = { >> + .iov_base = fail_req->iu->buf, >> + .iov_len = fail_req->usr_len >> + }; >> + >> + req = &alive_sess->reqs[fail_req->tag->mem_id]; >> + ibtrs_clt_init_req(req, alive_sess, fail_req->conf, fail_req->tag, >> + fail_req->priv, &vec, fail_req->usr_len, >> + fail_req->sglist, fail_req->sg_cnt, >> + fail_req->data_len, fail_req->dir); >> + return req; >> +} >> + >> +static int ibtrs_clt_write_req(struct ibtrs_clt_io_req *req); >> +static int ibtrs_clt_read_req(struct ibtrs_clt_io_req *req); >> + >> +static int ibtrs_clt_failover_req(struct ibtrs_clt *clt, >> + struct ibtrs_clt_io_req *fail_req) >> +{ >> + struct ibtrs_clt_sess *alive_sess; >> + struct ibtrs_clt_io_req *req; >> + int err = -ECONNABORTED; >> + struct path_it it; >> + >> + do_each_path(alive_sess, clt, &it) { >> + if (unlikely(alive_sess->state != IBTRS_CLT_CONNECTED)) >> + continue; >> + req = ibtrs_clt_get_copy_req(alive_sess, fail_req); >> + if (req->dir == DMA_TO_DEVICE) >> + err = ibtrs_clt_write_req(req); >> + else >> + err = ibtrs_clt_read_req(req); >> + if (unlikely(err)) { >> + req->in_use = false; >> + continue; >> + } >> + /* Success path */ >> + ibtrs_clt_inc_failover_cnt(&alive_sess->stats); >> + break; >> + } while_each_path(&it); >> + >> + return err; >> +} >> + >> +static void fail_all_outstanding_reqs(struct ibtrs_clt_sess *sess, >> + bool failover) >> +{ >> + struct ibtrs_clt *clt = sess->clt; >> + struct ibtrs_clt_io_req *req; >> + int i; >> + >> + if (!sess->reqs) >> + return; >> + for (i = 0; i < sess->queue_depth; ++i) { >> + bool notify; >> + int err = 0; >> + >> + req = &sess->reqs[i]; >> + if (!req->in_use) >> + continue; >> + >> + if (failover) >> + err = ibtrs_clt_failover_req(clt, req); >> + >> + notify = (!failover || err); >> + complete_rdma_req(req, -ECONNABORTED, notify); >> + } >> +} >> + >> +static void free_sess_reqs(struct ibtrs_clt_sess *sess) >> +{ >> + struct ibtrs_clt_io_req *req; >> + int i; >> + >> + if (!sess->reqs) >> + return; >> + for (i = 0; i < sess->queue_depth; ++i) { >> + req = &sess->reqs[i]; >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) >> + kfree(req->fr_list); >> + else if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) >> + kfree(req->fmr_list); >> + kfree(req->map_page); >> + ibtrs_iu_free(req->iu, DMA_TO_DEVICE, >> + sess->s.ib_dev->dev); >> + } >> + kfree(sess->reqs); >> + sess->reqs = NULL; >> +} >> + >> +static int alloc_sess_reqs(struct ibtrs_clt_sess *sess) >> +{ >> + struct ibtrs_clt_io_req *req; >> + void *mr_list; >> + int i; >> + >> + sess->reqs = kcalloc(sess->queue_depth, sizeof(*sess->reqs), >> + GFP_KERNEL); >> + if (unlikely(!sess->reqs)) >> + return -ENOMEM; >> + >> + for (i = 0; i < sess->queue_depth; ++i) { >> + req = &sess->reqs[i]; >> + req->iu = ibtrs_iu_alloc(i, sess->max_req_size, >> GFP_KERNEL, >> + sess->s.ib_dev->dev, >> DMA_TO_DEVICE, >> + ibtrs_clt_rdma_done); >> + if (unlikely(!req->iu)) >> + goto out; >> + mr_list = kmalloc_array(sess->max_pages_per_mr, >> + sizeof(void *), GFP_KERNEL); >> + if (unlikely(!mr_list)) >> + goto out; >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) >> + req->fr_list = mr_list; >> + else if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) >> + req->fmr_list = mr_list; >> + >> + req->map_page = kmalloc_array(sess->max_pages_per_mr, >> + sizeof(void *), GFP_KERNEL); >> + if (unlikely(!req->map_page)) >> + goto out; >> + } >> + >> + return 0; >> + >> +out: >> + free_sess_reqs(sess); >> + >> + return -ENOMEM; >> +} >> + >> +static int alloc_tags(struct ibtrs_clt *clt) >> +{ >> + unsigned int chunk_bits; >> + int err, i; >> + >> + clt->tags_map = kcalloc(BITS_TO_LONGS(clt->queue_depth), >> sizeof(long), >> + GFP_KERNEL); >> + if (unlikely(!clt->tags_map)) { >> + err = -ENOMEM; >> + goto out_err; >> + } >> + clt->tags = kcalloc(clt->queue_depth, TAG_SIZE(clt), GFP_KERNEL); >> + if (unlikely(!clt->tags)) { >> + err = -ENOMEM; >> + goto err_map; >> + } >> + chunk_bits = ilog2(clt->queue_depth - 1) + 1; >> + for (i = 0; i < clt->queue_depth; i++) { >> + struct ibtrs_tag *tag; >> + >> + tag = GET_TAG(clt, i); >> + tag->mem_id = i; >> + tag->mem_off = i << (MAX_IMM_PAYL_BITS - chunk_bits); >> + } >> + >> + return 0; >> + >> +err_map: >> + kfree(clt->tags_map); >> + clt->tags_map = NULL; >> +out_err: >> + return err; >> +} >> + >> +static void free_tags(struct ibtrs_clt *clt) >> +{ >> + kfree(clt->tags_map); >> + clt->tags_map = NULL; >> + kfree(clt->tags); >> + clt->tags = NULL; >> +} >> + >> +static void query_fast_reg_mode(struct ibtrs_clt_sess *sess) >> +{ >> + struct ibtrs_ib_dev *ib_dev; >> + u64 max_pages_per_mr; >> + int mr_page_shift; >> + >> + ib_dev = sess->s.ib_dev; >> + if (ib_dev->dev->alloc_fmr && ib_dev->dev->dealloc_fmr && >> + ib_dev->dev->map_phys_fmr && ib_dev->dev->unmap_fmr) { >> + sess->fast_reg_mode = IBTRS_FAST_MEM_FMR; >> + ibtrs_info(sess, "Device %s supports FMR\n", >> ib_dev->dev->name); >> + } >> + if (ib_dev->attrs.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS >> && >> + use_fr) { >> + sess->fast_reg_mode = IBTRS_FAST_MEM_FR; >> + ibtrs_info(sess, "Device %s supports FR\n", >> ib_dev->dev->name); >> + } >> + >> + /* >> + * Use the smallest page size supported by the HCA, down to a >> + * minimum of 4096 bytes. We're unlikely to build large sglists >> + * out of smaller entries. >> + */ >> + mr_page_shift = max(12, ffs(ib_dev->attrs.page_size_cap) - >> 1); >> + sess->mr_page_size = 1 << mr_page_shift; >> + sess->max_sge = ib_dev->attrs.max_sge; >> + sess->mr_page_mask = ~((u64)sess->mr_page_size - 1); >> + max_pages_per_mr = ib_dev->attrs.max_mr_size; >> + do_div(max_pages_per_mr, sess->mr_page_size); >> + sess->max_pages_per_mr = min_t(u64, sess->max_pages_per_mr, >> + max_pages_per_mr); >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) { >> + sess->max_pages_per_mr = >> + min_t(u32, sess->max_pages_per_mr, >> + ib_dev->attrs.max_fast_reg_page_list_len); >> + } >> + sess->mr_max_size = sess->mr_page_size * sess->max_pages_per_mr; >> +} >> + >> +static int alloc_con_fast_pool(struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ibtrs_fr_pool *fr_pool; >> + int err = 0; >> + >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) { >> + fr_pool = ibtrs_create_fr_pool(sess->s.ib_dev->dev, >> + sess->s.ib_dev->pd, >> + sess->queue_depth, >> + sess->max_pages_per_mr); >> + if (unlikely(IS_ERR(fr_pool))) { >> + err = PTR_ERR(fr_pool); >> + ibtrs_err(sess, "FR pool allocation failed, err: >> %d\n", >> + err); >> + return err; >> + } >> + con->fr_pool = fr_pool; >> + } >> + >> + return err; >> +} >> + >> +static void free_con_fast_pool(struct ibtrs_clt_con *con) >> +{ >> + if (con->fr_pool) { >> + ibtrs_destroy_fr_pool(con->fr_pool); >> + con->fr_pool = NULL; >> + } >> +} >> + >> +static int alloc_sess_fast_pool(struct ibtrs_clt_sess *sess) >> +{ >> + struct ib_fmr_pool_param fmr_param; >> + struct ib_fmr_pool *fmr_pool; >> + int err = 0; >> + >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) { >> + memset(&fmr_param, 0, sizeof(fmr_param)); >> + fmr_param.pool_size = sess->queue_depth * >> + sess->max_pages_per_mr; >> + fmr_param.dirty_watermark = fmr_param.pool_size / 4; >> + fmr_param.cache = 0; >> + fmr_param.max_pages_per_fmr = sess->max_pages_per_mr; >> + fmr_param.page_shift = ilog2(sess->mr_page_size); >> + fmr_param.access = (IB_ACCESS_LOCAL_WRITE | >> + IB_ACCESS_REMOTE_WRITE); >> + >> + fmr_pool = ib_create_fmr_pool(sess->s.ib_dev->pd, >> &fmr_param); >> + if (unlikely(IS_ERR(fmr_pool))) { >> + err = PTR_ERR(fmr_pool); >> + ibtrs_err(sess, "FMR pool allocation failed, err: >> %d\n", >> + err); >> + return err; >> + } >> + sess->fmr_pool = fmr_pool; >> + } >> + >> + return err; >> +} >> + >> +static void free_sess_fast_pool(struct ibtrs_clt_sess *sess) >> +{ >> + if (sess->fmr_pool) { >> + ib_destroy_fmr_pool(sess->fmr_pool); >> + sess->fmr_pool = NULL; >> + } >> +} >> + >> +static int alloc_sess_io_bufs(struct ibtrs_clt_sess *sess) >> +{ >> + int ret; >> + >> + ret = alloc_sess_reqs(sess); >> + if (unlikely(ret)) { >> + ibtrs_err(sess, "alloc_sess_reqs(), err: %d\n", ret); >> + return ret; >> + } >> + ret = alloc_sess_fast_pool(sess); >> + if (unlikely(ret)) { >> + ibtrs_err(sess, "alloc_sess_fast_pool(), err: %d\n", ret); >> + goto free_reqs; >> + } >> + >> + return 0; >> + >> +free_reqs: >> + free_sess_reqs(sess); >> + >> + return ret; >> +} >> + >> +static void free_sess_io_bufs(struct ibtrs_clt_sess *sess) >> +{ >> + free_sess_reqs(sess); >> + free_sess_fast_pool(sess); >> +} >> + >> +static bool __ibtrs_clt_change_state(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state new_state) >> +{ >> + enum ibtrs_clt_state old_state; >> + bool changed = false; >> + >> + old_state = sess->state; >> + switch (new_state) { >> + case IBTRS_CLT_CONNECTING: >> + switch (old_state) { >> + case IBTRS_CLT_RECONNECTING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_RECONNECTING: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTED: >> + case IBTRS_CLT_CONNECTING_ERR: >> + case IBTRS_CLT_CLOSED: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CONNECTED: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CONNECTING_ERR: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CLOSING: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTING: >> + case IBTRS_CLT_CONNECTING_ERR: >> + case IBTRS_CLT_RECONNECTING: >> + case IBTRS_CLT_CONNECTED: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CLOSED: >> + switch (old_state) { >> + case IBTRS_CLT_CLOSING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_DEAD: >> + switch (old_state) { >> + case IBTRS_CLT_CLOSED: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + default: >> + break; >> + } >> + if (changed) { >> + sess->state = new_state; >> + wake_up_locked(&sess->state_wq); >> + } >> + >> + return changed; >> +} >> + >> +static bool ibtrs_clt_change_state_from_to(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state old_state, >> + enum ibtrs_clt_state new_state) >> +{ >> + bool changed = false; >> + >> + spin_lock_irq(&sess->state_wq.lock); >> + if (sess->state == old_state) >> + changed = __ibtrs_clt_change_state(sess, new_state); >> + spin_unlock_irq(&sess->state_wq.lock); >> + >> + return changed; >> +} >> + >> +static bool ibtrs_clt_change_state_get_old(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state new_state, >> + enum ibtrs_clt_state >> *old_state) >> +{ >> + bool changed; >> + >> + spin_lock_irq(&sess->state_wq.lock); >> + *old_state = sess->state; >> + changed = __ibtrs_clt_change_state(sess, new_state); >> + spin_unlock_irq(&sess->state_wq.lock); >> + >> + return changed; >> +} >> + >> +static bool ibtrs_clt_change_state(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state new_state) >> +{ >> + enum ibtrs_clt_state old_state; >> + >> + return ibtrs_clt_change_state_get_old(sess, new_state, >> &old_state); >> +} >> + >> +static enum ibtrs_clt_state ibtrs_clt_state(struct ibtrs_clt_sess *sess) >> +{ >> + enum ibtrs_clt_state state; >> + >> + spin_lock_irq(&sess->state_wq.lock); >> + state = sess->state; >> + spin_unlock_irq(&sess->state_wq.lock); >> + >> + return state; >> +} >> + >> +static void ibtrs_clt_hb_err_handler(struct ibtrs_con *c, int err) >> +{ >> + struct ibtrs_clt_con *con; >> + >> + (void)err; >> + con = container_of(c, typeof(*con), c); >> + ibtrs_rdma_error_recovery(con); >> +} >> + >> +static void ibtrs_clt_init_hb(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_init_hb(&sess->s, &io_comp_cqe, >> + IBTRS_HB_INTERVAL_MS, >> + IBTRS_HB_MISSED_MAX, >> + ibtrs_clt_hb_err_handler, >> + ibtrs_wq); >> +} >> + >> +static void ibtrs_clt_start_hb(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_start_hb(&sess->s); >> +} >> + >> +static void ibtrs_clt_stop_hb(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_stop_hb(&sess->s); >> +} >> + >> +static void ibtrs_clt_reconnect_work(struct work_struct *work); >> +static void ibtrs_clt_close_work(struct work_struct *work); >> + >> +static struct ibtrs_clt_sess *alloc_sess(struct ibtrs_clt *clt, >> + const struct ibtrs_addr *path, >> + size_t con_num, u16 max_segments) >> +{ >> + struct ibtrs_clt_sess *sess; >> + int err = -ENOMEM; >> + int cpu; >> + >> + sess = kzalloc(sizeof(*sess), GFP_KERNEL); >> + if (unlikely(!sess)) >> + goto err; >> + >> + /* Extra connection for user messages */ >> + con_num += 1; >> + >> + sess->s.con = kcalloc(con_num, sizeof(*sess->s.con), GFP_KERNEL); >> + if (unlikely(!sess->s.con)) >> + goto err_free_sess; >> + >> + mutex_init(&sess->init_mutex); >> + uuid_gen(&sess->s.uuid); >> + memcpy(&sess->s.dst_addr, path->dst, >> + rdma_addr_size((struct sockaddr *)path->dst)); >> + >> + /* >> + * rdma_resolve_addr() passes src_addr to cma_bind_addr, which >> + * checks the sa_family to be non-zero. If user passed >> src_addr=NULL >> + * the sess->src_addr will contain only zeros, which is then fine. >> + */ >> + if (path->src) >> + memcpy(&sess->s.src_addr, path->src, >> + rdma_addr_size((struct sockaddr *)path->src)); >> + strlcpy(sess->s.sessname, clt->sessname, >> sizeof(sess->s.sessname)); >> + sess->s.con_num = con_num; >> + sess->clt = clt; >> + sess->max_pages_per_mr = max_segments; >> + init_waitqueue_head(&sess->state_wq); >> + sess->state = IBTRS_CLT_CONNECTING; >> + atomic_set(&sess->connected_cnt, 0); >> + INIT_WORK(&sess->close_work, ibtrs_clt_close_work); >> + INIT_DELAYED_WORK(&sess->reconnect_dwork, >> ibtrs_clt_reconnect_work); >> + ibtrs_clt_init_hb(sess); >> + >> + sess->mp_skip_entry = alloc_percpu(typeof(*sess->mp_skip_entry)); >> + if (unlikely(!sess->mp_skip_entry)) >> + goto err_free_con; >> + >> + for_each_possible_cpu(cpu) >> + INIT_LIST_HEAD(per_cpu_ptr(sess->mp_skip_entry, cpu)); >> + >> + err = ibtrs_clt_init_stats(&sess->stats); >> + if (unlikely(err)) >> + goto err_free_percpu; >> + >> + return sess; >> + >> +err_free_percpu: >> + free_percpu(sess->mp_skip_entry); >> +err_free_con: >> + kfree(sess->s.con); >> +err_free_sess: >> + kfree(sess); >> +err: >> + return ERR_PTR(err); >> +} >> + >> +static void free_sess(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_clt_free_stats(&sess->stats); >> + free_percpu(sess->mp_skip_entry); >> + kfree(sess->s.con); >> + kfree(sess->srv_rdma_addr); >> + kfree(sess); >> +} >> + >> +static int create_con(struct ibtrs_clt_sess *sess, unsigned int cid) >> +{ >> + struct ibtrs_clt_con *con; >> + >> + con = kzalloc(sizeof(*con), GFP_KERNEL); >> + if (unlikely(!con)) >> + return -ENOMEM; >> + >> + /* Map first two connections to the first CPU */ >> + con->cpu = (cid ? cid - 1 : 0) % nr_cpu_ids; >> + con->c.cid = cid; >> + con->c.sess = &sess->s; >> + atomic_set(&con->io_cnt, 0); >> + >> + sess->s.con[cid] = &con->c; >> + >> + return 0; >> +} >> + >> +static void destroy_con(struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + >> + sess->s.con[con->c.cid] = NULL; >> + kfree(con); >> +} >> + >> +static int create_con_cq_qp(struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + u16 cq_size, wr_queue_size; >> + int err, cq_vector; >> + >> + /* >> + * This function can fail, but still destroy_con_cq_qp() should >> + * be called, this is because create_con_cq_qp() is called on cm >> + * event path, thus caller/waiter never knows: have we failed >> before >> + * create_con_cq_qp() or after. To solve this dilemma without >> + * creating any additional flags just allow destroy_con_cq_qp() be >> + * called many times. >> + */ >> + >> + if (con->c.cid == 0) { >> + cq_size = SERVICE_CON_QUEUE_DEPTH; >> + /* + 2 for drain and heartbeat */ >> + wr_queue_size = SERVICE_CON_QUEUE_DEPTH + 2; >> + /* We must be the first here */ >> + if (WARN_ON(sess->s.ib_dev)) >> + return -EINVAL; >> + >> + /* >> + * The whole session uses device from user connection. >> + * Be careful not to close user connection before ib dev >> + * is gracefully put. >> + */ >> + sess->s.ib_dev = ibtrs_ib_dev_find_get(con->c.cm_id); >> + if (unlikely(!sess->s.ib_dev)) { >> + ibtrs_wrn(sess, "ibtrs_ib_dev_find_get(): no >> memory\n"); >> + return -ENOMEM; >> + } >> + sess->s.ib_dev_ref = 1; >> + query_fast_reg_mode(sess); >> + } else { >> + int num_wr; >> + >> + /* >> + * Here we assume that session members are correctly set. >> + * This is always true if user connection (cid == 0) is >> + * established first. >> + */ >> + if (WARN_ON(!sess->s.ib_dev)) >> + return -EINVAL; >> + if (WARN_ON(!sess->queue_depth)) >> + return -EINVAL; >> + >> + /* Shared between connections */ >> + sess->s.ib_dev_ref++; >> + cq_size = sess->queue_depth; >> + num_wr = DIV_ROUND_UP(sess->max_pages_per_mr, >> sess->max_sge); >> + wr_queue_size = sess->s.ib_dev->attrs.max_qp_wr; >> + wr_queue_size = min_t(int, wr_queue_size, >> + sess->queue_depth * num_wr * >> + (use_fr ? 3 : 2) + 1); >> + } >> + cq_vector = con->cpu % sess->s.ib_dev->dev->num_comp_vectors; >> + err = ibtrs_cq_qp_create(&sess->s, &con->c, sess->max_sge, >> + cq_vector, cq_size, wr_queue_size, >> + IB_POLL_SOFTIRQ); >> + /* >> + * In case of error we do not bother to clean previous >> allocations, >> + * since destroy_con_cq_qp() must be called. >> + */ From mboxrd@z Thu Jan 1 00:00:00 1970 From: Roman Penyaev Subject: Re: [PATCH 05/24] ibtrs: client: main functionality Date: Mon, 5 Feb 2018 15:19:12 +0100 Message-ID: References: <20180202140904.2017-1-roman.penyaev@profitbricks.com> <20180202140904.2017-6-roman.penyaev@profitbricks.com> Mime-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Return-path: In-Reply-To: Sender: linux-rdma-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: Sagi Grimberg Cc: linux-block-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, linux-rdma-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, Jens Axboe , Christoph Hellwig , Bart Van Assche , Or Gerlitz , Danil Kipnis , Jack Wang List-Id: linux-rdma@vger.kernel.org Hi Sagi, On Mon, Feb 5, 2018 at 12:19 PM, Sagi Grimberg wrote: > Hi Roman, > >> +static inline void ibtrs_clt_state_lock(void) >> +{ >> + rcu_read_lock(); >> +} >> + >> +static inline void ibtrs_clt_state_unlock(void) >> +{ >> + rcu_read_unlock(); >> +} > > > This looks rather pointless... Yeah, old scraps. Some time later those were not only wrappers around rcu. Now rcu can be called explicitly, that is true. Thanks. > >> + >> +#define cmpxchg_min(var, new) ({ \ >> + typeof(var) old; \ >> + \ >> + do { \ >> + old = var; \ >> + new = (!old ? new : min_t(typeof(var), old, new)); \ >> + } while (cmpxchg(&var, old, new) != old); \ >> +}) > > > Why is this sort of thing local to your driver? Good question :) Most likely because personally I do not know what is the good generic place for this kind of stuff. Probably I share the same feeling with the author of these lines in nvme/host/rdma.c: put_unaligned_le24() :) >> +/** >> + * struct ibtrs_fr_pool - pool of fast registration descriptors >> + * >> + * An entry is available for allocation if and only if it occurs in >> @free_list. >> + * >> + * @size: Number of descriptors in this pool. >> + * @max_page_list_len: Maximum fast registration work request page list >> length. >> + * @lock: Protects free_list. >> + * @free_list: List of free descriptors. >> + * @desc: Fast registration descriptor pool. >> + */ >> +struct ibtrs_fr_pool { >> + int size; >> + int max_page_list_len; >> + spinlock_t lock; /* protects free_list */ >> + struct list_head free_list; >> + struct ibtrs_fr_desc desc[0]; >> +}; > > > We already have a per-qp fr list implementation, any specific reason to > implement it again? No, fr is a part of the code which we are not using, fmr is faster in our setup. So we will need to reiterate on fr mode, thanks. >> +static inline struct ibtrs_tag * >> +__ibtrs_get_tag(struct ibtrs_clt *clt, enum ibtrs_clt_con_type con_type) >> +{ >> + size_t max_depth = clt->queue_depth; >> + struct ibtrs_tag *tag; >> + int cpu, bit; >> + >> + cpu = get_cpu(); >> + do { >> + bit = find_first_zero_bit(clt->tags_map, max_depth); >> + if (unlikely(bit >= max_depth)) { >> + put_cpu(); >> + return NULL; >> + } >> + >> + } while (unlikely(test_and_set_bit_lock(bit, clt->tags_map))); >> + put_cpu(); >> + >> + tag = GET_TAG(clt, bit); >> + WARN_ON(tag->mem_id != bit); >> + tag->cpu_id = cpu; >> + tag->con_type = con_type; >> + >> + return tag; >> +} >> + >> +static inline void __ibtrs_put_tag(struct ibtrs_clt *clt, >> + struct ibtrs_tag *tag) >> +{ >> + clear_bit_unlock(tag->mem_id, clt->tags_map); >> +} >> + >> +struct ibtrs_tag *ibtrs_clt_get_tag(struct ibtrs_clt *clt, >> + enum ibtrs_clt_con_type con_type, >> + int can_wait) >> +{ >> + struct ibtrs_tag *tag; >> + DEFINE_WAIT(wait); >> + >> + tag = __ibtrs_get_tag(clt, con_type); >> + if (likely(tag) || !can_wait) >> + return tag; >> + >> + do { >> + prepare_to_wait(&clt->tags_wait, &wait, >> TASK_UNINTERRUPTIBLE); >> + tag = __ibtrs_get_tag(clt, con_type); >> + if (likely(tag)) >> + break; >> + >> + io_schedule(); >> + } while (1); >> + >> + finish_wait(&clt->tags_wait, &wait); >> + >> + return tag; >> +} >> +EXPORT_SYMBOL(ibtrs_clt_get_tag); >> + >> +void ibtrs_clt_put_tag(struct ibtrs_clt *clt, struct ibtrs_tag *tag) >> +{ >> + if (WARN_ON(!test_bit(tag->mem_id, clt->tags_map))) >> + return; >> + >> + __ibtrs_put_tag(clt, tag); >> + >> + /* >> + * Putting a tag is a barrier, so we will observe >> + * new entry in the wait list, no worries. >> + */ >> + if (waitqueue_active(&clt->tags_wait)) >> + wake_up(&clt->tags_wait); >> +} >> +EXPORT_SYMBOL(ibtrs_clt_put_tag); > > > Again, the tags are not clear why they are needed... We have two separate instances: block device (IBNBD) and a transport library (IBTRS). Many block devices share the same IBTRS session with fixed size queue depth. Tags is a part of IBTRS, so with allocated tag you get a free slot of a buffer where you can read/write, so once you've allocated a tag you won't sleep on IO path inside a library. Also tag helps a lot on IO fail-over to another connection (multipath implementation, which is also a part of the transport library, not a block device), where you simply reuse the same buffer slot (with a tag in your hands) forwarding IO to another RDMA connection. >> +/** >> + * ibtrs_destroy_fr_pool() - free the resources owned by a pool >> + * @pool: Fast registration pool to be destroyed. >> + */ >> +static void ibtrs_destroy_fr_pool(struct ibtrs_fr_pool *pool) >> +{ >> + struct ibtrs_fr_desc *d; >> + int i, err; >> + >> + if (!pool) >> + return; >> + >> + for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) { >> + if (d->mr) { >> + err = ib_dereg_mr(d->mr); >> + if (err) >> + pr_err("Failed to deregister memory >> region," >> + " err: %d\n", err); >> + } >> + } >> + kfree(pool); >> +} >> + >> +/** >> + * ibtrs_create_fr_pool() - allocate and initialize a pool for fast >> registration >> + * @device: IB device to allocate fast registration >> descriptors for. >> + * @pd: Protection domain associated with the FR >> descriptors. >> + * @pool_size: Number of descriptors to allocate. >> + * @max_page_list_len: Maximum fast registration work request page list >> length. >> + */ >> +static struct ibtrs_fr_pool *ibtrs_create_fr_pool(struct ib_device >> *device, >> + struct ib_pd *pd, >> + int pool_size, >> + int max_page_list_len) >> +{ >> + struct ibtrs_fr_pool *pool; >> + struct ibtrs_fr_desc *d; >> + struct ib_mr *mr; >> + int i, ret; >> + >> + if (pool_size <= 0) { >> + pr_warn("Creating fr pool failed, invalid pool size %d\n", >> + pool_size); >> + ret = -EINVAL; >> + goto err; >> + } >> + >> + pool = kzalloc(sizeof(*pool) + pool_size * sizeof(*d), >> GFP_KERNEL); >> + if (!pool) { >> + ret = -ENOMEM; >> + goto err; >> + } >> + >> + pool->size = pool_size; >> + pool->max_page_list_len = max_page_list_len; >> + spin_lock_init(&pool->lock); >> + INIT_LIST_HEAD(&pool->free_list); >> + >> + for (i = 0, d = &pool->desc[0]; i < pool->size; i++, d++) { >> + mr = ib_alloc_mr(pd, IB_MR_TYPE_MEM_REG, >> max_page_list_len); >> + if (IS_ERR(mr)) { >> + pr_warn("Failed to allocate fast region >> memory\n"); >> + ret = PTR_ERR(mr); >> + goto destroy_pool; >> + } >> + d->mr = mr; >> + list_add_tail(&d->entry, &pool->free_list); >> + } >> + >> + return pool; >> + >> +destroy_pool: >> + ibtrs_destroy_fr_pool(pool); >> +err: >> + return ERR_PTR(ret); >> +} >> + >> +/** >> + * ibtrs_fr_pool_get() - obtain a descriptor suitable for fast >> registration >> + * @pool: Pool to obtain descriptor from. >> + */ >> +static struct ibtrs_fr_desc *ibtrs_fr_pool_get(struct ibtrs_fr_pool >> *pool) >> +{ >> + struct ibtrs_fr_desc *d = NULL; >> + >> + spin_lock_bh(&pool->lock); >> + if (!list_empty(&pool->free_list)) { >> + d = list_first_entry(&pool->free_list, typeof(*d), entry); >> + list_del(&d->entry); >> + } >> + spin_unlock_bh(&pool->lock); >> + >> + return d; >> +} >> + >> +/** >> + * ibtrs_fr_pool_put() - put an FR descriptor back in the free list >> + * @pool: Pool the descriptor was allocated from. >> + * @desc: Pointer to an array of fast registration descriptor pointers. >> + * @n: Number of descriptors to put back. >> + * >> + * Note: The caller must already have queued an invalidation request for >> + * desc->mr->rkey before calling this function. >> + */ >> +static void ibtrs_fr_pool_put(struct ibtrs_fr_pool *pool, >> + struct ibtrs_fr_desc **desc, int n) >> +{ >> + int i; >> + >> + spin_lock_bh(&pool->lock); >> + for (i = 0; i < n; i++) >> + list_add(&desc[i]->entry, &pool->free_list); >> + spin_unlock_bh(&pool->lock); >> +} >> + >> +static void ibtrs_map_desc(struct ibtrs_map_state *state, dma_addr_t >> dma_addr, >> + u32 dma_len, u32 rkey, u32 max_desc) >> +{ >> + struct ibtrs_sg_desc *desc = state->desc; >> + >> + pr_debug("dma_addr %llu, key %u, dma_len %u\n", >> + dma_addr, rkey, dma_len); >> + desc->addr = cpu_to_le64(dma_addr); >> + desc->key = cpu_to_le32(rkey); >> + desc->len = cpu_to_le32(dma_len); >> + >> + state->total_len += dma_len; >> + if (state->ndesc < max_desc) { >> + state->desc++; >> + state->ndesc++; >> + } else { >> + state->ndesc = INT_MIN; >> + pr_err("Could not fit S/G list into buffer descriptor >> %d.\n", >> + max_desc); >> + } >> +} >> + >> +static int ibtrs_map_finish_fmr(struct ibtrs_map_state *state, >> + struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ib_pool_fmr *fmr; >> + dma_addr_t dma_addr; >> + u64 io_addr = 0; >> + >> + fmr = ib_fmr_pool_map_phys(sess->fmr_pool, state->pages, >> + state->npages, io_addr); >> + if (IS_ERR(fmr)) { >> + ibtrs_wrn_rl(sess, "Failed to map FMR from FMR pool, " >> + "err: %ld\n", PTR_ERR(fmr)); >> + return PTR_ERR(fmr); >> + } >> + >> + *state->next_fmr++ = fmr; >> + state->nmdesc++; >> + dma_addr = state->base_dma_addr & ~sess->mr_page_mask; >> + pr_debug("ndesc = %d, nmdesc = %d, npages = %d\n", >> + state->ndesc, state->nmdesc, state->npages); >> + if (state->dir == DMA_TO_DEVICE) >> + ibtrs_map_desc(state, dma_addr, state->dma_len, >> fmr->fmr->lkey, >> + sess->max_desc); >> + else >> + ibtrs_map_desc(state, dma_addr, state->dma_len, >> fmr->fmr->rkey, >> + sess->max_desc); >> + >> + return 0; >> +} >> + >> +static void ibtrs_clt_fast_reg_done(struct ib_cq *cq, struct ib_wc *wc) >> +{ >> + struct ibtrs_clt_con *con = cq->cq_context; >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + >> + if (unlikely(wc->status != IB_WC_SUCCESS)) { >> + ibtrs_err(sess, "Failed IB_WR_REG_MR: %s\n", >> + ib_wc_status_msg(wc->status)); >> + ibtrs_rdma_error_recovery(con); >> + } >> +} >> + >> +static struct ib_cqe fast_reg_cqe = { >> + .done = ibtrs_clt_fast_reg_done >> +}; >> + >> +/* TODO */ >> +static int ibtrs_map_finish_fr(struct ibtrs_map_state *state, >> + struct ibtrs_clt_con *con, int sg_cnt, >> + unsigned int *sg_offset_p) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ibtrs_fr_desc *desc; >> + struct ib_send_wr *bad_wr; >> + struct ib_reg_wr wr; >> + struct ib_pd *pd; >> + u32 rkey; >> + int n; >> + >> + pd = sess->s.ib_dev->pd; >> + if (sg_cnt == 1 && (pd->flags & IB_PD_UNSAFE_GLOBAL_RKEY)) { >> + unsigned int sg_offset = sg_offset_p ? *sg_offset_p : 0; >> + >> + ibtrs_map_desc(state, sg_dma_address(state->sg) + >> sg_offset, >> + sg_dma_len(state->sg) - sg_offset, >> + pd->unsafe_global_rkey, sess->max_desc); >> + if (sg_offset_p) >> + *sg_offset_p = 0; >> + return 1; >> + } >> + >> + desc = ibtrs_fr_pool_get(con->fr_pool); >> + if (!desc) { >> + ibtrs_wrn_rl(sess, "Failed to get descriptor from FR >> pool\n"); >> + return -ENOMEM; >> + } >> + >> + rkey = ib_inc_rkey(desc->mr->rkey); >> + ib_update_fast_reg_key(desc->mr, rkey); >> + >> + memset(&wr, 0, sizeof(wr)); >> + n = ib_map_mr_sg(desc->mr, state->sg, sg_cnt, sg_offset_p, >> + sess->mr_page_size); >> + if (unlikely(n < 0)) { >> + ibtrs_fr_pool_put(con->fr_pool, &desc, 1); >> + return n; >> + } >> + >> + wr.wr.next = NULL; >> + wr.wr.opcode = IB_WR_REG_MR; >> + wr.wr.wr_cqe = &fast_reg_cqe; >> + wr.wr.num_sge = 0; >> + wr.wr.send_flags = 0; >> + wr.mr = desc->mr; >> + wr.key = desc->mr->rkey; >> + wr.access = (IB_ACCESS_LOCAL_WRITE | IB_ACCESS_REMOTE_WRITE); > > > Do you actually ever have remote write access in your protocol? We do not have reads, instead client writes on write and server writes on read. (write only storage solution :) > >> +static void ibtrs_clt_inv_rkey_done(struct ib_cq *cq, struct ib_wc *wc) >> +{ >> + struct ibtrs_clt_con *con = cq->cq_context; >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + >> + if (unlikely(wc->status != IB_WC_SUCCESS)) { >> + ibtrs_err(sess, "Failed IB_WR_LOCAL_INV: %s\n", >> + ib_wc_status_msg(wc->status)); >> + ibtrs_rdma_error_recovery(con); >> + } >> +} >> + >> +static struct ib_cqe local_inv_cqe = { >> + .done = ibtrs_clt_inv_rkey_done >> +}; >> + >> +static int ibtrs_inv_rkey(struct ibtrs_clt_con *con, u32 rkey) >> +{ >> + struct ib_send_wr *bad_wr; >> + struct ib_send_wr wr = { >> + .opcode = IB_WR_LOCAL_INV, >> + .wr_cqe = &local_inv_cqe, >> + .next = NULL, >> + .num_sge = 0, >> + .send_flags = 0, >> + .ex.invalidate_rkey = rkey, >> + }; >> + >> + return ib_post_send(con->c.qp, &wr, &bad_wr); >> +} > > > Is not signalling the local invalidate safe? A recent report > suggested that this is not safe in the presence of ack drops. For our setup we use fmr, so frankly I do not follow any fr discussions. Could you please provide the link? >> +static int ibtrs_post_send_rdma(struct ibtrs_clt_con *con, >> + struct ibtrs_clt_io_req *req, >> + u64 addr, u32 off, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + enum ib_send_flags flags; >> + struct ib_sge list[1]; >> + >> + if (unlikely(!req->sg_size)) { >> + ibtrs_wrn(sess, "Doing RDMA Write failed, no data >> supplied\n"); >> + return -EINVAL; >> + } >> + >> + /* user data and user message in the first list element */ >> + list[0].addr = req->iu->dma_addr; >> + list[0].length = req->sg_size; >> + list[0].lkey = sess->s.ib_dev->lkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + return ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, 1, >> + sess->srv_rdma_buf_rkey, >> + addr + off, imm, flags); >> +} >> + >> +static void ibtrs_set_sge_with_desc(struct ib_sge *list, >> + struct ibtrs_sg_desc *desc) >> +{ >> + list->addr = le64_to_cpu(desc->addr); >> + list->length = le32_to_cpu(desc->len); >> + list->lkey = le32_to_cpu(desc->key); >> + pr_debug("dma_addr %llu, key %u, dma_len %u\n", >> + list->addr, list->lkey, list->length); >> +} >> + >> +static void ibtrs_set_rdma_desc_last(struct ibtrs_clt_con *con, >> + struct ib_sge *list, >> + struct ibtrs_clt_io_req *req, >> + struct ib_rdma_wr *wr, int offset, >> + struct ibtrs_sg_desc *desc, int m, >> + int n, u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + enum ib_send_flags flags; >> + int i; >> + >> + for (i = m; i < n; i++, desc++) >> + ibtrs_set_sge_with_desc(&list[i], desc); >> + >> + list[i].addr = req->iu->dma_addr; >> + list[i].length = size; >> + list[i].lkey = sess->s.ib_dev->lkey; >> + >> + wr->wr.wr_cqe = &req->iu->cqe; >> + wr->wr.sg_list = &list[m]; >> + wr->wr.num_sge = n - m + 1; >> + wr->remote_addr = addr + offset; >> + wr->rkey = sess->srv_rdma_buf_rkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + >> + wr->wr.opcode = IB_WR_RDMA_WRITE_WITH_IMM; >> + wr->wr.send_flags = flags; >> + wr->wr.ex.imm_data = cpu_to_be32(imm); >> +} >> + >> +static int ibtrs_post_send_rdma_desc_more(struct ibtrs_clt_con *con, >> + struct ib_sge *list, >> + struct ibtrs_clt_io_req *req, >> + struct ibtrs_sg_desc *desc, int >> n, >> + u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + size_t max_sge, num_sge, num_wr; >> + struct ib_send_wr *bad_wr; >> + struct ib_rdma_wr *wrs, *wr; >> + int j = 0, k, offset = 0, len = 0; >> + int m = 0; >> + int ret; >> + >> + max_sge = sess->max_sge; >> + num_sge = 1 + n; >> + num_wr = DIV_ROUND_UP(num_sge, max_sge); >> + >> + wrs = kcalloc(num_wr, sizeof(*wrs), GFP_ATOMIC); >> + if (!wrs) >> + return -ENOMEM; >> + >> + if (num_wr == 1) >> + goto last_one; >> + >> + for (; j < num_wr; j++) { >> + wr = &wrs[j]; >> + for (k = 0; k < max_sge; k++, desc++) { >> + m = k + j * max_sge; >> + ibtrs_set_sge_with_desc(&list[m], desc); >> + len += le32_to_cpu(desc->len); >> + } >> + wr->wr.wr_cqe = &req->iu->cqe; >> + wr->wr.sg_list = &list[m]; >> + wr->wr.num_sge = max_sge; >> + wr->remote_addr = addr + offset; >> + wr->rkey = sess->srv_rdma_buf_rkey; >> + >> + offset += len; >> + wr->wr.next = &wrs[j + 1].wr; >> + wr->wr.opcode = IB_WR_RDMA_WRITE; >> + } >> + >> +last_one: >> + wr = &wrs[j]; >> + >> + ibtrs_set_rdma_desc_last(con, list, req, wr, offset, >> + desc, m, n, addr, size, imm); >> + >> + ret = ib_post_send(con->c.qp, &wrs[0].wr, &bad_wr); >> + if (unlikely(ret)) >> + ibtrs_err(sess, "Posting write request to QP failed," >> + " err: %d\n", ret); >> + kfree(wrs); >> + return ret; >> +} >> + >> +static int ibtrs_post_send_rdma_desc(struct ibtrs_clt_con *con, >> + struct ibtrs_clt_io_req *req, >> + struct ibtrs_sg_desc *desc, int n, >> + u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + enum ib_send_flags flags; >> + struct ib_sge *list; >> + size_t num_sge; >> + int ret, i; >> + >> + num_sge = 1 + n; >> + list = kmalloc_array(num_sge, sizeof(*list), GFP_ATOMIC); >> + if (!list) >> + return -ENOMEM; >> + >> + if (num_sge < sess->max_sge) { >> + for (i = 0; i < n; i++, desc++) >> + ibtrs_set_sge_with_desc(&list[i], desc); >> + list[i].addr = req->iu->dma_addr; >> + list[i].length = size; >> + list[i].lkey = sess->s.ib_dev->lkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % >> sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + ret = ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, >> + num_sge, >> + >> sess->srv_rdma_buf_rkey, >> + addr, imm, flags); >> + } else { >> + ret = ibtrs_post_send_rdma_desc_more(con, list, req, desc, >> n, >> + addr, size, imm); >> + } >> + >> + kfree(list); >> + return ret; >> +} >> + >> +static int ibtrs_post_send_rdma_more(struct ibtrs_clt_con *con, >> + struct ibtrs_clt_io_req *req, >> + u64 addr, u32 size, u32 imm) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ib_device *ibdev = sess->s.ib_dev->dev; >> + enum ib_send_flags flags; >> + struct scatterlist *sg; >> + struct ib_sge *list; >> + size_t num_sge; >> + int i, ret; >> + >> + num_sge = 1 + req->sg_cnt; >> + list = kmalloc_array(num_sge, sizeof(*list), GFP_ATOMIC); >> + if (!list) >> + return -ENOMEM; >> + >> + for_each_sg(req->sglist, sg, req->sg_cnt, i) { >> + list[i].addr = ib_sg_dma_address(ibdev, sg); >> + list[i].length = ib_sg_dma_len(ibdev, sg); >> + list[i].lkey = sess->s.ib_dev->lkey; >> + } >> + list[i].addr = req->iu->dma_addr; >> + list[i].length = size; >> + list[i].lkey = sess->s.ib_dev->lkey; >> + >> + /* >> + * From time to time we have to post signalled sends, >> + * or send queue will fill up and only QP reset can help. >> + */ >> + flags = atomic_inc_return(&con->io_cnt) % sess->queue_depth ? >> + 0 : IB_SEND_SIGNALED; >> + ret = ibtrs_iu_post_rdma_write_imm(&con->c, req->iu, list, >> num_sge, >> + sess->srv_rdma_buf_rkey, >> + addr, imm, flags); >> + kfree(list); >> + >> + return ret; >> +} > > > All these rdma halpers looks like that can be reused from the rdma rw > API if it was enhanced with immediate capabilities. True. >> +static inline unsigned long ibtrs_clt_get_raw_ms(void) >> +{ >> + struct timespec ts; >> + >> + getrawmonotonic(&ts); >> + >> + return timespec_to_ns(&ts) / NSEC_PER_MSEC; >> +} > > > Why is this local to your driver? > >> + >> +static void complete_rdma_req(struct ibtrs_clt_io_req *req, >> + int errno, bool notify) >> +{ >> + struct ibtrs_clt_con *con = req->con; >> + struct ibtrs_clt_sess *sess; >> + enum dma_data_direction dir; >> + struct ibtrs_clt *clt; >> + void *priv; >> + >> + if (WARN_ON(!req->in_use)) >> + return; >> + if (WARN_ON(!req->con)) >> + return; >> + sess = to_clt_sess(con->c.sess); >> + clt = sess->clt; >> + >> + if (req->sg_cnt > fmr_sg_cnt) >> + ibtrs_unmap_fast_reg_data(req->con, req); >> + if (req->sg_cnt) >> + ib_dma_unmap_sg(sess->s.ib_dev->dev, req->sglist, >> + req->sg_cnt, req->dir); >> + if (sess->stats.enable_rdma_lat) >> + ibtrs_clt_update_rdma_lat(&sess->stats, >> + req->dir == DMA_FROM_DEVICE, >> + ibtrs_clt_get_raw_ms() - >> + req->start_time); >> + ibtrs_clt_decrease_inflight(&sess->stats); >> + >> + req->in_use = false; >> + req->con = NULL; >> + priv = req->priv; >> + dir = req->dir; >> + >> + if (notify) >> + req->conf(priv, errno); >> +} > > > > >> + >> +static void process_io_rsp(struct ibtrs_clt_sess *sess, u32 msg_id, s16 >> errno) >> +{ >> + if (WARN_ON(msg_id >= sess->queue_depth)) >> + return; >> + >> + complete_rdma_req(&sess->reqs[msg_id], errno, true); >> +} >> + >> +static struct ib_cqe io_comp_cqe = { >> + .done = ibtrs_clt_rdma_done >> +}; >> + >> +static void ibtrs_clt_rdma_done(struct ib_cq *cq, struct ib_wc *wc) >> +{ >> + struct ibtrs_clt_con *con = cq->cq_context; >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + u32 imm_type, imm_payload; >> + int err; >> + >> + if (unlikely(wc->status != IB_WC_SUCCESS)) { >> + if (wc->status != IB_WC_WR_FLUSH_ERR) { >> + ibtrs_err(sess, "RDMA failed: %s\n", >> + ib_wc_status_msg(wc->status)); >> + ibtrs_rdma_error_recovery(con); >> + } >> + return; >> + } >> + ibtrs_clt_update_wc_stats(con); >> + >> + switch (wc->opcode) { >> + case IB_WC_RDMA_WRITE: >> + /* >> + * post_send() RDMA write completions of IO reqs >> (read/write) >> + * and hb >> + */ >> + break; >> + case IB_WC_RECV_RDMA_WITH_IMM: >> + /* >> + * post_recv() RDMA write completions of IO reqs >> (read/write) >> + * and hb >> + */ >> + if (WARN_ON(wc->wr_cqe != &io_comp_cqe)) >> + return; >> + err = ibtrs_post_recv_empty(&con->c, &io_comp_cqe); >> + if (unlikely(err)) { >> + ibtrs_err(sess, "ibtrs_post_recv_empty(): %d\n", >> err); >> + ibtrs_rdma_error_recovery(con); >> + break; >> + } >> + ibtrs_from_imm(be32_to_cpu(wc->ex.imm_data), >> + &imm_type, &imm_payload); >> + if (likely(imm_type == IBTRS_IO_RSP_IMM)) { >> + u32 msg_id; >> + >> + ibtrs_from_io_rsp_imm(imm_payload, &msg_id, &err); >> + process_io_rsp(sess, msg_id, err); >> + } else if (imm_type == IBTRS_HB_MSG_IMM) { >> + WARN_ON(con->c.cid); >> + ibtrs_send_hb_ack(&sess->s); >> + } else if (imm_type == IBTRS_HB_ACK_IMM) { >> + WARN_ON(con->c.cid); >> + sess->s.hb_missed_cnt = 0; >> + } else { >> + ibtrs_wrn(sess, "Unknown IMM type %u\n", >> imm_type); >> + } >> + break; >> + default: >> + ibtrs_wrn(sess, "Unexpected WC type: %s\n", >> + ib_wc_opcode_str(wc->opcode)); >> + return; >> + } > > > Is there a spec somewhere with the protocol information that explains > how this all works? Not yet. The transfer procedure is described in vault presentation. Is README is a good place for such stuff? I mean some low-level protocol spec. >> +struct path_it { >> + int i; >> + struct list_head skip_list; >> + struct ibtrs_clt *clt; >> + struct ibtrs_clt_sess *(*next_path)(struct path_it *); >> +}; >> + >> +#define do_each_path(path, clt, it) { \ >> + path_it_init(it, clt); \ >> + ibtrs_clt_state_lock(); \ >> + for ((it)->i = 0; ((path) = ((it)->next_path)(it)) && \ >> + (it)->i < (it)->clt->paths_num; \ >> + (it)->i++) >> + >> +#define while_each_path(it) \ >> + path_it_deinit(it); \ >> + ibtrs_clt_state_unlock(); \ >> + } >> + >> +/** >> + * get_next_path_rr() - Returns path in round-robin fashion. >> + * >> + * Related to @MP_POLICY_RR >> + * >> + * Locks: >> + * ibtrs_clt_state_lock() must be hold. >> + */ >> +static struct ibtrs_clt_sess *get_next_path_rr(struct path_it *it) >> +{ >> + struct ibtrs_clt_sess __percpu * __rcu *ppcpu_path, *path; >> + struct ibtrs_clt *clt = it->clt; >> + >> + ppcpu_path = this_cpu_ptr(clt->pcpu_path); >> + path = rcu_dereference(*ppcpu_path); >> + if (unlikely(!path)) >> + path = list_first_or_null_rcu(&clt->paths_list, >> + typeof(*path), s.entry); >> + else >> + path = list_next_or_null_rcu_rr(path, &clt->paths_list, >> + s.entry); >> + rcu_assign_pointer(*ppcpu_path, path); >> + >> + return path; >> +} >> + >> +/** >> + * get_next_path_min_inflight() - Returns path with minimal inflight >> count. >> + * >> + * Related to @MP_POLICY_MIN_INFLIGHT >> + * >> + * Locks: >> + * ibtrs_clt_state_lock() must be hold. >> + */ >> +static struct ibtrs_clt_sess *get_next_path_min_inflight(struct path_it >> *it) >> +{ >> + struct ibtrs_clt_sess *min_path = NULL; >> + struct ibtrs_clt *clt = it->clt; >> + struct ibtrs_clt_sess *sess; >> + int min_inflight = INT_MAX; >> + int inflight; >> + >> + list_for_each_entry_rcu(sess, &clt->paths_list, s.entry) { >> + if >> (unlikely(!list_empty(raw_cpu_ptr(sess->mp_skip_entry)))) >> + continue; >> + >> + inflight = atomic_read(&sess->stats.inflight); >> + >> + if (inflight < min_inflight) { >> + min_inflight = inflight; >> + min_path = sess; >> + } >> + } >> + >> + /* >> + * add the path to the skip list, so that next time we can get >> + * a different one >> + */ >> + if (min_path) >> + list_add(raw_cpu_ptr(min_path->mp_skip_entry), >> &it->skip_list); >> + >> + return min_path; >> +} >> + >> +static inline void path_it_init(struct path_it *it, struct ibtrs_clt >> *clt) >> +{ >> + INIT_LIST_HEAD(&it->skip_list); >> + it->clt = clt; >> + it->i = 0; >> + >> + if (clt->mp_policy == MP_POLICY_RR) >> + it->next_path = get_next_path_rr; >> + else >> + it->next_path = get_next_path_min_inflight; >> +} >> + >> +static inline void path_it_deinit(struct path_it *it) >> +{ >> + struct list_head *skip, *tmp; >> + /* >> + * The skip_list is used only for the MIN_INFLIGHT policy. >> + * We need to remove paths from it, so that next IO can insert >> + * paths (->mp_skip_entry) into a skip_list again. >> + */ >> + list_for_each_safe(skip, tmp, &it->skip_list) >> + list_del_init(skip); >> +} >> + >> +static inline void ibtrs_clt_init_req(struct ibtrs_clt_io_req *req, >> + struct ibtrs_clt_sess *sess, >> + ibtrs_conf_fn *conf, >> + struct ibtrs_tag *tag, void *priv, >> + const struct kvec *vec, size_t >> usr_len, >> + struct scatterlist *sg, size_t >> sg_cnt, >> + size_t data_len, int dir) >> +{ >> + req->tag = tag; >> + req->in_use = true; >> + req->usr_len = usr_len; >> + req->data_len = data_len; >> + req->sglist = sg; >> + req->sg_cnt = sg_cnt; >> + req->priv = priv; >> + req->dir = dir; >> + req->con = ibtrs_tag_to_clt_con(sess, tag); >> + req->conf = conf; >> + copy_from_kvec(req->iu->buf, vec, usr_len); >> + if (sess->stats.enable_rdma_lat) >> + req->start_time = ibtrs_clt_get_raw_ms(); >> +} >> + >> +static inline struct ibtrs_clt_io_req * >> +ibtrs_clt_get_req(struct ibtrs_clt_sess *sess, ibtrs_conf_fn *conf, >> + struct ibtrs_tag *tag, void *priv, >> + const struct kvec *vec, size_t usr_len, >> + struct scatterlist *sg, size_t sg_cnt, >> + size_t data_len, int dir) >> +{ >> + struct ibtrs_clt_io_req *req; >> + >> + req = &sess->reqs[tag->mem_id]; >> + ibtrs_clt_init_req(req, sess, conf, tag, priv, vec, usr_len, >> + sg, sg_cnt, data_len, dir); >> + return req; >> +} >> + >> +static inline struct ibtrs_clt_io_req * >> +ibtrs_clt_get_copy_req(struct ibtrs_clt_sess *alive_sess, >> + struct ibtrs_clt_io_req *fail_req) >> +{ >> + struct ibtrs_clt_io_req *req; >> + struct kvec vec = { >> + .iov_base = fail_req->iu->buf, >> + .iov_len = fail_req->usr_len >> + }; >> + >> + req = &alive_sess->reqs[fail_req->tag->mem_id]; >> + ibtrs_clt_init_req(req, alive_sess, fail_req->conf, fail_req->tag, >> + fail_req->priv, &vec, fail_req->usr_len, >> + fail_req->sglist, fail_req->sg_cnt, >> + fail_req->data_len, fail_req->dir); >> + return req; >> +} >> + >> +static int ibtrs_clt_write_req(struct ibtrs_clt_io_req *req); >> +static int ibtrs_clt_read_req(struct ibtrs_clt_io_req *req); >> + >> +static int ibtrs_clt_failover_req(struct ibtrs_clt *clt, >> + struct ibtrs_clt_io_req *fail_req) >> +{ >> + struct ibtrs_clt_sess *alive_sess; >> + struct ibtrs_clt_io_req *req; >> + int err = -ECONNABORTED; >> + struct path_it it; >> + >> + do_each_path(alive_sess, clt, &it) { >> + if (unlikely(alive_sess->state != IBTRS_CLT_CONNECTED)) >> + continue; >> + req = ibtrs_clt_get_copy_req(alive_sess, fail_req); >> + if (req->dir == DMA_TO_DEVICE) >> + err = ibtrs_clt_write_req(req); >> + else >> + err = ibtrs_clt_read_req(req); >> + if (unlikely(err)) { >> + req->in_use = false; >> + continue; >> + } >> + /* Success path */ >> + ibtrs_clt_inc_failover_cnt(&alive_sess->stats); >> + break; >> + } while_each_path(&it); >> + >> + return err; >> +} >> + >> +static void fail_all_outstanding_reqs(struct ibtrs_clt_sess *sess, >> + bool failover) >> +{ >> + struct ibtrs_clt *clt = sess->clt; >> + struct ibtrs_clt_io_req *req; >> + int i; >> + >> + if (!sess->reqs) >> + return; >> + for (i = 0; i < sess->queue_depth; ++i) { >> + bool notify; >> + int err = 0; >> + >> + req = &sess->reqs[i]; >> + if (!req->in_use) >> + continue; >> + >> + if (failover) >> + err = ibtrs_clt_failover_req(clt, req); >> + >> + notify = (!failover || err); >> + complete_rdma_req(req, -ECONNABORTED, notify); >> + } >> +} >> + >> +static void free_sess_reqs(struct ibtrs_clt_sess *sess) >> +{ >> + struct ibtrs_clt_io_req *req; >> + int i; >> + >> + if (!sess->reqs) >> + return; >> + for (i = 0; i < sess->queue_depth; ++i) { >> + req = &sess->reqs[i]; >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) >> + kfree(req->fr_list); >> + else if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) >> + kfree(req->fmr_list); >> + kfree(req->map_page); >> + ibtrs_iu_free(req->iu, DMA_TO_DEVICE, >> + sess->s.ib_dev->dev); >> + } >> + kfree(sess->reqs); >> + sess->reqs = NULL; >> +} >> + >> +static int alloc_sess_reqs(struct ibtrs_clt_sess *sess) >> +{ >> + struct ibtrs_clt_io_req *req; >> + void *mr_list; >> + int i; >> + >> + sess->reqs = kcalloc(sess->queue_depth, sizeof(*sess->reqs), >> + GFP_KERNEL); >> + if (unlikely(!sess->reqs)) >> + return -ENOMEM; >> + >> + for (i = 0; i < sess->queue_depth; ++i) { >> + req = &sess->reqs[i]; >> + req->iu = ibtrs_iu_alloc(i, sess->max_req_size, >> GFP_KERNEL, >> + sess->s.ib_dev->dev, >> DMA_TO_DEVICE, >> + ibtrs_clt_rdma_done); >> + if (unlikely(!req->iu)) >> + goto out; >> + mr_list = kmalloc_array(sess->max_pages_per_mr, >> + sizeof(void *), GFP_KERNEL); >> + if (unlikely(!mr_list)) >> + goto out; >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) >> + req->fr_list = mr_list; >> + else if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) >> + req->fmr_list = mr_list; >> + >> + req->map_page = kmalloc_array(sess->max_pages_per_mr, >> + sizeof(void *), GFP_KERNEL); >> + if (unlikely(!req->map_page)) >> + goto out; >> + } >> + >> + return 0; >> + >> +out: >> + free_sess_reqs(sess); >> + >> + return -ENOMEM; >> +} >> + >> +static int alloc_tags(struct ibtrs_clt *clt) >> +{ >> + unsigned int chunk_bits; >> + int err, i; >> + >> + clt->tags_map = kcalloc(BITS_TO_LONGS(clt->queue_depth), >> sizeof(long), >> + GFP_KERNEL); >> + if (unlikely(!clt->tags_map)) { >> + err = -ENOMEM; >> + goto out_err; >> + } >> + clt->tags = kcalloc(clt->queue_depth, TAG_SIZE(clt), GFP_KERNEL); >> + if (unlikely(!clt->tags)) { >> + err = -ENOMEM; >> + goto err_map; >> + } >> + chunk_bits = ilog2(clt->queue_depth - 1) + 1; >> + for (i = 0; i < clt->queue_depth; i++) { >> + struct ibtrs_tag *tag; >> + >> + tag = GET_TAG(clt, i); >> + tag->mem_id = i; >> + tag->mem_off = i << (MAX_IMM_PAYL_BITS - chunk_bits); >> + } >> + >> + return 0; >> + >> +err_map: >> + kfree(clt->tags_map); >> + clt->tags_map = NULL; >> +out_err: >> + return err; >> +} >> + >> +static void free_tags(struct ibtrs_clt *clt) >> +{ >> + kfree(clt->tags_map); >> + clt->tags_map = NULL; >> + kfree(clt->tags); >> + clt->tags = NULL; >> +} >> + >> +static void query_fast_reg_mode(struct ibtrs_clt_sess *sess) >> +{ >> + struct ibtrs_ib_dev *ib_dev; >> + u64 max_pages_per_mr; >> + int mr_page_shift; >> + >> + ib_dev = sess->s.ib_dev; >> + if (ib_dev->dev->alloc_fmr && ib_dev->dev->dealloc_fmr && >> + ib_dev->dev->map_phys_fmr && ib_dev->dev->unmap_fmr) { >> + sess->fast_reg_mode = IBTRS_FAST_MEM_FMR; >> + ibtrs_info(sess, "Device %s supports FMR\n", >> ib_dev->dev->name); >> + } >> + if (ib_dev->attrs.device_cap_flags & IB_DEVICE_MEM_MGT_EXTENSIONS >> && >> + use_fr) { >> + sess->fast_reg_mode = IBTRS_FAST_MEM_FR; >> + ibtrs_info(sess, "Device %s supports FR\n", >> ib_dev->dev->name); >> + } >> + >> + /* >> + * Use the smallest page size supported by the HCA, down to a >> + * minimum of 4096 bytes. We're unlikely to build large sglists >> + * out of smaller entries. >> + */ >> + mr_page_shift = max(12, ffs(ib_dev->attrs.page_size_cap) - >> 1); >> + sess->mr_page_size = 1 << mr_page_shift; >> + sess->max_sge = ib_dev->attrs.max_sge; >> + sess->mr_page_mask = ~((u64)sess->mr_page_size - 1); >> + max_pages_per_mr = ib_dev->attrs.max_mr_size; >> + do_div(max_pages_per_mr, sess->mr_page_size); >> + sess->max_pages_per_mr = min_t(u64, sess->max_pages_per_mr, >> + max_pages_per_mr); >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) { >> + sess->max_pages_per_mr = >> + min_t(u32, sess->max_pages_per_mr, >> + ib_dev->attrs.max_fast_reg_page_list_len); >> + } >> + sess->mr_max_size = sess->mr_page_size * sess->max_pages_per_mr; >> +} >> + >> +static int alloc_con_fast_pool(struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + struct ibtrs_fr_pool *fr_pool; >> + int err = 0; >> + >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FR) { >> + fr_pool = ibtrs_create_fr_pool(sess->s.ib_dev->dev, >> + sess->s.ib_dev->pd, >> + sess->queue_depth, >> + sess->max_pages_per_mr); >> + if (unlikely(IS_ERR(fr_pool))) { >> + err = PTR_ERR(fr_pool); >> + ibtrs_err(sess, "FR pool allocation failed, err: >> %d\n", >> + err); >> + return err; >> + } >> + con->fr_pool = fr_pool; >> + } >> + >> + return err; >> +} >> + >> +static void free_con_fast_pool(struct ibtrs_clt_con *con) >> +{ >> + if (con->fr_pool) { >> + ibtrs_destroy_fr_pool(con->fr_pool); >> + con->fr_pool = NULL; >> + } >> +} >> + >> +static int alloc_sess_fast_pool(struct ibtrs_clt_sess *sess) >> +{ >> + struct ib_fmr_pool_param fmr_param; >> + struct ib_fmr_pool *fmr_pool; >> + int err = 0; >> + >> + if (sess->fast_reg_mode == IBTRS_FAST_MEM_FMR) { >> + memset(&fmr_param, 0, sizeof(fmr_param)); >> + fmr_param.pool_size = sess->queue_depth * >> + sess->max_pages_per_mr; >> + fmr_param.dirty_watermark = fmr_param.pool_size / 4; >> + fmr_param.cache = 0; >> + fmr_param.max_pages_per_fmr = sess->max_pages_per_mr; >> + fmr_param.page_shift = ilog2(sess->mr_page_size); >> + fmr_param.access = (IB_ACCESS_LOCAL_WRITE | >> + IB_ACCESS_REMOTE_WRITE); >> + >> + fmr_pool = ib_create_fmr_pool(sess->s.ib_dev->pd, >> &fmr_param); >> + if (unlikely(IS_ERR(fmr_pool))) { >> + err = PTR_ERR(fmr_pool); >> + ibtrs_err(sess, "FMR pool allocation failed, err: >> %d\n", >> + err); >> + return err; >> + } >> + sess->fmr_pool = fmr_pool; >> + } >> + >> + return err; >> +} >> + >> +static void free_sess_fast_pool(struct ibtrs_clt_sess *sess) >> +{ >> + if (sess->fmr_pool) { >> + ib_destroy_fmr_pool(sess->fmr_pool); >> + sess->fmr_pool = NULL; >> + } >> +} >> + >> +static int alloc_sess_io_bufs(struct ibtrs_clt_sess *sess) >> +{ >> + int ret; >> + >> + ret = alloc_sess_reqs(sess); >> + if (unlikely(ret)) { >> + ibtrs_err(sess, "alloc_sess_reqs(), err: %d\n", ret); >> + return ret; >> + } >> + ret = alloc_sess_fast_pool(sess); >> + if (unlikely(ret)) { >> + ibtrs_err(sess, "alloc_sess_fast_pool(), err: %d\n", ret); >> + goto free_reqs; >> + } >> + >> + return 0; >> + >> +free_reqs: >> + free_sess_reqs(sess); >> + >> + return ret; >> +} >> + >> +static void free_sess_io_bufs(struct ibtrs_clt_sess *sess) >> +{ >> + free_sess_reqs(sess); >> + free_sess_fast_pool(sess); >> +} >> + >> +static bool __ibtrs_clt_change_state(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state new_state) >> +{ >> + enum ibtrs_clt_state old_state; >> + bool changed = false; >> + >> + old_state = sess->state; >> + switch (new_state) { >> + case IBTRS_CLT_CONNECTING: >> + switch (old_state) { >> + case IBTRS_CLT_RECONNECTING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_RECONNECTING: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTED: >> + case IBTRS_CLT_CONNECTING_ERR: >> + case IBTRS_CLT_CLOSED: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CONNECTED: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CONNECTING_ERR: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CLOSING: >> + switch (old_state) { >> + case IBTRS_CLT_CONNECTING: >> + case IBTRS_CLT_CONNECTING_ERR: >> + case IBTRS_CLT_RECONNECTING: >> + case IBTRS_CLT_CONNECTED: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_CLOSED: >> + switch (old_state) { >> + case IBTRS_CLT_CLOSING: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + case IBTRS_CLT_DEAD: >> + switch (old_state) { >> + case IBTRS_CLT_CLOSED: >> + changed = true; >> + /* FALLTHRU */ >> + default: >> + break; >> + } >> + break; >> + default: >> + break; >> + } >> + if (changed) { >> + sess->state = new_state; >> + wake_up_locked(&sess->state_wq); >> + } >> + >> + return changed; >> +} >> + >> +static bool ibtrs_clt_change_state_from_to(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state old_state, >> + enum ibtrs_clt_state new_state) >> +{ >> + bool changed = false; >> + >> + spin_lock_irq(&sess->state_wq.lock); >> + if (sess->state == old_state) >> + changed = __ibtrs_clt_change_state(sess, new_state); >> + spin_unlock_irq(&sess->state_wq.lock); >> + >> + return changed; >> +} >> + >> +static bool ibtrs_clt_change_state_get_old(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state new_state, >> + enum ibtrs_clt_state >> *old_state) >> +{ >> + bool changed; >> + >> + spin_lock_irq(&sess->state_wq.lock); >> + *old_state = sess->state; >> + changed = __ibtrs_clt_change_state(sess, new_state); >> + spin_unlock_irq(&sess->state_wq.lock); >> + >> + return changed; >> +} >> + >> +static bool ibtrs_clt_change_state(struct ibtrs_clt_sess *sess, >> + enum ibtrs_clt_state new_state) >> +{ >> + enum ibtrs_clt_state old_state; >> + >> + return ibtrs_clt_change_state_get_old(sess, new_state, >> &old_state); >> +} >> + >> +static enum ibtrs_clt_state ibtrs_clt_state(struct ibtrs_clt_sess *sess) >> +{ >> + enum ibtrs_clt_state state; >> + >> + spin_lock_irq(&sess->state_wq.lock); >> + state = sess->state; >> + spin_unlock_irq(&sess->state_wq.lock); >> + >> + return state; >> +} >> + >> +static void ibtrs_clt_hb_err_handler(struct ibtrs_con *c, int err) >> +{ >> + struct ibtrs_clt_con *con; >> + >> + (void)err; >> + con = container_of(c, typeof(*con), c); >> + ibtrs_rdma_error_recovery(con); >> +} >> + >> +static void ibtrs_clt_init_hb(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_init_hb(&sess->s, &io_comp_cqe, >> + IBTRS_HB_INTERVAL_MS, >> + IBTRS_HB_MISSED_MAX, >> + ibtrs_clt_hb_err_handler, >> + ibtrs_wq); >> +} >> + >> +static void ibtrs_clt_start_hb(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_start_hb(&sess->s); >> +} >> + >> +static void ibtrs_clt_stop_hb(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_stop_hb(&sess->s); >> +} >> + >> +static void ibtrs_clt_reconnect_work(struct work_struct *work); >> +static void ibtrs_clt_close_work(struct work_struct *work); >> + >> +static struct ibtrs_clt_sess *alloc_sess(struct ibtrs_clt *clt, >> + const struct ibtrs_addr *path, >> + size_t con_num, u16 max_segments) >> +{ >> + struct ibtrs_clt_sess *sess; >> + int err = -ENOMEM; >> + int cpu; >> + >> + sess = kzalloc(sizeof(*sess), GFP_KERNEL); >> + if (unlikely(!sess)) >> + goto err; >> + >> + /* Extra connection for user messages */ >> + con_num += 1; >> + >> + sess->s.con = kcalloc(con_num, sizeof(*sess->s.con), GFP_KERNEL); >> + if (unlikely(!sess->s.con)) >> + goto err_free_sess; >> + >> + mutex_init(&sess->init_mutex); >> + uuid_gen(&sess->s.uuid); >> + memcpy(&sess->s.dst_addr, path->dst, >> + rdma_addr_size((struct sockaddr *)path->dst)); >> + >> + /* >> + * rdma_resolve_addr() passes src_addr to cma_bind_addr, which >> + * checks the sa_family to be non-zero. If user passed >> src_addr=NULL >> + * the sess->src_addr will contain only zeros, which is then fine. >> + */ >> + if (path->src) >> + memcpy(&sess->s.src_addr, path->src, >> + rdma_addr_size((struct sockaddr *)path->src)); >> + strlcpy(sess->s.sessname, clt->sessname, >> sizeof(sess->s.sessname)); >> + sess->s.con_num = con_num; >> + sess->clt = clt; >> + sess->max_pages_per_mr = max_segments; >> + init_waitqueue_head(&sess->state_wq); >> + sess->state = IBTRS_CLT_CONNECTING; >> + atomic_set(&sess->connected_cnt, 0); >> + INIT_WORK(&sess->close_work, ibtrs_clt_close_work); >> + INIT_DELAYED_WORK(&sess->reconnect_dwork, >> ibtrs_clt_reconnect_work); >> + ibtrs_clt_init_hb(sess); >> + >> + sess->mp_skip_entry = alloc_percpu(typeof(*sess->mp_skip_entry)); >> + if (unlikely(!sess->mp_skip_entry)) >> + goto err_free_con; >> + >> + for_each_possible_cpu(cpu) >> + INIT_LIST_HEAD(per_cpu_ptr(sess->mp_skip_entry, cpu)); >> + >> + err = ibtrs_clt_init_stats(&sess->stats); >> + if (unlikely(err)) >> + goto err_free_percpu; >> + >> + return sess; >> + >> +err_free_percpu: >> + free_percpu(sess->mp_skip_entry); >> +err_free_con: >> + kfree(sess->s.con); >> +err_free_sess: >> + kfree(sess); >> +err: >> + return ERR_PTR(err); >> +} >> + >> +static void free_sess(struct ibtrs_clt_sess *sess) >> +{ >> + ibtrs_clt_free_stats(&sess->stats); >> + free_percpu(sess->mp_skip_entry); >> + kfree(sess->s.con); >> + kfree(sess->srv_rdma_addr); >> + kfree(sess); >> +} >> + >> +static int create_con(struct ibtrs_clt_sess *sess, unsigned int cid) >> +{ >> + struct ibtrs_clt_con *con; >> + >> + con = kzalloc(sizeof(*con), GFP_KERNEL); >> + if (unlikely(!con)) >> + return -ENOMEM; >> + >> + /* Map first two connections to the first CPU */ >> + con->cpu = (cid ? cid - 1 : 0) % nr_cpu_ids; >> + con->c.cid = cid; >> + con->c.sess = &sess->s; >> + atomic_set(&con->io_cnt, 0); >> + >> + sess->s.con[cid] = &con->c; >> + >> + return 0; >> +} >> + >> +static void destroy_con(struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + >> + sess->s.con[con->c.cid] = NULL; >> + kfree(con); >> +} >> + >> +static int create_con_cq_qp(struct ibtrs_clt_con *con) >> +{ >> + struct ibtrs_clt_sess *sess = to_clt_sess(con->c.sess); >> + u16 cq_size, wr_queue_size; >> + int err, cq_vector; >> + >> + /* >> + * This function can fail, but still destroy_con_cq_qp() should >> + * be called, this is because create_con_cq_qp() is called on cm >> + * event path, thus caller/waiter never knows: have we failed >> before >> + * create_con_cq_qp() or after. To solve this dilemma without >> + * creating any additional flags just allow destroy_con_cq_qp() be >> + * called many times. >> + */ >> + >> + if (con->c.cid == 0) { >> + cq_size = SERVICE_CON_QUEUE_DEPTH; >> + /* + 2 for drain and heartbeat */ >> + wr_queue_size = SERVICE_CON_QUEUE_DEPTH + 2; >> + /* We must be the first here */ >> + if (WARN_ON(sess->s.ib_dev)) >> + return -EINVAL; >> + >> + /* >> + * The whole session uses device from user connection. >> + * Be careful not to close user connection before ib dev >> + * is gracefully put. >> + */ >> + sess->s.ib_dev = ibtrs_ib_dev_find_get(con->c.cm_id); >> + if (unlikely(!sess->s.ib_dev)) { >> + ibtrs_wrn(sess, "ibtrs_ib_dev_find_get(): no >> memory\n"); >> + return -ENOMEM; >> + } >> + sess->s.ib_dev_ref = 1; >> + query_fast_reg_mode(sess); >> + } else { >> + int num_wr; >> + >> + /* >> + * Here we assume that session members are correctly set. >> + * This is always true if user connection (cid == 0) is >> + * established first. >> + */ >> + if (WARN_ON(!sess->s.ib_dev)) >> + return -EINVAL; >> + if (WARN_ON(!sess->queue_depth)) >> + return -EINVAL; >> + >> + /* Shared between connections */ >> + sess->s.ib_dev_ref++; >> + cq_size = sess->queue_depth; >> + num_wr = DIV_ROUND_UP(sess->max_pages_per_mr, >> sess->max_sge); >> + wr_queue_size = sess->s.ib_dev->attrs.max_qp_wr; >> + wr_queue_size = min_t(int, wr_queue_size, >> + sess->queue_depth * num_wr * >> + (use_fr ? 3 : 2) + 1); >> + } >> + cq_vector = con->cpu % sess->s.ib_dev->dev->num_comp_vectors; >> + err = ibtrs_cq_qp_create(&sess->s, &con->c, sess->max_sge, >> + cq_vector, cq_size, wr_queue_size, >> + IB_POLL_SOFTIRQ); >> + /* >> + * In case of error we do not bother to clean previous >> allocations, >> + * since destroy_con_cq_qp() must be called. >> + */ -- To unsubscribe from this list: send the line "unsubscribe linux-rdma" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html