From 3e034725c0d814370a75b249c0ba794262cacd0f Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Fri, 28 Jul 2017 13:56:20 +0200 Subject: [PATCH] net/smc: common functions for RMBs and send buffers Creation and deletion of SMC receive and send buffers shares a high amount of common code . This patch introduces common functions to get rid of duplicate code. Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/af_smc.c | 16 +-- net/smc/smc_core.c | 348 +++++++++++++++++++-------------------------- net/smc/smc_core.h | 3 +- 3 files changed, 148 insertions(+), 219 deletions(-) diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index e0a95d50bf87..75518879b68a 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -436,12 +436,8 @@ static int smc_connect_rdma(struct smc_sock *smc) smc_conn_save_peer_info(smc, &aclc); - rc = smc_sndbuf_create(smc); - if (rc) { - reason_code = SMC_CLC_DECL_MEM; - goto decline_rdma_unlock; - } - rc = smc_rmb_create(smc); + /* create send buffer and rmb */ + rc = smc_buf_create(smc); if (rc) { reason_code = SMC_CLC_DECL_MEM; goto decline_rdma_unlock; @@ -813,12 +809,8 @@ static void smc_listen_work(struct work_struct *work) } link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK]; - rc = smc_sndbuf_create(new_smc); - if (rc) { - reason_code = SMC_CLC_DECL_MEM; - goto decline_rdma; - } - rc = smc_rmb_create(new_smc); + /* create send buffer and rmb */ + rc = smc_buf_create(new_smc); if (rc) { reason_code = SMC_CLC_DECL_MEM; goto decline_rdma; diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index 8795c7ed9ce4..ab8cdac5edb3 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -206,16 +206,12 @@ out: return rc; } -static void smc_sndbuf_unuse(struct smc_connection *conn) +static void smc_buf_unuse(struct smc_connection *conn) { if (conn->sndbuf_desc) { conn->sndbuf_desc->used = 0; conn->sndbuf_size = 0; } -} - -static void smc_rmb_unuse(struct smc_connection *conn) -{ if (conn->rmb_desc) { conn->rmb_desc->reused = true; conn->rmb_desc->used = 0; @@ -232,8 +228,7 @@ void smc_conn_free(struct smc_connection *conn) return; smc_cdc_tx_dismiss_slots(conn); smc_lgr_unregister_conn(conn); - smc_rmb_unuse(conn); - smc_sndbuf_unuse(conn); + smc_buf_unuse(conn); } static void smc_link_clear(struct smc_link *lnk) @@ -246,51 +241,57 @@ static void smc_link_clear(struct smc_link *lnk) smc_wr_free_link_mem(lnk); } -static void smc_lgr_free_sndbufs(struct smc_link_group *lgr) +static void smc_buf_free(struct smc_buf_desc *buf_desc, struct smc_link *lnk, + bool is_rmb) { - struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK]; - struct smc_buf_desc *sndbuf_desc, *bf_desc; - int i; - - for (i = 0; i < SMC_RMBE_SIZES; i++) { - list_for_each_entry_safe(sndbuf_desc, bf_desc, &lgr->sndbufs[i], - list) { - list_del(&sndbuf_desc->list); - smc_ib_buf_unmap_sg(lnk->smcibdev, sndbuf_desc, - DMA_TO_DEVICE); - sg_free_table(&sndbuf_desc->sgt[SMC_SINGLE_LINK]); - free_pages((unsigned long)sndbuf_desc->cpu_addr, - sndbuf_desc->order); - kfree(sndbuf_desc); - } + if (is_rmb) { + if (buf_desc->mr_rx[SMC_SINGLE_LINK]) + smc_ib_put_memory_region( + buf_desc->mr_rx[SMC_SINGLE_LINK]); + smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc, + DMA_FROM_DEVICE); + } else { + smc_ib_buf_unmap_sg(lnk->smcibdev, buf_desc, + DMA_TO_DEVICE); } + sg_free_table(&buf_desc->sgt[SMC_SINGLE_LINK]); + if (buf_desc->cpu_addr) + free_pages((unsigned long)buf_desc->cpu_addr, buf_desc->order); + kfree(buf_desc); } -static void smc_lgr_free_rmbs(struct smc_link_group *lgr) +static void __smc_lgr_free_bufs(struct smc_link_group *lgr, bool is_rmb) { struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK]; - struct smc_buf_desc *rmb_desc, *bf_desc; + struct smc_buf_desc *buf_desc, *bf_desc; + struct list_head *buf_list; int i; for (i = 0; i < SMC_RMBE_SIZES; i++) { - list_for_each_entry_safe(rmb_desc, bf_desc, &lgr->rmbs[i], + if (is_rmb) + buf_list = &lgr->rmbs[i]; + else + buf_list = &lgr->sndbufs[i]; + list_for_each_entry_safe(buf_desc, bf_desc, buf_list, list) { - list_del(&rmb_desc->list); - smc_ib_put_memory_region( - rmb_desc->mr_rx[SMC_SINGLE_LINK]); - smc_ib_buf_unmap_sg(lnk->smcibdev, rmb_desc, - DMA_FROM_DEVICE); - kfree(rmb_desc->cpu_addr); - kfree(rmb_desc); + list_del(&buf_desc->list); + smc_buf_free(buf_desc, lnk, is_rmb); } } } +static void smc_lgr_free_bufs(struct smc_link_group *lgr) +{ + /* free send buffers */ + __smc_lgr_free_bufs(lgr, false); + /* free rmbs */ + __smc_lgr_free_bufs(lgr, true); +} + /* remove a link group */ void smc_lgr_free(struct smc_link_group *lgr) { - smc_lgr_free_rmbs(lgr); - smc_lgr_free_sndbufs(lgr); + smc_lgr_free_bufs(lgr); smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]); kfree(lgr); } @@ -455,45 +456,25 @@ out: return rc ? rc : local_contact; } -/* try to reuse a sndbuf description slot of the sndbufs list for a certain - * buf_size; if not available, return NULL +/* try to reuse a sndbuf or rmb description slot for a certain + * buffer size; if not available, return NULL */ static inline -struct smc_buf_desc *smc_sndbuf_get_slot(struct smc_link_group *lgr, - int compressed_bufsize) +struct smc_buf_desc *smc_buf_get_slot(struct smc_link_group *lgr, + int compressed_bufsize, + rwlock_t *lock, + struct list_head *buf_list) { - struct smc_buf_desc *sndbuf_slot; - - read_lock_bh(&lgr->sndbufs_lock); - list_for_each_entry(sndbuf_slot, &lgr->sndbufs[compressed_bufsize], - list) { - if (cmpxchg(&sndbuf_slot->used, 0, 1) == 0) { - read_unlock_bh(&lgr->sndbufs_lock); - return sndbuf_slot; - } - } - read_unlock_bh(&lgr->sndbufs_lock); - return NULL; -} + struct smc_buf_desc *buf_slot; -/* try to reuse an rmb description slot of the rmbs list for a certain - * rmbe_size; if not available, return NULL - */ -static inline -struct smc_buf_desc *smc_rmb_get_slot(struct smc_link_group *lgr, - int compressed_bufsize) -{ - struct smc_buf_desc *rmb_slot; - - read_lock_bh(&lgr->rmbs_lock); - list_for_each_entry(rmb_slot, &lgr->rmbs[compressed_bufsize], - list) { - if (cmpxchg(&rmb_slot->used, 0, 1) == 0) { - read_unlock_bh(&lgr->rmbs_lock); - return rmb_slot; + read_lock_bh(lock); + list_for_each_entry(buf_slot, buf_list, list) { + if (cmpxchg(&buf_slot->used, 0, 1) == 0) { + read_unlock_bh(lock); + return buf_slot; } } - read_unlock_bh(&lgr->rmbs_lock); + read_unlock_bh(lock); return NULL; } @@ -506,185 +487,142 @@ static inline int smc_rmb_wnd_update_limit(int rmbe_size) return min_t(int, rmbe_size / 10, SOCK_MIN_SNDBUF / 2); } -/* create the tx buffer for an SMC socket */ -int smc_sndbuf_create(struct smc_sock *smc) +static int __smc_buf_create(struct smc_sock *smc, bool is_rmb) { struct smc_connection *conn = &smc->conn; struct smc_link_group *lgr = conn->lgr; - struct smc_buf_desc *sndbuf_desc; + struct smc_buf_desc *buf_desc = NULL; + struct list_head *buf_list; int bufsize, bufsize_short; + struct smc_link *lnk; + int sk_buf_size; + rwlock_t *lock; int rc; - /* use socket send buffer size (w/o overhead) as start value */ + lnk = &lgr->lnk[SMC_SINGLE_LINK]; + if (is_rmb) + /* use socket recv buffer size (w/o overhead) as start value */ + sk_buf_size = smc->sk.sk_rcvbuf / 2; + else + /* use socket send buffer size (w/o overhead) as start value */ + sk_buf_size = smc->sk.sk_sndbuf / 2; + for (bufsize_short = smc_compress_bufsize(smc->sk.sk_sndbuf / 2); bufsize_short >= 0; bufsize_short--) { - bufsize = smc_uncompress_bufsize(bufsize_short); - if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC) - continue; - - /* check for reusable sndbuf_slot in the link group */ - sndbuf_desc = smc_sndbuf_get_slot(lgr, bufsize_short); - if (sndbuf_desc) { - memset(sndbuf_desc->cpu_addr, 0, bufsize); - break; /* found reusable slot */ - } - /* try to alloc a new send buffer */ - sndbuf_desc = kzalloc(sizeof(*sndbuf_desc), GFP_KERNEL); - if (!sndbuf_desc) - break; /* give up with -ENOMEM */ - sndbuf_desc->cpu_addr = - (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN | - __GFP_NOMEMALLOC | - __GFP_NORETRY | __GFP_ZERO, - get_order(bufsize)); - if (!sndbuf_desc->cpu_addr) { - kfree(sndbuf_desc); - sndbuf_desc = NULL; - /* if send buffer allocation has failed, - * try a smaller one - */ - continue; - } - sndbuf_desc->order = get_order(bufsize); - - rc = sg_alloc_table(&sndbuf_desc->sgt[SMC_SINGLE_LINK], 1, - GFP_KERNEL); - if (rc) { - free_pages((unsigned long)sndbuf_desc->cpu_addr, - sndbuf_desc->order); - kfree(sndbuf_desc); - sndbuf_desc = NULL; - continue; + if (is_rmb) { + lock = &lgr->rmbs_lock; + buf_list = &lgr->rmbs[bufsize_short]; + } else { + lock = &lgr->sndbufs_lock; + buf_list = &lgr->sndbufs[bufsize_short]; } - sg_set_buf(sndbuf_desc->sgt[SMC_SINGLE_LINK].sgl, - sndbuf_desc->cpu_addr, bufsize); - - rc = smc_ib_buf_map_sg(lgr->lnk[SMC_SINGLE_LINK].smcibdev, - sndbuf_desc, DMA_TO_DEVICE); - if (rc != 1) { - sg_free_table(&sndbuf_desc->sgt[SMC_SINGLE_LINK]); - free_pages((unsigned long)sndbuf_desc->cpu_addr, - sndbuf_desc->order); - kfree(sndbuf_desc); - sndbuf_desc = NULL; - continue; /* if mapping failed, try smaller one */ - } - - sndbuf_desc->used = 1; - write_lock_bh(&lgr->sndbufs_lock); - list_add(&sndbuf_desc->list, &lgr->sndbufs[bufsize_short]); - write_unlock_bh(&lgr->sndbufs_lock); - break; - } - if (sndbuf_desc && sndbuf_desc->cpu_addr) { - conn->sndbuf_desc = sndbuf_desc; - conn->sndbuf_size = bufsize; - smc->sk.sk_sndbuf = bufsize * 2; - atomic_set(&conn->sndbuf_space, bufsize); - return 0; - } else { - return -ENOMEM; - } -} - -/* create the RMB for an SMC socket (even though the SMC protocol - * allows more than one RMB-element per RMB, the Linux implementation - * uses just one RMB-element per RMB, i.e. uses an extra RMB for every - * connection in a link group - */ -int smc_rmb_create(struct smc_sock *smc) -{ - struct smc_connection *conn = &smc->conn; - struct smc_link_group *lgr = conn->lgr; - struct smc_buf_desc *rmb_desc; - int bufsize, bufsize_short; - int rc; - - /* use socket recv buffer size (w/o overhead) as start value */ - for (bufsize_short = smc_compress_bufsize(smc->sk.sk_rcvbuf / 2); - bufsize_short >= 0; bufsize_short--) { bufsize = smc_uncompress_bufsize(bufsize_short); if ((1 << get_order(bufsize)) > SG_MAX_SINGLE_ALLOC) continue; - /* check for reusable rmb_slot in the link group */ - rmb_desc = smc_rmb_get_slot(lgr, bufsize_short); - if (rmb_desc) { - memset(rmb_desc->cpu_addr, 0, bufsize); + /* check for reusable slot in the link group */ + buf_desc = smc_buf_get_slot(lgr, bufsize_short, lock, buf_list); + if (buf_desc) { + memset(buf_desc->cpu_addr, 0, bufsize); break; /* found reusable slot */ } - /* try to alloc a new RMB */ - rmb_desc = kzalloc(sizeof(*rmb_desc), GFP_KERNEL); - if (!rmb_desc) + /* try to allocate the determined number of pages */ + buf_desc = kzalloc(sizeof(*buf_desc), GFP_KERNEL); + if (!buf_desc) break; /* give up with -ENOMEM */ - rmb_desc->cpu_addr = + + buf_desc->cpu_addr = (void *)__get_free_pages(GFP_KERNEL | __GFP_NOWARN | __GFP_NOMEMALLOC | __GFP_NORETRY | __GFP_ZERO, get_order(bufsize)); - if (!rmb_desc->cpu_addr) { - kfree(rmb_desc); - rmb_desc = NULL; + if (!buf_desc->cpu_addr) { + kfree(buf_desc); + buf_desc = NULL; continue; } - rmb_desc->order = get_order(bufsize); - rc = sg_alloc_table(&rmb_desc->sgt[SMC_SINGLE_LINK], 1, + rc = sg_alloc_table(&buf_desc->sgt[SMC_SINGLE_LINK], 1, GFP_KERNEL); if (rc) { - free_pages((unsigned long)rmb_desc->cpu_addr, - rmb_desc->order); - kfree(rmb_desc); - rmb_desc = NULL; + smc_buf_free(buf_desc, lnk, is_rmb); + buf_desc = NULL; continue; } - sg_set_buf(rmb_desc->sgt[SMC_SINGLE_LINK].sgl, - rmb_desc->cpu_addr, bufsize); + sg_set_buf(buf_desc->sgt[SMC_SINGLE_LINK].sgl, + buf_desc->cpu_addr, bufsize); - rc = smc_ib_buf_map_sg(lgr->lnk[SMC_SINGLE_LINK].smcibdev, - rmb_desc, DMA_FROM_DEVICE); + /* map sg table to DMA address */ + rc = smc_ib_buf_map_sg(lnk->smcibdev, buf_desc, is_rmb ? + DMA_FROM_DEVICE : DMA_TO_DEVICE); + /* SMC protocol depends on mapping to one DMA address only */ if (rc != 1) { - sg_free_table(&rmb_desc->sgt[SMC_SINGLE_LINK]); - free_pages((unsigned long)rmb_desc->cpu_addr, - rmb_desc->order); - kfree(rmb_desc); - rmb_desc = NULL; - continue; /* if mapping failed, try smaller one */ + smc_buf_free(buf_desc, lnk, is_rmb); + buf_desc = NULL; + continue; /* if mapping failed, try smaller one */ } - rc = smc_ib_get_memory_region(lgr->lnk[SMC_SINGLE_LINK].roce_pd, - IB_ACCESS_REMOTE_WRITE | - IB_ACCESS_LOCAL_WRITE, - rmb_desc); - if (rc) { - smc_ib_buf_unmap_sg(lgr->lnk[SMC_SINGLE_LINK].smcibdev, - rmb_desc, DMA_FROM_DEVICE); - sg_free_table(&rmb_desc->sgt[SMC_SINGLE_LINK]); - free_pages((unsigned long)rmb_desc->cpu_addr, - rmb_desc->order); - kfree(rmb_desc); - rmb_desc = NULL; - continue; + + /* create a new memory region for the RMB */ + if (is_rmb) { + rc = smc_ib_get_memory_region(lnk->roce_pd, + IB_ACCESS_REMOTE_WRITE | + IB_ACCESS_LOCAL_WRITE, + buf_desc); + if (rc) { + smc_buf_free(buf_desc, lnk, is_rmb); + buf_desc = NULL; + continue; + } } - rmb_desc->used = 1; - write_lock_bh(&lgr->rmbs_lock); - list_add(&rmb_desc->list, &lgr->rmbs[bufsize_short]); - write_unlock_bh(&lgr->rmbs_lock); - break; + buf_desc->used = 1; + write_lock_bh(lock); + list_add(&buf_desc->list, buf_list); + write_unlock_bh(lock); + break; /* found */ } - if (rmb_desc && rmb_desc->cpu_addr) { - conn->rmb_desc = rmb_desc; + + if (!buf_desc || !buf_desc->cpu_addr) + return -ENOMEM; + + if (is_rmb) { + conn->rmb_desc = buf_desc; conn->rmbe_size = bufsize; conn->rmbe_size_short = bufsize_short; smc->sk.sk_rcvbuf = bufsize * 2; atomic_set(&conn->bytes_to_rcv, 0); conn->rmbe_update_limit = smc_rmb_wnd_update_limit(bufsize); - return 0; } else { - return -ENOMEM; + conn->sndbuf_desc = buf_desc; + conn->sndbuf_size = bufsize; + smc->sk.sk_sndbuf = bufsize * 2; + atomic_set(&conn->sndbuf_space, bufsize); } + return 0; +} + +/* create the send and receive buffer for an SMC socket; + * receive buffers are called RMBs; + * (even though the SMC protocol allows more than one RMB-element per RMB, + * the Linux implementation uses just one RMB-element per RMB, i.e. uses an + * extra RMB for every connection in a link group + */ +int smc_buf_create(struct smc_sock *smc) +{ + int rc; + + /* create send buffer */ + rc = __smc_buf_create(smc, false); + if (rc) + return rc; + /* create rmb */ + rc = __smc_buf_create(smc, true); + if (rc) + smc_buf_free(smc->conn.sndbuf_desc, + &smc->conn.lgr->lnk[SMC_SINGLE_LINK], false); + return rc; } static inline int smc_rmb_reserve_rtoken_idx(struct smc_link_group *lgr) diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index 72c25cb3eb89..1d713e8e067c 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -186,8 +186,7 @@ struct smc_clc_msg_accept_confirm; void smc_lgr_free(struct smc_link_group *lgr); void smc_lgr_terminate(struct smc_link_group *lgr); -int smc_sndbuf_create(struct smc_sock *smc); -int smc_rmb_create(struct smc_sock *smc); +int smc_buf_create(struct smc_sock *smc); int smc_rmb_rtoken_handling(struct smc_connection *conn, struct smc_clc_msg_accept_confirm *clc); #endif -- 2.30.2