From 2a4c57a9e731fa7bd20b028ca078a0ab0ec2485e Mon Sep 17 00:00:00 2001 From: Karsten Graul Date: Tue, 15 May 2018 17:04:59 +0200 Subject: net/smc: use a workqueue to defer llc send SMC handles deferred work in tasklets. As tasklets cannot sleep this can result in rare EBUSY conditions, so defer this work in a work queue. The high level api functions do not defer work because they can sleep until the llc send is actually completed. Signed-off-by: Karsten Graul Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/smc_core.c | 10 ++-- net/smc/smc_core.h | 1 + net/smc/smc_llc.c | 132 ++++++++++++++++++++++++++++++++++++++--------------- net/smc/smc_llc.h | 4 +- 4 files changed, 104 insertions(+), 43 deletions(-) (limited to 'net/smc') diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index ba7dae819ac8..4523bbad8a15 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -194,10 +194,12 @@ static int smc_lgr_create(struct smc_sock *smc, smc_ib_setup_per_ibdev(smcibdev); get_random_bytes(rndvec, sizeof(rndvec)); lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) + (rndvec[2] << 16); - smc_llc_link_init(lnk); - rc = smc_wr_alloc_link_mem(lnk); + rc = smc_llc_link_init(lnk); if (rc) goto free_lgr; + rc = smc_wr_alloc_link_mem(lnk); + if (rc) + goto clear_llc_lnk; rc = smc_ib_create_protection_domain(lnk); if (rc) goto free_link_mem; @@ -221,6 +223,8 @@ dealloc_pd: smc_ib_dealloc_protection_domain(lnk); free_link_mem: smc_wr_free_link_mem(lnk); +clear_llc_lnk: + smc_llc_link_clear(lnk); free_lgr: kfree(lgr); out: @@ -266,6 +270,7 @@ void smc_conn_free(struct smc_connection *conn) static void smc_link_clear(struct smc_link *lnk) { lnk->peer_qpn = 0; + smc_llc_link_clear(lnk); smc_ib_modify_qp_reset(lnk); smc_wr_free_link(lnk); smc_ib_destroy_queue_pair(lnk); @@ -323,7 +328,6 @@ static void smc_lgr_free_bufs(struct smc_link_group *lgr) /* remove a link group */ void smc_lgr_free(struct smc_link_group *lgr) { - smc_llc_link_flush(&lgr->lnk[SMC_SINGLE_LINK]); smc_lgr_free_bufs(lgr); smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]); kfree(lgr); diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index 9398e235d74b..d1753850684b 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -96,6 +96,7 @@ struct smc_link { u8 link_id; /* unique # within link group */ enum smc_link_state state; /* state of link */ + struct workqueue_struct *llc_wq; /* single thread work queue */ struct completion llc_confirm; /* wait for rx of conf link */ struct completion llc_confirm_resp; /* wait 4 rx of cnf lnk rsp */ int llc_confirm_rc; /* rc from confirm link msg */ diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c index 5dbeced6cea5..5d7926cc472c 100644 --- a/net/smc/smc_llc.c +++ b/net/smc/smc_llc.c @@ -239,6 +239,25 @@ static int smc_llc_send_confirm_rkey(struct smc_link *link, return rc; } +/* prepare an add link message */ +static void smc_llc_prep_add_link(struct smc_llc_msg_add_link *addllc, + struct smc_link *link, u8 mac[], + union ib_gid *gid, + enum smc_llc_reqresp reqresp) +{ + memset(addllc, 0, sizeof(*addllc)); + addllc->hd.common.type = SMC_LLC_ADD_LINK; + addllc->hd.length = sizeof(struct smc_llc_msg_add_link); + if (reqresp == SMC_LLC_RESP) { + addllc->hd.flags |= SMC_LLC_FLAG_RESP; + /* always reject more links for now */ + addllc->hd.flags |= SMC_LLC_FLAG_ADD_LNK_REJ; + addllc->hd.add_link_rej_rsn = SMC_LLC_REJ_RSN_NO_ALT_PATH; + } + memcpy(addllc->sender_mac, mac, ETH_ALEN); + memcpy(addllc->sender_gid, gid, SMC_GID_SIZE); +} + /* send ADD LINK request or response */ int smc_llc_send_add_link(struct smc_link *link, u8 mac[], union ib_gid *gid, @@ -253,22 +272,28 @@ int smc_llc_send_add_link(struct smc_link *link, u8 mac[], if (rc) return rc; addllc = (struct smc_llc_msg_add_link *)wr_buf; - memset(addllc, 0, sizeof(*addllc)); - addllc->hd.common.type = SMC_LLC_ADD_LINK; - addllc->hd.length = sizeof(struct smc_llc_msg_add_link); - if (reqresp == SMC_LLC_RESP) { - addllc->hd.flags |= SMC_LLC_FLAG_RESP; - /* always reject more links for now */ - addllc->hd.flags |= SMC_LLC_FLAG_ADD_LNK_REJ; - addllc->hd.add_link_rej_rsn = SMC_LLC_REJ_RSN_NO_ALT_PATH; - } - memcpy(addllc->sender_mac, mac, ETH_ALEN); - memcpy(addllc->sender_gid, gid, SMC_GID_SIZE); + smc_llc_prep_add_link(addllc, link, mac, gid, reqresp); /* send llc message */ rc = smc_wr_tx_send(link, pend); return rc; } +/* prepare a delete link message */ +static void smc_llc_prep_delete_link(struct smc_llc_msg_del_link *delllc, + struct smc_link *link, + enum smc_llc_reqresp reqresp) +{ + memset(delllc, 0, sizeof(*delllc)); + delllc->hd.common.type = SMC_LLC_DELETE_LINK; + delllc->hd.length = sizeof(struct smc_llc_msg_add_link); + if (reqresp == SMC_LLC_RESP) + delllc->hd.flags |= SMC_LLC_FLAG_RESP; + /* DEL_LINK_ALL because only 1 link supported */ + delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ALL; + delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY; + delllc->link_num = link->link_id; +} + /* send DELETE LINK request or response */ int smc_llc_send_delete_link(struct smc_link *link, enum smc_llc_reqresp reqresp) @@ -282,15 +307,7 @@ int smc_llc_send_delete_link(struct smc_link *link, if (rc) return rc; delllc = (struct smc_llc_msg_del_link *)wr_buf; - memset(delllc, 0, sizeof(*delllc)); - delllc->hd.common.type = SMC_LLC_DELETE_LINK; - delllc->hd.length = sizeof(struct smc_llc_msg_add_link); - if (reqresp == SMC_LLC_RESP) - delllc->hd.flags |= SMC_LLC_FLAG_RESP; - /* DEL_LINK_ALL because only 1 link supported */ - delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ALL; - delllc->hd.flags |= SMC_LLC_FLAG_DEL_LINK_ORDERLY; - delllc->link_num = link->link_id; + smc_llc_prep_delete_link(delllc, link, reqresp); /* send llc message */ rc = smc_wr_tx_send(link, pend); return rc; @@ -317,20 +334,46 @@ static int smc_llc_send_test_link(struct smc_link *link, u8 user_data[16]) return rc; } -/* send a prepared message */ -static int smc_llc_send_message(struct smc_link *link, void *llcbuf, int llclen) +struct smc_llc_send_work { + struct work_struct work; + struct smc_link *link; + int llclen; + union smc_llc_msg llcbuf; +}; + +/* worker that sends a prepared message */ +static void smc_llc_send_message_work(struct work_struct *work) { + struct smc_llc_send_work *llcwrk = container_of(work, + struct smc_llc_send_work, work); struct smc_wr_tx_pend_priv *pend; struct smc_wr_buf *wr_buf; int rc; - rc = smc_llc_add_pending_send(link, &wr_buf, &pend); + if (llcwrk->link->state == SMC_LNK_INACTIVE) + goto out; + rc = smc_llc_add_pending_send(llcwrk->link, &wr_buf, &pend); if (rc) - return rc; - memcpy(wr_buf, llcbuf, llclen); - /* send llc message */ - rc = smc_wr_tx_send(link, pend); - return rc; + goto out; + memcpy(wr_buf, &llcwrk->llcbuf, llcwrk->llclen); + smc_wr_tx_send(llcwrk->link, pend); +out: + kfree(llcwrk); +} + +/* copy llcbuf and schedule an llc send on link */ +static int smc_llc_send_message(struct smc_link *link, void *llcbuf, int llclen) +{ + struct smc_llc_send_work *wrk = kmalloc(sizeof(*wrk), GFP_ATOMIC); + + if (!wrk) + return -ENOMEM; + INIT_WORK(&wrk->work, smc_llc_send_message_work); + wrk->link = link; + wrk->llclen = llclen; + memcpy(&wrk->llcbuf, llcbuf, llclen); + queue_work(link->llc_wq, &wrk->work); + return 0; } /********************************* receive ***********************************/ @@ -381,17 +424,18 @@ static void smc_llc_rx_add_link(struct smc_link *link, } if (lgr->role == SMC_SERV) { - smc_llc_send_add_link(link, + smc_llc_prep_add_link(llc, link, link->smcibdev->mac[link->ibport - 1], &link->smcibdev->gid[link->ibport - 1], SMC_LLC_REQ); } else { - smc_llc_send_add_link(link, + smc_llc_prep_add_link(llc, link, link->smcibdev->mac[link->ibport - 1], &link->smcibdev->gid[link->ibport - 1], SMC_LLC_RESP); } + smc_llc_send_message(link, llc, sizeof(*llc)); } } @@ -407,9 +451,11 @@ static void smc_llc_rx_delete_link(struct smc_link *link, } else { if (lgr->role == SMC_SERV) { smc_lgr_forget(lgr); - smc_llc_send_delete_link(link, SMC_LLC_REQ); + smc_llc_prep_delete_link(llc, link, SMC_LLC_REQ); + smc_llc_send_message(link, llc, sizeof(*llc)); } else { - smc_llc_send_delete_link(link, SMC_LLC_RESP); + smc_llc_prep_delete_link(llc, link, SMC_LLC_RESP); + smc_llc_send_message(link, llc, sizeof(*llc)); smc_lgr_terminate(lgr); } } @@ -559,11 +605,19 @@ static void smc_llc_testlink_work(struct work_struct *work) } next_interval = link->llc_testlink_time; out: - schedule_delayed_work(&link->llc_testlink_wrk, next_interval); + queue_delayed_work(link->llc_wq, &link->llc_testlink_wrk, + next_interval); } -void smc_llc_link_init(struct smc_link *link) +int smc_llc_link_init(struct smc_link *link) { + struct smc_link_group *lgr = container_of(link, struct smc_link_group, + lnk[SMC_SINGLE_LINK]); + link->llc_wq = alloc_ordered_workqueue("llc_wq-%x:%x)", WQ_MEM_RECLAIM, + *((u32 *)lgr->id), + link->link_id); + if (!link->llc_wq) + return -ENOMEM; init_completion(&link->llc_confirm); init_completion(&link->llc_confirm_resp); init_completion(&link->llc_add); @@ -571,6 +625,7 @@ void smc_llc_link_init(struct smc_link *link) init_completion(&link->llc_confirm_rkey); init_completion(&link->llc_testlink_resp); INIT_DELAYED_WORK(&link->llc_testlink_wrk, smc_llc_testlink_work); + return 0; } void smc_llc_link_active(struct smc_link *link, int testlink_time) @@ -578,8 +633,8 @@ void smc_llc_link_active(struct smc_link *link, int testlink_time) link->state = SMC_LNK_ACTIVE; if (testlink_time) { link->llc_testlink_time = testlink_time * HZ; - schedule_delayed_work(&link->llc_testlink_wrk, - link->llc_testlink_time); + queue_delayed_work(link->llc_wq, &link->llc_testlink_wrk, + link->llc_testlink_time); } } @@ -591,9 +646,10 @@ void smc_llc_link_inactive(struct smc_link *link) } /* called in worker context */ -void smc_llc_link_flush(struct smc_link *link) +void smc_llc_link_clear(struct smc_link *link) { - cancel_delayed_work_sync(&link->llc_testlink_wrk); + flush_workqueue(link->llc_wq); + destroy_workqueue(link->llc_wq); } /* register a new rtoken at the remote peer */ diff --git a/net/smc/smc_llc.h b/net/smc/smc_llc.h index d7f52a60c8d6..65c8645e96a1 100644 --- a/net/smc/smc_llc.h +++ b/net/smc/smc_llc.h @@ -42,10 +42,10 @@ int smc_llc_send_add_link(struct smc_link *link, u8 mac[], union ib_gid *gid, enum smc_llc_reqresp reqresp); int smc_llc_send_delete_link(struct smc_link *link, enum smc_llc_reqresp reqresp); -void smc_llc_link_init(struct smc_link *link); +int smc_llc_link_init(struct smc_link *link); void smc_llc_link_active(struct smc_link *link, int testlink_time); void smc_llc_link_inactive(struct smc_link *link); -void smc_llc_link_flush(struct smc_link *link); +void smc_llc_link_clear(struct smc_link *link); int smc_llc_do_confirm_rkey(struct smc_link *link, struct smc_buf_desc *rmb_desc); int smc_llc_init(void) __init; -- cgit v1.2.1