From: Mike Marciniszyn Date: Tue, 4 Jun 2013 19:05:37 +0000 (-0400) Subject: IB/qib: Optimize CQ callbacks X-Git-Tag: v3.11-rc1~16^2~1^6~4 X-Git-Url: http://git.agner.ch/gitweb/?p=linux.git;a=commitdiff_plain;h=85caafe307a06e4f9993c8f3c994a07374c07831 IB/qib: Optimize CQ callbacks The current workqueue implemention has the following performance deficiencies on QDR HCAs: - The CQ call backs tend to run on the CPUs processing the receive queues - The single thread queue isn't optimal for multiple HCAs This patch adds a dedicated per HCA bound thread to process CQ callbacks. Reviewed-by: Ramkrishna Vepa Signed-off-by: Mike Marciniszyn Signed-off-by: Roland Dreier --- diff --git a/drivers/infiniband/hw/qib/qib.h b/drivers/infiniband/hw/qib/qib.h index 2ee82e6550c7..3a78b92cbd4e 100644 --- a/drivers/infiniband/hw/qib/qib.h +++ b/drivers/infiniband/hw/qib/qib.h @@ -1,7 +1,7 @@ #ifndef _QIB_KERNEL_H #define _QIB_KERNEL_H /* - * Copyright (c) 2012 Intel Corporation. All rights reserved. + * Copyright (c) 2012, 2013 Intel Corporation. All rights reserved. * Copyright (c) 2006 - 2012 QLogic Corporation. All rights reserved. * Copyright (c) 2003, 2004, 2005, 2006 PathScale, Inc. All rights reserved. * @@ -51,6 +51,7 @@ #include #include #include +#include #include "qib_common.h" #include "qib_verbs.h" @@ -1090,6 +1091,8 @@ struct qib_devdata { u16 psxmitwait_check_rate; /* high volume overflow errors defered to tasklet */ struct tasklet_struct error_tasklet; + /* per device cq worker */ + struct kthread_worker *worker; int assigned_node_id; /* NUMA node closest to HCA */ }; diff --git a/drivers/infiniband/hw/qib/qib_cq.c b/drivers/infiniband/hw/qib/qib_cq.c index 5246aa486bbe..ab4e11cfab15 100644 --- a/drivers/infiniband/hw/qib/qib_cq.c +++ b/drivers/infiniband/hw/qib/qib_cq.c @@ -1,4 +1,5 @@ /* + * Copyright (c) 2013 Intel Corporation. All rights reserved. * Copyright (c) 2006, 2007, 2008, 2010 QLogic Corporation. All rights reserved. * Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved. * @@ -34,8 +35,10 @@ #include #include #include +#include #include "qib_verbs.h" +#include "qib.h" /** * qib_cq_enter - add a new entry to the completion queue @@ -102,13 +105,18 @@ void qib_cq_enter(struct qib_cq *cq, struct ib_wc *entry, int solicited) if (cq->notify == IB_CQ_NEXT_COMP || (cq->notify == IB_CQ_SOLICITED && (solicited || entry->status != IB_WC_SUCCESS))) { - cq->notify = IB_CQ_NONE; - cq->triggered++; + struct kthread_worker *worker; /* * This will cause send_complete() to be called in * another thread. */ - queue_work(qib_cq_wq, &cq->comptask); + smp_rmb(); + worker = cq->dd->worker; + if (likely(worker)) { + cq->notify = IB_CQ_NONE; + cq->triggered++; + queue_kthread_work(worker, &cq->comptask); + } } spin_unlock_irqrestore(&cq->lock, flags); @@ -163,7 +171,7 @@ bail: return npolled; } -static void send_complete(struct work_struct *work) +static void send_complete(struct kthread_work *work) { struct qib_cq *cq = container_of(work, struct qib_cq, comptask); @@ -287,11 +295,12 @@ struct ib_cq *qib_create_cq(struct ib_device *ibdev, int entries, * The number of entries should be >= the number requested or return * an error. */ + cq->dd = dd_from_dev(dev); cq->ibcq.cqe = entries; cq->notify = IB_CQ_NONE; cq->triggered = 0; spin_lock_init(&cq->lock); - INIT_WORK(&cq->comptask, send_complete); + init_kthread_work(&cq->comptask, send_complete); wc->head = 0; wc->tail = 0; cq->queue = wc; @@ -323,7 +332,7 @@ int qib_destroy_cq(struct ib_cq *ibcq) struct qib_ibdev *dev = to_idev(ibcq->device); struct qib_cq *cq = to_icq(ibcq); - flush_work(&cq->comptask); + flush_kthread_work(&cq->comptask); spin_lock(&dev->n_cqs_lock); dev->n_cqs_allocated--; spin_unlock(&dev->n_cqs_lock); @@ -483,3 +492,49 @@ bail_free: bail: return ret; } + +int qib_cq_init(struct qib_devdata *dd) +{ + int ret = 0; + int cpu; + struct task_struct *task; + + if (dd->worker) + return 0; + dd->worker = kzalloc(sizeof(*dd->worker), GFP_KERNEL); + if (!dd->worker) + return -ENOMEM; + init_kthread_worker(dd->worker); + task = kthread_create_on_node( + kthread_worker_fn, + dd->worker, + dd->assigned_node_id, + "qib_cq%d", dd->unit); + if (IS_ERR(task)) + goto task_fail; + cpu = cpumask_first(cpumask_of_node(dd->assigned_node_id)); + kthread_bind(task, cpu); + wake_up_process(task); +out: + return ret; +task_fail: + ret = PTR_ERR(task); + kfree(dd->worker); + dd->worker = NULL; + goto out; +} + +void qib_cq_exit(struct qib_devdata *dd) +{ + struct kthread_worker *worker; + + worker = dd->worker; + if (!worker) + return; + /* blocks future queuing from send_complete() */ + dd->worker = NULL; + smp_wmb(); + flush_kthread_worker(worker); + kthread_stop(worker->task); + kfree(worker); +} diff --git a/drivers/infiniband/hw/qib/qib_init.c b/drivers/infiniband/hw/qib/qib_init.c index e02217b5c46d..ff36903474ea 100644 --- a/drivers/infiniband/hw/qib/qib_init.c +++ b/drivers/infiniband/hw/qib/qib_init.c @@ -97,8 +97,6 @@ unsigned qib_wc_pat = 1; /* default (1) is to use PAT, not MTRR */ module_param_named(wc_pat, qib_wc_pat, uint, S_IRUGO); MODULE_PARM_DESC(wc_pat, "enable write-combining via PAT mechanism"); -struct workqueue_struct *qib_cq_wq; - static void verify_interrupt(unsigned long); static struct idr qib_unit_table; @@ -445,6 +443,7 @@ static int loadtime_init(struct qib_devdata *dd) dd->intrchk_timer.function = verify_interrupt; dd->intrchk_timer.data = (unsigned long) dd; + ret = qib_cq_init(dd); done: return ret; } @@ -1215,12 +1214,6 @@ static int __init qlogic_ib_init(void) if (ret) goto bail; - qib_cq_wq = create_singlethread_workqueue("qib_cq"); - if (!qib_cq_wq) { - ret = -ENOMEM; - goto bail_dev; - } - /* * These must be called before the driver is registered with * the PCI subsystem. @@ -1233,7 +1226,7 @@ static int __init qlogic_ib_init(void) ret = pci_register_driver(&qib_driver); if (ret < 0) { pr_err("Unable to register driver: error %d\n", -ret); - goto bail_unit; + goto bail_dev; } /* not fatal if it doesn't work */ @@ -1241,13 +1234,11 @@ static int __init qlogic_ib_init(void) pr_err("Unable to register ipathfs\n"); goto bail; /* all OK */ -bail_unit: +bail_dev: #ifdef CONFIG_INFINIBAND_QIB_DCA dca_unregister_notify(&dca_notifier); #endif idr_destroy(&qib_unit_table); - destroy_workqueue(qib_cq_wq); -bail_dev: qib_dev_cleanup(); bail: return ret; @@ -1273,8 +1264,6 @@ static void __exit qlogic_ib_cleanup(void) #endif pci_unregister_driver(&qib_driver); - destroy_workqueue(qib_cq_wq); - qib_cpulist_count = 0; kfree(qib_cpulist); @@ -1365,6 +1354,7 @@ static void cleanup_device_data(struct qib_devdata *dd) } kfree(tmp); kfree(dd->boardname); + qib_cq_exit(dd); } /* diff --git a/drivers/infiniband/hw/qib/qib_verbs.h b/drivers/infiniband/hw/qib/qib_verbs.h index aff8b2c17886..86c2cb3c9caf 100644 --- a/drivers/infiniband/hw/qib/qib_verbs.h +++ b/drivers/infiniband/hw/qib/qib_verbs.h @@ -41,6 +41,7 @@ #include #include #include +#include #include #include #include @@ -267,7 +268,8 @@ struct qib_cq_wc { */ struct qib_cq { struct ib_cq ibcq; - struct work_struct comptask; + struct kthread_work comptask; + struct qib_devdata *dd; spinlock_t lock; /* protect changes in this struct */ u8 notify; u8 triggered; @@ -832,8 +834,6 @@ static inline int qib_send_ok(struct qib_qp *qp) !(qp->s_flags & QIB_S_ANY_WAIT_SEND)); } -extern struct workqueue_struct *qib_cq_wq; - /* * This must be called with s_lock held. */ @@ -972,6 +972,10 @@ int qib_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr); int qib_destroy_srq(struct ib_srq *ibsrq); +int qib_cq_init(struct qib_devdata *dd); + +void qib_cq_exit(struct qib_devdata *dd); + void qib_cq_enter(struct qib_cq *cq, struct ib_wc *entry, int sig); int qib_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *entry);