From patchwork Mon Jul 24 10:53:00 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Thomas Gleixner X-Patchwork-Id: 9859217 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 18857600F5 for ; Mon, 24 Jul 2017 10:56:07 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 0B92B283FD for ; Mon, 24 Jul 2017 10:56:07 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id 005182857E; Mon, 24 Jul 2017 10:56:06 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id A240B283FD for ; Mon, 24 Jul 2017 10:56:06 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753367AbdGXKzV (ORCPT ); Mon, 24 Jul 2017 06:55:21 -0400 Received: from Galois.linutronix.de ([146.0.238.70]:35092 "EHLO Galois.linutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751649AbdGXKzP (ORCPT ); Mon, 24 Jul 2017 06:55:15 -0400 Received: from localhost ([127.0.0.1] helo=[127.0.1.1]) by Galois.linutronix.de with esmtp (Exim 4.80) (envelope-from ) id 1dZb0j-0002zx-Bs; Mon, 24 Jul 2017 12:54:49 +0200 Message-Id: <20170724105341.629655637@linutronix.de> User-Agent: quilt/0.63-1 Date: Mon, 24 Jul 2017 12:53:00 +0200 From: Thomas Gleixner To: LKML Cc: QLogic-Storage-Upstream@qlogic.com, martin.petersen@oracle.com, James Bottomley , linux-scsi , Christoph Hellwig , Sebastian Andrzej Siewior Subject: [patch 5/5] scsi/bnx2i: Simplify cpu hotplug code References: <20170724105255.715647116@linutronix.de> MIME-Version: 1.0 Content-Disposition: inline; filename=scsci-bxn2i--Simplify-cpu-hotplug-code.patch Sender: linux-scsi-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-scsi@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The CPU hotplug related code of this driver can be simplified by: 1) Consolidating the callbacks into a single state. The CPU thread can be torn down on the CPU which goes offline. There is no point in delaying that to the CPU dead state 2) Let the core code invoke the online/offline callbacks and remove the extra for_each_online_cpu() loops. Signed-off-by: Thomas Gleixner --- drivers/scsi/bnx2i/bnx2i_init.c | 65 +++++++++------------------------------- include/linux/cpuhotplug.h | 1 2 files changed, 15 insertions(+), 51 deletions(-) --- a/drivers/scsi/bnx2i/bnx2i_init.c +++ b/drivers/scsi/bnx2i/bnx2i_init.c @@ -404,12 +404,11 @@ int bnx2i_get_stats(void *handle) /** - * bnx2i_percpu_thread_create - Create a receive thread for an - * online CPU + * bnx2i_cpu_online - Create a receive thread for an online CPU * * @cpu: cpu index for the online cpu */ -static void bnx2i_percpu_thread_create(unsigned int cpu) +static int bnx2i_cpu_online(unsigned int cpu) { struct bnx2i_percpu_s *p; struct task_struct *thread; @@ -419,16 +418,17 @@ static void bnx2i_percpu_thread_create(u thread = kthread_create_on_node(bnx2i_percpu_io_thread, (void *)p, cpu_to_node(cpu), "bnx2i_thread/%d", cpu); + if (IS_ERR(thread)) + return PTR_ERR(thread); + /* bind thread to the cpu */ - if (likely(!IS_ERR(thread))) { - kthread_bind(thread, cpu); - p->iothread = thread; - wake_up_process(thread); - } + kthread_bind(thread, cpu); + p->iothread = thread; + wake_up_process(thread); + return 0; } - -static void bnx2i_percpu_thread_destroy(unsigned int cpu) +static int bnx2i_cpu_offline(unsigned int cpu) { struct bnx2i_percpu_s *p; struct task_struct *thread; @@ -451,19 +451,6 @@ static void bnx2i_percpu_thread_destroy( spin_unlock_bh(&p->p_work_lock); if (thread) kthread_stop(thread); -} - -static int bnx2i_cpu_online(unsigned int cpu) -{ - pr_info("bnx2i: CPU %x online: Create Rx thread\n", cpu); - bnx2i_percpu_thread_create(cpu); - return 0; -} - -static int bnx2i_cpu_dead(unsigned int cpu) -{ - pr_info("CPU %x offline: Remove Rx thread\n", cpu); - bnx2i_percpu_thread_destroy(cpu); return 0; } @@ -511,28 +498,14 @@ static int __init bnx2i_mod_init(void) p->iothread = NULL; } - get_online_cpus(); - - for_each_online_cpu(cpu) - bnx2i_percpu_thread_create(cpu); - - err = cpuhp_setup_state_nocalls_cpuslocked(CPUHP_AP_ONLINE_DYN, - "scsi/bnx2i:online", - bnx2i_cpu_online, NULL); + err = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "scsi/bnx2i:online", + bnx2i_cpu_online, bnx2i_cpu_offline); if (err < 0) - goto remove_threads; + goto unreg_driver; bnx2i_online_state = err; - - cpuhp_setup_state_nocalls_cpuslocked(CPUHP_SCSI_BNX2I_DEAD, - "scsi/bnx2i:dead", - NULL, bnx2i_cpu_dead); - put_online_cpus(); return 0; -remove_threads: - for_each_online_cpu(cpu) - bnx2i_percpu_thread_destroy(cpu); - put_online_cpus(); +unreg_driver: cnic_unregister_driver(CNIC_ULP_ISCSI); unreg_xport: iscsi_unregister_transport(&bnx2i_iscsi_transport); @@ -552,7 +525,6 @@ static int __init bnx2i_mod_init(void) static void __exit bnx2i_mod_exit(void) { struct bnx2i_hba *hba; - unsigned cpu = 0; mutex_lock(&bnx2i_dev_lock); while (!list_empty(&adapter_list)) { @@ -570,14 +542,7 @@ static void __exit bnx2i_mod_exit(void) } mutex_unlock(&bnx2i_dev_lock); - get_online_cpus(); - - for_each_online_cpu(cpu) - bnx2i_percpu_thread_destroy(cpu); - - cpuhp_remove_state_nocalls_cpuslocked(bnx2i_online_state); - cpuhp_remove_state_nocalls_cpuslocked(CPUHP_SCSI_BNX2I_DEAD); - put_online_cpus(); + cpuhp_remove_state(bnx2i_online_state); iscsi_unregister_transport(&bnx2i_iscsi_transport); cnic_unregister_driver(CNIC_ULP_ISCSI); --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -39,7 +39,6 @@ enum cpuhp_state { CPUHP_PCI_XGENE_DEAD, CPUHP_IOMMU_INTEL_DEAD, CPUHP_LUSTRE_CFS_DEAD, - CPUHP_SCSI_BNX2I_DEAD, CPUHP_WORKQUEUE_PREP, CPUHP_POWER_NUMA_PREPARE, CPUHP_HRTIMERS_PREPARE,