From patchwork Tue Apr 20 19:00:34 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Jiang X-Patchwork-Id: 12214981 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id B05E3C433B4 for ; Tue, 20 Apr 2021 19:00:53 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 7E8C8613C9 for ; Tue, 20 Apr 2021 19:00:53 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233632AbhDTTBY (ORCPT ); Tue, 20 Apr 2021 15:01:24 -0400 Received: from mga02.intel.com ([134.134.136.20]:12161 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233498AbhDTTBX (ORCPT ); Tue, 20 Apr 2021 15:01:23 -0400 IronPort-SDR: dd8LqYho14Mba34Cl7zJ1GjcoWHN3W3m+ceT2sS2oI1rklC3Hi1ey6WoKVSQMto7eHVtWP+e+a 8uhYrpByBe3Q== X-IronPort-AV: E=McAfee;i="6200,9189,9960"; a="182701622" X-IronPort-AV: E=Sophos;i="5.82,237,1613462400"; d="scan'208";a="182701622" Received: from orsmga008.jf.intel.com ([10.7.209.65]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Apr 2021 12:00:36 -0700 IronPort-SDR: mul3YQHkpRQRhVWWoanA/HREB8oxZVeXgST84DWtG3vEaAvM4vR8ak+l4HYKJ1a8DixhgXLrto PRIm+U+40J8Q== X-IronPort-AV: E=Sophos;i="5.82,237,1613462400"; d="scan'208";a="427108456" Received: from djiang5-desk3.ch.intel.com ([143.182.136.137]) by orsmga008-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Apr 2021 12:00:36 -0700 Subject: [PATCH] dmaengine: idxd: remove MSIX masking for interrupt handlers From: Dave Jiang To: vkoul@kernel.org Cc: Dan Williams , Dan Williams , dmaengine@vger.kernel.org Date: Tue, 20 Apr 2021 12:00:34 -0700 Message-ID: <161894523436.3210025.1834640110556139277.stgit@djiang5-desk3.ch.intel.com> User-Agent: StGit/0.23-29-ga622f1 MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: dmaengine@vger.kernel.org Remove interrupt masking and just let the hard irq handler keep firing for new events. This is less of a performance impact vs the MMIO readback inside the pci_msi_{mask,unmas}_irq(). Especially with a loaded system those flushes can be stuck behind large amounts of MMIO writes to flush. When guest kernel is running on top of VFIO mdev, mask/unmask causes a vmexit each time and is not desirable. Suggested-by: Dan Williams Signed-off-by: Dave Jiang Reviewed-by: Dan Williams --- drivers/dma/idxd/idxd.h | 1 - drivers/dma/idxd/init.c | 4 ++-- drivers/dma/idxd/irq.c | 12 ------------ 3 files changed, 2 insertions(+), 15 deletions(-) diff --git a/drivers/dma/idxd/idxd.h b/drivers/dma/idxd/idxd.h index d7185c6bfade..7237f3e15a5e 100644 --- a/drivers/dma/idxd/idxd.h +++ b/drivers/dma/idxd/idxd.h @@ -376,7 +376,6 @@ void idxd_wqs_quiesce(struct idxd_device *idxd); /* device interrupt control */ void idxd_msix_perm_setup(struct idxd_device *idxd); void idxd_msix_perm_clear(struct idxd_device *idxd); -irqreturn_t idxd_irq_handler(int vec, void *data); irqreturn_t idxd_misc_thread(int vec, void *data); irqreturn_t idxd_wq_thread(int irq, void *data); void idxd_mask_error_interrupts(struct idxd_device *idxd); diff --git a/drivers/dma/idxd/init.c b/drivers/dma/idxd/init.c index e6bfd55e421b..36b33eef5aa2 100644 --- a/drivers/dma/idxd/init.c +++ b/drivers/dma/idxd/init.c @@ -102,7 +102,7 @@ static int idxd_setup_interrupts(struct idxd_device *idxd) } irq_entry = &idxd->irq_entries[0]; - rc = request_threaded_irq(irq_entry->vector, idxd_irq_handler, idxd_misc_thread, + rc = request_threaded_irq(irq_entry->vector, NULL, idxd_misc_thread, 0, "idxd-misc", irq_entry); if (rc < 0) { dev_err(dev, "Failed to allocate misc interrupt.\n"); @@ -119,7 +119,7 @@ static int idxd_setup_interrupts(struct idxd_device *idxd) init_llist_head(&idxd->irq_entries[i].pending_llist); INIT_LIST_HEAD(&idxd->irq_entries[i].work_list); - rc = request_threaded_irq(irq_entry->vector, idxd_irq_handler, + rc = request_threaded_irq(irq_entry->vector, NULL, idxd_wq_thread, 0, "idxd-portal", irq_entry); if (rc < 0) { dev_err(dev, "Failed to allocate irq %d.\n", irq_entry->vector); diff --git a/drivers/dma/idxd/irq.c b/drivers/dma/idxd/irq.c index 43eea5c9cbd4..afee571e0194 100644 --- a/drivers/dma/idxd/irq.c +++ b/drivers/dma/idxd/irq.c @@ -102,15 +102,6 @@ static int idxd_device_schedule_fault_process(struct idxd_device *idxd, return 0; } -irqreturn_t idxd_irq_handler(int vec, void *data) -{ - struct idxd_irq_entry *irq_entry = data; - struct idxd_device *idxd = irq_entry->idxd; - - idxd_mask_msix_vector(idxd, irq_entry->id); - return IRQ_WAKE_THREAD; -} - static int process_misc_interrupts(struct idxd_device *idxd, u32 cause) { struct device *dev = &idxd->pdev->dev; @@ -237,7 +228,6 @@ irqreturn_t idxd_misc_thread(int vec, void *data) iowrite32(cause, idxd->reg_base + IDXD_INTCAUSE_OFFSET); } - idxd_unmask_msix_vector(idxd, irq_entry->id); return IRQ_HANDLED; } @@ -394,8 +384,6 @@ irqreturn_t idxd_wq_thread(int irq, void *data) int processed; processed = idxd_desc_process(irq_entry); - idxd_unmask_msix_vector(irq_entry->idxd, irq_entry->id); - if (processed == 0) return IRQ_NONE;