From patchwork Thu Aug 11 15:37:38 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jinhao Fan X-Patchwork-Id: 12941568 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from lists.gnu.org (lists.gnu.org [209.51.188.17]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 9634EC25B0C for ; Thu, 11 Aug 2022 15:43:10 +0000 (UTC) Received: from localhost ([::1]:47418 helo=lists1p.gnu.org) by lists.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oMAKz-0001VL-Np for qemu-devel@archiver.kernel.org; Thu, 11 Aug 2022 11:43:09 -0400 Received: from eggs.gnu.org ([2001:470:142:3::10]:50402) by lists.gnu.org with esmtps (TLS1.2:ECDHE_RSA_AES_256_GCM_SHA384:256) (Exim 4.90_1) (envelope-from ) id 1oMAGS-00036x-6u; Thu, 11 Aug 2022 11:38:28 -0400 Received: from smtp21.cstnet.cn ([159.226.251.21]:49842 helo=cstnet.cn) by eggs.gnu.org with esmtp (Exim 4.90_1) (envelope-from ) id 1oMAGP-00027h-0T; Thu, 11 Aug 2022 11:38:27 -0400 Received: from localhost.localdomain (unknown [159.226.43.62]) by APP-01 (Coremail) with SMTP id qwCowAA3GFlSIvViGUPiBw--.35837S5; Thu, 11 Aug 2022 23:38:20 +0800 (CST) From: Jinhao Fan To: qemu-devel@nongnu.org Cc: its@irrelevant.dk, kbusch@kernel.org, stefanha@gmail.com, Jinhao Fan , qemu-block@nongnu.org (open list:nvme) Subject: [PATCH 3/4] hw/nvme: use irqfd to send interrupts Date: Thu, 11 Aug 2022 23:37:38 +0800 Message-Id: <20220811153739.3079672-4-fanjinhao21s@ict.ac.cn> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20220811153739.3079672-1-fanjinhao21s@ict.ac.cn> References: <20220811153739.3079672-1-fanjinhao21s@ict.ac.cn> MIME-Version: 1.0 X-CM-TRANSID: qwCowAA3GFlSIvViGUPiBw--.35837S5 X-Coremail-Antispam: 1UD129KBjvJXoWxCw43AF17Kw1xJr4kuF1UGFg_yoWrXr48pa 4kGrZ5CF4vy34xWa1avrsrAr1ru3y8tryUJ3ySkry7Arn5Kr9xArW8CF1UtFy8Jr98XFy5 ZrsFqr4Uua45XaUanT9S1TB71UUUUUUqnTZGkaVYY2UrUUUUjbIjqfuFe4nvWSU5nxnvy2 9KBjDU0xBIdaVrnRJUUUBC14x267AKxVWrJVCq3wAFc2x0x2IEx4CE42xK8VAvwI8IcIk0 rVWrJVCq3wAFIxvE14AKwVWUJVWUGwA2048vs2IY020E87I2jVAFwI0_JrWl82xGYIkIc2 x26xkF7I0E14v26r4j6ryUM28lY4IEw2IIxxk0rwA2F7IY1VAKz4vEj48ve4kI8wA2z4x0 Y4vE2Ix0cI8IcVAFwI0_JFI_Gr1l84ACjcxK6xIIjxv20xvEc7CjxVAFwI0_Gr0_Cr1l84 ACjcxK6I8E87Iv67AKxVWxJr0_GcWl84ACjcxK6I8E87Iv6xkF7I0E14v26rxl6s0DM2AI xVAIcxkEcVAq07x20xvEncxIr21l5I8CrVACY4xI64kE6c02F40Ex7xfMcIj6xIIjxv20x vE14v26r1j6r18McIj6I8E87Iv67AKxVWxJVW8Jr1lOx8S6xCaFVCjc4AY6r1j6r4UM4x0 Y48IcxkI7VAKI48JM4x0x7Aq67IIx4CEVc8vx2IErcIFxwCY1x0264kExVAvwVAq07x20x yl42xK82IYc2Ij64vIr41l4I8I3I0E4IkC6x0Yz7v_Jr0_Gr1lx2IqxVAqx4xG67AKxVWU JVWUGwC20s026x8GjcxK67AKxVWUGVWUWwC2zVAF1VAY17CE14v26r126r1DMIIYrxkI7V AKI48JMIIF0xvE2Ix0cI8IcVAFwI0_Jr0_JF4lIxAIcVC0I7IYx2IY6xkF7I0E14v26r4j 6F4UMIIF0xvE42xK8VAvwI8IcIk0rVWUJVWUCwCI42IY6I8E87Iv67AKxVWUJVW8JwCI42 IY6I8E87Iv6xkF7I0E14v26r4j6r4UJbIYCTnIWIevJa73UjIFyTuYvjfUUdb1DUUUU X-Originating-IP: [159.226.43.62] X-CM-SenderInfo: xidqyxpqkd0j0rv6xunwoduhdfq/ Received-SPF: pass client-ip=159.226.251.21; envelope-from=fanjinhao21s@ict.ac.cn; helo=cstnet.cn X-Spam_score_int: -41 X-Spam_score: -4.2 X-Spam_bar: ---- X-Spam_report: (-4.2 / 5.0 requ) BAYES_00=-1.9, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, T_SCC_BODY_TEXT_LINE=-0.01 autolearn=ham autolearn_force=no X-Spam_action: no action X-BeenThere: qemu-devel@nongnu.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: qemu-devel-bounces+qemu-devel=archiver.kernel.org@nongnu.org Sender: "Qemu-devel" Use KVM's irqfd to send interrupts when possible. This approach is thread safe. Moreover, it does not have the inter-thread communication overhead of plain event notifiers since handler callback are called in the same system call as irqfd write. Signed-off-by: Jinhao Fan --- hw/nvme/ctrl.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++-- hw/nvme/nvme.h | 1 + 2 files changed, 49 insertions(+), 2 deletions(-) diff --git a/hw/nvme/ctrl.c b/hw/nvme/ctrl.c index 8a1c5ce3e1..63f988f2f9 100644 --- a/hw/nvme/ctrl.c +++ b/hw/nvme/ctrl.c @@ -192,6 +192,7 @@ #include "qapi/error.h" #include "qapi/visitor.h" #include "sysemu/sysemu.h" +#include "sysemu/kvm.h" #include "sysemu/block-backend.h" #include "sysemu/hostmem.h" #include "hw/pci/msix.h" @@ -1354,8 +1355,26 @@ static void nvme_deassert_notifier_read(EventNotifier *e) } } +static int nvme_kvm_msix_vector_use(NvmeCtrl *n, + NvmeCQueue *cq, + uint32_t vector) +{ + int ret; + + KVMRouteChange c = kvm_irqchip_begin_route_changes(kvm_state); + ret = kvm_irqchip_add_msi_route(&c, vector, &n->parent_obj); + if (ret < 0) { + return ret; + } + kvm_irqchip_commit_route_changes(&c); + cq->virq = ret; + return 0; +} + static void nvme_init_irq_notifier(NvmeCtrl *n, NvmeCQueue *cq) { + bool with_irqfd = msix_enabled(&n->parent_obj) && + kvm_msi_via_irqfd_enabled(); int ret; ret = event_notifier_init(&cq->assert_notifier, 0); @@ -1363,8 +1382,21 @@ static void nvme_init_irq_notifier(NvmeCtrl *n, NvmeCQueue *cq) goto fail_assert_handler; } - event_notifier_set_handler(&cq->assert_notifier, - nvme_assert_notifier_read); + if (with_irqfd) { + ret = nvme_kvm_msix_vector_use(n, cq, cq->vector); + if (ret < 0) { + goto fail_assert_handler; + } + ret = kvm_irqchip_add_irqfd_notifier_gsi(kvm_state, + &cq->assert_notifier, NULL, + cq->virq); + if (ret < 0) { + goto fail_kvm; + } + } else { + event_notifier_set_handler(&cq->assert_notifier, + nvme_assert_notifier_read); + } if (!msix_enabled(&n->parent_obj)) { ret = event_notifier_init(&cq->deassert_notifier, 0); @@ -1381,6 +1413,12 @@ static void nvme_init_irq_notifier(NvmeCtrl *n, NvmeCQueue *cq) fail_deassert_handler: event_notifier_set_handler(&cq->deassert_notifier, NULL); event_notifier_cleanup(&cq->deassert_notifier); + if (with_irqfd) { + kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, &cq->assert_notifier, + cq->virq); +fail_kvm: + kvm_irqchip_release_virq(kvm_state, cq->virq); + } fail_assert_handler: event_notifier_set_handler(&cq->assert_notifier, NULL); event_notifier_cleanup(&cq->assert_notifier); @@ -4764,6 +4802,8 @@ static uint16_t nvme_get_log(NvmeCtrl *n, NvmeRequest *req) static void nvme_free_cq(NvmeCQueue *cq, NvmeCtrl *n) { + bool with_irqfd = msix_enabled(&n->parent_obj) && + kvm_msi_via_irqfd_enabled(); uint16_t offset = (cq->cqid << 3) + (1 << 2); n->cq[cq->cqid] = NULL; @@ -4775,6 +4815,12 @@ static void nvme_free_cq(NvmeCQueue *cq, NvmeCtrl *n) event_notifier_cleanup(&cq->notifier); } if (cq->assert_notifier.initialized) { + if (with_irqfd) { + kvm_irqchip_remove_irqfd_notifier_gsi(kvm_state, + &cq->assert_notifier, + cq->virq); + kvm_irqchip_release_virq(kvm_state, cq->virq); + } event_notifier_set_handler(&cq->assert_notifier, NULL); event_notifier_cleanup(&cq->assert_notifier); } diff --git a/hw/nvme/nvme.h b/hw/nvme/nvme.h index 759d0ecd7c..85fd9cd0e2 100644 --- a/hw/nvme/nvme.h +++ b/hw/nvme/nvme.h @@ -396,6 +396,7 @@ typedef struct NvmeCQueue { uint64_t dma_addr; uint64_t db_addr; uint64_t ei_addr; + int virq; QEMUTimer *timer; EventNotifier notifier; EventNotifier assert_notifier;