From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pg1-f202.google.com (mail-pg1-f202.google.com [209.85.215.202]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 3BEB01C32 for ; Sat, 17 Aug 2024 00:32:37 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.215.202 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723854760; cv=none; b=guQoyqUkQTOVo/pMPWzQNXnJ1erm7/RxQqUMr8dU0exQazsj0V0ShiYiyY0+OKxELBTWldJjNt9JFbyATqjgZUO9gex6kKotsWaJjqMUq3vzHXiNxFTOgsXl9W+CyJHq8HLEs4OYcEKH4L0UwuRDDrM3oZFtzEyKRCRaM7pgO0g= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1723854760; c=relaxed/simple; bh=qvnyY0A85VDtqWxqSsWJnJnceTfmZS4IyLgE9yBOTBo=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=Eez74n0VCiuJPpyfem7FPPIrZBS72nV31sIP5AhDFMJEKt2M7V8F7Rb3cMZBZS6Bfi53ASwcSTlVl7t3nAz618lxzucWyVJJJiiBLnPKMXuaHNOTHl49ua5K5B6ETyqRzlR/sGN0vUu2kNe9/EC9lOpHrbtTiQk/pO0ou+SPX94= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=YzgK5Lj3; arc=none smtp.client-ip=209.85.215.202 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=flex--seanjc.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="YzgK5Lj3" Received: by mail-pg1-f202.google.com with SMTP id 41be03b00d2f7-5e4df21f22dso1995368a12.0 for ; Fri, 16 Aug 2024 17:32:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1723854757; x=1724459557; darn=vger.kernel.org; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:from:to:cc:subject:date:message-id:reply-to; bh=SRMAqDHIaXd/9Vu41g3g8ugdHm3NdNHSXvqjD6sYwTs=; b=YzgK5Lj3n4Qo5wueRyqFl24cT8zBvP6zMinbfpL1pkAudT1RLnwxC43PX4m5tZRH8H EManmqNTki40C/Ifgnfk3xEr2pxK7yS6lREbaC73uADhbaUg57HkOhfXnREEPx6COUyw B6bZeVwnMARmQ9SEeSW0OIfhCTo6fTON8K9aV3ZtDJwiGCPeKKI0I8ogSNc1GuhBGvqf Jda3JhI0cgWRoEXSpyZmYYA0x1vv2iZpkqVP3D/ygQTAWweIGvLFUyJDASBEAd3eUESq OBAS7xIE4s43imiV4KCYMlD8vLiusBFwzFz8ZF/4abR+bEup+soMug7yk8tLerWGgPJt mwDA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1723854757; x=1724459557; h=cc:to:from:subject:message-id:references:mime-version:in-reply-to :date:x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=SRMAqDHIaXd/9Vu41g3g8ugdHm3NdNHSXvqjD6sYwTs=; b=XAVP02F2IJTnQQVDEWDIvPVnnZf+ddTMMqY6lxgAadC1e3cxbbOqIvype0cQwVpoc0 G5eVklRF/eH19CB1weLba9PjDBDikO4vYJvPlkP7MGkhNjd04MX3bKzg/dbAAb4xnyxq u/Z+srrl/q7uzkgDfLoTb5AbfmGZIt7M25qN62CjDOAhRQEnhqcLhQwiA9enLTLf6P2L 7fYisvKxUl6JUakpugQCLyHO93nb8CUiWD/22NY3XPMlI8li8S15ABvypZGPoZ0I3ONx oTkhfT9PdmxgtczfJ0eEEY/2hH9oF1nRCNLhLO1enF1wN+14kXE8j1BTBCPH9Qgun2FE ut5w== X-Gm-Message-State: AOJu0Yy7F9c3GWFpGIxGDxsKESbOlDpfVlyih82yQet+X8QomZZeIASw UEVSXpvyf/dvhcw43fqdGg+Yakqi4JomaV3GtZnCnPW3zJTANYfd4f6Yt1YMEQ4RWmEVVF+0DEX KEg== X-Google-Smtp-Source: AGHT+IEAl6su0XNJBkrmjngptpk1ledQh6hcsaLtOcC/+cBaPEkAwh8LlQVSAwROz41684Cp0mMJPQorlF0= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a05:6a02:595:b0:7b6:c922:4827 with SMTP id 41be03b00d2f7-7c6b2d40ce3mr64866a12.1.1723854757042; Fri, 16 Aug 2024 17:32:37 -0700 (PDT) Date: Fri, 16 Aug 2024 17:32:35 -0700 In-Reply-To: <20240718193543.624039-3-ilstam@amazon.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240718193543.624039-1-ilstam@amazon.com> <20240718193543.624039-3-ilstam@amazon.com> Message-ID: Subject: Re: [PATCH v2 2/6] KVM: Add KVM_CREATE_COALESCED_MMIO_BUFFER ioctl From: Sean Christopherson To: Ilias Stamatis Cc: kvm@vger.kernel.org, pbonzini@redhat.com, pdurrant@amazon.co.uk, dwmw@amazon.co.uk, nh-open-source@amazon.com, Paul Durrant Content-Type: text/plain; charset="us-ascii" On Thu, Jul 18, 2024, Ilias Stamatis wrote: > @@ -40,17 +42,14 @@ static int coalesced_mmio_in_range(struct kvm_coalesced_mmio_dev *dev, > return 1; > } > > -static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_dev *dev, u32 last) > +static int coalesced_mmio_has_room(struct kvm_coalesced_mmio_ring *ring, u32 last) > { > - struct kvm_coalesced_mmio_ring *ring; > - > /* Are we able to batch it ? */ > > /* last is the first free entry > * check if we don't meet the first used entry > * there is always one unused entry in the buffer > */ > - ring = dev->kvm->coalesced_mmio_ring; > if ((last + 1) % KVM_COALESCED_MMIO_MAX == READ_ONCE(ring->first)) { > /* full */ > return 0; > @@ -65,17 +64,28 @@ static int coalesced_mmio_write(struct kvm_vcpu *vcpu, > { > struct kvm_coalesced_mmio_dev *dev = to_mmio(this); > struct kvm_coalesced_mmio_ring *ring = dev->kvm->coalesced_mmio_ring; > + spinlock_t *lock = dev->buffer_dev ? > + &dev->buffer_dev->ring_lock : > + &dev->kvm->ring_lock; I'd prefer spinlock_t *lock = dev->buffer_dev ? &dev->buffer_dev->ring_lock : &dev->kvm->ring_lock; to make it more obvious which parts the "guts" of the effective if-statement. > diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c > index d0788d0a72cc..9eb22287384f 100644 > --- a/virt/kvm/kvm_main.c > +++ b/virt/kvm/kvm_main.c > @@ -5246,6 +5246,10 @@ static long kvm_vm_ioctl(struct file *filp, > r = kvm_vm_ioctl_unregister_coalesced_mmio(kvm, &zone); > break; > } > + case KVM_CREATE_COALESCED_MMIO_BUFFER: { Curly braces aren't needed, the above case has 'em because it declares local variables. > + r = kvm_vm_ioctl_create_coalesced_mmio_buffer(kvm); > + break; > + } > #endif > case KVM_IRQFD: { > struct kvm_irqfd data; > -- > 2.34.1 >