From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-ed1-f74.google.com (mail-ed1-f74.google.com [209.85.208.74]) (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 610573AE719 for ; Fri, 6 Mar 2026 14:02:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.208.74 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772805770; cv=none; b=C7T5xhKhrtJYG0sRk8qNHIB4Q2ygJSFru4ol+Jrd807YVMZdwoprX9jxC+oGpK0A9qDn/oJsIW2aDDheHf7daxIEjlAYgOorLjwp+ks8gl5fhXogZJoU3Fgo59CNxJS8XoXJNduBrjTvcMWtQE4wo5OQJYEQwuUV3qUBf5ub+nc= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1772805770; c=relaxed/simple; bh=dssjA3u+VFXpsFKHFhYOAlR5Hr1cip10VgtJuYqdW38=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=ZhTEAvf0WjusAjZCh6P67h7pHz90hNskWtBcg/wQvTj+4T6ZXsoQnDFNeUDejp2iU8HWY+ZY4QOe4ZGappAhk+j7FRXgul6TtmyGqZlTIqkhNXbNOSVfovkFw+GkqUSw/CgFBehj6OsY6T3oipZPUuND7vki4gRM2bobj1GJPh4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=reject dis=none) header.from=google.com; spf=pass smtp.mailfrom=flex--tabba.bounces.google.com; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b=llTxi5K0; arc=none smtp.client-ip=209.85.208.74 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--tabba.bounces.google.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=google.com header.i=@google.com header.b="llTxi5K0" Received: by mail-ed1-f74.google.com with SMTP id 4fb4d7f45d1cf-6614741a740so2353555a12.0 for ; Fri, 06 Mar 2026 06:02:49 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1772805768; x=1773410568; 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=nrle6LcPHnpw57JFxD6jZW7nwqfyHVVEsUa7FBi+veg=; b=llTxi5K0TVYEySHGstMrHyVkLT43VQahQiAc3A1+e/11EhsU3HNs4Hp1n/QwrCootr 84DVUDsFZLUMQv1a9vWJLmy3boQVIKUOdRR/XDPdJ/nRLYZPzjbD1Sm0lDF0Cxi+vNyk kXbZJIiM6s9HCtEnUjW9p7eHcLVPZHqFl5fGP7rNx4WGw4v8VdoEhgNpnPtxMHkVPKcd ewPpS+rPhCLz6wqZNbfSmf+5ebJGmaEsMfIkHgUCWwKLq5iA0db0cmcQnnwEKuhuAhDl N5C4tlqvvnCQQ6U7T68BamNLW6ez6DGDgYGRxvF1iHPIXwc66F5YchikiDRIvnfb1O31 Ulkw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1772805768; x=1773410568; 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=nrle6LcPHnpw57JFxD6jZW7nwqfyHVVEsUa7FBi+veg=; b=p+DJsntCirk5AqFvx3nKIj/RRKqel0/N51Hmd0xed2Vf+/tpzCljpG8YM82GvCPO22 AoXhzCvfMbo1ySgSt6ZKSn3VnqMNddzqiEnX+vmmhIKazHILd1oz/c1HqYu/ri+opxvv MzSC27FTdcPQoXciOmV7DlLhRg+ZA3o3Z8++ni3ejQXLKFrSXTgwXRaplZqTpXZLD5YS OgGmRHHzytKrYFC1d7OQFpD0AXRCIgiFO4cYOK/lf9QbhSQA6nOrUY6eHYPnj8Wi3ltw mJ9JNAr/MQfZb4XHCFMsOSRz9AbAonj8uKKbRM7ED6hWqfElEvX+lrDTRkqT8UEMI8wz u2NA== X-Gm-Message-State: AOJu0YyEjMrt0PZEa2YHl8yLJMwCB8A5xl6aBOrdmnDMS2YvkVtY8CIW ZmQaKHwFrNH7jfoBdO3ZpkehN7braf95F5cqiD/YO8zTpM/4/M9XPz2X2/JoZtg4GVikeZEku8p 7M1gbAcyIecJSM77G2iOmPxkuVOdXpdLTSRDkxZLrUnZ2JQ6jEuzz1+opRVZfKIer6KKi8t90TO emtRSpF/INJb+r0xpPfDkJhhxPUus= X-Received: from edn26-n2.prod.google.com ([2002:a05:6402:a0da:20b0:661:18d5:ee37]) (user=tabba job=prod-delivery.src-stubby-dispatcher) by 2002:a05:6402:1d48:b0:65f:9c21:e68e with SMTP id 4fb4d7f45d1cf-6619d45a9f3mr1338158a12.5.1772805767541; Fri, 06 Mar 2026 06:02:47 -0800 (PST) Date: Fri, 6 Mar 2026 14:02:30 +0000 In-Reply-To: <20260306140232.2193802-1-tabba@google.com> Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20260306140232.2193802-1-tabba@google.com> X-Mailer: git-send-email 2.53.0.473.g4a7958ca14-goog Message-ID: <20260306140232.2193802-12-tabba@google.com> Subject: [PATCH v1 11/13] KVM: arm64: Optimize early exit checks in kvm_s2_fault_pin_pfn() From: Fuad Tabba To: kvm@vger.kernel.org, kvmarm@lists.linux.dev, linux-arm-kernel@lists.infradead.org Cc: maz@kernel.org, oliver.upton@linux.dev, joey.gouly@arm.com, suzuki.poulose@arm.com, yuzenghui@huawei.com, catalin.marinas@arm.com, will@kernel.org, qperret@google.com, vdonnefort@google.com, tabba@google.com Content-Type: text/plain; charset="UTF-8" Optimize the early exit checks in kvm_s2_fault_pin_pfn by grouping all error responses under the generic is_error_noslot_pfn check first, avoiding unnecessary branches in the hot path. Signed-off-by: Fuad Tabba --- arch/arm64/kvm/mmu.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/arch/arm64/kvm/mmu.c b/arch/arm64/kvm/mmu.c index 2d6e749c1756..9265a7fc43f7 100644 --- a/arch/arm64/kvm/mmu.c +++ b/arch/arm64/kvm/mmu.c @@ -1791,12 +1791,13 @@ static int kvm_s2_fault_pin_pfn(struct kvm_s2_fault *fault) fault->pfn = __kvm_faultin_pfn(fault->memslot, fault->gfn, fault->write_fault ? FOLL_WRITE : 0, &fault->writable, &fault->page); - if (fault->pfn == KVM_PFN_ERR_HWPOISON) { - kvm_send_hwpoison_signal(fault->hva, __ffs(fault->vma_pagesize)); - return 0; - } - if (is_error_noslot_pfn(fault->pfn)) + if (unlikely(is_error_noslot_pfn(fault->pfn))) { + if (fault->pfn == KVM_PFN_ERR_HWPOISON) { + kvm_send_hwpoison_signal(fault->hva, __ffs(fault->vma_pagesize)); + return 0; + } return -EFAULT; + } return 1; } -- 2.53.0.473.g4a7958ca14-goog