From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from mail-pl1-f201.google.com (mail-pl1-f201.google.com [209.85.214.201]) (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 3621138FA0 for ; Tue, 11 Jun 2024 16:35:36 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=209.85.214.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718123737; cv=none; b=dXoOgF9VqEMTRzXZUWyI9DQ527awjOARPevihVXqzWCTsnYLZj76nrSIHvxtvOSv+ZYncJTPBYSqRwr34Qv4zb+yym+ORhaXC+Ql/OtwIUBESmTTx7AcgutJnee3GvYoROkHfiKt6KIuEK1OrS1IlQgEkGarWoimmTFOoIK5gVY= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1718123737; c=relaxed/simple; bh=3HM6i6zrhqS92eFX0rcBTaE34IL7ONn3eX6LnpwKS8Q=; h=Date:In-Reply-To:Mime-Version:References:Message-ID:Subject:From: To:Cc:Content-Type; b=gyowaCk98/laS+QKZt3XC3XjBFnwRJTL/vFD1O07Q5ISP1oBuwiE/Fs53b9GQxO2GpicxvkpZi685WY+vC6O+5kZi8/6x8ArV3Fg9jR8FgfKt4kNzAxnVNsSAlP+rLZOFCCl80Zx6594u6fdsKBMLoX9vez+3wpPNlFm3+aBa6I= 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=HPav3AZk; arc=none smtp.client-ip=209.85.214.201 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="HPav3AZk" Received: by mail-pl1-f201.google.com with SMTP id d9443c01a7336-1f656692564so10886425ad.2 for ; Tue, 11 Jun 2024 09:35:36 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20230601; t=1718123735; x=1718728535; 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=sy8cYUcbFFJWNmfBV4hjqU10SqwSRoXFxmzf2bgnVG8=; b=HPav3AZkAkfqsescJX/g6FEn6DO6q/l8p4OOm9U0LrmGve7dAxbbtol2Do+VZPg3KY FzI/kuY52lbpUQ8U/xIPwrexWNibNIHtLC0hBL2qtKJyxGaxWNeW8z0gkMNuGhCw/n3w CEfh29CCxif7FFj2eXwhj4HUWr4m2x4EwOG7XrmMwlMAwV7bkwKeaw/VAqbGZLDI69+u ijnGslh70VDUptr5AKMHVLfcwKsgYJz5QRXzZvjCVccB/sgcHlqS49Sfvz/sKCHhjSd1 HpsoqytjcVtOtr02zXAqsWwQOxyq41wD1ox1Z3zBEXyQzCn0LoPgjfhzj4k7YdlZaoDg 8RWw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1718123735; x=1718728535; 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=sy8cYUcbFFJWNmfBV4hjqU10SqwSRoXFxmzf2bgnVG8=; b=tYeN904A0cHX9o7i05S4BHpZcGTs8PT8OhFzq5eLDIw/q5Z5v6XbruI4Ybr1qUbMAb I5lc6+qAXrkCM03aMsm0gCy6GASh2yy85Ot9VZJqJdqP3QPEPJtRb5XeI5nhj5QkxO4R Vsxc+ZGODL+IoqgZFFgGzQRqHowRIalSjBtQTYr9Vz0CkMy/ab+FGMavtB2R97PM862D YPgiNZNXFYuWDn21uJCbB2Ma2ECLjQmd+QaMpjFYZTGzLnU1GwdeJdTRaP+//86XB26d z9l7Ns6nkeL6MOAcg1jy6j6+1T+LscLuP9bZDtZV5Swxkn9aeh4NNUev12QhjL7yt56N up4g== X-Forwarded-Encrypted: i=1; AJvYcCV39VYqulyhLt/NckPAyCCLOUxgz00Ngv9tIxWP1XgLl7Sqsv96wjVyuaj494HJWwDGdaT9kIo7swaVkcTbvzSbvYYW X-Gm-Message-State: AOJu0Yzsd82yTTLWURXgPzwr53os7dQ4AfUuEI3aPT68zcj/qZgNHvTu ighuiXx3t++izyYHY1LAG5ZrzJ/KIxLYPlXlVNsV+E9i5FEINy1R+JeVRqzpSTz7s6TXEg4ifAi boQ== X-Google-Smtp-Source: AGHT+IFqXchqKKKSOXvmsXF4dzM7UtKtVZ8RsUC4UyrsKBXtHV0YGZj0BXlb8PWK7cGM8Xh3b9rpS7Epjko= X-Received: from zagreus.c.googlers.com ([fda3:e722:ac3:cc00:7f:e700:c0a8:5c37]) (user=seanjc job=sendgmr) by 2002:a17:902:ea03:b0:1f3:f8c:55d5 with SMTP id d9443c01a7336-1f6d02be357mr2172085ad.2.1718123735342; Tue, 11 Jun 2024 09:35:35 -0700 (PDT) Date: Tue, 11 Jun 2024 09:35:32 -0700 In-Reply-To: Precedence: bulk X-Mailing-List: kvm@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: Mime-Version: 1.0 References: <20240509181133.837001-1-dmatlack@google.com> Message-ID: Subject: Re: [PATCH v3] KVM: x86/mmu: Always drop mmu_lock to allocate TDP MMU SPs for eager splitting From: Sean Christopherson To: David Matlack Cc: Paolo Bonzini , kvm@vger.kernel.org, Bibo Mao Content-Type: text/plain; charset="us-ascii" On Tue, Jun 11, 2024, David Matlack wrote: > On 2024-06-03 11:13 AM, Sean Christopherson wrote: > > On Thu, May 09, 2024, David Matlack wrote: > > > diff --git a/arch/x86/kvm/mmu/tdp_mmu.c b/arch/x86/kvm/mmu/tdp_mmu.c > > > index aaa2369a9479..2089d696e3c6 100644 > > > --- a/arch/x86/kvm/mmu/tdp_mmu.c > > > +++ b/arch/x86/kvm/mmu/tdp_mmu.c > > > @@ -1385,11 +1385,11 @@ bool kvm_tdp_mmu_wrprot_slot(struct kvm *kvm, > > > return spte_set; > > > } > > > > > > -static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(gfp_t gfp) > > > +static struct kvm_mmu_page *__tdp_mmu_alloc_sp_for_split(void) > > > { > > > + gfp_t gfp = GFP_KERNEL_ACCOUNT | __GFP_ZERO; > > > struct kvm_mmu_page *sp; > > > > > > - gfp |= __GFP_ZERO; > > > > > > sp = kmem_cache_alloc(mmu_page_header_cache, gfp); > > > > This can more simply and cleary be: > > > > sp = kmem_cache_zalloc(mmu_page_header_cache, GFP_KERNEL_ACCOUNT); > > Will do. And I assume you'd prefer get_zeroed_page(GFP_KERNEL_ACCOUNT) > as well below? Ah, yeah, good catch!