Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1761054AbYGOMQS (ORCPT ); Tue, 15 Jul 2008 08:16:18 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1757217AbYGOMMu (ORCPT ); Tue, 15 Jul 2008 08:12:50 -0400 Received: from il.qumranet.com ([212.179.150.194]:30360 "EHLO il.qumranet.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755979AbYGOMMm (ORCPT ); Tue, 15 Jul 2008 08:12:42 -0400 From: Avi Kivity To: kvm@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Marcelo Tosatti Subject: [PATCH 10/19] KVM: mmu_shrink: kvm_mmu_zap_page requires slots_lock to be held Date: Tue, 15 Jul 2008 15:12:29 +0300 Message-Id: <1216123958-10717-11-git-send-email-avi@qumranet.com> X-Mailer: git-send-email 1.5.6.1 In-Reply-To: <1216123958-10717-1-git-send-email-avi@qumranet.com> References: <1216123958-10717-1-git-send-email-avi@qumranet.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1286 Lines: 44 From: Marcelo Tosatti kvm_mmu_zap_page() needs slots lock held (rmap_remove->gfn_to_memslot, for example). Since kvm_lock spinlock is held in mmu_shrink(), do a non-blocking down_read_trylock(). Untested. Signed-off-by: Avi Kivity --- arch/x86/kvm/mmu.c | 3 +++ 1 files changed, 3 insertions(+), 0 deletions(-) diff --git a/arch/x86/kvm/mmu.c b/arch/x86/kvm/mmu.c index 1fd8e3b..ff7cf63 100644 --- a/arch/x86/kvm/mmu.c +++ b/arch/x86/kvm/mmu.c @@ -1987,6 +1987,8 @@ static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask) list_for_each_entry(kvm, &vm_list, vm_list) { int npages; + if (!down_read_trylock(&kvm->slots_lock)) + continue; spin_lock(&kvm->mmu_lock); npages = kvm->arch.n_alloc_mmu_pages - kvm->arch.n_free_mmu_pages; @@ -1999,6 +2001,7 @@ static int mmu_shrink(int nr_to_scan, gfp_t gfp_mask) nr_to_scan--; spin_unlock(&kvm->mmu_lock); + up_read(&kvm->slots_lock); } if (kvm_freed) list_move_tail(&kvm_freed->vm_list, &vm_list); -- 1.5.6.1 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/