From patchwork Mon Jan 23 17:37:31 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Stefan Roesch X-Patchwork-Id: 13112700 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 vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id DB7ECC05027 for ; Mon, 23 Jan 2023 18:03:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233476AbjAWSD1 (ORCPT ); Mon, 23 Jan 2023 13:03:27 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:42530 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S233451AbjAWSDW (ORCPT ); Mon, 23 Jan 2023 13:03:22 -0500 Received: from 66-220-144-178.mail-mxout.facebook.com (66-220-144-178.mail-mxout.facebook.com [66.220.144.178]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 50C1B305CC for ; Mon, 23 Jan 2023 10:03:19 -0800 (PST) Received: by dev0134.prn3.facebook.com (Postfix, from userid 425415) id 4A5615616BD7; Mon, 23 Jan 2023 09:37:56 -0800 (PST) From: Stefan Roesch To: linux-mm@kvack.org Cc: shr@devkernel.io, linux-doc@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-trace-kernel@vger.kernel.org Subject: [RESEND RFC PATCH v1 03/20] mm: add flag to __ksm_exit call Date: Mon, 23 Jan 2023 09:37:31 -0800 Message-Id: <20230123173748.1734238-4-shr@devkernel.io> X-Mailer: git-send-email 2.30.2 In-Reply-To: <20230123173748.1734238-1-shr@devkernel.io> References: <20230123173748.1734238-1-shr@devkernel.io> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This adds the flag parameter to the __ksm_exit() call. This allows to distinguish if this call is for an prctl or madvise invocation. Signed-off-by: Stefan Roesch --- include/linux/ksm.h | 8 +++++--- mm/ksm.c | 8 ++++++-- 2 files changed, 11 insertions(+), 5 deletions(-) diff --git a/include/linux/ksm.h b/include/linux/ksm.h index 50e6b56092f3..d38a05a36298 100644 --- a/include/linux/ksm.h +++ b/include/linux/ksm.h @@ -18,8 +18,8 @@ #ifdef CONFIG_KSM int ksm_madvise(struct vm_area_struct *vma, unsigned long start, unsigned long end, int advice, unsigned long *vm_flags); -void __ksm_exit(struct mm_struct *mm); int __ksm_enter(struct mm_struct *mm, int flag); +void __ksm_exit(struct mm_struct *mm, int flag); static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) { @@ -32,8 +32,10 @@ static inline int ksm_fork(struct mm_struct *mm, struct mm_struct *oldmm) static inline void ksm_exit(struct mm_struct *mm) { - if (test_bit(MMF_VM_MERGEABLE, &mm->flags)) - __ksm_exit(mm); + if (test_bit(MMF_VM_MERGE_ANY, &mm->flags)) + __ksm_exit(mm, MMF_VM_MERGE_ANY); + else if (test_bit(MMF_VM_MERGEABLE, &mm->flags)) + __ksm_exit(mm, MMF_VM_MERGEABLE); } /* diff --git a/mm/ksm.c b/mm/ksm.c index d84a244fe224..83796328574c 100644 --- a/mm/ksm.c +++ b/mm/ksm.c @@ -2563,12 +2563,16 @@ int __ksm_enter(struct mm_struct *mm, int flag) return 0; } -void __ksm_exit(struct mm_struct *mm) +void __ksm_exit(struct mm_struct *mm, int flag) { struct ksm_mm_slot *mm_slot; struct mm_slot *slot; int easy_to_free = 0; + if (!(current->flags & PF_EXITING) && flag == MMF_VM_MERGE_ANY && + test_bit(MMF_VM_MERGE_ANY, &mm->flags)) + clear_bit(MMF_VM_MERGE_ANY, &mm->flags); + /* * This process is exiting: if it's straightforward (as is the * case when ksmd was never running), free mm_slot immediately. @@ -2595,7 +2599,7 @@ void __ksm_exit(struct mm_struct *mm) if (easy_to_free) { mm_slot_free(mm_slot_cache, mm_slot); - clear_bit(MMF_VM_MERGEABLE, &mm->flags); + clear_bit(flag, &mm->flags); mmdrop(mm); } else if (mm_slot) { mmap_write_lock(mm);