From nobody Sat Feb 7 15:26:35 2026 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 79651236A6A for ; Mon, 10 Mar 2025 17:23:33 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741627413; cv=none; b=bnTJOnk7okOCTKuyLBkFEnIvMqzldkK24SF8KyhUYQXwbmvt3CAV3b3zEfvwjwJRUCP670lb6W9ozoF4axP6D+P/deglPO5CpWTHkO0ffzV6zLc1fShAemY/Z8heStdZGLzaaKmBj0rpE9jeveVArSyOHmVIiC8xkF+DqHKYL88= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1741627413; c=relaxed/simple; bh=XwNyPWkuo3x8UEQgYUucQN44sSUMxDXOQT6wzHvLom0=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=d84ItyLXBmMQegyKWh/BYGIS4C0o2pxRodsiGEspcTmmnxMl1gld4wUuW4E1dfyH5mF2HFYi5ZMH5F9+13ZwcRav6ieWNxZ+T1uDR963X0VET/0+qB+02+fwC9jTFASA2Jd3izgUJpAiAFlNzH1T2fcgfNskFLw/sLx7ivKuuJY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=krWQwApA; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="krWQwApA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id BC673C4CEEC; Mon, 10 Mar 2025 17:23:32 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1741627412; bh=XwNyPWkuo3x8UEQgYUucQN44sSUMxDXOQT6wzHvLom0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=krWQwApAFooJw8RDR+VQklpBSPp/jb0qvzqLu5pCDpb7eW76XF5JyZwxHg4cy4FEU XvMGRSStteW7kyuxgIk/BsxYaqWeRdLQaa6PTij9bEWwE2+rClOI+uMaCmLkdK2M8K 8MzU+FiOthWHwlK/bdFrs0qShtkdkmaAE2UaZYZM8XMrmJtSnawjt/mLWf6uLnDD0d C+kVoxCRMP9beh4TlBf27mnPlUXccx8TLOwatzKscv0CoCZgrpLWWu7zmxnnpVRCyE Liha99fJhrQLYsMoDyQNiPeJZ4C//wNOTCnt8/6+cNVwvl2dr6Jp1ifIZUVfh+ZNIy g/6Q0LWdHYpWA== From: SeongJae Park To: Andrew Morton Cc: SeongJae Park , "Liam R. Howlett" , David Hildenbrand , Lorenzo Stoakes , Shakeel Butt , Vlastimil Babka , kernel-team@meta.com, linux-kernel@vger.kernel.org, linux-mm@kvack.org Subject: [PATCH 8/9] mm/madvise: batch tlb flushes for [process_]madvise(MADV_{DONTNEED[_LOCKED],FREE}) Date: Mon, 10 Mar 2025 10:23:17 -0700 Message-Id: <20250310172318.653630-9-sj@kernel.org> X-Mailer: git-send-email 2.39.5 In-Reply-To: <20250310172318.653630-1-sj@kernel.org> References: <20250310172318.653630-1-sj@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" MADV_DONTNEED[_LOCKED] and MADV_FREE internal logics for [process_]madvise() can be invoked with batched tlb flushes. Update vector_madvise() and do_madvise(), which are called for the two system calls respectively, to use those in the efficient way. Initialize an mmu_gather object before starting the internal works, and flush the gathered tlb entries at once after all the internal works are done. Signed-off-by: SeongJae Park --- mm/madvise.c | 51 +++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 47 insertions(+), 4 deletions(-) diff --git a/mm/madvise.c b/mm/madvise.c index d7ea71c6422c..d5f4ce3041a4 100644 --- a/mm/madvise.c +++ b/mm/madvise.c @@ -905,6 +905,7 @@ static bool madvise_dontneed_free_valid_vma(struct vm_a= rea_struct *vma, =20 struct madvise_behavior { int behavior; + struct mmu_gather *tlb; }; =20 static long madvise_dontneed_free(struct vm_area_struct *vma, @@ -964,9 +965,11 @@ static long madvise_dontneed_free(struct vm_area_struc= t *vma, } =20 if (behavior =3D=3D MADV_DONTNEED || behavior =3D=3D MADV_DONTNEED_LOCKED) - return madvise_dontneed_single_vma(NULL, vma, start, end); + return madvise_dontneed_single_vma( + madv_behavior->tlb, vma, start, end); else if (behavior =3D=3D MADV_FREE) - return madvise_free_single_vma(NULL, vma, start, end); + return madvise_free_single_vma( + madv_behavior->tlb, vma, start, end); else return -EINVAL; } @@ -1639,6 +1642,32 @@ static void madvise_unlock(struct mm_struct *mm, int= behavior) mmap_read_unlock(mm); } =20 +static bool madvise_batch_tlb_flush(int behavior) +{ + switch (behavior) { + case MADV_DONTNEED: + case MADV_DONTNEED_LOCKED: + return true; + default: + return false; + } +} + +static void madvise_init_tlb(struct madvise_behavior *madv_behavior, + struct mm_struct *mm) +{ + if (!madvise_batch_tlb_flush(madv_behavior->behavior)) + return; + tlb_gather_mmu(madv_behavior->tlb, mm); +} + +static void madvise_finish_tlb(struct madvise_behavior *madv_behavior) +{ + if (!madvise_batch_tlb_flush(madv_behavior->behavior)) + return; + tlb_finish_mmu(madv_behavior->tlb); +} + static bool is_valid_madvise(unsigned long start, size_t len_in, int behav= ior) { size_t len; @@ -1791,14 +1820,20 @@ static int madvise_do_behavior(struct mm_struct *mm, int do_madvise(struct mm_struct *mm, unsigned long start, size_t len_in, i= nt behavior) { int error; - struct madvise_behavior madv_behavior =3D {.behavior =3D behavior}; + struct mmu_gather tlb; + struct madvise_behavior madv_behavior =3D { + .behavior =3D behavior, + .tlb =3D &tlb, + }; =20 if (madvise_should_skip(start, len_in, behavior, &error)) return error; error =3D madvise_lock(mm, behavior); if (error) return error; + madvise_init_tlb(&madv_behavior, mm); error =3D madvise_do_behavior(mm, start, len_in, &madv_behavior); + madvise_finish_tlb(&madv_behavior); madvise_unlock(mm, behavior); =20 return error; @@ -1815,13 +1850,18 @@ static ssize_t vector_madvise(struct mm_struct *mm,= struct iov_iter *iter, { ssize_t ret =3D 0; size_t total_len; - struct madvise_behavior madv_behavior =3D {.behavior =3D behavior}; + struct mmu_gather tlb; + struct madvise_behavior madv_behavior =3D { + .behavior =3D behavior, + .tlb =3D &tlb, + }; =20 total_len =3D iov_iter_count(iter); =20 ret =3D madvise_lock(mm, behavior); if (ret) return ret; + madvise_init_tlb(&madv_behavior, mm); =20 while (iov_iter_count(iter)) { unsigned long start =3D (unsigned long)iter_iov_addr(iter); @@ -1850,14 +1890,17 @@ static ssize_t vector_madvise(struct mm_struct *mm,= struct iov_iter *iter, } =20 /* Drop and reacquire lock to unwind race. */ + madvise_finish_tlb(&madv_behavior); madvise_unlock(mm, behavior); madvise_lock(mm, behavior); + madvise_init_tlb(&madv_behavior, mm); continue; } if (ret < 0) break; iov_iter_advance(iter, iter_iov_len(iter)); } + madvise_finish_tlb(&madv_behavior); madvise_unlock(mm, behavior); =20 ret =3D (total_len - iov_iter_count(iter)) ? : ret; --=20 2.39.5