From nobody Wed Dec 17 15:38:04 2025 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 79BD72417C9; Mon, 17 Mar 2025 14:21:49 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742221311; cv=none; b=YpJ8QS+hYv+B2IGo3cn3Ou/gMhiSnB1c2qEkzQndSeUTOVSZIK67Mhph3Ln22JfjYUHyZpfNe23VaCVNFFvIQdBKHmPJFwD4nrdPJIVvMYCIeA2wtqxAGz5InoGivVFA/4qoea5rYgkY9ZFyuXQQ2AsTnexKGtx3SPB59an4OG0= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1742221311; c=relaxed/simple; bh=sJY3k14WBl1j2uqNZ+rNzVrFO/O8YxCuCcrCnNtLeO4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=NqFeSOGav7yi8PgJgDv8gLDFrAAzURhWCNg96wSmmxvRQs4DWxq9mkOLr9/NRI0sv+OH3gmYwOMEN7uh3v/o4tgN5lY8ocehjKElObNVqFUJwrxa5vlaV2w1x9sF0uSTHNFlqYdigObfDA+PjzYf8bMQcX8Ic923SXhpMyy1sdY= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 005532576; Mon, 17 Mar 2025 07:21:58 -0700 (PDT) Received: from e123572-lin.arm.com (e123572-lin.cambridge.arm.com [10.1.194.54]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id CC9AA3F63F; Mon, 17 Mar 2025 07:21:44 -0700 (PDT) From: Kevin Brodsky To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Kevin Brodsky , Albert Ou , Andreas Larsson , Andrew Morton , Catalin Marinas , Dave Hansen , "David S. Miller" , Geert Uytterhoeven , Linus Walleij , Madhavan Srinivasan , Mark Rutland , Matthew Wilcox , Michael Ellerman , "Mike Rapoport (IBM)" , Palmer Dabbelt , Paul Walmsley , Peter Zijlstra , Qi Zheng , Ryan Roberts , Will Deacon , Yang Shi , linux-arch@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-csky@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-openrisc@vger.kernel.org, linux-riscv@lists.infradead.org, linux-s390@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org Subject: [PATCH 04/11] powerpc: mm: Call ctor/dtor for kernel PTEs Date: Mon, 17 Mar 2025 14:16:53 +0000 Message-ID: <20250317141700.3701581-5-kevin.brodsky@arm.com> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20250317141700.3701581-1-kevin.brodsky@arm.com> References: <20250317141700.3701581-1-kevin.brodsky@arm.com> 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" The generic implementation of pte_{alloc_one,free}_kernel now calls the [cd]tor, without initialising the ptlock needlessly as pagetable_pte_ctor() skips it for init_mm. On powerpc, all functions related to PTE allocation are implemented by common helpers, which are passed a boolean to differentiate user from kernel pgtables. This patch aligns the powerpc implementation with the generic one by calling pagetable_pte_[cd]tor() unconditionally in those helpers. Signed-off-by: Kevin Brodsky --- arch/powerpc/mm/pgtable-frag.c | 30 +++++++++++++----------------- 1 file changed, 13 insertions(+), 17 deletions(-) diff --git a/arch/powerpc/mm/pgtable-frag.c b/arch/powerpc/mm/pgtable-frag.c index 387e9b1fe12c..77e55eac16e4 100644 --- a/arch/powerpc/mm/pgtable-frag.c +++ b/arch/powerpc/mm/pgtable-frag.c @@ -56,19 +56,17 @@ static pte_t *__alloc_for_ptecache(struct mm_struct *mm= , int kernel) { void *ret =3D NULL; struct ptdesc *ptdesc; + gfp_t gfp =3D PGALLOC_GFP; =20 - if (!kernel) { - ptdesc =3D pagetable_alloc(PGALLOC_GFP | __GFP_ACCOUNT, 0); - if (!ptdesc) - return NULL; - if (!pagetable_pte_ctor(mm, ptdesc)) { - pagetable_free(ptdesc); - return NULL; - } - } else { - ptdesc =3D pagetable_alloc(PGALLOC_GFP, 0); - if (!ptdesc) - return NULL; + if (!kernel) + gfp |=3D __GFP_ACCOUNT; + + ptdesc =3D pagetable_alloc(gfp, 0); + if (!ptdesc) + return NULL; + if (!pagetable_pte_ctor(mm, ptdesc)) { + pagetable_free(ptdesc); + return NULL; } =20 atomic_set(&ptdesc->pt_frag_refcount, 1); @@ -124,12 +122,10 @@ void pte_fragment_free(unsigned long *table, int kern= el) =20 BUG_ON(atomic_read(&ptdesc->pt_frag_refcount) <=3D 0); if (atomic_dec_and_test(&ptdesc->pt_frag_refcount)) { - if (kernel) - pagetable_free(ptdesc); - else if (folio_test_clear_active(ptdesc_folio(ptdesc))) - call_rcu(&ptdesc->pt_rcu_head, pte_free_now); - else + if (kernel || !folio_test_clear_active(ptdesc_folio(ptdesc))) pte_free_now(&ptdesc->pt_rcu_head); + else + call_rcu(&ptdesc->pt_rcu_head, pte_free_now); } } =20 --=20 2.47.0