From nobody Sun Feb 8 02:41:46 2026 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id DF84D34BA4B; Mon, 6 Oct 2025 04:26:40 +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=1759724803; cv=none; b=mqV5wGRkoI3K9sG6dzkbCCTdI9sTlyzfxzzjifQePW59VsjAmpkg6WGn3CIaWpp8FPsGiMJqTplf+D0RHu2zR8eumDVjAt6KNNRlVquJw9pdDJOxcuWApzKf0KFsBnaZKo70ya4BrYP7AkRu9bjToQDcGh/k2FbUkchBt9X+jXM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1759724803; c=relaxed/simple; bh=2nzYjvGIFu8psbcqnk+YGYnoYohJvp6urVvOGRvpTAU=; h=From:To:Cc:Subject:Date:Message-Id:MIME-Version; b=Fru4qJqdyeslqegNYZbTIQ+9EX5ppAF9sT305XbvjnYyFXYePpK/D2sQRRmOPxIihOwuBuB642XacYcto+UMR0BXRFjZPMcdTSJnghcuHMc9SgsoGhqFxgbqScKfjsMQ+GlR6XDHlch2C5PQc04winCLMl+1AeECDr76Qcs5HQU= 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 37B8C1516; Sun, 5 Oct 2025 21:26:26 -0700 (PDT) Received: from ergosum.cambridge.arm.com (ergosum.cambridge.arm.com [10.1.196.45]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id D44AA3F59E; Sun, 5 Oct 2025 21:26:32 -0700 (PDT) From: Anshuman Khandual To: linux-perf-users@vger.kernel.org Cc: Anshuman Khandual , Peter Zijlstra , Ingo Molnar , Arnaldo Carvalho de Melo , Namhyung Kim , linux-kernel@vger.kernel.org Subject: [PATCH] perf/events: replace READ_ONCE() with standard page table accessors Date: Mon, 6 Oct 2025 05:26:22 +0100 Message-Id: <20251006042622.1743675-1-anshuman.khandual@arm.com> X-Mailer: git-send-email 2.30.2 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" Replace READ_ONCE() with standard page table accessors i.e pxdp_get() which anyways default into READ_ONCE() in cases where platform does not override. Cc: Peter Zijlstra Cc: Ingo Molnar Cc: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: linux-perf-users@vger.kernel.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual --- kernel/events/core.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/kernel/events/core.c b/kernel/events/core.c index 820127536e62..952ba4e3d881 100644 --- a/kernel/events/core.c +++ b/kernel/events/core.c @@ -8110,7 +8110,7 @@ static u64 perf_get_pgtable_size(struct mm_struct *mm= , unsigned long addr) pte_t *ptep, pte; =20 pgdp =3D pgd_offset(mm, addr); - pgd =3D READ_ONCE(*pgdp); + pgd =3D pgdp_get(pgdp); if (pgd_none(pgd)) return 0; =20 @@ -8118,7 +8118,7 @@ static u64 perf_get_pgtable_size(struct mm_struct *mm= , unsigned long addr) return pgd_leaf_size(pgd); =20 p4dp =3D p4d_offset_lockless(pgdp, pgd, addr); - p4d =3D READ_ONCE(*p4dp); + p4d =3D p4dp_get(p4dp); if (!p4d_present(p4d)) return 0; =20 @@ -8126,7 +8126,7 @@ static u64 perf_get_pgtable_size(struct mm_struct *mm= , unsigned long addr) return p4d_leaf_size(p4d); =20 pudp =3D pud_offset_lockless(p4dp, p4d, addr); - pud =3D READ_ONCE(*pudp); + pud =3D pudp_get(pudp); if (!pud_present(pud)) return 0; =20 --=20 2.30.2