From nobody Fri Apr 10 20:53:06 2026 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 23A48C4332F for ; Tue, 27 Dec 2022 03:09:22 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230007AbiL0DJU (ORCPT ); Mon, 26 Dec 2022 22:09:20 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38244 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229792AbiL0DIw (ORCPT ); Mon, 26 Dec 2022 22:08:52 -0500 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id EB71F10E9 for ; Mon, 26 Dec 2022 19:08:51 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1672110531; x=1703646531; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=2hNvtI+I64q9AU5Zc+yHHwHftID1PyaOfc87+zaI4fg=; b=NLusNa0tTl3d92B5cSckeus1ibwrLRBvcNbmvLFUM1faxNowaGQ5j/y7 XTNR8j5Yxz709mRkS1hAMzfZGGDA1igY4NXSxI7H/nI/xvLS3beDELgFz C/ziUYQLiErLuHT1Ke1s2lWOnzAST/mv2k+tbCTkp2CDbccgmT6xg+qyS /vqIB3z4j2F7CPbekT7cTSKTHQknfX1uvVVEg74jTTlBMBduckXwIbTo4 qMv+jrC3jyw+1CwvgIVD8fVYbW6V4hqt69ONZLV7n/JXSFsdYT/qFYAQ9 TFV+w3oxIRUnc5bRzpe4UXEZ8o2NzSC/PGRymUm/kpsWikZtmB8//Vc0w Q==; X-IronPort-AV: E=McAfee;i="6500,9779,10572"; a="300994704" X-IronPort-AV: E=Sophos;i="5.96,277,1665471600"; d="scan'208";a="300994704" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Dec 2022 19:08:50 -0800 X-IronPort-AV: E=McAfee;i="6500,9779,10572"; a="741605219" X-IronPort-AV: E=Sophos;i="5.96,277,1665471600"; d="scan'208";a="741605219" Received: from ppogotov-mobl.ger.corp.intel.com (HELO box.shutemov.name) ([10.252.62.152]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 26 Dec 2022 19:08:46 -0800 Received: by box.shutemov.name (Postfix, from userid 1000) id C95CE10BBB5; Tue, 27 Dec 2022 06:08:36 +0300 (+03) From: "Kirill A. Shutemov" To: Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: x86@kernel.org, Kostya Serebryany , Andrey Ryabinin , Andrey Konovalov , Alexander Potapenko , Taras Madan , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , Bharata B Rao , Jacob Pan , Ashok Raj , Linus Torvalds , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" , Catalin Marinas Subject: [PATCHv13 08/16] mm: Expose untagging mask in /proc/$PID/status Date: Tue, 27 Dec 2022 06:08:21 +0300 Message-Id: <20221227030829.12508-9-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.38.2 In-Reply-To: <20221227030829.12508-1-kirill.shutemov@linux.intel.com> References: <20221227030829.12508-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" Add a line in /proc/$PID/status to report untag_mask. It can be used to find out LAM status of the process from the outside. It is useful for debuggers. Signed-off-by: Kirill A. Shutemov Acked-by: Catalin Marinas --- arch/arm64/include/asm/mmu_context.h | 6 ++++++ arch/sparc/include/asm/mmu_context_64.h | 6 ++++++ arch/x86/include/asm/mmu_context.h | 6 ++++++ fs/proc/array.c | 6 ++++++ include/linux/mmu_context.h | 7 +++++++ 5 files changed, 31 insertions(+) diff --git a/arch/arm64/include/asm/mmu_context.h b/arch/arm64/include/asm/= mmu_context.h index 72dbd6400549..56911691bef0 100644 --- a/arch/arm64/include/asm/mmu_context.h +++ b/arch/arm64/include/asm/mmu_context.h @@ -288,6 +288,12 @@ void post_ttbr_update_workaround(void); unsigned long arm64_mm_context_get(struct mm_struct *mm); void arm64_mm_context_put(struct mm_struct *mm); =20 +#define mm_untag_mask mm_untag_mask +static inline unsigned long mm_untag_mask(struct mm_struct *mm) +{ + return -1UL >> 8; +} + #include =20 #endif /* !__ASSEMBLY__ */ diff --git a/arch/sparc/include/asm/mmu_context_64.h b/arch/sparc/include/a= sm/mmu_context_64.h index 7a8380c63aab..799e797c5cdd 100644 --- a/arch/sparc/include/asm/mmu_context_64.h +++ b/arch/sparc/include/asm/mmu_context_64.h @@ -185,6 +185,12 @@ static inline void finish_arch_post_lock_switch(void) } } =20 +#define mm_untag_mask mm_untag_mask +static inline unsigned long mm_untag_mask(struct mm_struct *mm) +{ + return -1UL >> adi_nbits(); +} + #include =20 #endif /* !(__ASSEMBLY__) */ diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_= context.h index 71581cb4811b..7f9f9978c811 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -103,6 +103,12 @@ static inline void dup_lam(struct mm_struct *oldmm, st= ruct mm_struct *mm) mm->context.untag_mask =3D oldmm->context.untag_mask; } =20 +#define mm_untag_mask mm_untag_mask +static inline unsigned long mm_untag_mask(struct mm_struct *mm) +{ + return mm->context.untag_mask; +} + static inline void mm_reset_untag_mask(struct mm_struct *mm) { mm->context.untag_mask =3D -1UL; diff --git a/fs/proc/array.c b/fs/proc/array.c index 49283b8103c7..d2a94eafe9a3 100644 --- a/fs/proc/array.c +++ b/fs/proc/array.c @@ -428,6 +428,11 @@ static inline void task_thp_status(struct seq_file *m,= struct mm_struct *mm) seq_printf(m, "THP_enabled:\t%d\n", thp_enabled); } =20 +static inline void task_untag_mask(struct seq_file *m, struct mm_struct *m= m) +{ + seq_printf(m, "untag_mask:\t%#lx\n", mm_untag_mask(mm)); +} + int proc_pid_status(struct seq_file *m, struct pid_namespace *ns, struct pid *pid, struct task_struct *task) { @@ -443,6 +448,7 @@ int proc_pid_status(struct seq_file *m, struct pid_name= space *ns, task_mem(m, mm); task_core_dumping(m, task); task_thp_status(m, mm); + task_untag_mask(m, mm); mmput(mm); } task_sig(m, task); diff --git a/include/linux/mmu_context.h b/include/linux/mmu_context.h index b9b970f7ab45..14b9c1fa05c4 100644 --- a/include/linux/mmu_context.h +++ b/include/linux/mmu_context.h @@ -28,4 +28,11 @@ static inline void leave_mm(int cpu) { } # define task_cpu_possible(cpu, p) cpumask_test_cpu((cpu), task_cpu_possib= le_mask(p)) #endif =20 +#ifndef mm_untag_mask +static inline unsigned long mm_untag_mask(struct mm_struct *mm) +{ + return -1UL; +} +#endif + #endif --=20 2.38.2