From mboxrd@z Thu Jan 1 00:00:00 1970 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 AE358CCA481 for ; Wed, 22 Jun 2022 16:23:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1376531AbiFVQXz (ORCPT ); Wed, 22 Jun 2022 12:23:55 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:60104 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1376875AbiFVQXj (ORCPT ); Wed, 22 Jun 2022 12:23:39 -0400 Received: from mga17.intel.com (mga17.intel.com [192.55.52.151]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 1D35B3FBE5 for ; Wed, 22 Jun 2022 09:23:31 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1655915011; x=1687451011; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=CU7rCkgXezI1vM2ho8MmDRIt7VouvlyZWqM/6FmVbeI=; b=nnoNytrxZB+fqjpwNcP2EJB+dWIu0UCQeS7sF5e51yevoCTTyWxvn11T ojloXzVX4RBeDLNskb/Fh/Ad9oenxkR66XsGmaFApHY/LLfsw14mKYLN+ ugBMJ+XlsvCGXtYwm+6aEEkGqWWoVB5+2EDR4bjIfku7A3tcTmUL9Tp8g 10K7axyybLtUxXcPRxY2gKGA+fqt93PjwdwF1GOcYi8CXhda20lkJIX7h wMXbpN30mBzCu804EAbFLvA3ogyHZjV/m4r6hT68w4HI+vBRyQJchec3A Vg6V+CnQgMkT5B6yViIF+Ra0MT8kQYQ2Q7DIoIL4QrTLIB5KmOdzn2URR A==; X-IronPort-AV: E=McAfee;i="6400,9594,10386"; a="260898822" X-IronPort-AV: E=Sophos;i="5.92,212,1650956400"; d="scan'208";a="260898822" Received: from orsmga005.jf.intel.com ([10.7.209.41]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jun 2022 09:22:47 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.92,212,1650956400"; d="scan'208";a="764947851" Received: from black.fi.intel.com ([10.237.72.28]) by orsmga005.jf.intel.com with ESMTP; 22 Jun 2022 09:22:42 -0700 Received: by black.fi.intel.com (Postfix, from userid 1000) id 6A3F813C; Wed, 22 Jun 2022 19:22:43 +0300 (EEST) From: "Kirill A. Shutemov" To: Dave Hansen , Andy Lutomirski , Peter Zijlstra Cc: x86@kernel.org, Kostya Serebryany , Andrey Ryabinin , Andrey Konovalov , Alexander Potapenko , Dmitry Vyukov , "H . J . Lu" , Andi Kleen , Rick Edgecombe , linux-mm@kvack.org, linux-kernel@vger.kernel.org, "Kirill A. Shutemov" Subject: [PATCHv4 7/8] x86: Expose untagging mask in /proc/$PID/arch_status Date: Wed, 22 Jun 2022 19:22:29 +0300 Message-Id: <20220622162230.83474-8-kirill.shutemov@linux.intel.com> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220622162230.83474-1-kirill.shutemov@linux.intel.com> References: <20220622162230.83474-1-kirill.shutemov@linux.intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Add a line in /proc/$PID/arch_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 --- arch/x86/include/asm/mmu_context.h | 10 +++++ arch/x86/kernel/Makefile | 2 + arch/x86/kernel/fpu/xstate.c | 47 ----------------------- arch/x86/kernel/proc.c | 60 ++++++++++++++++++++++++++++++ 4 files changed, 72 insertions(+), 47 deletions(-) create mode 100644 arch/x86/kernel/proc.c diff --git a/arch/x86/include/asm/mmu_context.h b/arch/x86/include/asm/mmu_context.h index 05821534aadc..a6cded0f5e64 100644 --- a/arch/x86/include/asm/mmu_context.h +++ b/arch/x86/include/asm/mmu_context.h @@ -103,6 +103,11 @@ static inline void dup_lam(struct mm_struct *oldmm, struct mm_struct *mm) mm->context.untag_mask = oldmm->context.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 = -1UL; @@ -119,6 +124,11 @@ static inline void dup_lam(struct mm_struct *oldmm, struct mm_struct *mm) { } +static inline unsigned long mm_untag_mask(struct mm_struct *mm) +{ + return -1UL; +} + static inline void mm_reset_untag_mask(struct mm_struct *mm) { } diff --git a/arch/x86/kernel/Makefile b/arch/x86/kernel/Makefile index 4c8b6ae802ac..313f1d8e7783 100644 --- a/arch/x86/kernel/Makefile +++ b/arch/x86/kernel/Makefile @@ -141,6 +141,8 @@ obj-$(CONFIG_UNWINDER_GUESS) += unwind_guess.o obj-$(CONFIG_AMD_MEM_ENCRYPT) += sev.o +obj-$(CONFIG_PROC_FS) += proc.o + ### # 64 bit specific files ifeq ($(CONFIG_X86_64),y) diff --git a/arch/x86/kernel/fpu/xstate.c b/arch/x86/kernel/fpu/xstate.c index c8340156bfd2..838a6f0627fd 100644 --- a/arch/x86/kernel/fpu/xstate.c +++ b/arch/x86/kernel/fpu/xstate.c @@ -10,8 +10,6 @@ #include #include #include -#include -#include #include #include @@ -1745,48 +1743,3 @@ long fpu_xstate_prctl(int option, unsigned long arg2) return -EINVAL; } } - -#ifdef CONFIG_PROC_PID_ARCH_STATUS -/* - * Report the amount of time elapsed in millisecond since last AVX512 - * use in the task. - */ -static void avx512_status(struct seq_file *m, struct task_struct *task) -{ - unsigned long timestamp = READ_ONCE(task->thread.fpu.avx512_timestamp); - long delta; - - if (!timestamp) { - /* - * Report -1 if no AVX512 usage - */ - delta = -1; - } else { - delta = (long)(jiffies - timestamp); - /* - * Cap to LONG_MAX if time difference > LONG_MAX - */ - if (delta < 0) - delta = LONG_MAX; - delta = jiffies_to_msecs(delta); - } - - seq_put_decimal_ll(m, "AVX512_elapsed_ms:\t", delta); - seq_putc(m, '\n'); -} - -/* - * Report architecture specific information - */ -int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns, - struct pid *pid, struct task_struct *task) -{ - /* - * Report AVX512 state if the processor and build option supported. - */ - if (cpu_feature_enabled(X86_FEATURE_AVX512F)) - avx512_status(m, task); - - return 0; -} -#endif /* CONFIG_PROC_PID_ARCH_STATUS */ diff --git a/arch/x86/kernel/proc.c b/arch/x86/kernel/proc.c new file mode 100644 index 000000000000..9765b4d05ce4 --- /dev/null +++ b/arch/x86/kernel/proc.c @@ -0,0 +1,60 @@ +// SPDX-License-Identifier: GPL-2.0-only +#include +#include +#include +#include +#include + +/* + * Report the amount of time elapsed in millisecond since last AVX512 + * use in the task. + */ +static void avx512_status(struct seq_file *m, struct task_struct *task) +{ + unsigned long timestamp = READ_ONCE(task->thread.fpu.avx512_timestamp); + long delta; + + if (!timestamp) { + /* + * Report -1 if no AVX512 usage + */ + delta = -1; + } else { + delta = (long)(jiffies - timestamp); + /* + * Cap to LONG_MAX if time difference > LONG_MAX + */ + if (delta < 0) + delta = LONG_MAX; + delta = jiffies_to_msecs(delta); + } + + seq_put_decimal_ll(m, "AVX512_elapsed_ms:\t", delta); + seq_putc(m, '\n'); +} + +/* + * Report architecture specific information + */ +int proc_pid_arch_status(struct seq_file *m, struct pid_namespace *ns, + struct pid *pid, struct task_struct *task) +{ + struct mm_struct *mm; + unsigned long untag_mask = -1UL; + + /* + * Report AVX512 state if the processor and build option supported. + */ + if (cpu_feature_enabled(X86_FEATURE_AVX512F)) + avx512_status(m, task); + + mm = get_task_mm(task); + if (mm) { + untag_mask = mm_untag_mask(task->mm); + mmput(mm); + } + + seq_printf(m, "untag_mask:\t%#lx\n", untag_mask); + + return 0; +} -- 2.35.1