Received: by 2002:a25:8b91:0:0:0:0:0 with SMTP id j17csp129758ybl;
        Wed, 11 Dec 2019 15:14:11 -0800 (PST)
X-Google-Smtp-Source: APXvYqzC7MbBCt0NwWtseDRx2RkK0+Yi6LSTZtNOwAzqjNaX9hb+ipYuuxXQ4Swtq+N+TfCYAqTS
X-Received: by 2002:a05:6830:1d91:: with SMTP id y17mr4299159oti.276.1576106051831;
        Wed, 11 Dec 2019 15:14:11 -0800 (PST)
ARC-Seal: i=1; a=rsa-sha256; t=1576106051; cv=none;
        d=google.com; s=arc-20160816;
        b=q7G5mcp5blWOavHG0+7umE9Oedp3emM8habdYf/ptQ+968OrwmvnRMAmaMpo32Z9/U
         pOy9jezmpsXDh2xQMnnZhxj1OImYX6/G6xAJi/VBoz4k2pIEZf7/RciWNtzV9yXpFZ4A
         OsV1F0YVIEYT0PZghVlfiX8/djzuNpVasEIuxcbN1tC80Gna40Zv41RT4Z39HgR5ojMC
         x+HtrZ03r+IWBgCkuxKIFcZJ9VVuYr/oQRflmgZgGwbIN/wFku8M0qiF2b1A9bUMn2th
         ph2XRFSklpo9Bni6owLo8N2kYF10A7RelNdM6UlwAGmpk4PgmW2amOVVvcdFLVUcaK9X
         q3HA==
ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816;
        h=list-id:precedence:sender:mime-version:user-agent:message-id
         :in-reply-to:date:references:subject:cc:to:from;
        bh=eOu0rv71H1+gmoFMX6Qt4yogzzPaIvAQcqdlmNTBiHs=;
        b=T5CuFvwz3O1dml1FbLYI1x+OtifygRp/Lz/yfm+2PLeO3eGmtO2a8+cnm6Ueo7cMmx
         4JxzYo/y34yThkD3Ayr6JuH3rLWQ6ydKhMs+ky5knT/s+Ar80cqrWKQ72jRaPpMkfkku
         oaKmLUDNrpkdmaOywUac0yzvdguDk7q2lYIH6gqDyeE9kuW+nurQD/rNtN08VF/pm4Dz
         y4BUpjaWr5YqO4J600UnMtVraF0L1rbxKQPCqt6uGrFkNoznpDQw2Vdmmdd8nITDa86h
         h3Kcc+Stz6SsWN4clc7fVPzj81A4CTpxvR7QMx5Bb/R41DlqaCbuUm3mZ1g7r3LwoW3U
         k66A==
ARC-Authentication-Results: i=1; mx.google.com;
       spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org;
       dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com
Return-Path: <linux-kernel-owner@vger.kernel.org>
Received: from vger.kernel.org (vger.kernel.org. [209.132.180.67])
        by mx.google.com with ESMTP id d13si2044950otp.196.2019.12.11.15.13.52;
        Wed, 11 Dec 2019 15:14:11 -0800 (PST)
Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
Authentication-Results: mx.google.com;
       spf=pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org;
       dmarc=fail (p=NONE sp=NONE dis=NONE) header.from=intel.com
Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand
        id S1726970AbfLKXL6 (ORCPT <rfc822;epontan@gmail.com> + 99 others);
        Wed, 11 Dec 2019 18:11:58 -0500
Received: from mga14.intel.com ([192.55.52.115]:60021 "EHLO mga14.intel.com"
        rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP
        id S1726589AbfLKXL6 (ORCPT <rfc822;linux-kernel@vger.kernel.org>);
        Wed, 11 Dec 2019 18:11:58 -0500
X-Amp-Result: SKIPPED(no attachment in message)
X-Amp-File-Uploaded: False
Received: from fmsmga004.fm.intel.com ([10.253.24.48])
  by fmsmga103.fm.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 11 Dec 2019 15:05:48 -0800
X-ExtLoop1: 1
X-IronPort-AV: E=Sophos;i="5.69,303,1571727600"; 
   d="scan'208";a="238734369"
Received: from tassilo.jf.intel.com (HELO tassilo.localdomain) ([10.7.201.21])
  by fmsmga004.fm.intel.com with ESMTP; 11 Dec 2019 15:05:48 -0800
Received: by tassilo.localdomain (Postfix, from userid 1000)
        id 608573002C5; Wed, 11 Dec 2019 15:05:48 -0800 (PST)
From:   Andi Kleen <ak@linux.intel.com>
To:     Waiman Long <longman@redhat.com>
Cc:     Mike Kravetz <mike.kravetz@oracle.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-mm@kvack.org,
        Matthew Wilcox <willy@infradead.org>
Subject: Re: [PATCH v2] hugetlbfs: Disable softIRQ when taking hugetlb_lock
References: <20191211194615.18502-1-longman@redhat.com>
Date:   Wed, 11 Dec 2019 15:05:48 -0800
In-Reply-To: <20191211194615.18502-1-longman@redhat.com> (Waiman Long's
        message of "Wed, 11 Dec 2019 14:46:15 -0500")
Message-ID: <87a77yv4xf.fsf@linux.intel.com>
User-Agent: Gnus/5.13 (Gnus v5.13) Emacs/26.2 (gnu/linux)
MIME-Version: 1.0
Content-Type: text/plain
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk
List-ID: <linux-kernel.vger.kernel.org>
X-Mailing-List: linux-kernel@vger.kernel.org

Waiman Long <longman@redhat.com> writes:
>
> Currently, only free_huge_page() is known to be called from softIRQ
> context.

Called from a timer?

Perhaps just move that to a work queue instead.

That seems preferable than to increase softirq latency.

-Andi