From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pg0-f71.google.com (mail-pg0-f71.google.com [74.125.83.71]) by kanga.kvack.org (Postfix) with ESMTP id 31AD82806DF for ; Thu, 30 Mar 2017 10:47:22 -0400 (EDT) Received: by mail-pg0-f71.google.com with SMTP id a72so47382639pge.10 for ; Thu, 30 Mar 2017 07:47:22 -0700 (PDT) Received: from EUR01-HE1-obe.outbound.protection.outlook.com (mail-he1eur01on0137.outbound.protection.outlook.com. [104.47.0.137]) by mx.google.com with ESMTPS id q9si2345870plk.300.2017.03.30.07.47.20 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-SHA bits=128/128); Thu, 30 Mar 2017 07:47:21 -0700 (PDT) Subject: Re: [PATCH 1/4] mm/vmalloc: allow to call vfree() in atomic context References: <20170330102719.13119-1-aryabinin@virtuozzo.com> <2cfc601e-3093-143e-b93d-402f330a748a@vmware.com> From: Andrey Ryabinin Message-ID: Date: Thu, 30 Mar 2017 17:48:39 +0300 MIME-Version: 1.0 In-Reply-To: <2cfc601e-3093-143e-b93d-402f330a748a@vmware.com> Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Thomas Hellstrom , akpm@linux-foundation.org Cc: penguin-kernel@I-love.SAKURA.ne.jp, linux-kernel@vger.kernel.org, mhocko@kernel.org, linux-mm@kvack.org, hpa@zytor.com, chris@chris-wilson.co.uk, hch@lst.de, mingo@elte.hu, jszhang@marvell.com, joelaf@google.com, joaodias@google.com, willy@infradead.org, tglx@linutronix.de, stable@vger.kernel.org On 03/30/2017 03:00 PM, Thomas Hellstrom wrote: >> >> if (unlikely(nr_lazy > lazy_max_pages())) >> - try_purge_vmap_area_lazy(); > > Perhaps a slight optimization would be to schedule work iff > !mutex_locked(&vmap_purge_lock) below? > Makes sense, we don't need to spawn workers if we already purging. From: Andrey Ryabinin Subject: mm/vmalloc: allow to call vfree() in atomic context fix Don't spawn worker if we already purging. Signed-off-by: Andrey Ryabinin --- mm/vmalloc.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/mm/vmalloc.c b/mm/vmalloc.c index ea1b4ab..88168b8 100644 --- a/mm/vmalloc.c +++ b/mm/vmalloc.c @@ -737,7 +737,8 @@ static void free_vmap_area_noflush(struct vmap_area *va) /* After this point, we may free va at any time */ llist_add(&va->purge_list, &vmap_purge_list); - if (unlikely(nr_lazy > lazy_max_pages())) + if (unlikely(nr_lazy > lazy_max_pages()) && + !mutex_is_locked(&vmap_purge_lock)) schedule_work(&purge_vmap_work); } -- 2.10.2 -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org