From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from an-out-0708.google.com ([209.85.132.242]) by canuck.infradead.org with esmtp (Exim 4.63 #1 (Red Hat Linux)) id 1Hoixr-0003gp-G0 for linux-mtd@lists.infradead.org; Thu, 17 May 2007 12:36:32 -0400 Received: by an-out-0708.google.com with SMTP id d17so146763and for ; Thu, 17 May 2007 09:36:29 -0700 (PDT) Message-ID: <93840d070705170936o7188807do17f29422f7e31404@mail.gmail.com> Date: Thu, 17 May 2007 22:06:28 +0530 From: "Sekhar Nori" To: "David Woodhouse" Subject: Re: Priority inversion when using MTD In-Reply-To: <1179409930.2859.495.camel@shinybook.infradead.org> MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Content-Disposition: inline References: <93840d070705170620x4a61007ap537ce877acfab488@mail.gmail.com> <1179409930.2859.495.camel@shinybook.infradead.org> Cc: linux-mtd@lists.infradead.org List-Id: Linux MTD discussion mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , On 5/17/07, David Woodhouse wrote: > On Thu, 2007-05-17 at 18:50 +0530, Sekhar Nori wrote: > > I have a high priority SCHED_FIFO task which runs out of a squashfs file system. > > When this process needs to fetch a page from the flash (due to demand paging), > > it is sometimes made to wait for another low priority SCHED_NORMAL > > task which is doing an erase on some other mtd partition. > ... > > Is there any way to avoid this scenario? Any help/pointers would be appreciated. > > mlockall(2) But doing so for all SCHED_FIFO tasks would make the system run out of memory :( - Sekhar Nori