From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx176.postini.com [74.125.245.176]) by kanga.kvack.org (Postfix) with SMTP id AD4D36B00E7 for ; Mon, 14 May 2012 03:54:14 -0400 (EDT) Received: by vbbey12 with SMTP id ey12so7406538vbb.14 for ; Mon, 14 May 2012 00:54:13 -0700 (PDT) MIME-Version: 1.0 In-Reply-To: References: <1336054995-22988-1-git-send-email-svenkatr@ti.com> <4FA8CF5E.1070202@kernel.org> <4FA9BE10.1030007@kernel.org> From: mani Date: Mon, 14 May 2012 13:23:53 +0530 Message-ID: Subject: Re: [PATCHv2 00/16] [FS, MM, block, MMC]: eMMC High Priority Interrupt Feature Content-Type: multipart/alternative; boundary=20cf307cfe7a610c2404bffa64b2 Sender: owner-linux-mm@kvack.org List-ID: To: Minchan Kim Cc: linux-mmc@vger.kernel.org, linux-mm@kvack.org, linux-fsdevel@vger.kernel.org, linux-omap@vger.kernel.org, linux-kernel@vger.kernel.org, svenkatr@ti.com --20cf307cfe7a610c2404bffa64b2 Content-Type: text/plain; charset=ISO-8859-1 Dear Kim, I have a query here .. > > My point is that it would be better for read to not preempt > write-for-page_reclaim. > And we can identify it by PG_reclaim. You can get the idea. > > I think If there is no page available then no read will proceed. When read request comes it reclaim the pages (starts the write if syncable pages ) and get back after reclaiming the pages. Only then a read request will come to the MMC subsystem. And i think the reclaim algorithm will reclaim some substantial amount of pages at a time instead of a single page. So if we get few pages during the reclamation so there will be no problem in halting the another write ops for proceeding the reads ? Can we think of a scenario when we are reclaiming the pages and write ops is going on where as a high priority read for the interrupt handler is pending ? Please correct me if i am wrong. Thanks & Regards Manish --20cf307cfe7a610c2404bffa64b2 Content-Type: text/html; charset=ISO-8859-1 Dear Kim,

I have a query here ..

My point is that it would be better for read to not preempt write-for-page_reclaim.
And we can identify it by PG_reclaim. You can get the idea.

I think If there is no page available then no read will proceed.
When read request comes it reclaim the pages (starts the write if syncable pages ) and get back after reclaiming the pages.
Only then a read request will come to the MMC subsystem.
And i think the reclaim algorithm will reclaim some substantial amount of pages at a time instead of a single page.
So if we get few pages during the reclamation so there will be no problem in halting the another write ops for proceeding the reads ?

Can we think of a scenario when we are reclaiming the pages and write ops is going on where as a high priority read for the interrupt handler is pending ?

Please correct me if i am wrong.

Thanks & Regards
Manish --20cf307cfe7a610c2404bffa64b2-- -- 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/ . Fight unfair telecom internet charges in Canada: sign http://stopthemeter.ca/ Don't email: email@kvack.org