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Date: Tue, 13 Feb 2001 00:05:50 -0200 (BRST)
From: Marcelo Tosatti <marcelo@conectiva.com.br>
To: george anzinger <george@mvista.com>
cc: Rasmus Andersen <rasmus@jaquet.dk>, Rik van Riel <riel@conectiva.com.br>,
        torvalds@transmeta.com, linux-kernel@vger.kernel.org,
        linux-mm@kvack.org
Subject: Re: [PATCH] guard mm->rss with page_table_lock (241p11)
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On Mon, 12 Feb 2001, george anzinger wrote:

> Excuse me if I am off base here, but wouldn't an atomic operation be
> better here.  There are atomic inc/dec and add/sub macros for this.  It
> just seems that that is all that is needed here (from inspection of the
> patch).

Most functions which touch mm->rss already hold mm->page_table_lock (also
this functions are called more often and they use more CPU).

Making those functions use an atomic instruction just to optimize the
functions which do not lock mm->page_table_lock is not a good tradeoff.


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