From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from psmtp.com (na3sys010amx199.postini.com [74.125.245.199]) by kanga.kvack.org (Postfix) with SMTP id 8AB5C6B002B for ; Tue, 25 Sep 2012 17:29:49 -0400 (EDT) Date: Tue, 25 Sep 2012 14:29:48 -0700 From: Andrew Morton Subject: Re: [PATCH 05/10] mm, util: Use dup_user to duplicate user memory Message-Id: <20120925142948.6b062cb6.akpm@linux-foundation.org> In-Reply-To: <1347137279-17568-5-git-send-email-elezegarcia@gmail.com> References: <1347137279-17568-1-git-send-email-elezegarcia@gmail.com> <1347137279-17568-5-git-send-email-elezegarcia@gmail.com> Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org List-ID: To: Ezequiel Garcia Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, Pekka Enberg On Sat, 8 Sep 2012 17:47:54 -0300 Ezequiel Garcia wrote: > Previously the strndup_user allocation was being done through memdup_user, > and the caller was wrongly traced as being strndup_user > (the correct trace must report the caller of strndup_user). > > This is a common problem: in order to get accurate callsite tracing, > a utils function can't allocate through another utils function, > but instead do the allocation himself (or inlined). > > Here we fix this by creating an always inlined dup_user() function to > performed the real allocation and to be used by memdup_user and strndup_user. This patch increases util.o's text size by 238 bytes. A larger kernel with a worsened cache footprint. And we did this to get marginally improved tracing output? This sounds like a bad tradeoff to me. -- 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