Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751213Ab1D0EQi (ORCPT ); Wed, 27 Apr 2011 00:16:38 -0400 Received: from mail-wy0-f174.google.com ([74.125.82.174]:51584 "EHLO mail-wy0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750779Ab1D0EQh (ORCPT ); Wed, 27 Apr 2011 00:16:37 -0400 DomainKey-Signature: a=rsa-sha1; c=nofws; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :cc:content-type; b=UA7zZLAJJkO9wcd2u/l8Q/W8zS/O8xGs05kNPRQQETaQ1WrK4Zf7PZFx6kj45sMEB6 MCrM4MbRmUqaAdsL2JqYYInnp6139Eq3m+yr1qGlvwOyv68+Wnbjei5mJWcieNb2Z2GH Lyydk/c7ZmmTmx/uwGBHBrcGcJKSq8lrLSeS0= MIME-Version: 1.0 In-Reply-To: <20110427031844.GA5595@p183> References: <20110427031844.GA5595@p183> Date: Wed, 27 Apr 2011 00:16:35 -0400 Message-ID: Subject: Re: How to export information larger than PROC_BLOCK_SIZE via /proc file system? From: Jidong Xiao To: Alexey Dobriyan Cc: "Am??rico Wang" , Kernel development list Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1363 Lines: 32 On Tue, Apr 26, 2011 at 11:18 PM, Alexey Dobriyan wrote: > On Wed, Apr 27, 2011 at 11:00:32AM +0800, Am??rico Wang wrote: >> On Wed, Apr 27, 2011 at 8:54 AM, Jidong Xiao wrote: >> > Hi, >> > >> > I am tracing some data inside the kernel, and I plan to export the >> > tracing data through /proc file system. I created a file under /proc >> > file system, and I use cat to display the tracing data. However, every >> > time there is only 3072 bytes data displayed, which is the size >> > defined by PROC_BLOCK_SIZE. And I wonder that how to export >> > information more than that limit? Judging from the function >> > fs/proc/generic.c/proc_file_read(), if the size returned by my >> > read_proc function is large than a PAGE_SIZE, then I will get a >> > KERN_ERR message which says "proc_file_read: Apparent buffer >> > overflow!". Any help would be appreciated! >> > >> >> Why not switch to use debugfs? > > Or use seq_file/proc_create. > Oh, thank you two very much. After reading the related document, I feel seq_file is exactly what I am looking for. Regards Jidong -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/