Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752916AbaBMB3A (ORCPT ); Wed, 12 Feb 2014 20:29:00 -0500 Received: from mail9.hitachi.co.jp ([133.145.228.44]:45566 "EHLO mail9.hitachi.co.jp" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751664AbaBMB24 (ORCPT ); Wed, 12 Feb 2014 20:28:56 -0500 X-AuditID: 85900ec0-d0927b9000001514-09-52fc1fd5a1f4 Subject: [PATCH -tip RESEND 0/2] ftrace: Introduce the new I/F "nr_saved_cmdlines" To: linux-kernel@vger.kernel.org, Steven Rostedt From: Yoshihiro YUNOMAE Cc: Hidehiro Kawai , Frederic Weisbecker , Masami Hiramatsu , Ingo Molnar , yrl.pp-manager.tt@hitachi.com Date: Thu, 13 Feb 2014 10:28:52 +0900 Message-ID: <20140213012852.15283.50473.stgit@yunodevel> User-Agent: StGit/0.16 MIME-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: 7bit X-Brightmail-Tracker: AAAAAA== Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Hi Steven, This patch set introduces the new I/F "nr_saved_cmdlines" for increasing the number of saved cmdlines. Current saved_cmdlines can store just 128 command names and PIDs, but process names are often lost like <...> when we read trace data. If the process exists, we can get the name by using ps command. However, if the process already has not existed, we cannot get the name. To solve this issue, we introduce the new I/F "nr_saved_cmdlines" to expand the max number of saved command line names. This I/F is very simple. If we write a number to nr_saved_cmdlines, the number of command name will be stored. And, if we read the I/F, we can get current maximum number of command name. The default number is 128 which is current default number, so this patch does not change the usage of memory for saved_cmdlines when we boot kernel. Thanks! Note: This patch set was rebased for current tip ftrace-core kernel. --- Yoshihiro YUNOMAE (2): ftrace: Make saved_cmdlines use seq_read ftrace: Introduce nr_saved_cmdlines I/F kernel/trace/trace.c | 296 +++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 241 insertions(+), 55 deletions(-) -- Yoshihiro YUNOMAE Software Platform Research Dept. Linux Technology Center Hitachi, Ltd., Yokohama Research Laboratory E-mail: yoshihiro.yunomae.ez@hitachi.com -- 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/