Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753601Ab3HWAwW (ORCPT ); Thu, 22 Aug 2013 20:52:22 -0400 Received: from mail-vc0-f175.google.com ([209.85.220.175]:43791 "EHLO mail-vc0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752700Ab3HWAwV (ORCPT ); Thu, 22 Aug 2013 20:52:21 -0400 MIME-Version: 1.0 From: Andy Lutomirski Date: Thu, 22 Aug 2013 17:52:00 -0700 Message-ID: Subject: Finding out who's holding a lock? To: "linux-kernel@vger.kernel.org" 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: 563 Lines: 13 My program is occasionally seeing slow page faults. latencytop says they're slow because they're waiting for read access to mmap_sem, but latencytop isn't showing any other thread in the process blocking. Is there any straightforward way to find out who called down_write on mmap_sem when down_read is slow? --Andy -- 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/