From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-lf0-f67.google.com ([209.85.215.67]:34667 "EHLO mail-lf0-f67.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756546AbcJQHV6 (ORCPT ); Mon, 17 Oct 2016 03:21:58 -0400 From: Amir Goldstein Subject: [PATCH v3] xfs_io: add command line option -i to start an idle thread Date: Mon, 17 Oct 2016 10:20:51 +0300 Message-Id: <1476688851-32647-1-git-send-email-amir73il@gmail.com> Sender: linux-xfs-owner@vger.kernel.org List-ID: List-Id: xfs To: Dave Chinner Cc: Christoph Hellwig , linux-xfs@vger.kernel.org, fstests@vger.kernel.org xfs_io -i will start by spawning an idle thread. The purpose of this idle thread is to test io from a multi threaded process. With single threaded process, the file table is not shared and file structs are not reference counted. Spawning an idle thread can help detecting file struct reference leaks. Signed-off-by: Amir Goldstein Reviewed-by: Christoph Hellwig --- io/Makefile | 2 +- io/init.c | 35 +++++++++++++++++++++++++++++++++-- man/man8/xfs_io.8 | 8 +++++++- 3 files changed, 41 insertions(+), 4 deletions(-) diff --git a/io/Makefile b/io/Makefile index 1997ca9..032a8c7 100644 --- a/io/Makefile +++ b/io/Makefile @@ -13,7 +13,7 @@ CFILES = init.c \ mmap.c open.c parent.c pread.c prealloc.c pwrite.c seek.c shutdown.c \ sync.c truncate.c reflink.c -LLDLIBS = $(LIBXCMD) $(LIBHANDLE) +LLDLIBS = $(LIBXCMD) $(LIBHANDLE) $(LIBPTHREAD) LTDEPENDENCIES = $(LIBXCMD) $(LIBHANDLE) LLDFLAGS = -static-libtool-libs diff --git a/io/init.c b/io/init.c index 6b88cc6..2db48a2 100644 --- a/io/init.c +++ b/io/init.c @@ -16,6 +16,7 @@ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ +#include #include "platform_defs.h" #include "command.h" #include "input.h" @@ -25,6 +26,7 @@ char *progname; int exitcode; int expert; +int idlethread; size_t pagesize; struct timeval stopwatch; @@ -32,7 +34,7 @@ void usage(void) { fprintf(stderr, - _("Usage: %s [-adfmnrRstVx] [-p prog] [-c cmd]... file\n"), + _("Usage: %s [-adfimnrRstTVx] [-p prog] [-c cmd]... file\n"), progname); exit(1); } @@ -141,7 +143,7 @@ init( pagesize = getpagesize(); gettimeofday(&stopwatch, NULL); - while ((c = getopt(argc, argv, "ac:dFfmp:nrRstTVx")) != EOF) { + while ((c = getopt(argc, argv, "ac:dFfimp:nrRstTVx")) != EOF) { switch (c) { case 'a': flags |= IO_APPEND; @@ -158,6 +160,9 @@ init( case 'f': flags |= IO_CREAT; break; + case 'i': + idlethread = 1; + break; case 'm': mode = strtoul(optarg, &sp, 0); if (!sp || sp == optarg) { @@ -213,12 +218,38 @@ init( add_check_command(init_check_command); } +/* + * The purpose of this idle thread is to test io from a multi threaded process. + * With single threaded process, the file table is not shared and file structs + * are not reference counted. Spawning an idle thread can help detecting file + * struct reference leaks. + */ +void * +idle_loop(void *arg) +{ + for (;;) + pause(); +} + +void +start_idle_thread() +{ + pthread_t t; + + if (pthread_create(&t, NULL, idle_loop, NULL)) { + fprintf(stderr, "Error creating idle thread\n"); + exit(1); + } +} + int main( int argc, char **argv) { init(argc, argv); + if (idlethread) + start_idle_thread(); command_loop(); return exitcode; } diff --git a/man/man8/xfs_io.8 b/man/man8/xfs_io.8 index eb7b878..885df7f 100644 --- a/man/man8/xfs_io.8 +++ b/man/man8/xfs_io.8 @@ -4,7 +4,7 @@ xfs_io \- debug the I/O path of an XFS filesystem .SH SYNOPSIS .B xfs_io [ -.B \-adfmrRstxT +.B \-adfimrRstxT ] [ .B \-c .I cmd @@ -51,6 +51,12 @@ read-only, initially. This is required if .I file is immutable or append-only. .TP +.B \-i +Start an idle thread. The purpose of this idle thread is to test io +from a multi threaded process. With single threaded process, +the file table is not shared and file structs are not reference counted. +Spawning an idle thread can help detecting file struct reference leaks. +.TP .B \-x Expert mode. Dangerous commands are only available in this mode. These commands also tend to require additional privileges. -- 2.7.4