From: Sedat Dilek Subject: Re: jbd2: don't wake kjournald unnecessarily Date: Sun, 20 Jan 2013 00:44:31 +0100 Message-ID: Reply-To: sedat.dilek@gmail.com Mime-Version: 1.0 Content-Type: multipart/mixed; boundary=047d7b6777f239b54204d3accf13 Cc: Jan Kara , linux-fsdevel , Ext4 Developers List , "Theodore Ts'o" , LKML , linux-next To: Eric Sandeen Return-path: Sender: linux-next-owner@vger.kernel.org List-Id: linux-ext4.vger.kernel.org --047d7b6777f239b54204d3accf13 Content-Type: text/plain; charset=UTF-8 Hi, I and some others hit a similiar problem in Linux-Next (next-20130118), please see [1] and [2]. [3] has a interim analyze of my problems. After suspecting the problem was caused by TTY-NEXT, it turned out to be a JBD2 problem finally. The freezer/pm_test was helpful to hit the issue (Thanks Rafael for the hint!). So, the issue has two faces: TTY and JBD2. [4] gives a list and URLs of the patches I had to apply to have a clean system again. After applying the two TTY patches (without Eric's JBD2-fix!) the call-trace after freezer/pm_test looked like this; [ 433.527986] PM: Syncing filesystems ... done. [ 433.843761] PM: Preparing system for mem sleep [ 436.306002] Freezing user space processes ... [ 456.304956] Freezing of tasks failed after 20.01 seconds (1 tasks refusing to freeze, wq_busy=0): [ 456.305060] Cache I/O D ffffffff8180d780 0 2132 1 0x00000004 [ 456.305065] ffff88007b9dfe18 0000000000000046 ffff88007b9dfdc8 0000000300000001 [ 456.305069] ffff880097e21720 ffff88007b9dffd8 ffff88007b9dffd8 ffff88007b9dffd8 [ 456.305072] ffff880119b32e40 ffff880097e21720 ffff88007b9dfe28 ffff880118077800 [ 456.305076] Call Trace: [ 456.305085] [] schedule+0x29/0x70 [ 456.305089] [] jbd2_log_wait_commit+0xcd/0x1a0 [ 456.305094] [] ? add_wait_queue+0x60/0x60 [ 456.305098] [] ext4_sync_file+0x205/0x380 [ 456.305103] [] do_fsync+0x5d/0x90 [ 456.305108] [] ? sys_write+0x6b/0xa0 [ 456.305111] [] sys_fsync+0x10/0x20 [ 456.305114] [] system_call_fastpath+0x1a/0x1f [ 456.305122] [ 456.305124] Restarting tasks ... done. [ 456.315056] video LNXVIDEO:00: Restoring backlight state After applying Eric's patch [5], I could not hit the call-trace again. NOTE: The patch is from December 2012 and is not shipped in latest Linux-Next. The attached testcase script was helpful to force the call-trace. I have run 50 loops of it w/o an issue! Feel free to add a Reported-by/Tested-by. ( The issue kept me busy for the last days. ) Regards, - Sedat - [1] http://marc.info/?t=135283664600002&r=1&w=2 [2] http://marc.info/?t=135862023700004&r=1&w=2 [3] http://marc.info/?l=linux-kernel&m=135862010419101&w=2 [4] http://marc.info/?l=linux-next&m=135863550923093&w=2 [5] http://patchwork.ozlabs.org/patch/207237/ --047d7b6777f239b54204d3accf13 Content-Type: application/x-sh; name="run_pm-test_v2.sh" Content-Disposition: attachment; filename="run_pm-test_v2.sh" Content-Transfer-Encoding: base64 X-Attachment-Id: f_hc5e8oim0 IyEvYmluL2Jhc2gKCiMgSEVMUAojIFsxXSBodHRwOi8vZ2l0Lmtlcm5lbC5vcmcvP3A9bGludXgv a2VybmVsL2dpdC90b3J2YWxkcy9saW51eC5naXQ7YT1ibG9iO2Y9RG9jdW1lbnRhdGlvbi9wb3dl ci9iYXNpYy1wbS1kZWJ1Z2dpbmcudHh0CiMgWzJdIGh0dHA6Ly9naXQua2VybmVsLm9yZy8/cD1s aW51eC9rZXJuZWwvZ2l0L3RvcnZhbGRzL2xpbnV4LmdpdDthPWJsb2I7Zj1Eb2N1bWVudGF0aW9u L3Bvd2VyL2ZyZWV6aW5nLW9mLXRhc2tzLnR4dAoKIyBQUkVSRVE6IEtlcm5lbCBERUJVRyBvcHRp b25zCiMgQ09ORklHX1BNX0RFQlVHPXkKIyBDT05GSUdfRVhUNF9ERUJVRz15CiMgQ09ORklHX0pC RDJfREVCVUc9eQoKZXhwb3J0IExBTkc9QwpleHBvcnQgTENfQUxMPUMKCiMgRGVmYXVsdCB2YWx1 ZSBvZiBodW5nX3Rhc2tfdGltZW91dF9zZWNzIGlzIDEyMCBbc2Vjc10KU0VDUz0iMCIKCiMgUG9z c2libGUgdHlwZXM6IG5vbmUgY29yZSBwcm9jZXNzb3JzIHBsYXRmb3JtIGRldmljZXMgZnJlZXpl cgpQTV9URVNUX1RZUEU9ImZyZWV6ZXIiCgojIENvdW50ZXIgYW5kIGxvb3BzCkNPVU5URVI9IjAi CkxPT1BTPSIxMCIKCmVjaG8gIiRTRUNTIiA+IC9wcm9jL3N5cy9rZXJuZWwvaHVuZ190YXNrX3Rp bWVvdXRfc2VjcwoKZWNobyAiJFBNX1RFU1RfVFlQRSIgPiAvc3lzL3Bvd2VyL3BtX3Rlc3QKCndo aWxlIFsgJENPVU5URVIgLWx0ICRMT09QUyBdOyBkbwogICAgZWNobyBbIHBtX3Rlc3QvZnJlZXpl cjogUnVuICRDT1VOVEVSIF0KICAgIGVjaG8gbWVtID4gL3N5cy9wb3dlci9zdGF0ZSAmJiBzbGVl cCAxCiAgICBlY2hvIFsgcG1fdGVzdC9mcmVlemVyOiBPSyAkQ09VTlRFUiBdCiAgICBsZXQgQ09V TlRFUj1DT1VOVEVSKzEKZG9uZQo= --047d7b6777f239b54204d3accf13--