Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753846Ab0LGL0D (ORCPT ); Tue, 7 Dec 2010 06:26:03 -0500 Received: from bld-mail15.adl6.internode.on.net ([150.101.137.100]:59252 "EHLO mail.internode.on.net" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1752681Ab0LGL0B (ORCPT ); Tue, 7 Dec 2010 06:26:01 -0500 Date: Tue, 7 Dec 2010 22:25:55 +1100 From: Dave Chinner To: Nick Piggin Cc: linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org Subject: Re: [PATCH 00/46] rcu-walk and dcache scaling Message-ID: <20101207112555.GE16103@dastard> References: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: User-Agent: Mutt/1.5.20 (2009-06-14) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8046 Lines: 133 On Sat, Nov 27, 2010 at 09:15:58PM +1100, Nick Piggin wrote: > > git://git.kernel.org/pub/scm/linux/kernel/git/npiggin/linux-npiggin.git vfs-scale-working > > Here is an new set of vfs patches for review, not that there was much interest > last time they were posted. It is structured like: > > * preparation patches > * introduce new locks to take over dcache_lock, then remove it > * cleaning up and reworking things for new locks > * rcu-walk path walking > * start on some fine grained locking steps Just got this set of traces doing an 8-way parallel remove of 50 million inodes at about 40M inodes unlinked: [ 5954.061633] BUG: sleeping function called from invalid context at arch/x86/mm/fault.c:1081 [ 5954.062466] in_atomic(): 0, irqs_disabled(): 1, pid: 2927, name: rm [ 5954.063122] 3 locks held by rm/2927: [ 5954.063476] #0: (&sb->s_type->i_mutex_key#12/1){+.+.+.}, at: [] do_rmdir+0x81/0x130 [ 5954.064014] #1: (&sb->s_type->i_mutex_key#12){+.+.+.}, at: [] vfs_rmdir+0x58/0xe0 [ 5954.064014] #2: (rcu_read_lock){.+.+..}, at: [] shrink_dentry_list+0x0/0x430 [ 5954.064014] irq event stamp: 1484376719 [ 5954.064014] hardirqs last enabled at (1484376719): [] __call_rcu+0xd7/0x1a0 [ 5954.064014] hardirqs last disabled at (1484376718): [] __call_rcu+0x4a/0x1a0 [ 5954.064014] softirqs last enabled at (1484376586): [] __do_softirq+0x161/0x270 [ 5954.064014] softirqs last disabled at (1484376581): [] call_softirq+0x1c/0x50 [ 5954.064014] Pid: 2927, comm: rm Not tainted 2.6.37-rc4-dgc+ #794 [ 5954.064014] Call Trace: [ 5954.064014] [] ? print_irqtrace_events+0xd0/0xe0 [ 5954.064014] [] __might_sleep+0xf5/0x130 [ 5954.064014] [] do_page_fault+0x103/0x4f0 [ 5954.064014] [] ? pvclock_clocksource_read+0x58/0xd0 [ 5954.064014] [] ? pvclock_clocksource_read+0x58/0xd0 [ 5954.064014] [] ? pvclock_clocksource_read+0x58/0xd0 [ 5954.064014] [] ? trace_hardirqs_off_thunk+0x3a/0x3c [ 5954.064014] [] ? usage_match+0x0/0x20 [ 5954.064014] [] page_fault+0x25/0x30 [ 5954.064014] [] ? usage_match+0x0/0x20 [ 5954.064014] [] ? __bfs+0xc8/0x260 [ 5954.064014] [] ? __bfs+0x23/0x260 [ 5954.064014] [] find_usage_backwards+0x42/0x80 [ 5954.064014] [] check_usage_backwards+0x64/0xf0 [ 5954.064014] [] ? save_stack_trace+0x2f/0x50 [ 5954.064014] [] ? check_usage_backwards+0x0/0xf0 [ 5954.064014] [] mark_lock+0x1a9/0x440 [ 5954.064014] [] __lock_acquire+0x5a9/0x14b0 [ 5954.064014] [] ? __lock_acquire+0x336/0x14b0 [ 5954.064014] [] ? pvclock_clocksource_read+0x58/0xd0 [ 5954.064014] [] lock_acquire+0xb4/0x140 [ 5954.064014] [] ? shrink_dentry_list+0x5c/0x430 [ 5954.064014] [] _raw_spin_lock+0x36/0x70 [ 5954.064014] [] ? shrink_dentry_list+0x5c/0x430 [ 5954.064014] [] shrink_dentry_list+0x5c/0x430 [ 5954.064014] [] ? shrink_dentry_list+0x0/0x430 [ 5954.064014] [] ? do_raw_spin_unlock+0x5e/0xb0 [ 5954.064014] [] __shrink_dcache_sb+0x13d/0x1c0 [ 5954.064014] [] shrink_dcache_parent+0x32f/0x390 [ 5954.064014] [] dentry_unhash+0x3d/0x70 [ 5954.064014] [] vfs_rmdir+0x60/0xe0 [ 5954.064014] [] do_rmdir+0x113/0x130 [ 5954.064014] [] ? sysret_check+0x2e/0x69 [ 5954.064014] [] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 5954.064014] [] sys_unlinkat+0x35/0x40 [ 5954.064014] [] system_call_fastpath+0x16/0x1b [ 5954.092916] BUG: unable to handle kernel NULL pointer dereference at (null) [ 5954.093806] IP: [] __bfs+0xc8/0x260 [ 5954.094331] PGD 1084e5067 PUD 102368067 PMD 0 [ 5954.094830] Oops: 0000 [#1] SMP [ 5954.095194] last sysfs file: /sys/devices/system/cpu/online [ 5954.095760] CPU 6 [ 5954.095954] Modules linked in: [ 5954.096319] [ 5954.096483] Pid: 2927, comm: rm Not tainted 2.6.37-rc4-dgc+ #794 /Bochs [ 5954.096665] RIP: 0010:[] [] __bfs+0xc8/0x260 [ 5954.096665] RSP: 0018:ffff8801175539a8 EFLAGS: 00010046 [ 5954.096665] RAX: ffffffff8267d980 RBX: ffffffff8267d980 RCX: ffff880117553a48 [ 5954.096665] RDX: ffff8801175539d0 RSI: 0000000000000000 RDI: ffff880117553a48 [ 5954.096665] RBP: ffff880117553a08 R08: 0000000000000000 R09: 0000000000000000 [ 5954.096665] R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 [ 5954.096665] R13: ffffffff810b8e20 R14: ffff880117553a90 R15: 0000000000000000 [ 5954.096665] FS: 00007f4594cf3700(0000) GS:ffff8800dfa00000(0000) knlGS:0000000000000000 [ 5954.096665] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 5954.096665] CR2: 00007f2f21e89c60 CR3: 0000000110b0f000 CR4: 00000000000006e0 [ 5954.096665] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 5954.096665] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 5954.096665] Process rm (pid: 2927, threadinfo ffff880117552000, task ffff88010ff10b00) [ 5954.096665] Stack: [ 5954.096665] ffffffff8267d868 00007fffa02d1428 ffff8800ffffffff ffff880100000000 [ 5954.096665] 000000000000b720 ffff880117553a48 ffffffff8267d868 ffff880117553a48 [ 5954.096665] 0000000000000000 ffff88010ff10b00 0000000000000000 ffffffff81dacba0 [ 5954.096665] Call Trace: [ 5954.096665] [] find_usage_backwards+0x42/0x80 [ 5954.096665] [] check_usage_backwards+0x64/0xf0 [ 5954.096665] [] ? save_stack_trace+0x2f/0x50 [ 5954.096665] [] ? check_usage_backwards+0x0/0xf0 [ 5954.096665] [] mark_lock+0x1a9/0x440 [ 5954.096665] [] __lock_acquire+0x5a9/0x14b0 [ 5954.096665] [] ? __lock_acquire+0x336/0x14b0 [ 5954.096665] [] ? pvclock_clocksource_read+0x58/0xd0 [ 5954.096665] [] lock_acquire+0xb4/0x140 [ 5954.096665] [] ? shrink_dentry_list+0x5c/0x430 [ 5954.096665] [] _raw_spin_lock+0x36/0x70 [ 5954.096665] [] ? shrink_dentry_list+0x5c/0x430 [ 5954.096665] [] shrink_dentry_list+0x5c/0x430 [ 5954.096665] [] ? shrink_dentry_list+0x0/0x430 [ 5954.096665] [] ? do_raw_spin_unlock+0x5e/0xb0 [ 5954.096665] [] __shrink_dcache_sb+0x13d/0x1c0 [ 5954.096665] [] shrink_dcache_parent+0x32f/0x390 [ 5954.096665] [] dentry_unhash+0x3d/0x70 [ 5954.096665] [] vfs_rmdir+0x60/0xe0 [ 5954.096665] [] do_rmdir+0x113/0x130 [ 5954.096665] [] ? sysret_check+0x2e/0x69 [ 5954.096665] [] ? trace_hardirqs_on_thunk+0x3a/0x3f [ 5954.096665] [] sys_unlinkat+0x35/0x40 [ 5954.096665] [] system_call_fastpath+0x16/0x1b [ 5954.096665] Code: 0a 89 05 dc 0f a8 01 48 8b 41 10 48 85 c0 0f 84 1f 01 00 00 48 8d 98 70 01 00 00 48 05 80 01 00 00 45 85 c0 48 0f 44 d8 4c 8b 3b <49> 8b 07 49 39 [ 5954.096665] RIP [] __bfs+0xc8/0x260 [ 5954.096665] RSP [ 5954.096665] CR2: 0000000000000000 [ 5954.127991] ---[ end trace 85a6727c2d4e3d90 ]--- Cheers, Dave. -- Dave Chinner david@fromorbit.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/