Yinghai Lu 321bf4ed5f drivers/base/memory.c: fix memory_dev_init() long delay ... One system with 2048g ram, reported soft lockup on recent kernel. [ 34.426749] cpu_dev_init done [ 61.166399] BUG: soft lockup - CPU#0 stuck for 22s! [swapper/0:1] [ 61.166733] Modules linked in: [ 61.166904] irq event stamp: 1935610 [ 61.178431] hardirqs last enabled at (1935609): [<ffffffff81ce8c05>] mutex_lock_nested+0x299/0x2b4 [ 61.178923] hardirqs last disabled at (1935610): [<ffffffff81cf2bab>] apic_timer_interrupt+0x6b/0x80 [ 61.198767] softirqs last enabled at (1935476): [<ffffffff8106e59c>] __do_softirq+0x195/0x1ab [ 61.218604] softirqs last disabled at (1935471): [<ffffffff81cf359c>] call_softirq+0x1c/0x30 [ 61.238408] CPU 0 [ 61.238549] Modules linked in: [ 61.238744] [ 61.238825] Pid: 1, comm: swapper/0 Not tainted 3.3.0-rc1-tip-yh-02076-g962f689-dirty #171 [ 61.278212] RIP: 0010:[<ffffffff810b3e3a>] [<ffffffff810b3e3a>] lock_release+0x90/0x9c [ 61.278627] RSP: 0018:ffff883f64dbfd70 EFLAGS: 00000246 [ 61.298287] RAX: ffff883f64dc0000 RBX: 0000000000000000 RCX: 000000000000008b [ 61.298690] RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 [ 61.318383] RBP: ffff883f64dbfda0 R08: 0000000000000001 R09: 000000000000008b [ 61.338215] R10: 0000000000000000 R11: 0000000000000000 R12: ffff883f64dbfd10 [ 61.338610] R13: ffff883f64dc0708 R14: ffff883f64dc0708 R15: ffffffff81095657 [ 61.358299] FS: 0000000000000000(0000) GS:ffff883f7d600000(0000) knlGS:0000000000000000 [ 61.378118] CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b [ 61.378450] CR2: 0000000000000000 CR3: 00000000024af000 CR4: 00000000000007f0 [ 61.398144] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 [ 61.417918] DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400 [ 61.418260] Process swapper/0 (pid: 1, threadinfo ffff883f64dbe000, task ffff883f64dc0000) [ 61.445358] Stack: [ 61.445511] 0000000000000002 ffff897f649ba168 ffff883f64dbfe10 ffff88ff64bb57a8 [ 61.458040] 0000000000000000 0000000000000000 ffff883f64dbfdc0 ffffffff81ceb1b4 [ 61.458491] 000000000011608c ffff88ff64bb58a8 ffff883f64dbfdf0 ffffffff81c57638 [ 61.478215] Call Trace: [ 61.478367] [<ffffffff81ceb1b4>] _raw_spin_unlock+0x21/0x2e [ 61.497994] [<ffffffff81c57638>] klist_next+0x9e/0xbc [ 61.498264] [<ffffffff8148ba99>] next_device+0xe/0x1e [ 61.517867] [<ffffffff8148c0cc>] subsys_find_device_by_id+0xb7/0xd6 [ 61.518197] [<ffffffff81498846>] find_memory_block_hinted+0x3d/0x66 [ 61.537927] [<ffffffff8149887f>] find_memory_block+0x10/0x12 [ 61.538193] [<ffffffff814988b6>] add_memory_section+0x35/0x9e [ 61.557932] [<ffffffff827fecef>] memory_dev_init+0x68/0xda [ 61.558227] [<ffffffff827fec01>] driver_init+0x97/0xa7 [ 61.577853] [<ffffffff827cdf3c>] kernel_init+0xf6/0x1c0 [ 61.578140] [<ffffffff81cf34a4>] kernel_thread_helper+0x4/0x10 [ 61.597850] [<ffffffff81ceb59d>] ? retint_restore_args+0xe/0xe [ 61.598144] [<ffffffff827cde46>] ? start_kernel+0x3ab/0x3ab [ 61.617826] [<ffffffff81cf34a0>] ? gs_change+0xb/0xb [ 61.618060] Code: 10 48 83 3b 00 eb e8 4c 89 f2 44 89 fe 4c 89 ef e8 e1 fe ff ff 65 48 8b 04 25 40 bc 00 00 c7 80 cc 06 00 00 00 00 00 00 41 54 9d <5e> 5b 41 5c 41 5d 41 5e 41 5f 5d c3 55 48 89 e5 41 57 41 89 cf [ 89.285380] memory_dev_init done Finally it takes about 55s to create 16400 memory entries. Root cause: for x86_64, 2048g (with 2g hole at [2g,4g), and TOP2 will be 2050g), will have 16400 memory block. find_memory_block/subsys_find_device_by_id will be expensive with that many entries. Actually, we don't need to find that memory block for BOOT path. Skip that finding make it get back to normal. [ 34.466696] cpu_dev_init done [ 35.290080] memory_dev_init done Also solved the delay with topology_init when sections_per_block is not 1. Signed-off-by: Yinghai Lu <yinghai@kernel.org> Cc: Kay Sievers <kay.sievers@vrfy.org> Cc: Nathan Fontenot <nfont@austin.ibm.com> Cc: Robin Holt <holt@sgi.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2012-02-02 15:50:05 -08:00
..
power	PM / Domains: Skip governor functions for CONFIG_PM_RUNTIME unset	2012-01-14 00:39:36 +01:00
regmap	regmap: Reset cache status when reinitialsing the cache	2012-01-20 13:49:30 +00:00
attribute_container.c
base.h	cpu: Do not return errors from cpu_dev_init() which will be ignored	2012-01-11 15:49:43 -08:00
bus.c	kernel-doc: fix new warnings in driver-core	2012-01-24 10:47:41 -08:00
class.c
core.c	base/core.c:fix typo in comment in function device_add	2012-01-24 10:47:42 -08:00
cpu.c	driver core: cpu: remove kernel warning when removing a cpu	2012-02-02 10:43:16 -08:00
dd.c
devres.c
devtmpfs.c	Merge branch 'for-linus2' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs	2012-01-08 12:19:57 -08:00
dma-buf.c	dma-buf: Introduce dma buffer sharing mechanism	2012-01-06 10:20:21 +00:00
dma-coherent.c
dma-mapping.c
driver.c
firmware_class.c	PM / Sleep: Fix read_unlock_usermodehelper() call.	2012-01-23 21:59:08 +01:00
firmware.c
hypervisor.c
init.c
isa.c
Kconfig	dma-buf: drop option text so users don't select it.	2012-01-13 09:05:14 +00:00
Makefile	driver core: remove drivers/base/sys.c and include/linux/sysdev.h	2012-01-22 14:31:15 -07:00
map.c
memory.c	drivers/base/memory.c: fix memory_dev_init() long delay	2012-02-02 15:50:05 -08:00
module.c
node.c	drivers/base/memory.c: fix memory_dev_init() long delay	2012-02-02 15:50:05 -08:00
platform.c	Merge branch 'pm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm	2012-01-08 13:10:57 -08:00
syscore.c
topology.c	cpu: convert 'cpu' and 'machinecheck' sysdev_class to a regular subsystem	2011-12-21 14:29:42 -08:00
transport_class.c