01 May, 2013
33 commits
-
One of the problems that arise when converting dedicated custom threadpool
to workqueue is that the shared worker pool used by workqueue anonimizes
each worker making it more difficult to identify what the worker was doing
on which target from the output of sysrq-t or debug dump from oops, BUG()
and friends.For example, after writeback is converted to use workqueue instead of
priviate thread pool, there's no easy to tell which backing device a
writeback work item was working on at the time of task dump, which,
according to our writeback brethren, is important in tracking down issues
with a lot of mounted file systems on a lot of different devices.This patchset implements a way for a work function to mark its execution
instance so that task dump of the worker task includes information to
indicate what the work item was doing.An example WARN dump would look like the following.
WARNING: at fs/fs-writeback.c:1015 bdi_writeback_workfn+0x2b4/0x3c0()
Modules linked in:
CPU: 0 Pid: 28 Comm: kworker/u18:0 Not tainted 3.9.0-rc1-work+ #24
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
Workqueue: writeback bdi_writeback_workfn (flush-8:16)
ffffffff820a3a98 ffff88015b927cb8 ffffffff81c61855 ffff88015b927cf8
ffffffff8108f500 0000000000000000 ffff88007a171948 ffff88007a1716b0
ffff88015b49df00 ffff88015b8d3940 0000000000000000 ffff88015b927d08
Call Trace:
[] dump_stack+0x19/0x1b
[] warn_slowpath_common+0x70/0xa0
...This patch:
Implement probe_kthread_data() which returns kthread_data if accessible.
The function is equivalent to kthread_data() except that the specified
@task may not be a kthread or its vfork_done is already cleared rendering
struct kthread inaccessible. In the former case, probe_kthread_data() may
return any value. In the latter, NULL.This will be used to safely print debug information without affecting
synchronization in the normal paths. Workqueue debug info printing on
dump_stack() and friends will make use of it.Signed-off-by: Tejun Heo
Cc: Oleg Nesterov
Acked-by: Jan Kara
Cc: Dave Chinner
Cc: Ingo Molnar
Cc: Jens Axboe
Cc: Peter Zijlstra
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
After the recent generic debug info on dump_stack() and friends, arc
is printing duplicate information on debug dumps.[ARCLinux]$ ./crash
crash/50: potentially unexpected fatal signal 11.
Signed-off-by: Tejun Heo
Cc: Bjorn Helgaas
Cc: David S. Miller
Cc: Fengguang Wu
Cc: Heiko Carstens
Cc: Jesper Nilsson
Cc: Martin Schwidefsky
Cc: Mike Frysinger
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
show_regs() is inherently arch-dependent but it does make sense to print
generic debug information and some archs already do albeit in slightly
different forms. This patch introduces a generic function to print debug
information from show_regs() so that different archs print out the same
information and it's much easier to modify what's printed.show_regs_print_info() prints out the same debug info as dump_stack()
does plus task and thread_info pointers.* Archs which didn't print debug info now do.
alpha, arc, blackfin, c6x, cris, frv, h8300, hexagon, ia64, m32r,
metag, microblaze, mn10300, openrisc, parisc, score, sh64, sparc,
um, xtensa* Already prints debug info. Replaced with show_regs_print_info().
The printed information is superset of what used to be there.arm, arm64, avr32, mips, powerpc, sh32, tile, unicore32, x86
* s390 is special in that it used to print arch-specific information
along with generic debug info. Heiko and Martin think that the
arch-specific extra isn't worth keeping s390 specfic implementation.
Converted to use the generic version.Note that now all archs print the debug info before actual register
dumps.An example BUG() dump follows.
kernel BUG at /work/os/work/kernel/workqueue.c:4841!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
RIP: 0010:[] [] init_workqueues+0x4/0x6
RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246
RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
Call Trace:
[] do_one_initcall+0x122/0x170
[] kernel_init_freeable+0x9b/0x1c8
[] ? rest_init+0x140/0x140
[] kernel_init+0xe/0xf0
[] ret_from_fork+0x7c/0xb0
[] ? rest_init+0x140/0x140
...v2: Typo fix in x86-32.
v3: CPU number dropped from show_regs_print_info() as
dump_stack_print_info() has been updated to print it. s390
specific implementation dropped as requested by s390 maintainers.Signed-off-by: Tejun Heo
Acked-by: David S. Miller
Acked-by: Jesper Nilsson
Cc: Heiko Carstens
Cc: Martin Schwidefsky
Cc: Bjorn Helgaas
Cc: Fengguang Wu
Cc: Mike Frysinger
Cc: Vineet Gupta
Cc: Sam Ravnborg
Acked-by: Chris Metcalf [tile bits]
Acked-by: Richard Kuo [hexagon bits]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
x86 and ia64 can acquire extra hardware identification information
from DMI and print it along with task dumps; however, the usage isn't
consistent.* x86 show_regs() collects vendor, product and board strings and print
them out with PID, comm and utsname. Some of the information is
printed again later in the same dump.* warn_slowpath_common() explicitly accesses the DMI board and prints
it out with "Hardware name:" label. This applies to both x86 and
ia64 but is irrelevant on all other archs.* ia64 doesn't show DMI information on other non-WARN dumps.
This patch introduces arch-specific hardware description used by
dump_stack(). It can be set by calling dump_stack_set_arch_desc()
during boot and, if exists, printed out in a separate line with
"Hardware name:" label.dmi_set_dump_stack_arch_desc() is added which sets arch-specific
description from DMI data. It uses dmi_ids_string[] which is set from
dmi_present() used for DMI debug message. It is superset of the
information x86 show_regs() is using. The function is called from x86
and ia64 boot code right after dmi_scan_machine().This makes the explicit DMI handling in warn_slowpath_common()
unnecessary. Removed.show_regs() isn't yet converted to use generic debug information
printing and this patch doesn't remove the duplicate DMI handling in
x86 show_regs(). The next patch will unify show_regs() handling and
remove the duplication.An example WARN dump follows.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #3
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f500 ffffffff82228240 0000000000000040 ffffffff8234a08e
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[] dump_stack+0x19/0x1b
[] warn_slowpath_common+0x70/0xa0
[] warn_slowpath_null+0x1a/0x20
[] init_workqueues+0x35/0x505
...v2: Use the same string as the debug message from dmi_present() which
also contains BIOS information. Move hardware name into its own
line as warn_slowpath_common() did. This change was suggested by
Bjorn Helgaas.Signed-off-by: Tejun Heo
Cc: Bjorn Helgaas
Cc: David S. Miller
Cc: Fengguang Wu
Cc: Heiko Carstens
Cc: Jesper Nilsson
Cc: Martin Schwidefsky
Cc: Mike Frysinger
Cc: Vineet Gupta
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
We're goning to use DMI identification for other purposes too. Morph
dmi_dump_ids() which is used to print DMI identification as a debug
message during boot into dmi_format_ids() which formats the same
information sans the leading "DMI:" tag into a string buffer.dmi_present() is updated to format the information into dmi_ids_string[]
using the new function and print it with "DMI:" prefix.dmi_ids_string[] will be used for another purpose by a future patch.
Signed-off-by: Tejun Heo
Cc: Bjorn Helgaas
Cc: David S. Miller
Cc: Fengguang Wu
Cc: Heiko Carstens
Cc: Jesper Nilsson
Cc: Martin Schwidefsky
Cc: Mike Frysinger
Cc: Vineet Gupta
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Both dump_stack() and show_stack() are currently implemented by each
architecture. show_stack(NULL, NULL) dumps the backtrace for the
current task as does dump_stack(). On some archs, dump_stack() prints
extra information - pid, utsname and so on - in addition to the
backtrace while the two are identical on other archs.The usages in arch-independent code of the two functions indicate
show_stack(NULL, NULL) should print out bare backtrace while
dump_stack() is used for debugging purposes when something went wrong,
so it does make sense to print additional information on the task which
triggered dump_stack().There's no reason to require archs to implement two separate but mostly
identical functions. It leads to unnecessary subtle information.This patch expands the dummy fallback dump_stack() implementation in
lib/dump_stack.c such that it prints out debug information (taken from
x86) and invokes show_stack(NULL, NULL) and drops arch-specific
dump_stack() implementations in all archs except blackfin. Blackfin's
dump_stack() does something wonky that I don't understand.Debug information can be printed separately by calling
dump_stack_print_info() so that arch-specific dump_stack()
implementation can still emit the same debug information. This is used
in blackfin.This patch brings the following behavior changes.
* On some archs, an extra level in backtrace for show_stack() could be
printed. This is because the top frame was determined in
dump_stack() on those archs while generic dump_stack() can't do that
reliably. It can be compensated by inlining dump_stack() but not
sure whether that'd be necessary.* Most archs didn't use to print debug info on dump_stack(). They do
now.An example WARN dump follows.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Hardware name: empty
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #9
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f50f ffffffff82228240 0000000000000040 ffffffff8234a03c
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[] dump_stack+0x19/0x1b
[] warn_slowpath_common+0x7f/0xc0
[] warn_slowpath_null+0x1a/0x20
[] init_workqueues+0x35/0x505
...v2: CPU number added to the generic debug info as requested by s390
folks and dropped the s390 specific dump_stack(). This loses %ksp
from the debug message which the maintainers think isn't important
enough to keep the s390-specific dump_stack() implementation.dump_stack_print_info() is moved to kernel/printk.c from
lib/dump_stack.c. Because linkage is per objecct file,
dump_stack_print_info() living in the same lib file as generic
dump_stack() means that archs which implement custom dump_stack()
- at this point, only blackfin - can't use dump_stack_print_info()
as that will bring in the generic version of dump_stack() too. v1
The v1 patch broke build on blackfin due to this issue. The build
breakage was reported by Fengguang Wu.Signed-off-by: Tejun Heo
Acked-by: David S. Miller
Acked-by: Vineet Gupta
Acked-by: Jesper Nilsson
Acked-by: Vineet Gupta
Acked-by: Martin Schwidefsky [s390 bits]
Cc: Heiko Carstens
Cc: Mike Frysinger
Cc: Fengguang Wu
Cc: Bjorn Helgaas
Cc: Sam Ravnborg
Acked-by: Richard Kuo [hexagon bits]
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
show_stack(current or NULL, NULL) is used by arch-independent code to dump
backtrace of the current task; however, sparc32 show_stack() doesn't
implement it and wouldn't print any backtrace when NULL @_ksp is specfied.Make show_stack() acquire and use %fp if @tsk is NULL or current and @_ksp
is NULL. This makes %fp fetching in dump_stack() unnecessary. Make it
use NULL for @_ksp instead.Only compile tested.
Signed-off-by: Tejun Heo
Acked-by: David S. Miller
Cc: Bjorn Helgaas
Cc: Fengguang Wu
Cc: Heiko Carstens
Cc: Jesper Nilsson
Cc: Martin Schwidefsky
Cc: Mike Frysinger
Cc: Vineet Gupta
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
There are multiple ways a task can be dumped - explicit call to
dump_stack(), triggering WARN() or BUG(), through sysrq-t and so on.
Most of what gets printed is upto each architecture and the current
state is not particularly pretty. Different pieces of information are
presented differently depending on which path the dump takes and which
architecture it's running on. This is messy for no good reason and
makes it exceedingly difficult to add or modify debug information to
task dumps.In all archs except for s390, there's nothing arch-specific about the
printed debug information. This patchset updates all those archs to use
the same helpers to consistently print out the same debug information.An example WARN dump after this patchset.
WARNING: at kernel/workqueue.c:4841 init_workqueues+0x35/0x505()
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #3
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
0000000000000009 ffff88007c861e08 ffffffff81c614dc ffff88007c861e48
ffffffff8108f500 ffffffff82228240 0000000000000040 ffffffff8234a08e
0000000000000000 0000000000000000 0000000000000000 ffff88007c861e58
Call Trace:
[] dump_stack+0x19/0x1b
[] warn_slowpath_common+0x70/0xa0
[] warn_slowpath_null+0x1a/0x20
[] init_workqueues+0x35/0x505
...And BUG dump.
kernel BUG at kernel/workqueue.c:4841!
invalid opcode: 0000 [#1] PREEMPT SMP DEBUG_PAGEALLOC
Modules linked in:
CPU: 0 PID: 1 Comm: swapper/0 Not tainted 3.9.0-rc1-work+ #7
Hardware name: empty empty/S3992, BIOS 080011 10/26/2007
task: ffff88007c85e040 ti: ffff88007c860000 task.ti: ffff88007c860000
RIP: 0010:[] [] init_workqueues+0x4/0x6
RSP: 0000:ffff88007c861ec8 EFLAGS: 00010246
RAX: ffff88007c861fd8 RBX: ffffffff824466a8 RCX: 0000000000000001
RDX: 0000000000000046 RSI: 0000000000000001 RDI: ffffffff8234a07a
RBP: ffff88007c861ec8 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000001 R11: 0000000000000000 R12: ffffffff8234a07a
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
FS: 0000000000000000(0000) GS:ffff88007dc00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 000000008005003b
CR2: ffff88015f7ff000 CR3: 00000000021f1000 CR4: 00000000000007f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000ffff0ff0 DR7: 0000000000000400
Stack:
ffff88007c861ef8 ffffffff81000312 ffffffff824466a8 ffff88007c85e650
0000000000000003 0000000000000000 ffff88007c861f38 ffffffff82335e5d
ffff88007c862080 ffffffff8223d8c0 ffff88007c862080 ffffffff81c47760
Call Trace:
[] do_one_initcall+0x122/0x170
[] kernel_init_freeable+0x9b/0x1c8
[] ? rest_init+0x140/0x140
[] kernel_init+0xe/0xf0
[] ret_from_fork+0x7c/0xb0
[] ? rest_init+0x140/0x140
...This patchset contains the following seven patches.
0001-x86-don-t-show-trace-beyond-show_stack-NULL-NULL.patch
0002-sparc32-make-show_stack-acquire-fp-if-_ksp-is-not-sp.patch
0003-dump_stack-consolidate-dump_stack-implementations-an.patch
0004-dmi-morph-dmi_dump_ids-into-dmi_format_ids-which-for.patch
0005-dump_stack-implement-arch-specific-hardware-descript.patch
0006-dump_stack-unify-debug-information-printed-by-show_r.patch
0007-arc-print-fatal-signals-reduce-duplicated-informatio.patch0001-0002 update stack dumping functions in x86 and sparc32 in
preparation.0003 makes all arches except blackfin use generic dump_stack().
blackfin still uses the generic helper to print the same info.0004-0005 properly abstract DMI identifier printing in WARN() and
show_regs() so that all dumps print out the information. This enables
show_regs() to use the same debug info message.0006 updates show_regs() of all arches to use a common generic helper
to print debug info.0007 removes somem duplicate information from arc dumps.
While this patchset changes how debug info is printed on some archs,
the printed information is always superset of what used to be there.This patchset makes task dump debug messages consistent and enables
adding more information. Workqueue is scheduled to add worker
information including the workqueue in use and work item specific
description.While this patch touches a lot of archs, it isn't too likely to cause
non-trivial conflicts with arch-specfic changes and would probably be
best to route together either through -mm.x86 is tested but other archs are either only compile tested or not
tested at all. Changes to most archs are generally trivial.This patch:
show_stack(current or NULL, NULL) is used to print the backtrace of the
current task. As trace beyond the function itself isn't of much
interest to anyone, don't show it by determining sp and bp in
show_stack()'s frame and passing them to show_stack_log_lvl().This brings show_stack(NULL, NULL)'s behavior in line with
dump_stack().Signed-off-by: Tejun Heo
Cc: Bjorn Helgaas
Cc: David S. Miller
Cc: Fengguang Wu
Cc: Heiko Carstens
Cc: Jesper Nilsson
Cc: Martin Schwidefsky
Cc: Mike Frysinger
Cc: Vineet Gupta
Cc: Sam Ravnborg
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Also replace deprecated printk(KERN_ERR...) with pr_err() as suggested
by Yinghai, attaching the function name to provide plenty info.Signed-off-by: Lin Feng
Cc: Yinghai Lu
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
It creates a mapping of 3 pages and checks that reads, writes and
clear-refs result in present and soft-dirt bits reported from pagemap2
set as expected.[akpm@linux-foundation.org: alphasort the Makefile TARGETS to reduce rejects]
Signed-off-by: Pavel Emelyanov
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Allow zcache to be built/loaded as a module. Note runtime dependency
disallows loading if cleancache/frontswap lazy initialization patches
are not present. Zsmalloc support has not yet been merged into zcache
but, once merged, could now easily be selected via a module_param.If built-in (not built as a module), the original mechanism of enabling
via a kernel boot parameter is retained, but this should be considered
deprecated.Note that module unload is explicitly not yet supported.
Signed-off-by: Dan Magenheimer
[v1: Rebased with different order of patches]
[v2: Removed [CLEANCACHE|FRONTSWAP]_HAS_LAZY_INIT ifdef]
[v3: Rebased on top of ramster->zcache move]
[v4: Redid the Makefile]
[v5: s/ZCACHE2/ZCACHE/]
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Florian Schmaus
Cc: Minchan Kim
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Enable module support for ramster. Note runtime dependency disallows
loading if cleancache/frontswap lazy initialization patches are not
present.If built-in (not built as a module), the original mechanism of enabling
via a kernel boot parameter is retained, but this should be considered
deprecated.Note that module unload is explicitly not yet supported.
[v1: Fixed compile issues since ramster_init now has four arguments]
[v2: Fixed rebase on ramster->zcache move]
[akpm@linux-foundation.org: use_frontswap_selfshrink cannot be __initdata]
Signed-off-by: Dan Magenheimer
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Florian Schmaus
Cc: Minchan Kim
Cc: Stefan Hengelein
Cc: Wu Fengguang
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
In the past it either used to be NULL or the "older" backend. Now we
also return -Exx error codes.Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Dan Magenheimer
Cc: Florian Schmaus
Cc: Minchan Kim
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Allow Xen tmem shim to be built/loaded as a module. Xen self-ballooning
and frontswap-selfshrinking are now also "lazily" initialized when the
Xen tmem shim is loaded as a module, unless explicitly disabled by
module parameters.Note runtime dependency disallows loading if cleancache/frontswap lazy
initialization patches are not present.If built-in (not built as a module), the original mechanism of enabling
via a kernel boot parameter is retained, but this should be considered
deprecated.Note that module unload is explicitly not yet supported.
[v1: Removed the [CLEANCACHE|FRONTSWAP]_HAS_LAZY_INIT ifdef]
[v2: Squashed the xen/tmem: Remove the subsys call patch in]
[akpm@linux-foundation.org: fix build (disable_frontswap_selfshrinking undeclared)]
Signed-off-by: Dan Magenheimer
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Florian Schmaus
Cc: Minchan Kim
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
cleancache_ops is used to decide whether backend is registered.
So now cleancache_enabled is always true if defined CONFIG_CLEANCACHE.Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Dan Magenheimer
Cc: Florian Schmaus
Cc: Konrad Rzeszutek Wilk
Cc: Minchan Kim
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Instead of using a backend_registered to determine whether a backend is
enabled. This allows us to remove the backend_register check and just
do 'if (cleancache_ops)'[v1: Rebase on top of b97c4b430b0a (ramster->zcache move]
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Dan Magenheimer
Cc: Florian Schmaus
Cc: Minchan Kim
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
With the goal of allowing tmem backends (zcache, ramster, Xen tmem) to
be built/loaded as modules rather than built-in and enabled by a boot
parameter, this patch provides "lazy initialization", allowing backends
to register to cleancache even after filesystems were mounted. Calls to
init_fs and init_shared_fs are remembered as fake poolids but no real
tmem_pools created. On backend registration the fake poolids are mapped
to real poolids and respective tmem_pools.Signed-off-by: Stefan Hengelein
Signed-off-by: Florian Schmaus
Signed-off-by: Andor Daam
Signed-off-by: Dan Magenheimer
[v1: Minor fixes: used #define for some values and bools]
[v2: Removed CLEANCACHE_HAS_LAZY_INIT]
[v3: Added more comments, added a lock for [shared_|]fs_poolid_map]
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Frontswap initialization routine depends on swap_lock, which want to be
atomic about frontswap's first appearance. IOW, frontswap is not present
and will fail all calls OR frontswap is fully functional but if new
swap_info_struct isn't registered by enable_swap_info, swap subsystem
doesn't start I/O so there is no race between init procedure and page I/O
working on frontswap.So let's remove unnecessary swap_lock dependency.
Cc: Dan Magenheimer
Signed-off-by: Minchan Kim
[v1: Rebased on my branch, reworked to work with backends loading late]
[v2: Added a check for !map]
[v3: Made the invalidate path follow the init path]
[v4: Address comments by Wanpeng Li ]
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Florian Schmaus
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
After allowing tmem backends to build/run as modules, frontswap_enabled
always true if defined CONFIG_FRONTSWAP. But frontswap_test() depends on
whether backend is registered, mv it into frontswap.c using fronstswap_ops
to make the decision.frontswap_set/clear are not used outside frontswap, so don't export them.
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Dan Magenheimer
Cc: Florian Schmaus
Cc: Konrad Rzeszutek Wilk
Cc: Minchan Kim
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
This simplifies the code in the frontswap - we can get rid of the
'backend_registered' test and instead check against frontswap_ops.[v1: Rebase on top of 703ba7fe5e0 (ramster->zcache move]
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Andor Daam
Cc: Dan Magenheimer
Cc: Florian Schmaus
Cc: Minchan Kim
Cc: Stefan Hengelein
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
With the goal of allowing tmem backends (zcache, ramster, Xen tmem) to
be built/loaded as modules rather than built-in and enabled by a boot
parameter, this patch provides "lazy initialization", allowing backends
to register to frontswap even after swapon was run. Before a backend
registers all calls to init are recorded and the creation of tmem_pools
delayed until a backend registers or until a frontswap store is
attempted.Signed-off-by: Stefan Hengelein
Signed-off-by: Florian Schmaus
Signed-off-by: Andor Daam
Signed-off-by: Dan Magenheimer
[v1: Fixes per Seth Jennings suggestions]
[v2: Removed FRONTSWAP_HAS_.. ]
[v3: Fix up per Bob Liu recommendations]
[v4: Fix up per Andrew's comments]
Signed-off-by: Konrad Rzeszutek Wilk
Signed-off-by: Bob Liu
Cc: Wanpeng Li
Cc: Dan Magenheimer
Cc: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Call cond_resched() in shrink_dcache_parent() to maintain interactivity.
Before this patch:
void shrink_dcache_parent(struct dentry * parent)
{
while ((found = select_parent(parent, &dispose)) != 0)
shrink_dentry_list(&dispose);
}select_parent() populates the dispose list with dentries which
shrink_dentry_list() then deletes. select_parent() carefully uses
need_resched() to avoid doing too much work at once. But neither
shrink_dcache_parent() nor its called functions call cond_resched(). So
once need_resched() is set select_parent() will return single dentry
dispose list which is then deleted by shrink_dentry_list(). This is
inefficient when there are a lot of dentry to process. This can cause
softlockup and hurts interactivity on non preemptable kernels.This change adds cond_resched() in shrink_dcache_parent(). The benefit
of this is that need_resched() is quickly cleared so that future calls
to select_parent() are able to efficiently return a big batch of dentry.These additional cond_resched() do not seem to impact performance, at
least for the workload below.Here is a program which can cause soft lockup if other system activity
sets need_resched().int main()
{
struct rlimit rlim;
int i;
int f[100000];
char buf[20];
struct timeval t1, t2;
double diff;/* cleanup past run */
system("rm -rf x");/* boost nfile rlimit */
rlim.rlim_cur = 200000;
rlim.rlim_max = 200000;
if (setrlimit(RLIMIT_NOFILE, &rlim))
err(1, "setrlimit");/* make directory for files */
if (mkdir("x", 0700))
err(1, "mkdir");if (gettimeofday(&t1, NULL))
err(1, "gettimeofday");/* populate directory with open files */
for (i = 0; i < 100000; i++) {
snprintf(buf, sizeof(buf), "x/%d", i);
f[i] = open(buf, O_CREAT);
if (f[i] == -1)
err(1, "open");
}/* close some of the files */
for (i = 0; i < 85000; i++)
close(f[i]);/* unlink all files, even open ones */
system("rm -rf x");if (gettimeofday(&t2, NULL))
err(1, "gettimeofday");diff = (((double)t2.tv_sec * 1000000 + t2.tv_usec) -
((double)t1.tv_sec * 1000000 + t1.tv_usec));printf("done: %g elapsed\n", diff/1e6);
return 0;
}Signed-off-by: Greg Thelen
Signed-off-by: Dave Chinner
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Its only caller evict() has promised a non-NULL inode->i_bdev.
Signed-off-by: Yan Hong
Cc: Al Viro
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
When we run the crackerjack testsuite, the inotify_add_watch test is
stalled.This is caused by the invalid mask 0 - the task is waiting for the event
but it never comes. inotify_add_watch() should return -EINVAL as it did
before commit 676a0675cf92 ("inotify: remove broken mask checks causing
unmount to be EINVAL"). That commit removes the invalid mask check, but
that check is needed.Check the mask's ALL_INOTIFY_BITS before the inotify_arg_to_mask() call.
If none are set, just return -EINVAL.Because IN_UNMOUNT is in ALL_INOTIFY_BITS, this change will not trigger
the problem that above commit fixed.[akpm@linux-foundation.org: fix build]
Signed-off-by: Zhao Hongjiang
Acked-by: Jim Somerville
Cc: Paul Gortmaker
Cc: Jerome Marchand
Cc: Eric Paris
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix the following compilation warnings:
mm/slab.c: In function `kmem_cache_init_late':
mm/slab.c:1778:2: warning: statement with no effect [-Wunused-value]mm/page_cgroup.c: In function `page_cgroup_init':
mm/page_cgroup.c:305:2: warning: statement with no effect [-Wunused-value]Signed-off-by: Vincent Stehlé
Cc: David Rientjes
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Remove unused local `us', which broke the build. Also nuke an unneeded
cast.Repairs commit 191648d03d20 ("usb: storage: Convert US_DEBUGP to
usb_stor_dbg").Cc: Joe Perches
Acked-by: David Rientjes
Cc: Greg KH
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Pull arm64 update from Catalin Marinas:
"Main features:- Versatile Express SoC (model) support - DT files and Kconfig
entries (there are no arch/arm64/mach-* directories). The bulk of
the code has already been moved to drivers/ as part of the ARM SoC
clean-up.- Basic multi-cluster support (CPU logical map initialised from the
DT)- Simple earlyprintk support for UART 8250/16550 and FastModel
console output- Optimised kernel library bitops and string functions.
- Automatic initialisation of the irqchip and clocks via DT"
* tag 'arm64-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cmarinas/linux-aarch64: (26 commits)
arm64: Use acquire/release semantics instead of explicit DMB
arm64: klib: bitops: fix unpredictable stxr usage
arm64: vexpress: Enable ARMv8 RTSM model (SoC) support
arm64: vexpress: Add dts files for the ARMv8 RTSM models
arm64: Survive invalid cpu enable-methods
arm64: mm: Correct show_pte behaviour
arm64: Fix compat types affecting struct compat_stat
arm64: Execute DSB during thread switching for TLB/cache maintenance
arm64: compiling issue, need add include/asm/vga.h file
arm64: smp: honour #address-size when parsing CPU reg property
arm64: Define cmpxchg64 and cmpxchg64_local for outside use
arm64: Define readq and writeq for driver module using
arm64: Fix task tracing
arm64: add explicit symbols to ESR_EL1 decoding
arm64: Use irqchip_init() for interrupt controller initialisation
arm64: psci: Use the MPIDR values from cpu_logical_map for cpu ids.
arm64: klib: Optimised atomic bitops
arm64: klib: Optimised string functions
arm64: klib: Optimised memory functions
arm64: head: match all affinity levels in the pen of the secondaries
... -
Pull arch/metag update from James Hogan:
- Various fixes for the interrupting perf counter handling in metag's
perf backend.- Add OProfile support based on perf.
- Sets up cache partitions for SMP so bootloader doesn't have to.
- Patch from Paul Bolle to remove ARCH_POPULATES_NODE_MAP again
(touches microblaze too).- Add TLS pointer regset to metag ptrace api.
- Add exported metag DSP extended context handling header .
- Increase defconfig log buffer size to 128KiB.
- Various fixes, typos, missing exports.
* tag 'metag-for-v3.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/jhogan/metag:
metag: defconfigs: increase log buffer 8KiB => 128KiB
metag: avoid unnecessary builtin dtb rebuilds
metag: add exported for extended context handling
metag: export _metag_da_present and cpu_2_hwthread_id
metag: ptrace: Implement NT_METAG_TLS
memblock: Kill ARCH_POPULATES_NODE_MAP once more
metag: cachepart: fix get_global_dcache_size() typo
metag: cachepart: take into account small cache bits
metag: smp: copy cache partition and enable GCOn
metag: OProfile support
metag: perf: prepare for use by oprofile
metag: perf: don't reset TXTACTCYC
metag: perf: use hard_processor_id() to get thread
metag: perf: fix frequency sampling (dynamic period)
metag: perf: add missing prev_count updates
metag: perf: fixes for interrupting perf counters
metag: perf: fix wrap handling in delta calculation
metag: perf: fix core internal / perf channel mux -
Pull m68k update from Geert Uytterhoeven.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/geert/linux-m68k:
m68k: Remove inline strlen() implementation
m68k/atari: USB - add platform devices for EtherNAT/NetUSBee ISP1160 HCD
m68k: Implement ndelay() based on the existing udelay() logic
m68k/atari: EtherNAT - add interrupt chip definition for CPLD interrupts
m68k/atari: EtherNEC - add platform device support
m68k/atari: EtherNAT - platform device and IRQ support code
m68k/atari: use dedicated irq_chip for timer D interrupts
m68k/atari: ROM port ISA adapter support
m68k: Add missing cmpxchg64() if CONFIG_RMW_INSNS=y -
Pull edac fixes from Mauro Carvalho Chehab:
"Two edac fixes:- i7300_edac currently reports a wrong number of DIMMs when the
memory controller is in single channel mode- on some Sandy Bridge machines, the EDAC driver bails out as one of
the PCI IDs used by the driver is hidden by BIOS. As the driver
uses it only to detect the type of memory, make it optional at the
driver"* 'linux_next' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-edac:
edac: sb_edac.c should not require prescence of IMC_DDRIO device
i7300_edac: Fix memory detection in single mode -
Pull media update from Mauro Carvalho Chehab:
- OF documentation and patches at core and drivers, to be used by for
embedded media systems- some I2C drivers used on go7007 were rewritten/promoted from staging:
sony-btf-mpx, tw2804, tw9903, tw9906, wis-ov7640, wis-uda1342- add fimc-is driver (Exynos)
- add a new radio driver: radio-si476x
- add a two new tuners: r820t and tuner_it913x
- split camera code on em28xx driver and add more models
- the cypress firmware load is used outside dvb usb drivers. So, move
it to a common directory to make easier to re-use it- siano media driver updated to work with sms2270 devices
- several work done in order to promote go7007 and solo6x1x out of
staging (still, there are some pending issues)- several API compliance fixes at v4l2 drivers that don't behave as
expected- as usual, lots of driver fixes, improvements, cleanups and new device
addition at the existing drivers.* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media: (831 commits)
[media] cx88: make core less verbose
[media] em28xx: fix oops at em28xx_dvb_bus_ctrl()
[media] s5c73m3: fix indentation of the help section in Kconfig
[media] cx25821-alsa: get rid of a __must_check warning
[media] cx25821-video: declare cx25821_vidioc_s_std as static
[media] cx25821-video: remove maxw from cx25821_vidioc_try_fmt_vid_cap
[media] r820t: Remove a warning for an unused value
[media] dib0090: Fix a warning at dib0090_set_EFUSE
[media] dib8000: fix a warning
[media] dib8000: Fix sub-channel range
[media] dib8000: store dtv_property_cache in a temp var
[media] dib8000: warning fix: declare internal functions as static
[media] r820t: quiet gcc warning on n_ring
[media] r820t: memory leak in release()
[media] r820t: precendence bug in r820t_xtal_check()
[media] videodev2.h: Remove the unused old V4L1 buffer types
[media] anysee: Grammar s/report the/report to/
[media] anysee: Initialize ret = 0 in anysee_frontend_attach()
[media] media: videobuf2: fix the length check for mmap
[media] em28xx: save isoc endpoint number for DVB only if endpoint has alt settings with xMaxPacketSize != 0
... -
Pull HID updates from Jiri Kosina:
- hid driver transport cleanup, finalizing the long-desired decoupling
of core from transport layers, by Benjamin Tissoires and Henrik
Rydberg- support for hybrid finger/pen multitouch HID devices, by Benjamin
Tissoires- fix for long-standing issue in Logitech unifying driver sometimes not
inializing properly due to device specifics, by Andrew de los Reyes- Wii remote driver updates to support 2nd generation of devices, by
David Herrmann- support for Apple IR remote
- roccat driver now supports new devices (Roccat Kone Pure, IskuFX), by
Stefan Achatz- debugfs locking fixes in hid debug interface, by Jiri Kosina
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/hid: (43 commits)
HID: protect hid_debug_list
HID: debug: break out hid_dump_report() into hid-debug
HID: Add PID for Japanese version of NE4K keyboard
HID: hid-lg4ff add support for new version of DFGT wheel
HID: icade: u16 which never < 0
HID: clarify Magic Mouse Kconfig description
HID: appleir: add support for Apple ir devices
HID: roccat: added media key support for Kone
HID: hid-lenovo-tpkbd: remove doubled hid_get_drvdata
HID: i2c-hid: fix length for set/get report in i2c hid
HID: wiimote: parse reduced status reports
HID: wiimote: add 2nd generation Wii Remote IDs
HID: wiimote: use unique battery names
HID: hidraw: warn if userspace headers are outdated
HID: multitouch: force BTN_STYLUS for pen devices
HID: multitouch: append " Pen" to the name of the stylus input
HID: multitouch: add handling for pen in dual-sensors device
HID: multitouch: change touch sensor detection in mt_input_configured()
HID: multitouch: do not map usage from non used reports
HID: multitouch: breaks out touch handling in specific functions
... -
Pull trivial tree updates from Jiri Kosina:
"Usual stuff, mostly comment fixes, typo fixes, printk fixes and small
code cleanups"* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial: (45 commits)
mm: Convert print_symbol to %pSR
gfs2: Convert print_symbol to %pSR
m32r: Convert print_symbol to %pSR
iostats.txt: add easy-to-find description for field 6
x86 cmpxchg.h: fix wrong comment
treewide: Fix typo in printk and comments
doc: devicetree: Fix various typos
docbook: fix 8250 naming in device-drivers
pata_pdc2027x: Fix compiler warning
treewide: Fix typo in printks
mei: Fix comments in drivers/misc/mei
treewide: Fix typos in kernel messages
pm44xx: Fix comment for "CONFIG_CPU_IDLE"
doc: Fix typo "CONFIG_CGROUP_CGROUP_MEMCG_SWAP"
mmzone: correct "pags" to "pages" in comment.
kernel-parameters: remove outdated 'noresidual' parameter
Remove spurious _H suffixes from ifdef comments
sound: Remove stray pluses from Kconfig file
radio-shark: Fix printk "CONFIG_LED_CLASS"
doc: put proper reference to CONFIG_MODULE_SIG_ENFORCE
...
30 Apr, 2013
7 commits
-
Pull x86 RAS changes from Ingo Molnar:
- Add an Intel CMCI hotplug fix
- Add AMD family 16h EDAC support
- Make the AMD MCE banks code more flexible for virtual environments
* 'x86-ras-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
amd64_edac: Add Family 16h support
x86/mce: Rework cmci_rediscover() to play well with CPU hotplug
x86, MCE, AMD: Use MCG_CAP MSR to find out number of banks on AMD
x86, MCE, AMD: Replace shared_bank array with is_shared_bank() helper -
Pull x86 platform changes from Ingo Molnar:
"Small fixes and cleanups all over the map"* 'x86-platform-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/setup: Drop unneeded include
x86/olpc/xo1/sci: Don't call input_free_device() after input_unregister_device()
x86/platform/intel/mrst: Remove cast for kmalloc() return value
x86/platform/uv: Replace kmalloc() & memset with kzalloc() -
Pull x86 paravirt update from Ingo Molnar:
"Various paravirtualization related changes - the biggest one makes
guest support optional via CONFIG_HYPERVISOR_GUEST"* 'x86-paravirt-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, wakeup, sleep: Use pvops functions for changing GDT entries
x86, xen, gdt: Remove the pvops variant of store_gdt.
x86-32, gdt: Store/load GDT for ACPI S3 or hibernation/resume path is not needed
x86-64, gdt: Store/load GDT for ACPI S3 or hibernate/resume path is not needed.
x86: Make Linux guest support optional
x86, Kconfig: Move PARAVIRT_DEBUG into the paravirt menu -
Pull x86 mm changes from Ingo Molnar:
"Misc smaller changes all over the map"* 'x86-mm-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86/iommu/dmar: Remove warning for HPET scope type
x86/mm/gart: Drop unnecessary check
x86/mm/hotplug: Put kernel_physical_mapping_remove() declaration in CONFIG_MEMORY_HOTREMOVE
x86/mm/fixmap: Remove unused FIX_CYCLONE_TIMER
x86/mm/numa: Simplify some bit mangling
x86/mm: Re-enable DEBUG_TLBFLUSH for X86_32
x86/mm/cpa: Cleanup split_large_page() and its callee
x86: Drop always empty .text..page_aligned section -
Pull perparatory x86 kasrl changes from Ingo Molnar:
"This contains changes from the ongoing KASLR work, by Kees Cook.The main changes are the use of a read-only IDT on x86 (which
decouples the userspace visible virtual IDT address from the physical
address), and a rework of ELF relocation support, in preparation of
random, boot-time kernel image relocation."* 'x86-kaslr-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, relocs: Refactor the relocs tool to merge 32- and 64-bit ELF
x86, relocs: Build separate 32/64-bit tools
x86, relocs: Add 64-bit ELF support to relocs tool
x86, relocs: Consolidate processing logic
x86, relocs: Generalize ELF structure names
x86: Use a read-only IDT alias on all CPUs -
Pull x86 debug update from Ingo Molnar:
"Two small changes: a documentation update and a constification"* 'x86-debug-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, early-printk: Update earlyprintk documentation (and kill x86 copy)
x86: Constify a few items -
Pull x86 cpuid changes from Ingo Molnar:
"The biggest change is x86 CPU bug handling refactoring and cleanups,
by Borislav Petkov"* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
x86, CPU, AMD: Drop useless label
x86, AMD: Correct {rd,wr}msr_amd_safe warnings
x86: Fold-in trivial check_config function
x86, cpu: Convert AMD Erratum 400
x86, cpu: Convert AMD Erratum 383
x86, cpu: Convert Cyrix coma bug detection
x86, cpu: Convert FDIV bug detection
x86, cpu: Convert F00F bug detection
x86, cpu: Expand cpufeature facility to include cpu bugs