If a kernel thread is preempted in single-cpu mode right after the NOP (nop
about to be turned into a lock prefix), then we CPU hotplug a CPU, and then the
thread is scheduled back again, a SMP-unsafe atomic operation will be used on
shared SMP variables, leading to corruption. No corruption would happen in the
reverse case : going from SMP to UP is ok because we split a bit instruction
into tiny pieces, which does not present this condition.
Changing the 0x90 (single-byte nop) currently used into a 0x3E DS segment
override prefix should fix this issue. Since the default of the atomic
instructions is to use the DS segment anyway, it should not affect the
behavior.
The exception to this are references that use ESP/RSP and EBP/RBP as
the base register (they will use the SS segment), however, in Linux
(a) DS == SS at all times, and (b) we do not distinguish between
segment violations reported as #SS as opposed to #GP, so there is no
need to disassemble the instruction to figure out the suitable segment.
This patch assumes that the 0x3E prefix will leave atomic operations as-is (thus
assuming they normally touch data in the DS segment). Since there seem to be no
obvious ill-use of other segment override prefixes for atomic operations, it
should be safe. It can be verified with a quick
grep -r LOCK_PREFIX include/asm-x86/
grep -A 1 -r LOCK_PREFIX arch/x86/
Taken from
This source :
AMD64 Architecture Programmer's Manual Volume 3: General-Purpose and System
Instructions
States
"Instructions that Reference a Non-Stack Segment—If an instruction encoding
references any base register other than rBP or rSP, or if an instruction
contains an immediate offset, the default segment is the data segment (DS).
These instructions can use the segment-override prefix to select one of the
non-default segments, as shown in Table 1-5."
Therefore, forcing the DS segment on the atomic operations, which already use
the DS segment, should not change.
This source :
http://wiki.osdev.org/X86_Instruction_Encoding
States
"In 64-bit the CS, SS, DS and ES segment overrides are ignored."
Confirmed by "AMD 64-Bit Technology" A.7
http://www.amd.com/us-en/assets/content_type/white_papers_and_tech_docs/x86-64_overview.pdf
"In 64-bit mode, the DS, ES, SS and CS segment-override prefixes have no effect.
These four prefixes are no longer treated as segment-override prefixes in the
context of multipleprefix rules. Instead, they are treated as null prefixes."
This patch applies to 2.6.27-rc2, but would also have to be applied to earlier
kernels (2.6.26, 2.6.25, ...).
Performance impact of the fix : tests done on "xaddq" and "xaddl" shows it
actually improves performances on Intel Xeon, AMD64, Pentium M. It does not
change the performance on Pentium II, Pentium 3 and Pentium 4.
Xeon E5405 2.0GHz :
NR_TESTS 10000000
test empty cycles : 162207948
test test 1-byte nop xadd cycles : 170755422
test test DS override prefix xadd cycles : 170000118 *
test test LOCK xadd cycles : 472012134
AMD64 2.0GHz :
NR_TESTS 10000000
test empty cycles : 146674549
test test 1-byte nop xadd cycles : 150273860
test test DS override prefix xadd cycles : 149982382 *
test test LOCK xadd cycles : 270000690
Pentium 4 3.0GHz
NR_TESTS 10000000
test empty cycles : 290001195
test test 1-byte nop xadd cycles : 310000560
test test DS override prefix xadd cycles : 310000575 *
test test LOCK xadd cycles : 1050103740
Pentium M 2.0GHz
NR_TESTS 10000000
test empty cycles : 180000523
test test 1-byte nop xadd cycles : 320000345
test test DS override prefix xadd cycles : 310000374 *
test test LOCK xadd cycles : 480000357
Pentium 3 550MHz
NR_TESTS 10000000
test empty cycles : 510000231
test test 1-byte nop xadd cycles : 620000128
test test DS override prefix xadd cycles : 620000110 *
test test LOCK xadd cycles : 800000088
Pentium II 350MHz
NR_TESTS 10000000
test empty cycles : 200833494
test test 1-byte nop xadd cycles : 340000130
test test DS override prefix xadd cycles : 340000126 *
test test LOCK xadd cycles : 530000078
Speed test modules can be found at
http://ltt.polymtl.ca/svn/trunk/tests/kernel/test-prefix-speed-32.chttp://ltt.polymtl.ca/svn/trunk/tests/kernel/test-prefix-speed.c
Macro-benchmarks
2.0GHz E5405 Core 2 dual Quad-Core Xeon
Summary
* replace smp lock prefixes with DS segment selector prefixes
no lock prefix (s) with lock prefix (s) Speedup
make -j1 kernel/ 33.94 +/- 0.07 34.91 +/- 0.27 2.8 %
hackbench 50 2.99 +/- 0.01 3.74 +/- 0.01 25.1 %
* replace smp lock prefixes with 0x90 nops
no lock prefix (s) with lock prefix (s) Speedup
make -j1 kernel/ 34.16 +/- 0.32 34.91 +/- 0.27 2.2 %
hackbench 50 3.00 +/- 0.01 3.74 +/- 0.01 24.7 %
Detail :
1 CPU, replace smp lock prefixes with DS segment selector prefixes
make -j1 kernel/
real 0m34.067s
user 0m30.630s
sys 0m2.980s
real 0m33.867s
user 0m30.582s
sys 0m3.024s
real 0m33.939s
user 0m30.738s
sys 0m2.876s
real 0m33.913s
user 0m30.806s
sys 0m2.808s
avg : 33.94s
std. dev. : 0.07s
hackbench 50
Time: 2.978
Time: 2.982
Time: 3.010
Time: 2.984
Time: 2.982
avg : 2.99
std. dev. : 0.01
1 CPU, noreplace-smp
make -j1 kernel/
real 0m35.326s
user 0m30.630s
sys 0m3.260s
real 0m34.325s
user 0m30.802s
sys 0m3.084s
real 0m35.568s
user 0m30.722s
sys 0m3.168s
real 0m34.435s
user 0m30.886s
sys 0m2.996s
avg.: 34.91s
std. dev. : 0.27s
hackbench 50
Time: 3.733
Time: 3.750
Time: 3.761
Time: 3.737
Time: 3.741
avg : 3.74
std. dev. : 0.01
1 CPU, replace smp lock prefixes with 0x90 nops
make -j1 kernel/
real 0m34.139s
user 0m30.782s
sys 0m2.820s
real 0m34.010s
user 0m30.630s
sys 0m2.976s
real 0m34.777s
user 0m30.658s
sys 0m2.916s
real 0m33.924s
user 0m30.634s
sys 0m2.924s
real 0m33.962s
user 0m30.774s
sys 0m2.800s
real 0m34.141s
user 0m30.770s
sys 0m2.828s
avg : 34.16
std. dev. : 0.32
hackbench 50
Time: 2.999
Time: 2.994
Time: 3.004
Time: 2.991
Time: 2.988
avg : 3.00
std. dev. : 0.01
I did more runs (20 runs of each) to compare the nop case to the DS
prefix case. Results in seconds. They actually does not seems to show a
significant difference.
NOP
34.155
33.955
34.012
35.299
35.679
34.141
33.995
35.016
34.254
33.957
33.957
34.008
35.013
34.494
33.893
34.295
34.314
34.854
33.991
34.132
DS
34.080
34.304
34.374
35.095
34.291
34.135
33.940
34.208
35.276
34.288
33.861
33.898
34.610
34.709
33.851
34.256
35.161
34.283
33.865
35.078
Used http://www.graphpad.com/quickcalcs/ttest1.cfm?Format=C to do the
T-test (yeah, I'm lazy) :
Group Group One (DS prefix) Group Two (nops)
Mean 34.37815 34.37070
SD 0.46108 0.51905
SEM 0.10310 0.11606
N 20 20
P value and statistical significance:
The two-tailed P value equals 0.9620
By conventional criteria, this difference is considered to be not statistically significant.
Confidence interval:
The mean of Group One minus Group Two equals 0.00745
95% confidence interval of this difference: From -0.30682 to 0.32172
Intermediate values used in calculations:
t = 0.0480
df = 38
standard error of difference = 0.155
So, unless these calculus are completely bogus, the difference between the nop
and the DS case seems not to be statistically significant.
Signed-off-by: Mathieu Desnoyers <mathieu.desnoyers@polymtl.ca>
Acked-by: H. Peter Anvin <hpa@zytor.com>
CC: Linus Torvalds <torvalds@linux-foundation.org>
CC: Jeremy Fitzhardinge <jeremy@goop.org>
CC: Roland McGrath <roland@redhat.com>
CC: Ingo Molnar <mingo@elte.hu>
Cc: Steven Rostedt <rostedt@goodmis.org>
CC: Steven Rostedt <srostedt@redhat.com>
CC: Thomas Gleixner <tglx@linutronix.de>
CC: Peter Zijlstra <peterz@infradead.org>
CC: Andrew Morton <akpm@linux-foundation.org>
CC: David Miller <davem@davemloft.net>
CC: Ulrich Drepper <drepper@redhat.com>
CC: Rusty Russell <rusty@rustcorp.com.au>
CC: Gregory Haskins <ghaskins@novell.com>
CC: Arnaldo Carvalho de Melo <acme@redhat.com>
CC: "Luis Claudio R. Goncalves" <lclaudio@uudg.org>
CC: Clark Williams <williams@redhat.com>
CC: Christoph Lameter <cl@linux-foundation.org>
CC: Andi Kleen <andi@firstfloor.org>
CC: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: H. Peter Anvin <hpa@zytor.com>
ladder governor only honored latency requirement when promoting C-states.
Instead. it should check for latency requirement on each idle call,
and demote to appropriate C-state when there is a latency requirement change.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
There is a bug in menu governor where we have
if (data->elapsed_us < data->elapsed_us + measured_us)
with measured_us already having elapsed_us added in tickless case here
unsigned int measured_us =
cpuidle_get_last_residency(dev) + data->elapsed_us;
Also, it should be last_residency, not measured_us, that need to be used to
do comparing and distinguish between expected & non-expected events.
Refactor menu_reflect() to fix these two problems.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Wei Gang <gang.wei@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
poll_idle was added to CPUIDLE, just as a low latency idle handler, to be
used in cases when user desires CPUs not to enter any idle state at all. It
was supposed to be a run time idle=poll option to the user. But, it was indeed
getting used during normal menu and ladder governor default case, with no
special user setting (Reported by Linus Torvalds).
Change below ensures that poll_idle will not be used unless user explicitly
asks pm_qos infrastructure for zero latency requirement.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Not all AMD K8 have 6 VID pins, contrary to what was assumed in
commit 116d0486bd. This commit broke
support of older CPU models which have only 5 VID pins:
http://bugzilla.kernel.org/show_bug.cgi?id=11329
We need two entries in the hwmon-vid table, one for 5-bit VID models
(K8 revision <= E) and one for 6-bit VID models (K8 revision >= F).
This fixes bug #11329.
Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Frank Myhr <fmyhr@fhmtech.com>
Tested-by: Jean-Luc Coulon <jean.luc.coulon@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
as per this discussion:
http://lkml.org/lkml/2008/8/12/423
Pardo reported that 64-bit threaded apps, if their stacks exceed the
combined size of ~4GB, slow down drastically in pthread_create() - because
glibc uses MAP_32BIT to allocate the stacks. The use of MAP_32BIT is
a legacy hack - to speed up context switching on certain early model
64-bit P4 CPUs.
So introduce a new flag to be used by glibc instead, to not constrain
64-bit apps like this.
glibc can switch to this new flag straight away - it will be ignored
by the kernel. If those old CPUs ever matter to anyone, support for
it can be implemented.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Ulrich Drepper <drepper@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
The check for max physical address was incorrect, thus limiting the
range of allowed physical addresses.
Signed-off-by: Dave Olson <dave.olson@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
If a UD QP has some work requests queued to be sent by the DMA engine
followed by a local loopback work request, we have to wait for the
previous work requests to finish or the completion for the local
loopback work request would be generated out of order. The problem
was that the work request queue pointer was already updated so that
the request would not be processed when the DMA queue drained.
Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/sfrench/cifs-2.6:
[CIFS] mount of IPC$ breaks with iget patch
[CIFS] remove trailing whitespace
[CIFS] if get root inode fails during mount, cleanup tree connection
This moves it to being a tty operation. That removes special cases and now
also means that resize can be picked up by um and other non vt consoles
which may have a resize operation.
Signed-off-by: Alan Cox <alan@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'linux-next' of git://git.infradead.org/~dedekind/ubifs-2.6: (29 commits)
UBIFS: xattr bugfixes
UBIFS: remove unneeded check
UBIFS: few commentary fixes
UBIFS: fix budgeting request alignment in xattr code
UBIFS: improve arguments checking in debugging messages
UBIFS: always set i_generation to 0
UBIFS: correct spelling of "thrice".
UBIFS: support splice_write
UBIFS: minor tweaks in commit
UBIFS: reserve more space for index
UBIFS: print pid in dump function
UBIFS: align inode data to eight
UBIFS: improve budgeting checks
UBIFS: correct orphan deletion order
UBIFS: fix typos in comments
UBIFS: do not union creat_sqnum and del_cmtno
UBIFS: optimize deletions
UBIFS: increment commit number earlier
UBIFS: remove another unneeded function parameter
UBIFS: remove unneeded function parameter
...
If CONFIG_PROVE_LOCKING not defined, then no dependency information
is available.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
as per this discussion:
http://lkml.org/lkml/2008/8/12/423
Pardo reported that 64-bit threaded apps, if their stacks exceed the
combined size of ~4GB, slow down drastically in pthread_create() - because
glibc uses MAP_32BIT to allocate the stacks. The use of MAP_32BIT is
a legacy hack - to speed up context switching on certain early model
64-bit P4 CPUs.
So introduce a new flag to be used by glibc instead, to not constrain
64-bit apps like this.
glibc can switch to this new flag straight away - it will be ignored
by the kernel. If those old CPUs ever matter to anyone, support for
it can be implemented.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Acked-by: Ulrich Drepper <drepper@gmail.com>
WARNING: vmlinux.o(.text+0x17a3e): Section mismatch in reference from the function set_pte_vaddr_pud() to the function .init.text:spp_getpage()
The function set_pte_vaddr_pud() references
the function __init spp_getpage().
This is often because set_pte_vaddr_pud lacks a __init
annotation or the annotation of spp_getpage is wrong.
spp_getpage is called from __init (__init_extra_mapping) and
non __init (set_pte_vaddr_pud) functions, so it can't be __init.
Unfortunately it calls alloc_bootmem_pages which is __init,
but does it only when bootmem allocator is available (after_bootmem == 0).
So annotate it accordingly.
Signed-off-by: Marcin Slusarz <marcin.slusarz@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Cc: H. Peter Anvin <hpa@zytor.com>
By writing directly, a memory access violation can occur whilst
hotplugging a CPU if the entry was previously marked read-only.
Signed-off-by: Alex Nixon <alex.nixon@citrix.com>
Cc: Jeremy Fitzhardinge <Jeremy.Fitzhardinge@citrix.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'for-linus' of git://neil.brown.name/md:
md: cancel check/repair requests when recovery is needed
Allow raid10 resync to happening in larger chunks.
Allow faulty devices to be removed from a readonly array.
Don't let a blocked_rdev interfere with read request in raid5/6
Fail safely when trying to grow an array with a write-intent bitmap.
Restore force switch of md array to readonly at reboot time.
Make writes to md/safe_mode_delay immediately effective.
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input:
Input: xilinx_ps2 - fix warning
Input: bcm5974 - implement autosuspend support
Input: bcm5974 - add driver for Macbook Air and Pro Penryn touchpads
Input: paper over a bug in Synaptics X driver
Input: evdev - split EVIOCGBIT handlig into a separate function
Input: i8042 - Add Dritek quirk for Acer TravelMate 4280
Input: xpad - add Pelican Eclipse D-Pad to the list of devices
Input: gpio-keys - make gpio_keys_device_driver static
Input: gpio-keys - fix possible NULL pointer dereference
Input: wm97xx - enable sub-drivers by default
* 'release-2.6.27' of git://git.kernel.org/pub/scm/linux/kernel/git/ak/linux-acpi-2.6:
ACPI: Fix thermal shutdowns
ACPI: bounds check IRQ to prevent memory corruption
ACPI: Avoid bogus EC timeout when EC is in Polling mode
ACPI : Add the EC dmi table to fix the incorrect ECDT table
ACPI: Properly clear flags on false-positives and send uevent on sudden unplug
acpi: trivial cleanups
acer-wmi: Fix wireless and bluetooth on early AMW0 v2 laptops
ACPI: WMI: Set instance for query block calls
ACPICA: Additional error checking for pathname utilities
ACPICA: Fix possible memory leak in Unload() operator
ACPICA: Fix memory leak when deleting thermal/processor objects
David reported that his Niagra spend a little too much time in
tg_shares_up(), which considering he has a large cpu count makes sense.
So scale the ratelimit value with the number of cpus like we do for
other controls as well.
Reported-by: David Miller <davem@davemloft.net>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Sam Ravnborg did the build-test that the direct header file move works,
I'm just committing it.
This is a pure move:
mkdir arch/alpha/include
git mv include/asm-alpha arch/alpha/include/asm
with no other changes.
Requested-and-tested-by: Sam Ravnborg <sam@ravnborg.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Jean Delvare's machine triggered this BUG
acpi_os_map_memory phys ffff0000 size 65535
------------[ cut here ]------------
kernel BUG at arch/x86/mm/pat.c:233!
with ACPI in the backtrace.
Adding some debugging output showed that ACPI calls
acpi_os_map_memory phys ffff0000 size 65535
And ioremap/PAT does this check in 32bit, so addr+size wraps and the BUG
in reserve_memtype() triggers incorrectly.
BUG_ON(start >= end); /* end is exclusive */
But reserve_memtype already uses u64:
int reserve_memtype(u64 start, u64 end,
so the 32bit truncation must happen in the caller. Presumably in ioremap
when it passes this information to reserve_memtype().
This patch does this computation in 64bit.
http://bugzilla.kernel.org/show_bug.cgi?id=11346
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Fix coding style of traps_64.c with improvements suggested by Ingo.
Signed-off-by: Gustavo F. Padovan <gustavo@las.ic.unicamp.br>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In the initialization of the RCU trace module, if
rcupreempt_debugfs_init() fails, we never free the the trace buffer.
This patch frees the trace buffer in case the debugfs fails.
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Reviewed-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Seems that I found a box that has a config that passes call_rcu_bh as a
function pointer (see net/sctp/sm_make_chunk.c), so declaring the
call_rcu_bh has a macro function isn't good enough.
This patch makes it just another name of call_rcu for rcupreempt.
Signed-off-by: Steven Rostedt <srostedt@redhat.org>
Reviewed-by: "Paul E. McKenney" <paulmck@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The latest revisions of the WM8990 provide a programmable gain amplifier
for the speaker - configure the register cache and implement controls
for this. Older revisions of the device ignore writes to these controls.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
A fuzzed fileystem image failed with OMFS when the extent count was
used in a loop without being checked against the max number of extents.
It also provoked a signed division for an array index that was checked
as if unsigned, leading to index by -1.
omfsck will be updated to fix these cases, in the meantime bail out
gracefully.
Reported-by: Eric Sesterhenn <snakebyte@gmx.de>
Signed-off-by: Bob Copeland <me@bobcopeland.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
m68k fails to build with these functions inlined in completion.h. Move
them out of line into sched.c and export them to avoid this problem.
Signed-off-by: Dave Chinner <david@fromorbit.com>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
When reviewing a recent patch I noticed a potential trouble spot in the
registration of new SPI devices. The SPI master driver is told to set
the device up before adding it to the driver model, so that it's always
properly set up when probe() is called. (This is important, because in
the case of inverted chipselects, this device can make the bus misbehave
until it's properly deselected. It's got to be set up even if no driver
binds to the device.)
The trouble spot is that it doesn't first verify that no other device
has been added using that chipselect. If such a device has been added,
its configuration gets trashed. (Fortunately this has not been a common
error!)
The fix here adds an explicit check, and a mutex to protect the relevant
critical region.
[akpm@linux-foundation.org: make the lock local to spi_add_device()]
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
write_cache_pages() uses i_mapping->writeback_index to pick up where it
left off the last time a given inode was found by pdflush or
balance_dirty_pages (or anyone else who sets wbc->range_cyclic)
alloc_inode() should set it to a sane value so that writeback doesn't
start in the middle of a file. It is somewhat difficult to notice the bug
since write_cache_pages will loop around to the start of the file and the
elevator helps hide the resulting seeks.
For whatever reason, Btrfs hits this often. Unpatched, untarring 30
copies of the linux kernel in series runs at 47MB/s on a single sata
drive. With this fix, it jumps to 62MB/s.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add MAINTAINERS for GRU, XPNET, XPC and XP drivers.
Signed-off-by: Jack Steiner <steiner@sgi.com>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add in the CPUID for Nehalem chips.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Cc: Kent Liu <kent.liu@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Currently, all sensors are read when the energy meter is queried via
sysfs. This introduces a considerable amount of delay and variation in
the sysfs reading, which is not desirable when trying to profile energy
use. Therefore, read only the energy meters when a sysfs query comes in
for them, and don't cache the results so that we always get the latest
reading.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
On older machines, probing for a nonexistent AEM interface returned an
IPMI error; when we saw this, we'd stop probing. On the x3650 M2 and
(presumably) later, we are returned a value indicating success and a
buffer full of garbage or zeroes. This causes the probe function to run
in an infinite loop. To fix this, we add one last check--if the
interface number we're looking for is higher than the number of
interfaces that AEM claims to have, stop probing.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Minor documentation update to reflect the current full name of the power
management hardware interface and reflows the text a bit.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Previously the driver was only using DMI to prevent smbus probing on
non-Abit motherboards. However, since the manual probing method is
brittle and prone to failure on some Abit motherboards (esp. the Abit
IP35 Pro) it is better to use DMI to also read the board name and then
decide whether or not to probe the bus.
At the moment, we do not have a list of valid DMI name strings to use
for existing and supported motherboards. This patch only implements DMI
probing for the IP35 Pro. For motherboards that can not yet use DMI
probing, a warning will be printed to the kernel log asking those users
to email me their dmidecode output.
The existing manual probing mechanism will be used if CONFIG_DMI is not
enabled, if DMI probing fails (for DMI-unsupported motherboards), or if
DMI probing fails and the "force" option is set (for DMI-supported
motherboards). Ideally in the longer term this manual probing method
would be removed.
This patch should be safe to apply as it does not change the probing
behaviour for most of the supported motherboards, just the IP35 Pro,
which already has regressions filed against it in 2.6.26.
Addresses http://bugzilla.kernel.org/show_bug.cgi?id=11212
Signed-off-by: Alistair John Strachan <alistair@devzero.co.uk>
Acked-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Hans passed maintainership of the abituguru3 hwmon driver onto me. Add
a new entry to the MAINTAINERS file for the abituguru3 driver and assign
it to me. Also update the existing UGURU entry to indicate that Hans is
only responsible for the abituguru driver.
Signed-off-by: Alistair John Strachan <alistair@devzero.co.uk>
Acked-by: Hans de Goede <j.w.r.degoede@hhs.nl>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Export the sensor -> channel/dimm mapping in tempX_label.
Signed-off-by: Darrick J. Wong <djwong@us.ibm.com>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
SPI driver for analog to digital converters national semiconductor
ADC081S101, ADC124S501, ...
Code for 8 channels by Tobias Himmer.
This driver adds support for National Semiconductor ADC<bb><c>S<sss> chip
family, where:
* bb is the resolution in number of bits (8, 10, 12)
* c is the number of channels (1, 2, 4, 8)
* sss is the maximum conversion speed (021 for 200 kSPS, 051 for 500
kSPS and 101 for 1 MSPS)
[akpm@linux-foundation.org: coding-style fixes]
Signed-off-by: Marc Pignat <marc.pignat@hevs.ch>
Cc: Tobias Himmer <tobias@himmer-online.de>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: David Brownell <david-b@pacbell.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Add support for Macbook v3 (sensors and accelerometer).
Signed-off-by: Nicolas Boichat <nicolas@boichat.ch>
Cc: "Mark M. Hoffman" <mhoffman@lightlink.com>
Cc: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This adds support for fans and temperature sensors on intel iMac.
Tested on iMac 24" 2.8ghz (iMac8,1), it supports the following sensors:
cpu A
ambient
gpu
gpu diode
gpu heatsink
hd bay 1
memory controller
optical drive
power
Signed-off-by: Roberto De Ioris <roberto@unbit.it>
Cc: Nicolas Boichat <nicolas@boichat.ch>
Cc: Jean Delvare <khali@linux-fr.org>
Cc: Mark M. Hoffman <mhoffman@lightlink.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
AOI position cannot be negative.
Signed-off-by: York Sun <yorksun@freescale.com>
Cc: Kumar Gala <galak@gate.crashing.org>
Cc: "Antonino A. Daplas" <adaplas@pol.net>
Cc: Krzysztof Helt <krzysztof.h1@poczta.fm>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
