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- CAFE_CCIC needs to depend on PCI, else "allyesconfig" breaks
on systems without PCI
- em28xx-video can't udelay(2500) else "allyesconfig" breaks
on systems that refuse to spin that long (I saw it on ARM)
Signed-off-by: David Brownell <dbrownell@users.sourceforge.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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ioremap() is called twice to same resource.
The returen value of first one is not error-checked.
second one is complely ignored.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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The return value of kthread_run() should be checked by IS_ERR().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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The return value of kthread_run() should be checked by IS_ERR().
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Freeing data including list_head in list_for_each() is not safe.
Signed-off-by: Akinobu Mita <akinobu.mita@gmail.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Fix a typo (use_frontent -> use_frontend) in saa7134-dvb.c.
Signed-off-by: Stephan Berberig <s.berberig@arcor.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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We shouldn't dereference "cam" when we already know it's NULL.
Spotted by the Coverity checker.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Free previously allocated memory (in array elements) if kmalloc() returns
NULL in submit_urbs().
Signed-off-by: Amit Choudhary <amit2030@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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This bug broke the MPEG audio mode controls.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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The temporal filter is forced off when scaling. The VIDIOC_LOG_STATUS
handler still showed the old temporal filter. It is now consistent with
the real temporal filter value.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Change the code to unconditionally turn off the temporal filter when scaling.
If the window is not full screen the filter will introduce a nasty ghosting
effect.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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The wrong matrix was used when an external input was selected instead of
the tuner input. The rxsubchans field was also not initialized to STEREO
for an external input. And finally the msp34xxg_detect_stereo() should
not try to detect stereo for an external input, that code is for the
tuner input only.
Together these bugs made it hit 'n miss whether you ever got stereo out
of the msp3400 for an external input.
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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On cx88 driver, sampling rate should be at chroma subcarrier freq (FSC).
However, driver were programming wrong values for PAL/60, PAL/Nc and
NTSC 4.43. This patch do the proper calculation. It also calculates
htotal, hdelay and hactive constants, according with the sampling
rate.
It is tested with PAL/60 by Piotr Maksymuk and Olivier. Also tested with
the already-supported standards.
Test is still required for PAL/Nc.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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- SYSFS: Replaced all to_video_device(cd), video_device_create_file,
video_device_remove_file and add the proper checks at create_file
- Converted old norm values to V4L2 ones.
- Robustness on sysfs hue/contrast/saturation queries.
Additional check in order to return 0 if the driver is not opened.
- Whitespace cleanups in usbvision-cards.c
This patch merges two fixes by Thierry MERLE and Mauro Chehab, and adds
additional checks.
Signed-off-by: Dwaine Garden<DwaineGarden@rogers.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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dvb_net.c: In function 'dvb_net_ule':
dvb_net.c:628: warning: format '%#lx' expects type 'long unsigned int', but argument 3 has type 'u32'
dvb_net.c:628: warning: format '%#lx' expects type 'long unsigned int', but argument 4 has type 'u32'
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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CRC-32 checking during ULE decapsulation always failed on x86_64 systems due
to the size of a variable used to store CRC. This bug was discovered on
Fedora Core 6 with kernel-2.6.18-1.2849. The i386 counterpart has no such
problem. This patch has been tested on 64-bit system as well as 32-bit system.
Signed-off-by: Ang Way Chuang <wcang@nrg.cs.usm.my>
Signed-off-by: Michael Krufky <mkrufky@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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- fix decompression buffer allocation not done at first driver open
- simplification of USB sbuf allocation (use of usb_buffer_alloc)
- replaced vmalloc by vmalloc_32 (for homogeneity)
- add of saa7111 (i2cAddr=0x48) detection printout in attach_inform
Signed-off-by: Thierry MERLE <thierry.merle@free.fr>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Consistent handling of VIDEO_PALETTE_YUYV and VIDEO_PALETTE_YUV422
Signed-off-by: Andrea A Odetti <audetto@tiscali.it>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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i2c_adap is almost not used. This patch removes it, cleaning the i2c support,
and improving driver understanding.
Thanks to Thierry Merle for testing it.
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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This patch contains the following possible cleanups:
- make needlessly global functions static
- remove the unused EXPORT_SYMBOL's
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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Both use __SC. Since __* is sort of private namespace I've choosen to fix
this in the driver. For consistency I decieded to also change __UNSC to
UNSC.
Signed-off-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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This patch removes unnecessary (and misleading) debug
output (it printed the values of the keys in the table up to the value
of the key pressed).
Signed-off-by: Mario Rossi <mariofutire@googlemail.com>
Signed-off-by: Patrick Boettcher <pb@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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After rewriting the driver the wrong autosearch index was used when
COFDM-parameter needed to be detected.
Thanks to Mario Rossi who found it.
Signed-off-by: Mario Rossi <mariofutire@googlemail.com>
Signed-off-by: Patrick Boettcher <pb@linuxtv.org>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
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This also adds he required page "writeback" flag handling, that cifs
hasn't been doing and that the page dirty flag changes made obvious.
Acked-by: Steve French <smfltc@us.ibm.com>
Acked-by: Dave Kleikamp <shaggy@linux.vnet.ibm.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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We use the fixmap for accessing pci config space in pci_mmcfg_read/write().
The problem is in pci_exp_set_dev_base(). It is caching a last
accessed address to avoid calling set_fixmap_nocache() whenever
pci_mmcfg_read/write() is used.
static inline void pci_exp_set_dev_base(int bus, int devfn)
{
u32 dev_base = base | (bus << 20) | (devfn << 12);
if (dev_base != mmcfg_last_accessed_device) {
mmcfg_last_accessed_device = dev_base;
set_fixmap_nocache(FIX_PCIE_MCFG, dev_base);
}
}
cpu0 cpu1
---------------------------------------------------------------------------
pci_mmcfg_read("device-A")
pci_exp_set_dev_base()
set_fixmap_nocache()
pci_mmcfg_read("device-B")
pci_exp_set_dev_base()
set_fixmap_nocache()
pci_mmcfg_read("device-B")
pci_exp_set_dev_base()
/* doesn't flush tlb */
But if cpus accessed the above order, the second pci_mmcfg_read() on
cpu0 doesn't flush the TLB, because "mmcfg_last_accessed_device" is
device-B. So, second pci_mmcfg_read() on cpu0 accesses a device-A via
a previous TLB cache. This problem became the cause of several strange
behavior.
This patches fixes this situation by adds "mmcfg_last_accessed_cpu" check.
[ Alternatively, we could make a per-cpu mapping area or something. Not
that it's probably worth it, but if we wanted to avoid all locking and
instead just disable preemption, that would be the way to go. --Linus ]
Signed-off-by: OGAWA Hirofumi <hogawa@miraclelinux.com>
Signed-off-by: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Clark Williams reported that suspend doesnt work on his laptop on
2.6.20-rc1-rt kernels. The bug was introduced by the following cleanup
commit:
commit 112cecb2cc0e7341db92281ba04b26c41bb8146d
Author: Siddha, Suresh B <suresh.b.siddha@intel.com>
Date: Wed Dec 6 20:34:31 2006 -0800
[PATCH] suspend: don't change cpus_allowed for task initiating the suspend
because with this change 'error' is not initialized to 0 anymore, if
there are no other online CPUs. (i.e. if the system is single-CPU).
the fix is the initialize it to 0. The really weird thing is that my
version of gcc does not warn about this non-initialized variable
situation ...
(also fix the kernel printk in the error branch, it was missing a
newline)
Reported-by: Clark Williams <williams@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Thanks to Len Brown for testing this fix, since while they have in the
past, none of my machines run reiserfs at the moment.
Cc: Vladimir V. Saveliev <vs@namesys.com>
Acked-by: Len Brown <lenb@kernel.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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Make cancel_dirty_page() act more like all the other dirty and writeback
accounting functions: test for "mapping" being NULL, and do the
NR_FILE_DIRY accounting purely based on mapping_cap_account_dirty()).
Also, add it to the exports, so that modular filesystems can use it.
Acked-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6
* 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: (68 commits)
ACPI: replace kmalloc+memset with kzalloc
ACPI: Add support for acpi_load_table/acpi_unload_table_id
fbdev: update after backlight argument change
ACPI: video: Add dev argument for backlight_device_register
ACPI: Implement acpi_video_get_next_level()
ACPI: Kconfig - depend on PM rather than selecting it
ACPI: fix NULL check in drivers/acpi/osl.c
ACPI: make drivers/acpi/ec.c:ec_ecdt static
ACPI: prevent processor module from loading on failures
ACPI: fix single linked list manipulation
ACPI: ibm_acpi: allow clean removal
ACPI: fix git automerge failure
ACPI: ibm_acpi: respond to workqueue update
ACPI: dock: add uevent to indicate change in device status
ACPI: ec: Lindent once again
ACPI: ec: Change #define to enums there possible.
ACPI: ec: Style changes.
ACPI: ec: Acquire Global Lock under EC mutex.
ACPI: ec: Drop udelay() from poll mode. Loop by reading status field instead.
ACPI: ec: Rename gpe_bit to gpe
...
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The function isdn_ppp_ccp_reset_alloc_state() sets ->timer.function
and ->timer.data and later on calls add_timer() with no init_timer()
ever done.
Noted by Al Viro.
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: Karsten Keil <kkeil@suse.de>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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* master.kernel.org:/pub/scm/linux/kernel/git/davem/net-2.6:
[UDP]: Fix reversed logic in udp_get_port().
[IPV6]: Dumb typo in generic csum_ipv6_magic()
[SCTP]: make 2 functions static
[SCTP]: Fix typo adaption -> adaptation as per the latest API draft.
[SCTP]: Don't export include/linux/sctp.h to userspace.
[TCP]: Fix ambiguity in the `before' relation.
[ATM] drivers/atm/fore200e.c: Cleanups.
[ATM]: Remove dead ATM_TNETA1570 option.
NetLabel: correctly fill in unused CIPSOv4 level and category mappings
NetLabel: perform input validation earlier on CIPSOv4 DOI add ops
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The logic in cfq_allow_merge() wasn't clear enough - basically allow
merging for the same queues only. Do a fast check for 'rq and bio both
sync/async' before doing the cfqq hash lookup.
This is verified to work with the fixed elv_try_merge() from commit
bb4067e34159648d394943d5e2a011f838bff22f.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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When this code was converted to use sk_for_each() the
logic for the "best hash chain length" code was reversed,
breaking everything.
The original code was of the form:
size = 0;
do {
if (++size >= best_size_so_far)
goto next;
} while ((sk = sk->next) != NULL);
best_size_so_far = size;
best = result;
next:;
and this got converted into:
sk_for_each(sk2, node, head)
if (++size < best_size_so_far) {
best_size_so_far = size;
best = result;
}
Which does something very very different from the original.
Signed-off-by: David S. Miller <davem@davemloft.net>
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... duh
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch makes the following needlessly global functions static:
- ipv6.c: sctp_inet6addr_event()
- protocol.c: sctp_inetaddr_event()
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Signed-off-by: Ivan Skytte Jorgensen <isj-sctp@i1.dk>
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This file contains protocol definitions and there are no SCTP apps
that use this file.
Signed-off-by: Sridhar Samudrala <sri@us.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
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While looking at DCCP sequence numbers, I stumbled over a problem with
the following definition of before in tcp.h:
static inline int before(__u32 seq1, __u32 seq2)
{
return (__s32)(seq1-seq2) < 0;
}
Problem: This definition suffers from an an ambiguity, i.e. always
before(a, (a + 2^31) % 2^32)) = 1
before((a + 2^31) % 2^32), a) = 1
In text: when the difference between a and b amounts to 2^31,
a is always considered `before' b, the function can not decide.
The reason is that implicitly 0 is `before' 1 ... 2^31-1 ... 2^31
Solution: There is a simple fix, by defining before in such a way that
0 is no longer `before' 2^31, i.e. 0 `before' 1 ... 2^31-1
By not using the middle between 0 and 2^32, before can be made
unambiguous.
This is achieved by testing whether seq2-seq1 > 0 (using signed
32-bit arithmetic).
I attach a patch to codify this. Also the `after' relation is basically
a redefinition of `before', it is now defined as a macro after before.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch contains the following transformations from custom functions
to standard kernel version:
- fore200e_kmalloc() -> kzalloc()
- fore200e_kfree() -> kfree()
- fore200e_swap() -> cpu_to_be32()
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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This patch removes the unconverted ATM_TNETA1570 option that also lacks
any code in the kernel.
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: David S. Miller <davem@davemloft.net>
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Back when the original NetLabel patches were being changed to use Netlink
attributes correctly some code was accidentially dropped which set all of the
undefined CIPSOv4 level and category mappings to a sentinel value. The result
is the mappings data in the kernel contains bogus mappings which always map to
zero. This patch restores the old/correct behavior by initializing the mapping
data to the correct sentinel value.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
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There are a couple of cases where the user input for a CIPSOv4 DOI add
operation was not being done soon enough; the result was unexpected behavior
which was resulting in oops/panics/lockups on some platforms. This patch moves
the existing input validation code earlier in the code path to protect against
bogus user input.
Signed-off-by: Paul Moore <paul.moore@hp.com>
Signed-off-by: James Morris <jmorris@namei.org>
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- add flush_cache_page() for all those virtual indexed cache
architectures.
- handle s390.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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The uartlite driver used to always enable the port even if request_port
failed causing havoc. This patch fixes it.
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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This patch fixes the case when we reparent to a different thread in the
same thread group. This modifies the code so that we do not send
signals and do not change the signal to send to SIGCHLD unless we have
change the thread group of our parents. It also suppresses sending
pdeath_sig in this cas as well since the result of geppid doesn't
change.
Thanks to Oleg for spotting my bug of only fixing this for non-ptraced
tasks.
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Albert Cahalan <acahalan@gmail.com>
Cc: Andrew Morton <akpm@osdl.org>
Cc: Roland McGrath <roland@redhat.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Coywolf Qi Hunt <qiyong@fc-cn.com>
Acked-by: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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compile.h is created super-late in the build. But proc_misc.c want to include
it, and it's generally not sane to have a header file in include/linux be
created at the end of the build: it's either not present or, worse, wrong for
most of the build.
So the patch arranges for compile.h to be built at the start of the build
process. It also consolidates the compile.h rules with those for version.h
and utsname.h, so they all get built together.
I hope. My chances of having got this right are about 2%.
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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APM idle code
Fernando Lopez-Lezcano reported frequent scheduling latencies and audio
xruns starting at the 2.6.18-rt kernel, and those problems persisted all
until current -rt kernels. The latencies were serious and unjustified by
system load, often in the milliseconds range.
After a patient and heroic multi-month effort of Fernando, where he
tested dozens of kernels, tried various configs, boot options,
test-patches of mine and provided latency traces of those incidents, the
following 'smoking gun' trace was captured by him:
_------=> CPU#
/ _-----=> irqs-off
| / _----=> need-resched
|| / _---=> hardirq/softirq
||| / _--=> preempt-depth
|||| /
||||| delay
cmd pid ||||| time | caller
\ / ||||| \ | /
IRQ_19-1479 1D..1 0us : __trace_start_sched_wakeup (try_to_wake_up)
IRQ_19-1479 1D..1 0us : __trace_start_sched_wakeup <<...>-5856> (37 0)
IRQ_19-1479 1D..1 0us : __trace_start_sched_wakeup (c01262ba 0 0)
IRQ_19-1479 1D..1 0us : resched_task (try_to_wake_up)
IRQ_19-1479 1D..1 0us : __spin_unlock_irqrestore (try_to_wake_up)
...
<idle>-0 1...1 11us!: default_idle (cpu_idle)
...
<idle>-0 0Dn.1 602us : smp_apic_timer_interrupt (c0103baf 1 0)
...
<...>-5856 0D..2 618us : __switch_to (__schedule)
<...>-5856 0D..2 618us : __schedule <<idle>-0> (20 162)
<...>-5856 0D..2 619us : __spin_unlock_irq (__schedule)
<...>-5856 0...1 619us : trace_stop_sched_switched (__schedule)
<...>-5856 0D..1 619us : trace_stop_sched_switched <<...>-5856> (37 0)
what is visible in this trace is that CPU#1 ran try_to_wake_up() for
PID:5856, it placed PID:5856 on CPU#0's runqueue and ran resched_task()
for CPU#0. But it decided to not send an IPI that no CPU - due to
TS_POLLING. But CPU#0 never woke up after its NEED_RESCHED bit was set,
and only rescheduled to PID:5856 upon the next lapic timer IRQ. The
result was a 600+ usecs latency and a missed wakeup!
the bug turned out to be an idle-wakeup bug introduced into the mainline
kernel this summer via an optimization in the x86_64 tree:
commit 495ab9c045e1b0e5c82951b762257fe1c9d81564
Author: Andi Kleen <ak@suse.de>
Date: Mon Jun 26 13:59:11 2006 +0200
[PATCH] i386/x86-64/ia64: Move polling flag into thread_info_status
During some profiling I noticed that default_idle causes a lot of
memory traffic. I think that is caused by the atomic operations
to clear/set the polling flag in thread_info. There is actually
no reason to make this atomic - only the idle thread does it
to itself, other CPUs only read it. So I moved it into ti->status.
the problem is this type of change:
if (!hlt_counter && boot_cpu_data.hlt_works_ok) {
- clear_thread_flag(TIF_POLLING_NRFLAG);
+ current_thread_info()->status &= ~TS_POLLING;
smp_mb__after_clear_bit();
while (!need_resched()) {
local_irq_disable();
this changes clear_thread_flag() to an explicit clearing of TS_POLLING.
clear_thread_flag() is defined as:
clear_bit(flag, &ti->flags);
and clear_bit() is a LOCK-ed atomic instruction on all x86 platforms:
static inline void clear_bit(int nr, volatile unsigned long * addr)
{
__asm__ __volatile__( LOCK_PREFIX
"btrl %1,%0"
hence smp_mb__after_clear_bit() is defined as a simple compile barrier:
#define smp_mb__after_clear_bit() barrier()
but the explicit TS_POLLING clearing introduced by the patch:
+ current_thread_info()->status &= ~TS_POLLING;
is not an atomic op! So the clearing of the TS_POLLING bit is freely
reorderable with the reading of the NEED_RESCHED bit - and both now
reside in different memory addresses.
CPU idle wakeup very much depends on ordered memory ops, the clearing of
the TS_POLLING flag must always be done before we test need_resched()
and hit the idle instruction(s). [Symmetrically, the wakeup code needs
to set NEED_RESCHED before it tests the TS_POLLING flag, so memory
ordering is paramount.]
Fernando's dual-core Athlon64 system has a sufficiently advanced memory
ordering model so that it triggered this scenario very often.
( And it also turned out that the reason why these latencies never
triggered on my testsystems is that i routinely use idle=poll, which
was the only idle variant not affected by this bug. )
The fix is to change the smp_mb__after_clear_bit() to an smp_mb(), to
act as an absolute barrier between the TS_POLLING write and the
NEED_RESCHED read. This affects almost all idling methods (default,
ACPI, APM), on all 3 x86 architectures: i386, x86_64, ia64.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Tested-by: Fernando Lopez-Lezcano <nando@ccrma.Stanford.EDU>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
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