Provide a shared interrupt debug facility under CONFIG_DEBUG_SHIRQ:
it uses the existing irqpoll facilities to iterate through all
registered interrupt handlers and call those which can handle shared
IRQ lines.
This can be handy for suspend/resume debugging: if we call this function
early during resume we can trigger crashes in those drivers which have
incorrect assumptions about when exactly their ISRs will be called
during suspend/resume.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev:
sata_fsl: Return non-zero on error in probe()
drivers/ata/pata_ali.c: s/isa_bridge/ali_isa_bridge/ to fix alpha build
libata: New driver for OCTEON SOC Compact Flash interface (v7).
libata: Add another column to the ata_timing table.
sata_via: Add VT8261 support
pata_atiixp: update port enabledness test handling
[libata] get-identity ioctl: Fix use of invalid memory pointer
The forthcoming OCTEON SOC Compact Flash driver needs an additional
timing value that was not available in the ata_timing table. I add a
new column for dmack_hold time. The values were obtained from the
Compact Flash specification Rev 4.1.
Signed-off-by: David Daney <ddaney@caviumnetworks.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
for SAS drivers.
Caught by Ke Wei (and team?) at Marvell.
Also, move the ata_scsi_ioctl export to libata-scsi.c, as that seems to be the
general trend.
Acked-by: James Bottomley <James.Bottomley@HansenPartnership.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
It is an optimization and a cleanup, and adds the following new
generic percpu methods:
percpu_read()
percpu_write()
percpu_add()
percpu_sub()
percpu_and()
percpu_or()
percpu_xor()
and implements support for them on x86. (other architectures will fall
back to a default implementation)
The advantage is that for example to read a local percpu variable,
instead of this sequence:
return __get_cpu_var(var);
ffffffff8102ca2b: 48 8b 14 fd 80 09 74 mov -0x7e8bf680(,%rdi,8),%rdx
ffffffff8102ca32: 81
ffffffff8102ca33: 48 c7 c0 d8 59 00 00 mov $0x59d8,%rax
ffffffff8102ca3a: 48 8b 04 10 mov (%rax,%rdx,1),%rax
We can get a single instruction by using the optimized variants:
return percpu_read(var);
ffffffff8102ca3f: 65 48 8b 05 91 8f fd mov %gs:0x7efd8f91(%rip),%rax
I also cleaned up the x86-specific APIs and made the x86 code use
these new generic percpu primitives.
tj: * fixed generic percpu_sub() definition as Roel Kluin pointed out
* added percpu_and() for completeness's sake
* made generic percpu ops atomic against preemption
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Tejun Heo <tj@kernel.org>
[ Based on original patch from Christoph Lameter and Mike Travis. ]
Currently pdas and percpu areas are allocated separately. %gs points
to local pda and percpu area can be reached using pda->data_offset.
This patch folds pda into percpu area.
Due to strange gcc requirement, pda needs to be at the beginning of
the percpu area so that pda->stack_canary is at %gs:40. To achieve
this, a new percpu output section macro - PERCPU_VADDR_PREALLOC() - is
added and used to reserve pda sized chunk at the start of the percpu
area.
After this change, for boot cpu, %gs first points to pda in the
data.init area and later during setup_per_cpu_areas() gets updated to
point to the actual pda. This means that setup_per_cpu_areas() need
to reload %gs for CPU0 while clearing pda area for other cpus as cpu0
already has modified it when control reaches setup_per_cpu_areas().
This patch also removes now unnecessary get_local_pda() and its call
sites.
A lot of this patch is taken from Mike Travis' "x86_64: Fold pda into
per cpu area" patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
[ Based on original patch from Christoph Lameter and Mike Travis. ]
This patch makes percpu symbols zerobased on x86_64 SMP by adding
PERCPU_VADDR() to vmlinux.lds.h which helps setting explicit vaddr on
the percpu output section and using it in vmlinux_64.lds.S. A new
PHDR is added as existing ones cannot contain sections near address
zero. PERCPU_VADDR() also adds a new symbol __per_cpu_load which
always points to the vaddr of the loaded percpu data.init region.
The following adjustments have been made to accomodate the address
change.
* code to locate percpu gdt_page in head_64.S is updated to add the
load address to the gdt_page offset.
* __per_cpu_load is used in places where access to the init data area
is necessary.
* pda->data_offset is initialized soon after C code is entered as zero
value doesn't work anymore.
This patch is mostly taken from Mike Travis' "x86_64: Base percpu
variables at zero" patch.
Signed-off-by: Tejun Heo <tj@kernel.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Decoupling allows:
* hung tasks check to happen at very low priority
* hung tasks check and softlockup to be enabled/disabled independently
at compile and/or run-time
* individual panic settings to be enabled disabled independently
at compile and/or run-time
* softlockup threshold to be reduced without increasing hung tasks
poll frequency (hung task check is expensive relative to softlock watchdog)
* hung task check to be zero over-head when disabled at run-time
Signed-off-by: Mandeep Singh Baines <msb@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Stephen Rothwell reported this linux-next build failure with !CONFIG_SCHEDSTATS:
| In file included from kernel/sched.c:1703:
| kernel/sched_fair.c: In function 'adaptive_gran':
| kernel/sched_fair.c:1324: error: 'struct sched_entity' has no member named 'avg_wakeup'
The start_runtime and avg_wakeup metrics are now not just for statistics,
but also for scheduling - so they always need to be available. (Also
move out the nr_migrations fields - for future perfcounters usage.)
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Merge header files for m68k and m68knommu to the single location:
arch/m68k/include/asm
The majority of this patch was the result of the
script that is included in the changelog below.
The script was originally written by Arnd Bergman and
exten by me to cover a few more files.
When the header files differed the script uses the following:
The original m68k file is named <file>_mm.h [mm for memory manager]
The m68knommu file is named <file>_no.h [no for no memory manager]
The files uses the following include guard:
This include gaurd works as the m68knommu toolchain set
the __uClinux__ symbol - so this should work in userspace too.
Merging the header files for m68k and m68knommu exposes the
(unexpected?) ABI differences thus it is easier to actually
identify these and thus to fix them.
The commit has been build tested with both a m68k and
a m68knommu toolchain - with success.
The commit has also been tested with "make headers_check"
and this patch fixes make headers_check for m68knommu.
The script used:
TARGET=arch/m68k/include/asm
SOURCE=arch/m68knommu/include/asm
INCLUDE="cachectl.h errno.h fcntl.h hwtest.h ioctls.h ipcbuf.h \
linkage.h math-emu.h md.h mman.h movs.h msgbuf.h openprom.h \
oplib.h poll.h posix_types.h resource.h rtc.h sembuf.h shmbuf.h \
shm.h shmparam.h socket.h sockios.h spinlock.h statfs.h stat.h \
termbits.h termios.h tlb.h types.h user.h"
EQUAL="auxvec.h cputime.h device.h emergency-restart.h futex.h \
ioctl.h irq_regs.h kdebug.h local.h mutex.h percpu.h \
sections.h topology.h"
NOMUUFILES="anchor.h bootstd.h coldfire.h commproc.h dbg.h \
elia.h flat.h m5206sim.h m520xsim.h m523xsim.h m5249sim.h \
m5272sim.h m527xsim.h m528xsim.h m5307sim.h m532xsim.h \
m5407sim.h m68360_enet.h m68360.h m68360_pram.h m68360_quicc.h \
m68360_regs.h MC68328.h MC68332.h MC68EZ328.h MC68VZ328.h \
mcfcache.h mcfdma.h mcfmbus.h mcfne.h mcfpci.h mcfpit.h \
mcfsim.h mcfsmc.h mcftimer.h mcfuart.h mcfwdebug.h \
nettel.h quicc_simple.h smp.h"
FILES="atomic.h bitops.h bootinfo.h bug.h bugs.h byteorder.h cache.h \
cacheflush.h checksum.h current.h delay.h div64.h \
dma-mapping.h dma.h elf.h entry.h fb.h fpu.h hardirq.h hw_irq.h io.h \
irq.h kmap_types.h machdep.h mc146818rtc.h mmu.h mmu_context.h \
module.h page.h page_offset.h param.h pci.h pgalloc.h \
pgtable.h processor.h ptrace.h scatterlist.h segment.h \
setup.h sigcontext.h siginfo.h signal.h string.h system.h swab.h \
thread_info.h timex.h tlbflush.h traps.h uaccess.h ucontext.h \
unaligned.h unistd.h"
mergefile() {
BASE=${1%.h}
git mv ${SOURCE}/$1 ${TARGET}/${BASE}_no.h
git mv ${TARGET}/$1 ${TARGET}/${BASE}_mm.h
cat << EOF > ${TARGET}/$1
EOF
git add ${TARGET}/$1
}
set -e
mkdir -p ${TARGET}
git mv include/asm-m68k/* ${TARGET}
rmdir include/asm-m68k
git rm ${SOURCE}/Kbuild
for F in $INCLUDE $EQUAL; do
git rm ${SOURCE}/$F
done
for F in $NOMUUFILES; do
git mv ${SOURCE}/$F ${TARGET}/$F
done
for F in $FILES ; do
mergefile $F
done
rmdir arch/m68knommu/include/asm
rmdir arch/m68knommu/include
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Greg Ungerer <gerg@uclinux.org>
When mode setting is first initialized, the driver will call into
drm_helper_initial_config() to set up an initial output and framebuffer
configuration. This routine is responsible for probing the available
connectors, encoders, and crtcs, looking for modes and putting together
something reasonable (where reasonable is defined as "allows kernel
messages to be visible on as many displays as possible").
However, the code was a bit too aggressive in setting default modes when
none were found on a given connector. Even if some connectors had modes,
any connectors found lacking modes would have the default 800x600 mode added
to their mode list, which in some cases could cause problems later down the
line. In my case, the LVDS was perfectly available, but the initial config
code added 800x600 modes to both of the detected but unavailable HDMI
connectors (which are on my non-existent docking station). This ended up
preventing later code from setting a mode on my LVDS, which is bad.
This patch fixes that behavior by making the initial config code walk
through the connectors first, counting the available modes, before it decides
to add any default modes to a possibly connected output. It also fixes the
logic in drm_target_preferred() that was causing zeroed out modes to be set
as the preferred mode for a given connector, even if no modes were available.
Signed-off-by: Jesse Barnes <jbarnes@virtuousgeek.org>
Signed-off-by: Eric Anholt <eric@anholt.net>
Signed-off-by: Dave Airlie <airlied@linux.ie>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (95 commits)
b44: GFP_DMA skb should not escape from driver
korina: do not use IRQF_SHARED with IRQF_DISABLED
korina: do not stop queue here
korina: fix handling tx_chain_tail
korina: do tx at the right position
korina: do schedule napi after testing for it
korina: rework korina_rx() for use with napi
korina: disable napi on close and restart
korina: reset resource buffer size to 1536
korina: fix usage of driver_data
bnx2x: First slow path interrupt race
bnx2x: MTU Filter
bnx2x: Indirection table initialization index
bnx2x: Missing brackets
bnx2x: Fixing the doorbell size
bnx2x: Endianness issues
bnx2x: VLAN tagged packets without VLAN offload
bnx2x: Protecting the link change indication
bnx2x: Flow control updated before reporting the link
bnx2x: Missing mask when calculating flow control
...
Impact: fix 15 make headers_check warnings:
include of <linux/types.h> is preferred over <asm/types.h>
Signed-off-by: Jaswinder Singh Rajput <jaswinderrajput@gmail.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Sam Ravnborg <sam@ravnborg.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Unlike other alphas, marvel doesn't have real PC-style CMOS clock hardware
- RTC accesses are emulated via PAL calls. Unfortunately, for unknown
reason these calls work only on CPU #0. So current implementation for
arbitrary CPU makes CMOS_READ/WRITE to be executed on CPU #0 via IPI.
However, for obvious reason this doesn't work with standard
get/set_rtc_time() functions, where a bunch of CMOS accesses is done with
disabled interrupts.
Solved by making the IPI calls for entire get/set_rtc_time() functions,
not for individual CMOS accesses. Which is also a lot more effective
performance-wise.
The patch is largely based on the code from Jay Estabrook.
My changes:
- tweak asm-generic/rtc.h by adding a couple of #defines to
avoid a massive code duplication in arch/alpha/include/asm/rtc.h;
- sys_marvel.c: fix get/set_rtc_time() return values (Jay's FIXMEs).
NOTE: this fixes *only* LIB_RTC drivers. Legacy (CONFIG_RTC) driver
wont't work on marvel. Actually I think that we should just disable
CONFIG_RTC on alpha (maybe in 2.6.30?), like most other arches - AFAIK,
all modern distributions use LIB_RTC anyway.
Signed-off-by: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Richard Henderson <rth@twiddle.net>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Use the standard magic.h for btrfs and squashfs.
Signed-off-by: Qinghuang Feng <qhfeng.kernel@gmail.com>
Cc: Phillip Lougher <phillip@lougher.demon.co.uk>
Cc: Chris Mason <chris.mason@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix __request_region() parameter kernel-doc notation and parameter name:
Warning(linux-2.6.28-git10//kernel/resource.c:627): No description found for parameter 'flags'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Fix jbd header file kernel-doc notation:
Warning(linux-2.6.28-git13//include/linux/jbd.h:823): No description found for parameter 'j_average_commit_time'
Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Introduce a new avg_wakeup statistic.
avg_wakeup is a measure of how frequently a task wakes up other tasks, it
represents the average time between wakeups, with a limit of avg_runtime
for when it doesn't wake up anybody.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This adds an init_dummy_netdev() function that gets a network device
structure (allocation and lifetime entirely under caller's control) and
initialize the minimum amount of fields so it can be used to schedule
NAPI polls without registering a full blown interface. This is to be
used by drivers that need to tie several hardware interfaces to a single
NAPI poll scheduler due to HW limitations.
It also updates the ibm_newemac driver to use that, this fixing the
oops on 2.6.29 due to passing NULL as "dev" to netif_napi_add()
Symbol is exported GPL only a I don't think we want binary drivers doing
that sort of acrobatics (if we want them at all).
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Tested-by: Geert Uytterhoeven <Geert.Uytterhoeven@sonycom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc: (29 commits)
powerpc/83xx: Move mcu_mpc8349emitx driver out of drivers/i2c/chips/
powerpc/83xx: Make serial ports work on MPC8315E-RDB w/ FSL U-Boots
powerpc/e500mc: Doorbells need to be taken w/exceptions disabled
powerpc: Enable PS3 options and QPACE in ppc64_defconfig
powerpc/powermac: Fix occasional SMP boot failure
powerpc/cacheinfo: Rename cache_dir per-cpu variable
hvc_console: Use kzalloc() instead of kmalloc() + memset()
hvc_console: Do not set low_latency when using interrupts
hvc_console: Call free_irq() only if request_irq() was successful
hvc_console: Change an mb() to smp_mb() and add some comments
powerpc: Cleanup from l64 to ll64 change: drivers/net
powerpc: Cleanup from l64 to ll64 change: drivers/char
powerpc: Cleanup from l64 to ll64 change: arch code
powerpc: Change u64/s64 to a long long integer type
powerpc/kexec: Check crash_base for relocatable kernel
powerpc: Make dummy section a valid note header
Xilinx: SPI: updated driver for device tree
drivers/of: Add the of_find_i2c_device_by_node function.
powerpc/xsysace: add compatible string for non-ipcore instance
powerpc/mpc52xx: remove dead code from GPIO driver
...
* 'syscalls' of git://git390.osdl.marist.edu/pub/scm/linux-2.6: (44 commits)
[CVE-2009-0029] s390 specific system call wrappers
[CVE-2009-0029] System call wrappers part 33
[CVE-2009-0029] System call wrappers part 32
[CVE-2009-0029] System call wrappers part 31
[CVE-2009-0029] System call wrappers part 30
[CVE-2009-0029] System call wrappers part 29
[CVE-2009-0029] System call wrappers part 28
[CVE-2009-0029] System call wrappers part 27
[CVE-2009-0029] System call wrappers part 26
[CVE-2009-0029] System call wrappers part 25
[CVE-2009-0029] System call wrappers part 24
[CVE-2009-0029] System call wrappers part 23
[CVE-2009-0029] System call wrappers part 22
[CVE-2009-0029] System call wrappers part 21
[CVE-2009-0029] System call wrappers part 20
[CVE-2009-0029] System call wrappers part 19
[CVE-2009-0029] System call wrappers part 18
[CVE-2009-0029] System call wrappers part 17
[CVE-2009-0029] System call wrappers part 16
[CVE-2009-0029] System call wrappers part 15
...
Add swab.h to kbuild.asm and remove the individual entries from
each arch, mark as unifdef as some arches have some kernel-only
bits inside.
Signed-off-by: Harvey Harrison <harvey.harrison@gmail.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/bart/ide-2.6:
IDE: fix sparse signed-ness errors with host->host_busy
ide: fix suspend regression
tx4938ide: Fix build error due to read_sff_dma_status moving
ide: remove unused CONFIG_BLK_DEV_IDE_AU1XXX_SEQTS_PER_RQ
sl82c105: remove dead code
via82cxxx: fix cable warning message
ide: can't use SSD/non-rotational queue flag for all CFA devices
it821x.c: use dev->revision instead of pci_read_config_byte
it821x: Add ultra_mask quirk for Vortex86SX
ide: fix accidental LOCKDEP breakage caused by local_irq_set() removal
The host_busy field in struct ide_host defaults to a
signed-long, where most arch's test_and_set_bit_*
macros use an unsigned long.
Change to using an unsigned long, which on ARM removes
the following sparse errors:
drivers/ide/ide-io.c:681:8: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:681:8: expected unsigned long volatile *p
drivers/ide/ide-io.c:681:8: got long volatile *<noident>
drivers/ide/ide-io.c:681:8: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:681:8: expected unsigned long volatile *p
drivers/ide/ide-io.c:681:8: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
drivers/ide/ide-io.c:695:3: warning: incorrect type in argument 2 (different signedness)
drivers/ide/ide-io.c:695:3: expected unsigned long volatile *p
drivers/ide/ide-io.c:695:3: got long volatile *<noident>
Signed-off-by: Ben Dooks <ben-linux@fluff.org>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
On Vortex86SX with IDE controller revision 0x11 ultra DMA must be
disabled. This patch was tested by DMP and seems to work.
It is a cleaned up version of their older Kernel patch:
http://www.dmp.com.tw/tech/vortex86sx/patch-2.6.24-DMP.gz
Tested-by: Shawn Lin <shawn@dmp.com.tw>
Signed-off-by: Brandon Philips <bphilips@suse.de>
Cc: Alan Cox <alan@lxorguk.ukuu.org.uk>
Signed-off-by: Bartlomiej Zolnierkiewicz <bzolnier@gmail.com>
Change mutex contention behaviour such that it will sometimes busy wait on
acquisition - moving its behaviour closer to that of spinlocks.
This concept got ported to mainline from the -rt tree, where it was originally
implemented for rtmutexes by Steven Rostedt, based on work by Gregory Haskins.
Testing with Ingo's test-mutex application (http://lkml.org/lkml/2006/1/8/50)
gave a 345% boost for VFS scalability on my testbox:
# ./test-mutex-shm V 16 10 | grep "^avg ops"
avg ops/sec: 296604
# ./test-mutex-shm V 16 10 | grep "^avg ops"
avg ops/sec: 85870
The key criteria for the busy wait is that the lock owner has to be running on
a (different) cpu. The idea is that as long as the owner is running, there is a
fair chance it'll release the lock soon, and thus we'll be better off spinning
instead of blocking/scheduling.
Since regular mutexes (as opposed to rtmutexes) do not atomically track the
owner, we add the owner in a non-atomic fashion and deal with the races in
the slowpath.
Furthermore, to ease the testing of the performance impact of this new code,
there is means to disable this behaviour runtime (without having to reboot
the system), when scheduler debugging is enabled (CONFIG_SCHED_DEBUG=y),
by issuing the following command:
# echo NO_OWNER_SPIN > /debug/sched_features
This command re-enables spinning again (this is also the default):
# echo OWNER_SPIN > /debug/sched_features
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The problem is that dropping the spinlock right before schedule is a voluntary
preemption point and can cause a schedule, right after which we schedule again.
Fix this inefficiency by keeping preemption disabled until we schedule, do this
by explicity disabling preemption and providing a schedule() variant that
assumes preemption is already disabled.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This assertion is incorrect for lockless pagecache. By definition if we
have an unpinned page that we are trying to take a speculative reference
to, it may become the tail of a compound page at any time (if it is
freed, then reallocated as a compound page).
It was still a valid assertion for the vmscan.c LRU isolation case, but
it doesn't seem incredibly helpful... if somebody wants it, they can
put it back directly where it applies in the vmscan code.
Signed-off-by: Nick Piggin <npiggin@suse.de>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
This enables the use of syscall wrappers to do proper sign extension
for 64-bit programs.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
By selecting HAVE_SYSCALL_WRAPPERS architectures can activate
system call wrappers in order to sign extend system call arguments.
All architectures where the ABI defines that the caller of a function
has to perform sign extension probably need this.
Reported-by: Christian Borntraeger <borntraeger@de.ibm.com>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Convert all system calls to return a long. This should be a NOP since all
converted types should have the same size anyway.
With the exception of sys_exit_group which returned void. But that doesn't
matter since the system call doesn't return.
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Impact: new tracer
The workqueue tracer provides some statistical informations
about each cpu workqueue thread such as the number of the
works inserted and executed since their creation. It can help
to evaluate the amount of work each of them have to perform.
For example it can help a developer to decide whether he should
choose a per cpu workqueue instead of a singlethreaded one.
It only traces statistical informations for now but it will probably later
provide event tracing too.
Such a tracer could help too, and be improved, to help rt priority sorted
workqueue development.
To have a snapshot of the workqueues state at any time, just do
cat /debugfs/tracing/trace_stat/workqueues
Ie:
1 125 125 reiserfs/1
1 0 0 scsi_tgtd/1
1 0 0 aio/1
1 0 0 ata/1
1 114 114 kblockd/1
1 0 0 kintegrityd/1
1 2147 2147 events/1
0 0 0 kpsmoused
0 105 105 reiserfs/0
0 0 0 scsi_tgtd/0
0 0 0 aio/0
0 0 0 ata_aux
0 0 0 ata/0
0 0 0 cqueue
0 0 0 kacpi_notify
0 0 0 kacpid
0 149 149 kblockd/0
0 0 0 kintegrityd/0
0 1000 1000 khelper
0 2270 2270 events/0
Changes in V2:
_ Drop the static array based on NR_CPU and dynamically allocate the stat array
with num_possible_cpus() and other cpu mask facilities....
_ Trace workqueue insertion at a bit lower level (insert_work instead of queue_work) to handle
even the workqueue barriers.
Signed-off-by: Frederic Weisbecker <fweisbec@gmail.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Define FTRACE_ADDR. In IA64, a function pointer isn't a 'unsigned long' but a
'struct {unsigned long ip, unsigned long gp}'.
Signed-off-by: Shaohua Li <shaohua.li@intel.com>
Signed-off-by: Steven Rostedt <srostedt@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
At run-time, if softlockup_thresh is changed to a much lower value,
touch_timestamp is likely to be much older than the new softlock_thresh.
This will cause a false softlockup to be detected. If softlockup_panic
is enabled, the system will panic.
The fix is to touch all watchdogs before changing softlockup_thresh.
Signed-off-by: Mandeep Singh Baines <msb@google.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: New perf_counter features
A pinned counter group is one that the user wants to have on the CPU
whenever possible, i.e. whenever the associated task is running, for
a per-task group, or always for a per-cpu group. If the system
cannot satisfy that, it puts the group into an error state where
it is not scheduled any more and reads from it return EOF (i.e. 0
bytes read). The group can be released from error state and made
readable again using prctl(PR_TASK_PERF_COUNTERS_ENABLE). When we
have finer-grained enable/disable controls on counters we'll be able
to reset the error state on individual groups.
An exclusive group is one that the user wants to be the only group
using the CPU performance monitor hardware whenever it is on. The
counter group scheduler will not schedule an exclusive group if there
are already other groups on the CPU and will not schedule other groups
onto the CPU if there is an exclusive group scheduled (that statement
does not apply to groups containing only software counters, which can
always go on and which do not prevent an exclusive group from going on).
With an exclusive group, we will be able to let users program PMU
registers at a low level without the concern that those settings will
perturb other measurements.
Along the way this reorganizes things a little:
- is_software_counter() is moved to perf_counter.h.
- cpuctx->active_oncpu now records the number of hardware counters on
the CPU, i.e. it now excludes software counters. Nothing was reading
cpuctx->active_oncpu before, so this change is harmless.
- A new cpuctx->exclusive field records whether we currently have an
exclusive group on the CPU.
- counter_sched_out moves higher up in perf_counter.c and gets called
from __perf_counter_remove_from_context and __perf_counter_exit_task,
where we used to have essentially the same code.
- __perf_counter_sched_in now goes through the counter list twice, doing
the pinned counters in the first loop and the non-pinned counters in
the second loop, in order to give the pinned counters the best chance
to be scheduled in.
Note that only a group leader can be exclusive or pinned, and that
attribute applies to the whole group. This avoids some awkwardness in
some corner cases (e.g. where a group leader is closed and the other
group members get added to the context list). If we want to relax that
restriction later, we can, and it is easier to relax a restriction than
to apply a new one.
This doesn't yet handle the case where a pinned counter is inherited
and goes into error state in the child - the error state is not
propagated up to the parent when the child exits, and arguably it
should.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Impact: cleanup
Change the protection parameter for track_pfn_vma_new() into a pgprot_t pointer.
Subsequent patch changes the x86 PAT handling to return a compatible
memtype in pgprot_t, if what was requested cannot be allowed due to conflicts.
No fuctionality change in this patch.
Signed-off-by: Venkatesh Pallipadi <venkatesh.pallipadi@intel.com>
Signed-off-by: Suresh Siddha <suresh.b.siddha@intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Impact: reduce kernel image size
Hugh Dickins noticed that older gcc versions when the kernel
is built for code size didn't inline some of the bitops.
Mark all complex x86 bitops that have more than a single
asm statement or two as always inline to avoid this problem.
Probably should be done for other architectures too.
Ingo then found a better fix that only requires
a single line change, but it unfortunately only
works on gcc 4.3.
On older gccs the original patch still makes a ~0.3% defconfig
difference with CONFIG_OPTIMIZE_INLINING=y.
With gcc 4.1 and a defconfig like build:
6116998 1138540 883788 8139326 7c323e vmlinux-oi-with-patch
6137043 1138540 883788 8159371 7c808b vmlinux-optimize-inlining
~20k / 0.3% difference.
Signed-off-by: Andi Kleen <ak@linux.intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
virt_to_page() call should not be used on kernel text and data
addresses. virt_to_page() is used by sg_init_one(). So change padbuf
to be allocated within iscsi_segment.
Signed-off-by: Karen Xie <kxie@chelsio.com>
Acked-by: Mike Christie <michaelc@cs.wisc.edu>
Signed-off-by: James Bottomley <James.Bottomley@HansenPartnership.com>
reorder struct xt_match to remove 8 bytes of padding and make its size
128 bytes.
This saves a small amount of data space in each of the xt netfilter
modules and fits xt_match in one 128 byte cache line.
Signed-off-by: Richard Kennedy <richard@rsk.demon.co.uk>
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
