The generic semaphore rewrite had a huge performance regression on AIM7
(and potentially other BKL-heavy benchmarks) because the generic
semaphores had been rewritten to be simple to understand and fair. The
latter, in particular, turns a semaphore-based BKL implementation into a
mess of scheduling.
The attempt to fix the performance regression failed miserably (see the
previous commit 00b41ec261 'Revert
"semaphore: fix"'), and so for now the simple and sane approach is to
instead just go back to the old spinlock-based BKL implementation that
never had any issues like this.
This patch also has the advantage of being reported to fix the
regression completely according to Yanmin Zhang, unlike the semaphore
hack which still left a couple percentage point regression.
As a spinlock, the BKL obviously has the potential to be a latency
issue, but it's not really any different from any other spinlock in that
respect. We do want to get rid of the BKL asap, but that has been the
plan for several years.
These days, the biggest users are in the tty layer (open/release in
particular) and Alan holds out some hope:
"tty release is probably a few months away from getting cured - I'm
afraid it will almost certainly be the very last user of the BKL in
tty to get fixed as it depends on everything else being sanely locked."
so while we're not there yet, we do have a plan of action.
Tested-by: Yanmin Zhang <yanmin_zhang@linux.intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Andi Kleen <andi@firstfloor.org>
Cc: Matthew Wilcox <matthew@wil.cx>
Cc: Alexander Viro <viro@ftp.linux.org.uk>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
It actually makes much more sense there, and we do tend to need it for
non-RCU usage too. Moving it to <linux/compiler.h> will allow some
other cases that have open-coded the same logic to use the same helper
function that RCU has used.
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/cooloney/blackfin-2.6: (21 commits)
Blackfin Serial Driver: abstract away DLAB differences into header
Blackfin Serial Driver: macro away the IER differences between processors
[Blackfin] arch: remove useless IRQ_SW_INT defines
[Blackfin] arch: protect linux/usb/musb.h include until the driver gets mainlined
[Blackfin] arch: protect linux/usb/isp1362.h include until the driver gets mainlined
[Blackfin] arch: add EBIU supporting for BF54x EZKIT SMSC LAN911x/LAN921x families embedded ethernet driver
[Blackfin] arch: Set spi flash partition on bf527 as like bf548.
[Blackfin] arch: fix bug - Remove module will not free L1 memory used
[Blackfin] arch: fix wrong header name in comment
[Blackfin] arch: Fix BUG - spi flash on bf527 ezkit would fail at mount
[Blackfin] arch: add twi_lcd and twi_keypad i2c board info to bf527-ezkit
[Blackfin] arch: Add physmap partition for BF527-EZkit
[Blackfin] arch: fix gdb testing regression
[Blackfin] arch: disable single stepping when delivering a signal
[Blackfin] arch: Delete unused (copied from m68k) entries in asm-offsets.c.
[Blackfin] arch: In the double fault handler, set up the PT_RETI slot
[Blackfin] arch: Support for CPU_FREQ and NOHZ
[Blackfin] arch: Functional power management support: Add CPU and platform voltage scaling support
[Blackfin] arch: fix bug - breaking the atomic sections code.
[Blackfin] arch: Equalize include files: Add VR_CTL masks
...
* git://git.kernel.org/pub/scm/linux/kernel/git/lethal/sh-2.6: (37 commits)
SH: catch negative denormal_subf1() retval in denormal_add()
sh: Fix DMAC base address for SH7709S
sh: update smc91x platform data for se7206.
sh: Stub in cpu_to_node() and friends for NUMA build.
sh: intc register modify fix
sh: no high level trigger on some sh3 cpus
sh: clean up sh7710 and sh7720 intc tables
sh: add interrupt ack code to sh3
sh: unify external irq pin code for sh3
sh-sci: avoid writing to nonexistent registers
sh-sci: sh7722 lacks scsptr registers
sh-sci: improve sh7722 support
sh: reset hardware from early printk
sh: drain and wait for early printk
sh: use sci_out() for early printk
sh: add memory resources to /proc/iomem
sh: add kernel bss resource
sh: fix sh7705 interrupt vector typo
sh: update smc91x platform data for se7722
sh: update smc91x platform data for MigoR
...
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/paulus/powerpc: (23 commits)
[POWERPC] Remove leftover printk in isa-bridge.c
[POWERPC] Remove duplicate #include
[POWERPC] Initialize lockdep earlier
[POWERPC] Document when printk is useable
[POWERPC] Fix bogus paca->_current initialization
[POWERPC] Fix of_i2c include for module compilation
[POWERPC] Make default cputable entries reflect selected CPU family
[POWERPC] spufs: lockdep annotations for spufs_dir_close
[POWERPC] spufs: don't requeue victim contex in find_victim if it's not in spu_run
[POWERPC] 4xx: Fix PCI mem in sequoia DTS
[POWERPC] 4xx: Add endpoint support to 4xx PCIe driver
[POWERPC] 4xx: Fix problem with new TLB storage attibute fields on 440x6 core
[POWERPC] spufs: spu_create should send inotify IM_CREATE event
[POWERPC] spufs: handle faults while the context switch pending flag is set
[POWERPC] spufs: fix concurrent delivery of class 0 & 1 exceptions
[POWERPC] spufs: try to route SPU interrupts to local node
[POWERPC] spufs: set SPU_CONTEXT_SWITCH_PENDING before synchronising SPU irqs
[POWERPC] spufs: don't acquire state_mutex interruptible while performing callback
[POWERPC] spufs: update master runcntl with context lock held
[POWERPC] spufs: fix post-stopped update of MFC_CNTL register
...
Don't allow a module built without versions altogether to be inserted
into a kernel which expects modversions.
modprobe --force will strip vermagic as well as modversions, so it
won't be effected, but this will make sure that a
non-CONFIG_MODVERSIONS module won't be accidentally inserted into a
CONFIG_MODVERSIONS kernel.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Remove #ifdef CONFIG_OF_I2C as this breaks module compilation.
Drivers using this header should depend on OF_I2C anyways, so
there's no need to make this conditional.
Signed-off-by: Jochen Friedrich <jochen@scram.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On SH7709S, DMAC can be found at 0xa4000020 (as with most of
the other sh3 cpu subtypes).
Split out definition of DMAC base address from definitions of
DMTE irqs.
Signed-off-by: Steve Glendinning <steve.glendinning@smsc.com>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6: (32 commits)
net: Added ASSERT_RTNL() to dev_open() and dev_close().
can: Fix can_send() handling on dev_queue_xmit() failures
netns: Fix arbitrary net_device-s corruptions on net_ns stop.
netfilter: Kconfig: default DCCP/SCTP conntrack support to the protocol config values
netfilter: nf_conntrack_sip: restrict RTP expect flushing on error to last request
macvlan: Fix memleak on device removal/crash on module removal
net/ipv4: correct RFC 1122 section reference in comment
tcp FRTO: SACK variant is errorneously used with NewReno
e1000e: don't return half-read eeprom on error
ucc_geth: Don't use RX clock as TX clock.
cxgb3: Use CAP_SYS_RAWIO for firmware
pcnet32: delete non NAPI code from driver.
fs_enet: Fix a memory leak in fs_enet_mdio_probe
[netdrvr] eexpress: IPv6 fails - multicast problems
3c59x: use netstats in net_device structure
3c980-TX needs EXTRA_PREAMBLE
fix warning in drivers/net/appletalk/cops.c
e1000e: Add support for BM PHYs on ICH9
uli526x: fix endianness issues in the setup frame
uli526x: initialize the hardware prior to requesting interrupts
...
Make cpu_relax() invoke barrier() to be the same as other arches.
Signed-off-by: David Howells <dhowells@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'for-linus' of git://git.kernel.dk/linux-2.6-block:
Revert "relay: fix splice problem"
docbook: fix bio missing parameter
block: use unitialized_var() in bio_alloc_bioset()
block: avoid duplicate calls to get_part() in disk stat code
cfq-iosched: make io priorities inherit CPU scheduling class as well as nice
block: optimize generic_unplug_device()
block: get rid of likely/unlikely predictions in merge logic
vfs: splice remove_suid() cleanup
cfq-iosched: fix RCU race in the cfq io_context destructor handling
block: adjust tagging function queue bit locking
block: sysfs store function needs to grab queue_lock and use queue_flag_*()
* 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jack/linux-udf-2.6:
udf: Fix memory corruption when fs mounted with noadinicb option
udf: Make udf exportable
udf: fs/udf/partition.c:udf_get_pblock() mustn't be inline
Some Inovaphone PBXs exhibit very stange behaviour: when dialing for
example "123", the device sends INVITE requests for "1", "12" and
"123" back to back. The first requests will elicit error responses
from the receiver, causing the SIP helper to flush the RTP
expectations even though we might still see a positive response.
Note the sequence number of the last INVITE request that contained a
media description and only flush the expectations when receiving a
negative response for that sequence number.
Signed-off-by: Patrick McHardy <kaber@trash.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
This patch adds interrupt acknowledge code for external interrupt
sources on sh3 processors. Only really required for edge triggered
interrupts, but we ack regardless of sense configuration.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
This patch unifies the sh3 external irq pin code. It buys us some
savings with reduced code redundancy, but the main feature with
this change is irq sense selection support for all sh3 processors.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
Add physical memory resources such as System RAM, Kernel code/data/bss
and reserved crash dump area to /proc/iomem. Same strategy as on x86.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
SH_MPC1211 has been marked as BROKEN for some time.
Unless someone is working on reviving it now, I'd therefore suggest this
patch to remove it.
Signed-off-by: Adrian Bunk <bunk@kernel.org>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>
get_part() is fairly expensive, as it O(N) loops over partitions
to find the right one. In lots of normal IO paths we end up looking
up the partition twice, to make matters even worse. Change the
stat add code to accept a passed in partition instead.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
We currently set all processes to the best-effort scheduling class,
regardless of what CPU scheduling class they belong to. Improve that
so that we correctly track idle and rt scheduling classes as well.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
generic_file_splice_write() duplicates remove_suid() just because it
doesn't hold i_mutex. But it grabs i_mutex inside splice_from_pipe()
anyway, so this is rather pointless.
Move locking to generic_file_splice_write() and call remove_suid() and
__splice_from_pipe() instead.
Signed-off-by: Miklos Szeredi <mszeredi@suse.cz>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
Use the existing arch_alloc_page/arch_free_page callbacks to do
the guest page state transitions between stable and unused.
Acked-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This removes redundant arch code for generic ptrace requests
already handled by ptrace_request and compat_ptrace_request.
It simplifies things to just have the standard entry points,
and use the generic compat_sys_ptrace.
Signed-off-by: Roland McGrath <roland@redhat.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
From: Martin Schwidefsky <schwidefsky@de.ibm.com>
This patch fixes a bug with cpu bound guest on kvm-s390. Sometimes it
was impossible to deliver a signal to a spinning guest. We used
preemption as a circumvention. The preemption notifiers called
vcpu_load, which checked for pending signals and triggered a host
intercept. But even with preemption, a sigkill was not delivered
immediately.
This patch changes the low level host interrupt handler to check for the
SIE instruction, if TIF_WORK is set. In that case we change the
instruction pointer of the return PSW to rerun the vcpu_run loop. The kvm
code sees an intercept reason 0 if that happens. This patch adds accounting
for these types of intercept as well.
The advantages:
- works with and without preemption
- signals are delivered immediately
- much better host latencies without preemption
Acked-by: Carsten Otte <cotte@de.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
When transferring to IRQ5 from an exception, save SYSCFG in memory across the
transfer and clear the trace bit.
When we get a single step exception, check whether we can safely clear the
trace bit in SYSCFG. We can (and should) clear it after the first instruction
of the interrupt handler; the first insn saves SYSCFG to the stack in all
handlers.
Signed-off-by: Bernd Schmidt <bernds_cb1@t-online.de>
Signed-off-by: Bryan Wu <cooloney@kernel.org>
Fix warning from pmd_bad() at bootup on a HIGHMEM64G HIGHPTE x86_32.
That came from 9fc34113f6 x86: debug pmd_bad();
but we understand now that the typecasting was wrong for PAE in the previous
version: pagetable pages above 4GB looked bad and stopped Arjan from booting.
And revert that cded932b75 x86: fix pmd_bad
and pud_bad to support huge pages. It was the wrong way round: we shouldn't
weaken every pmd_bad and pud_bad check to let huge pages slip through - in
part they check that we _don't_ have a huge page where it's not expected.
Put the x86 pmd_bad() and pud_bad() definitions back to what they have long
been: they can be improved (x86_32 should use PTE_MASK, to stop PAE thinking
junk in the upper word is good; and x86_64 should follow x86_32's stricter
comparison, to stop thinking any subset of required bits is good); but that
should be a later patch.
Fix Hans' good observation that follow_page() will never find pmd_huge()
because that would have already failed the pmd_bad test: test pmd_huge in
between the pmd_none and pmd_bad tests. Tighten x86's pmd_huge() check?
No, once it's a hugepage entry, it can get quite far from a good pmd: for
example, PROT_NONE leaves it with only ACCESSED of the KERN_PGTABLE bits.
However... though follow_page() contains this and another test for huge
pages, so it's nice to keep it working on them, where does it actually get
called on a huge page? get_user_pages() checks is_vm_hugetlb_page(vma) to
to call alternative hugetlb processing, as does unmap_vmas() and others.
Signed-off-by: Hugh Dickins <hugh@veritas.com>
Earlier-version-tested-by: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Jeff Chua <jeff.chua.linux@gmail.com>
Cc: Hans Rosenfeld <hans.rosenfeld@amd.com>
Cc: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
And with that last patch to affs killing the last put_inode instance we
can finally, after many years of transition kill this racy and awkward
interface.
(It's kinda funny that even the description in
Documentation/filesystems/vfs.txt was entirely wrong..)
Also remove a very misleading comment above the defintion of
struct super_operations.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* 'upstream-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jgarzik/libata-dev: (27 commits)
pata_atiixp: Don't disable
sata_inic162x: update intro comment, up the version and drop EXPERIMENTAL
sata_inic162x: add cardbus support
sata_inic162x: kill now unused SFF related stuff
sata_inic162x: use IDMA for ATAPI commands
sata_inic162x: use IDMA for non DMA ATA commands
sata_inic162x: kill now unused bmdma related stuff
sata_inic162x: use IDMA for ATA_PROT_DMA
sata_inic162x: update TF read handling
sata_inic162x: add / update constants
sata_inic162x: misc clean ups
sata_mv use hweight16() for bit counting (V2)
sata_mv NCQ-EH for FIS-based switching
sata_mv delayed eh handling
libata: export ata_eh_analyze_ncq_error
sata_mv new mv_port_intr function
sata_mv fix mv_host_intr bug for hc_irq_cause
sata_mv NCQ and SError fixes for mv_err_intr
sata_mv rearrange mv_config_fbs
sata_mv errata workaround for sata25 part 1
...
Declared some things static, declared some things in the header.
Signed-off-by: Andy Fleming <afleming@freescale.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
Export ata_eh_analyze_ncq_error() for subsequent use by sata_mv,
as suggested by Tejun.
Signed-off-by: Mark Lord <mlord@pobox.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
The new 440x6 core used on AMCC 460EX/GT introduces new storage attibure
fields to the TLB2 word. Those are:
Bit 11 12 13 14 15
WL1 IL1I IL1D IL2I IL2D
With these bits the cache (L1 and L2) can be configured in a more flexible
way, instruction- and data-cache independently now. The "old" I and W bits
are still available and setting these old bits will automically set these
new bits too (for backward compatibilty).
The current code does not clear these fields resulting in disabling the cache
by chance. This patch now makes sure that these new bits are cleared when
the TLB2 word is written.
Signed-off-by: Stefan Roese <sr@denx.de>
Signed-off-by: Josh Boyer <jwboyer@linux.vnet.ibm.com>
Some controllers (jmb and inic162x) use 0x77 and 0x7f to indicate that
the device isn't ready yet. It looks like they use 0xff if device
presence is detected but connection isn't established. 0x77 or 0x7f
after connection is established and use the value from signature FIS
after receiving it.
This patch implements ata_check_ready(), which takes TF status value
and determines whether the port is ready or not considering the above
and other conditions, and use it in @check_ready() functions. This is
safe as both 0x77 and 0x7f aren't valid ready status value even though
they have BSY bit cleared.
This fixes hot plug detection failures which can be triggered with
certain drives if they aren't already spun up when the data connector
is hot plugged.
Tested on sil, sil24, ahci (jmb/ich), piix and inic162x combined with
eight drives from all major vendors.
Signed-off-by: Tejun Heo <htejun@gmail.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-2.6:
net_cls_act: act_simple dont ignore realloc code
iwlwifi: make IWLWIFI a tristate
Revert "atm: Do not free already unregistered net device."
dccp: return -EINVAL on invalid feature length
irda: fix !PNP support for drivers/net/irda/smsc-ircc2.c
irda: fix !PNP support in drivers/net/irda/nsc-ircc.c
net_cls_act: Make act_simple use of netlink policy.
ip: Use inline function dst_metric() instead of direct access to dst->metric[]
ip: Make use of the inline function dst_metric_locked()
atm: Bad locking on br2684_devs modifications.
atm: Do not free already unregistered net device.
mac80211: Do not free net device after it is unregistered.
bridge: Consolidate error paths in br_add_bridge().
bridge: Net device leak in br_add_bridge().
niu: Fix probing regression for maramba on-board chips.
lapbeth: Release ->ethdev when unregistering device.
xfrm: convert empty xfrm_audit_* macros to functions
net: Fix useless comment reference loop.
sch_htb: remove from event queue in htb_parent_to_leaf()
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mingo/linux-2.6-sched-fixes:
sched: default to n for GROUP_SCHED and FAIR_GROUP_SCHED
sched: add optional support for CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
sched, x86: add HAVE_UNSTABLE_SCHED_CLOCK
sched: fix cpu clock
sched: fair-group: fix a Div0 error of the fair group scheduler
sched: fix missing locking in sched_domains code
sched: make clock sync tunable by architecture code
sched: fix debugging
sched: fix sched_info_switch not being called according to documentation
sched: fix hrtick_start_fair and CPU-Hotplug
sched: fix SCHED_FAIR wake-idle logic error
sched: fix RT task-wakeup logic
sched: add statics, don't return void expressions
sched: add debug checks to idle functions
sched: remove old sched doc
sched: make rt_sched_class, idle_sched_class static
sched: optimize calc_delta_mine()
sched: fix normalized sleeper
this replaces the rq->clock stuff (and possibly cpu_clock()).
- architectures that have an 'imperfect' hardware clock can set
CONFIG_HAVE_UNSTABLE_SCHED_CLOCK
- the 'jiffie' window might be superfulous when we update tick_gtod
before the __update_sched_clock() call in sched_clock_tick()
- cpu_clock() might be implemented as:
sched_clock_cpu(smp_processor_id())
if the accuracy proves good enough - how far can TSC drift in a
single jiffie when considering the filtering and idle hooks?
[ mingo@elte.hu: various fixes and cleanups ]
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
