This is the MFD driver for the DaVinci Voice codec, it has two clients:
* Voice codec interface
* Voice codec CQ93VC
Signed-off-by: Miguel Aguilar <miguel.aguilar@ridgerun.com>
Acked-by: Samuel Ortiz <sameo@linux.intel.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
For ASoC, if either CPU or CODEC driver has set the flag, the MACHINE driver
should be given a chance to figure out if the dai, that set the flag, can
accomodate a rate that it does not explicitly specify but is specified
by the dai at the other end of the link.
Signed-off-by: Jassi Brar <jassi.brar@samsung.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Newt has widespread availability and provides a rather simple
API as can be seen by the size of this patch.
The work needed to support it will benefit other frontends too.
In this initial patch it just checks if the output is a tty, if
not it falls back to the previous behaviour, also if
newt-devel/libnewt-dev is not installed the previous behaviour
is maintaned.
Pressing enter on a symbol will annotate it, ESC in the
annotation window will return to the report symbol list.
More work will be done to remove the special casing in
color_fprintf, stop using fmemopen/FILE in the printing of
hist_entries, etc.
Also the annotation doesn't need to be done via spawning "perf
annotate" and then browsing its output, we can do better by
calling directly the builtin-annotate.c functions, that would
then be moved to tools/perf/util/annotate.c and shared with perf
top, etc
But lets go by baby steps, this patch already improves perf
usability by allowing to quickly do annotations on symbols from
the report screen and provides a first experimentation with
libnewt/TUI integration of tools.
Tested on RHEL5 and Fedora12 X86_64 and on Debian PARISC64 to
browse a perf.data file collected on a Fedora12 x86_64 box.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1268349164-5822-5-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
We need those to properly size the browser widht in the newt
TUI.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1268349164-5822-4-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Just like we do for pr_debug, so that we can have a single point
where to redirect to the currently used output system, be it
stdio or newt.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1268349164-5822-3-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Will be used by the newt code too.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
LKML-Reference: <1268349164-5822-2-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
target_cpu() should initially target all cpus, not just cpu 0.
Otherwise systems with lots of disks can exhaust the interrupt
vectors on cpu 0 if a large number of disks are discovered
before the irq balancer is running.
Note: UV code only...
Signed-off-by: Jack Steiner <steiner@sgi.com>
LKML-Reference: <20100311184328.GA21433@sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In case of not assigned x86_pmu and software events NULL dereference may
being hit via x86_pmu::schedule_events method.
Fix it by checking if x86_pmu is initialized at all.
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Cc: Lin Ming <ming.m.lin@intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
LKML-Reference: <20100311215016.GG25162@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Do not pin/unpin superblock for every inode in writeback_inodes_wb(), pin
it for the whole group of inodes which belong to the same superblock and
call writeback_sb_inodes() handler for them.
Signed-off-by: Edward Shishkin <edward.shishkin@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Cc: Wu Fengguang <fengguang.wu@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
With `while (j++ < PX_SPIN)' j reaches PX_SPIN + 1 after the loop. This
is probably unlikely to produce a problem.
Signed-off-by: Roel Kluin <roel.kluin@gmail.com>
Cc: Jens Axboe <jens.axboe@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
commit 5fb4d38b19 ("mfd: Move WM831x to
generic IRQ") didn't take into account that genirq support depends on
GENERIC_HARDIRQS.
Additionally, 2.6.34-rc1 added:
- commit 2afa62ea76 ("mfd: Use genirq in
88pm860x").
- commit 760e451878 ("mfd: Convert WM8350 to
genirq").
- commit 1f1cf8f98c ("mfd: Update irq handler
in max8925")
Make all of them depend on GENERIC_HARDIRQS to avoid compile errors on
architectures that don't support genirq yet.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
We should only request for the MFD used region, not the whole thing.
Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
Tested-by: Paul Mundt <lethal@linux-sh.org>
Reviewed-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Some network devices, particularly USB ones, take several seconds to
fully init and appear in the device list.
If the user turned ipconfig on, they are using it for NFS root or some
other early booting purpose. So it makes no sense to just flat out
fail immediately if the device isn't found.
It also doesn't make sense to just jack up the initial wait to
something crazy like 10 seconds.
Instead, poll immediately, and then periodically once a second,
waiting for a usable device to appear. Fail after 12 seconds.
Signed-off-by: David S. Miller <davem@davemloft.net>
Tested-by: Christian Pellegrin <chripell@fsfe.org>
When building for multi-omap, and OMAP4 is enabled, CONFIG_ARCH_OMAP4
will be true and prevent included code from building/running for
OMAP2/3 as well.
This problem exists in io.c where some hwmod/PM/SDRC init code is
prevented from running even on OMAP2/3 when OMAP4 is included in a
multi-OMAP build.
A quick glance suggests that this #ifndef is no longer needed in most
of the cases. In the remaining cases, the function is wrapped with
"if (cpu_is_omap24xx() || cpu_is_omap34xx())" which will be optimized
out for OMAP4-only builds.
Note that this is only a short-term fix. Longer-term, OMAP4
needs to create init functions for SDRC and hwmod late-init.
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Currently if omap2420 is defined but not omap2430, cpu_is_omap2430()
is still defined as a macro, instead of #define'd to zero. This
results in conditional cpu_is_omap2430() code still being compiled,
and leads to possible compile/link errors. In particular for hwmod
init.
To fix, add extra #ifdefs to CPU check macros to ensure that the
is_omap* macros are zero for each OMAP2 if they are not configured
into the kernel.
Tested-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Get rid of the following warnings:
warning: non-ANSI function declaration of function [...]
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Clear the stall bit to drop any incoming packets while destroying NIC
QP. This will prevent a chip resource leak.
Signed-off-by: Chien Tung <chien.tin.tung@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Set assume_aligned_header bit in QP context as requested by hardware group.
Signed-off-by: Faisal Latif <faisal.latif@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
For omap4 case, this was wrongly writing GPIO_LEVELDETECTx
registers with OMAP24XX_ offset and OMAP4_ offset.
Bug introduced in commit:
commit 3f1686a9bf
Author: Tony Lindgren <tony@atomide.com>
Date: Mon Feb 15 09:27:25 2010 -0800
omap: Fix gpio.c for multi-omap for omap4
Signed-off-by: Sergio Aguirre <saaguirre@ti.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
Select CONFIG_LEDS_GPIO to enable IGEP v2 LED support and control of supported
LEDs from userspace. Otherwise GPIO LEDs are exported as GPIO 26, 27 and 28 using
the gpiolib framework.
Signed-off-by: Enric Balletbo i Serra <eballetbo@iseebcn.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
arch/arm/plat-omap/include/plat/blizzard.h:9:
ERROR: spaces prohibited around that ':' (ctx:WxW)
Signed-off-by: Andrea Gelmini <andrea.gelmini@gelma.net>
Signed-off-by: Tony Lindgren <tony@atomide.com>
This patch follows the commit be093beb60
by Russell King:
OMAP wishes to pass state to the boot loader upon reboot in order
to instruct it whether to wait for USB-based reflashing or not.
There is already a facility to do this via the reboot() syscall,
except we ignore the string passed to machine_restart().
The patch adds the missing parameter to omap1_arch_reset() and
omap_prcm_arch_reset(), and modifies the latter to pass the reboot
command parameter to the boot loader instead of reboot mode (which is
for kernel internal use only and cannot be modified by the userspace).
Signed-off-by: Aaro Koskinen <aaro.koskinen@nokia.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>
The omap_serial_early_init prints the following errors:
Could not get uart4_ick
Could not get uart4_fck
because all the uarts available in omap_uart[] will be initialized.
Only omap4430 and omap3630 have 4 uarts at the moment.
This patch reduces the number of uarts when cpu is not omap4430 or
omap3630.
Signed-off-by: Thomas Weber <weber@corscience.de>
Signed-off-by: Tony Lindgren <tony@atomide.com>
During a hot-plug LLD removal event or an EEH error event, iw_cxgb3
must ensure that any/all threads that might be in a cxgb3 exported
function must return from the function before iw_cxgb3 returns from
its event processing. Do this by calling synchronize_net().
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
When an iWARP device is unloaded, the ib_mad module logs errors. It
should be ignoring iWARP devices on device removal just like it does
on device add.
Signed-off-by: Steve Wise <swise@opengridcomputing.com>
Acked-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
Print the return code of ib_post_send() if it fails to make these
debugging messages more useful.
Signed-off-by: Or Gerlitz <ogerlitz@voltaire.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
The IPoIB UD QP reports send completions to priv->send_cq, which is
usually left unarmed; it only gets armed when the number of
outstanding send requests reaches the size of the TX queue. This
arming is done only in the send path for the UD QP. However, when
sending CM packets, the net queue may be stopped for the same reasons
but no measures are taken to recover the UD path from a lockup.
Consider this scenario: a host sends high rate of both CM and UD
packets, with a TX queue length of N. If at some time the number of
outstanding UD packets is more than N/2 and the overall outstanding
packets is N-1, and CM sends a packet (making the number of
outstanding sends equal N), the TX queue will be stopped. When all
the CM packets complete, the number of outstanding packets will still
be higher than N/2 so the TX queue will not be restarted.
Fix this by calling ib_req_notify_cq() when the queue is stopped in
the CM path.
Signed-off-by: Eli Cohen <eli@mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
While waiting for the related USB patch, fix compile by enabling
it in the defconfigs. As discussed at:
http://thread.gmane.org/gmane.linux.usb.general/27432/focus=4460
Otherwise we'll get errors like:
drivers/usb/core/hcd.c:1892: error: 'pm_wq' undeclared (first use in this function)
drivers/usb/core/hcd.c:1892: error: (Each undeclared identifier is reported only once
drivers/usb/core/hcd.c:1892: error: for each function it appears in.)
Signed-off-by: Tony Lindgren <tony@atomide.com>
Fixing this symptom:
[acme@mica linux-2.6-tip]$ perf record -a -f
Fatal: Permission error - are you root?
Bus error
[acme@mica linux-2.6-tip]$
I.e. if for some reason no data is collected, in this case a non
root user trying to do systemwide profiling, no data will be
collected, and then we end up trying to mmap a zero sized file
and access the file header, b00m.
Reported-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Frédéric Weisbecker <fweisbec@gmail.com>
Cc: Mike Galbraith <efault@gmx.de>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: <stable@kernel.org>
LKML-Reference: <1268333592-30872-1-git-send-email-acme@infradead.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Recent DMA API changes broke compile for tusb6010. While
testing the fixes for tusb6010, I had to update the n8x0
defconfig quite a bit. Might as well merge it while at it
to make it more usable as we're using this to test the
multi-omap booting between V6 and V7 ARMs.
Also, anybody using n8x0 with a current kernel will most
likely want to mount root on the MMC instead of the onenand
to keep the Maemo install intact.
Enable I2C, REGULATOR, MMC, MFD, PM, and USB. Also change the root
to /dev/mmcblk0p2 instead of the onenand.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Based on Kalle's and Tony's patches. Some variables re-organized
and unused code removed.
Signed-off-by: Kalle Valo <kalle.valo@iki.fi>
Signed-off-by: Francisco Alecrim <francisco.alecrim@openbossa.org>
[tony@atomide.com: this is needed to fix the related tusb6010 DMA API changes]
Signed-off-by: Tony Lindgren <tony@atomide.com>
The netburst PMU is way different from the "architectural
perfomance monitoring" specification that current CPUs use.
P4 uses a tuple of ESCR+CCCR+COUNTER MSR registers to handle
perfomance monitoring events.
A few implementational details:
1) We need a separate x86_pmu::hw_config helper in struct
x86_pmu since register bit-fields are quite different from P6,
Core and later cpu series.
2) For the same reason is a x86_pmu::schedule_events helper
introduced.
3) hw_perf_event::config consists of packed ESCR+CCCR values.
It's allowed since in reality both registers only use a half
of their size. Of course before making a real write into a
particular MSR we need to unpack the value and extend it to
a proper size.
4) The tuple of packed ESCR+CCCR in hw_perf_event::config
doesn't describe the memory address of ESCR MSR register
so that we need to keep a mapping between these tuples
used and available ESCR (various P4 events may use same
ESCRs but not simultaneously), for this sake every active
event has a per-cpu map of hw_perf_event::idx <--> ESCR
addresses.
5) Since hw_perf_event::idx is an offset to counter/control register
we need to lift X86_PMC_MAX_GENERIC up, otherwise kernel
strips it down to 8 registers and event armed may never be turned
off (ie the bit in active_mask is set but the loop never reaches
this index to check), thanks to Peter Zijlstra
Restrictions:
- No cascaded counters support (do we ever need them?)
- No dependent events support (so PERF_COUNT_HW_INSTRUCTIONS
doesn't work for now)
- There are events with same counters which can't work simultaneously
(need to use intersected ones due to broken counter 1)
- No PERF_COUNT_HW_CACHE_ events yet
Todo:
- Implement dependent events
- Need proper hashing for event opcodes (no linear search, good for
debugging stage but not in real loads)
- Some events counted during a clock cycle -- need to set threshold
for them and count every clock cycle just to get summary statistics
(ie to behave the same way as other PMUs do)
- Need to swicth to use event_constraints
- To support RAW events we need to encode a global list of P4 events
into p4_templates
- Cache events need to be added
Event support status matrix:
Event status
-----------------------------
cycles works
cache-references works
cache-misses works
branch-misses works
bus-cycles partially (does not work on 64bit cpu with HT enabled)
instruction doesnt work (needs dependent event [mop tagging])
branches doesnt work
Signed-off-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Lin Ming <ming.m.lin@intel.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Robert Richter <robert.richter@amd.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
LKML-Reference: <20100311165439.GB5129@lenovo>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This patch moves omap_smc1 function to a seperate omap44xx-smc.S file
and sets compile flags as -Wa,-march=armv7-a.
This fix was suggested by Tony Lindgren <tony@atomide.com>
Signed-off-by: Santosh Shilimkar <santosh.shilimkar@ti.com>
[tony@atomide.com: otherwise multi-omap build with V6 and V7 breaks]
Signed-off-by: Tony Lindgren <tony@atomide.com>
Disabling affine wakeups is too horrible to contemplate. Remove the feature flag.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301890.6785.50.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This features has been enabled for quite a while, after testing showed that
easing preemption for light tasks was harmful to high priority threads.
Remove the feature flag.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301675.6785.44.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Sync wakeups are critical functionality with a long history. Remove it, we don't
need the branch or icache footprint.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301817.6785.47.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This feature never earned its keep, remove it.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301591.6785.42.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Our preemption model relies too heavily on sleeper fairness to disable it
without dire consequences. Remove the feature, and save a branch or two.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301520.6785.40.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This feature hasn't been enabled in a long time, remove effectively dead code.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301447.6785.38.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Don't bother with selection when the current cpu is idle. Recent load
balancing changes also make it no longer necessary to check wake_affine()
success before returning the selected sibling, so we now always use it.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301369.6785.36.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Allow LAST_BUDDY to kick in sooner, improving cache utilization as soon as
a second buddy pair arrives on scene. The cost is latency starting to climb
sooner, the tbenefit for tbench 8 on my Q6600 box is ~2%. No detrimental
effects noted in normal idesktop usage.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301285.6785.34.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now that we no longer depend on the clock being updated prior to enqueueing
on migratory wakeup, we can clean up a bit, placing calls to update_rq_clock()
exactly where they are needed, ie on enqueue, dequeue and schedule events.
In the case of a freshly enqueued task immediately preempting, we can skip the
update during preemption, as the clock was just updated by the enqueue event.
We also save an unneeded call during a migratory wakeup by not updating the
previous runqueue, where update_curr() won't be invoked.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301199.6785.32.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Both avg_overlap and avg_wakeup had an inherent problem in that their accuracy
was detrimentally affected by cross-cpu wakeups, this because we are missing
the necessary call to update_curr(). This can't be fixed without increasing
overhead in our already too fat fastpath.
Additionally, with recent load balancing changes making us prefer to place tasks
in an idle cache domain (which is good for compute bound loads), communicating
tasks suffer when a sync wakeup, which would enable affine placement, is turned
into a non-sync wakeup by SYNC_LESS. With one task on the runqueue, wake_affine()
rejects the affine wakeup request, leaving the unfortunate where placed, taking
frequent cache misses.
Remove it, and recover some fastpath cycles.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301121.6785.30.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Testing the load which led to this heuristic (nfs4 kbuild) shows that it has
outlived it's usefullness. With intervening load balancing changes, I cannot
see any difference with/without, so recover there fastpath cycles.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301062.6785.29.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Entering nohz code on every micro-idle is costing ~10% throughput for netperf
TCP_RR when scheduling cross-cpu. Rate limiting entry fixes this, but raises
ticks a bit. On my Q6600, an idle box goes from ~85 interrupts/sec to 128.
The higher the context switch rate, the more nohz entry costs. With this patch
and some cycle recovery patches in my tree, max cross cpu context switch rate is
improved by ~16%, a large portion of which of which is this ratelimiting.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
LKML-Reference: <1268301003.6785.28.camel@marge.simson.net>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
