Mostly PHY access and a few (ugly) debug statements for DMA control.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The firmware is cached during the first successful call to open() and
released once the network device is unregistered. The driver uses the
cached firmware between open() and unregister_netdev().
It's similar to 953a12cc28 but the
firmware is mandatory.
Signed-off-by: Francois Romieu <romieu@fr.zoreil.com>
Reviewed-by: Michael Chan <mchan@broadcom.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This repairs problem with compile library in userspace (libnl).
Signed-off-by: Jiří Župka <jzupka@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Allows ss command (iproute2) to display "ecnseen" if at least one packet
with ECT(0) or ECT(1) or ECN was received by this socket.
"ecn" means ECN was negotiated at session establishment (TCP level)
"ecnseen" means we received at least one packet with ECT fields set (IP
level)
ss -i
...
ESTAB 0 0 192.168.20.110:22 192.168.20.144:38016
ino:5950 sk:f178e400
mem:(r0,w0,f0,t0) ts sack ecn ecnseen bic wscale:7,8 rto:210
rtt:12.5/7.5 cwnd:10 send 9.3Mbps rcv_space:14480
Signed-off-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The following commit removed some including headers:
"net: sh_eth: move the asm/sh_eth.h to include/linux/"
(commit id: d4fa0e35fd)
Then, the build failure happened on the linux-next:
drivers/net/ethernet/renesas/sh_eth.c:601: error: 'THIS_MODULE' undeclared here (not in a function)
drivers/net/ethernet/renesas/sh_eth.c:1970: error: expected declaration specifiers or '...' before string constant
drivers/net/ethernet/renesas/sh_eth.c:1970: warning: data definition has no type or storage class
drivers/net/ethernet/renesas/sh_eth.c:1970: warning: type defaults to 'int' in declaration of 'MODULE_AUTHOR'
drivers/net/ethernet/renesas/sh_eth.c:1970: warning: function declaration isn't a prototype
drivers/net/ethernet/renesas/sh_eth.c:1971: error: expected declaration specifiers or '...' before string constant
drivers/net/ethernet/renesas/sh_eth.c:1971: warning: data definition has no type or storage class
drivers/net/ethernet/renesas/sh_eth.c:1971: warning: type defaults to 'int' in declaration of 'MODULE_DESCRIPTION'
drivers/net/ethernet/renesas/sh_eth.c:1971: warning: function declaration isn't a prototype
drivers/net/ethernet/renesas/sh_eth.c:1972: error: expected declaration specifiers or '...' before string constant
drivers/net/ethernet/renesas/sh_eth.c:1972: warning: data definition has no type or storage class
drivers/net/ethernet/renesas/sh_eth.c:1972: warning: type defaults to 'int' in declaration of 'MODULE_LICENSE'
drivers/net/ethernet/renesas/sh_eth.c:1972: warning: function declaration isn't a prototype
This patch fixes the issue. This patch also get back include/kernel.h
and linux/spinlock.h.
Reported-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
During a test where a pair of bonding interfaces using ARP monitoring
were both brought up and torn down (with an rmmod) repeatedly, a panic
in the timer code was noticed. I tracked this down and determined that
any of the bonding functions that ran as workqueue handlers and requeued
more work might not properly exit when the module was removed.
There was a flag protected by the bond lock called kill_timers that is
set when the interface goes down or the module is removed, but many of
the functions that monitor link status now unlock the bond lock to take
rtnl first. There is a chance that another CPU running the rmmod could
get the lock and set kill_timers after the first check has passed.
This patch does not allow any function to queue work that will make
itself run unless kill_timers is not set. I also noticed while doing
this work that bond_resend_igmp_join_requests did not have a check for
kill_timers, so I added the needed call there as well.
Signed-off-by: Andy Gospodarek <andy@greyhouse.net>
Reported-by: Liang Zheng <lzheng@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
The allocation of "phyinfo" wasn't checked, and also the allocation
wasn't freed on error paths. Sjur Brændeland pointed out as well
that "phy_driver" should be freed on the error path too.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Sjur Brændeland <sjur.brandeland@stericsson.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Apart from the obvious cleanup, this should make the line
cursor_end = x - xorigin + w;
correct now.
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Fixes cursor disappearing prematurely when moving off a top/left edge which
is not located at the desktop top/left edge.
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Cc: stable@kernel.org
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Michel Dänzer <michel.daenzer@amd.com>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
The mouse cursor hotspot calculation when the cursor is partially off the
top or left side of the screen was off by one.
Fixes https://bugs.freedesktop.org/show_bug.cgi?id=41158
Signed-off-by: Nicholas Miell <nmiell@gmail.com>
Reviewed-by: Michel Dänzer <michel@daenzer.net>
Reviewed-by: Alex Deucher <alexander.deucher@amd.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
Only disable the pipe if the monitor is physically
disconnected. The previous logic also disabled the
pipe if the link was trained.
Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=41248
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
The previous code could potentially loop forever. Limit
the number of DP aux defer retries to 4 for native aux
transactions, same as i2c over aux transactions.
Noticed by: Brad Campbell <lists2009@fnarfbargle.com>
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Brad Campbell <lists2009@fnarfbargle.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
An incorrect ordering in the error checking code lead
to DP aux defer being skipped in the aux native write
path. Move the bytes transferred check (ret == 0)
below the defer check.
Tracked down by: Brad Campbell <brad@fnarfbargle.com>
Fixes:
https://bugs.freedesktop.org/show_bug.cgi?id=41121
Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
Cc: Brad Campbell <brad@fnarfbargle.com>
Cc: stable@kernel.org
Signed-off-by: Dave Airlie <airlied@redhat.com>
Need to allow application to update existing fdb entries that already
exist. This makes bridge netlink neighbor API have same flags and
semantics as ip neighbor table.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
When port is added to a bridge, the old code would send the new neighbor
netlink message before the subsequent new link message. This bug makes
it difficult to use the monitoring API in an application.
This code changes the ordering to add the forwarding entry
after the port is setup. One of the error checks (for invalid address)
is moved earlier in the process to avoid having to do unwind.
Signed-off-by: Stephen Hemminger <shemminger@vyatta.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Also changing it's frequency to once every 64s instead of existing 32s as
it was shown to affect performance
Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This was manifesting as a crash when FAT Dump extraction was attempted on a PPC machine.
Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This was showing up as junk value on PPC /Big endian machines since
it was marked as a byte.
Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Add 60s delay before timeout on polling Bit 31 so that FAT dump can
complete when reset occurs.
Signed-off-by: Somnath Kotur <somnath.kotur@emulex.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Amir Vadai wrote:
> When a stream is paused, and its rule is expired while it is paused,
> no new rule will be configured to the HW when traffic resume.
[...]
> - When stream was resumed, traffic was steered again by RSS, and
> because current-cpu was equal to desired-cpu, ndo_rx_flow_steer
> wasn't called and no rule was configured to the HW.
Fix this by setting the flow's current CPU only in the table for the
newly selected RX queue.
Reported-and-tested-by: Amir Vadai <amirv@dev.mellanox.co.il>
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Removes some bitrot from the au1100fb driver and fix it up so it works again.
Signed-off-by: Manuel Lauss <manuel.lauss@googlemail.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
When blanking an already blanked framebuffer, a kernel NULL pointer
dereference occurred, because mx3fb driver handles all kinds of screen
blanking (normal, vsync suspend, powerdown) in the same way.
Certain programs (Xorg X11 server) first do a normal blank, followed by
a powerdown blank, which triggered the bug.
Add an additional safeguard and make sdc_disable_channel() safe against
multiple calls independent of other logic.
Signed-off-by: Michael Thalmeier <michael.thalmeier@hale.at>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Since commit [e58aa3d2: genirq: Run irq handlers with interrupts disabled],
We run all interrupt handlers with interrupts disabled
and we even check and yell when an interrupt handler
returns with interrupts enabled (see commit [b738a50a:
genirq: Warn when handler enables interrupts]).
So now this flag is a NOOP and can be removed.
Signed-off-by: Yong Zhang <yong.zhang0@gmail.com>
Acked-by: David Brown <davidb@codeaurora.org>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
Having "edid" as char caused a problem in ufx_read_edid() where we
compared "edid[i] != 0xFF". Because of the type difference, the
condition was never true and the error checking failed.
Also I added a __user notation to silence a sparse complaint.
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Florian Tobias Schandinat <FlorianSchandinat@gmx.de>
The Sigmatel/IDT parser should have the same naming convention
for input jacks as the other codecs have.
BugLink: http://bugs.launchpad.net/bugs/859704
Signed-off-by: David Henningsson <david.henningsson@canonical.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
The struct ore_striping_info will be used later in other
structures. And ore_calc_stripe_info as well. Rename them
make struct ore_striping_info public. ore_calc_stripe_info
is still static, will be made public on first use.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
The struct pnfs_osd_data_map data_map member of exofs_sb_info was
never used after mount. In fact all it's members were duplicated
by the ore_layout structure. So just remove the duplicated information.
Also removed some stupid, but perfectly supported, restrictions on
layout parameters. The case where num_devices is not divisible by
mirror_count+1 is perfectly fine since the rotating device view
will eventually use all the devices it can get.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Signed-off-by: Benny Halevy <bhalevy@tonian.com>
ore_components already has a comps member so this leads
to things like comps->comps which is annoying. the name oc
was already used in new code. So rename all old usage of
ore_components comps => ore_components oc.
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
This quiets the following sparse noise:
warning: symbol 'exofs_sync_fs' was not declared. Should it be static?
warning: symbol 'exofs_free_sbi' was not declared. Should it be static?
warning: symbol 'exofs_get_parent' was not declared. Should it be static?
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
This quiets the sparse noise:
warning: symbol '_calc_trunk_info' was not declared. Should it be static?
Signed-off-by: H Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: Boaz Harrosh <bharrosh@panasas.com>
Any driver that selects SND_SOC_WM8994 should also make sure that
MFD_WM8994 is set, since the codec relies on the mfd code:
sound/built-in.o: In function `wm8994_read':
last.c:(.text+0x20160): undefined reference to `wm8994_reg_read'
sound/built-in.o: In function `wm8994_write':
last.c:(.text+0x20e68): undefined reference to `wm8994_reg_write'
This solves the problem by selecting the MFD driver directly
and adding extra 'depends on' statements to make sure that we
respect the dependencies of that driver.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Add zorder support on OMAP4, this feature allows deciding the visibility order
of the overlays based on the zorder value provided as an overlay info parameter
or a sysfs attribute of the overlay object.
Use the overlay cap OMAP_DSS_OVL_CAP_ZORDER to determine whether zorder is
supported for the overlay or not. Use dss feature FEAT_ALPHA_FREE_ZORDER
if the caps are not available.
Ensure that all overlays that are enabled and connected to the same manager
have different zorders. Swapping zorders of 2 enabled overlays currently
requires disabling one of the overlays.
Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Add support for VIDEO3 pipeline on OMAP4:
- Add VIDEO3 pipeline information in dss_features and omapdss.h
- Add VIDEO3 pipeline register coefficients in dispc.h
- Create a new overlay structure corresponding to VIDEO3.
- Make changes in dispc.c for VIDEO3
Signed-off-by: Archit Taneja <archit@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
On OMAP3, in order to enable alpha blending for LCD and TV managers, we needed
to set LCDALPHABLENDERENABLE/TVALPHABLENDERENABLE bits in DISPC_CONFIG. On
OMAP4, alpha blending is always enabled by default, if the above bits are set,
we switch to an OMAP3 compatibility mode where the zorder values in the pipeline
attribute registers are ignored and a fixed priority is configured.
Rename the manager_info member "alpha_enabled" to "partial_alpha_enabled" for
more clarity. Introduce two dss_features FEAT_ALPHA_FIXED_ZORDER and
FEAT_ALPHA_FREE_ZORDER which represent OMAP3-alpha compatibility mode and OMAP4
alpha mode respectively. Introduce an overlay cap for ZORDER. The DSS2 user is
expected to check for the ZORDER cap, if an overlay doesn't have this cap, the
user is expected to set the parameter partial_alpha_enabled. If the overlay has
ZORDER cap, the DSS2 user can assume that alpha blending is already enabled.
Don't support OMAP3 compatibility mode for now. Trying to read/write to
alpha_blending_enabled sysfs attribute issues a warning for OMAP4 and does not
set the LCDALPHABLENDERENABLE/TVALPHABLENDERENABLE bits.
Change alpha_enabled to partial_alpha_enabled in the omap_vout driver. Use
overlay cap "OMAP_DSS_OVL_CAP_GLOBAL_ALPHA" to check if overlay supports alpha
blending or not. Replace this with checks for VIDEO1 pipeline.
Cc: linux-media@vger.kernel.org
Cc: Lajos Molnar <molnar@ti.com>
Signed-off-by: Archit Taneja <archit@ti.com>
Acked-by: Vaibhav Hiremath <hvaibhav@ti.com>
Signed-off-by: Tomi Valkeinen <tomi.valkeinen@ti.com>
Applications may want to read ELD information to
understand what codecs are supported on the HDMI
receiver and handle the a-v delay for better lip-sync.
ELD information is exposed in a device-specific
IFACE_PCM kcontrol. Tested both with amixer and
PulseAudio; with a corresponding patch passthrough modes
are enabled automagically.
ELD control size is set to zero in case of errors or
wrong configurations. No notifications are implemented
for now, it is expected that jack detection is used to
reconfigure the audio outputs.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
As request_percpu_irq() doesn't allow for a percpu interrupt to have
its type configured (it is generally impossible to configure it on all
CPUs at once), add a 'type' argument to enable_percpu_irq().
This allows some low-level, board specific init code to be switched to
a generic API.
[ tglx: Added WARN_ON argument ]
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: Abhijeet Dharmapurikar <adharmap@codeaurora.org>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The ARM GIC interrupt controller offers per CPU interrupts (PPIs),
which are usually used to connect local timers to each core. Each CPU
has its own private interface to the GIC, and only sees the PPIs that
are directly connect to it.
While these timers are separate devices and have a separate interrupt
line to a core, they all use the same IRQ number.
For these devices, request_irq() is not the right API as it assumes
that an IRQ number is visible by a number of CPUs (through the
affinity setting), but makes it very awkward to express that an IRQ
number can be handled by all CPUs, and yet be a different interrupt
line on each CPU, requiring a different dev_id cookie to be passed
back to the handler.
The *_percpu_irq() functions is designed to overcome these
limitations, by providing a per-cpu dev_id vector:
int request_percpu_irq(unsigned int irq, irq_handler_t handler,
const char *devname, void __percpu *percpu_dev_id);
void free_percpu_irq(unsigned int, void __percpu *);
int setup_percpu_irq(unsigned int irq, struct irqaction *new);
void remove_percpu_irq(unsigned int irq, struct irqaction *act);
void enable_percpu_irq(unsigned int irq);
void disable_percpu_irq(unsigned int irq);
The API has a number of limitations:
- no interrupt sharing
- no threading
- common handler across all the CPUs
Once the interrupt is requested using setup_percpu_irq() or
request_percpu_irq(), it must be enabled by each core that wishes its
local interrupt to be delivered.
Based on an initial patch by Thomas Gleixner.
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Link: http://lkml.kernel.org/r/1316793788-14500-2-git-send-email-marc.zyngier@arm.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
After checking the code and datasheet, I think what we want in the second
snd_soc_update_bits call is to update WM8741_DACRMSB_ATTENUATION register
instead of WM8741_DACRLSB_ATTENUATION.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
We have __exit annotation for txx9aclc_generic_remove(),
thus add __devexit_p to wrap it.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Acked-by: Mika Westerberg <mika.westerberg@iki.fi>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
It is exported via resume callback of struct dev_pm_ops rather than referenced
directly and so should be staticised.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
This assignment is done by the snd_soc_register_codec so there is no need
to redo it in probe function of a codec driver.
Signed-off-by: Axel Lin <axel.lin@gmail.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
One thing puzzled me is that in JBOD case, the per-disk writeout
performance is smaller than the corresponding single-disk case even
when they have comparable bdi_thresh. Tracing shows find that in single
disk case, bdi_writeback is always kept high while in JBOD case, it
could drop low from time to time and correspondingly bdi_reclaimable
could sometimes rush high.
The fix is to watch bdi_reclaimable and kick background writeback as
soon as it goes high. This resembles the global background threshold
but in per-bdi manner. The trick is, as long as bdi_reclaimable does
not go high, bdi_writeback naturally won't go low because
bdi_reclaimable+bdi_writeback ~= bdi_thresh.
With less fluctuated writeback pages, JBOD performance is observed to
increase noticeably in various cases.
vmstat:nr_written values before/after patch:
3.1.0-rc4-wo-underrun+ 3.1.0-rc4-bgthresh3+
------------------------ ------------------------
125596480 +25.9% 158179363 JBOD-10HDD-16G/ext4-100dd-1M-24p-16384M-20:10-X
61790815 +110.4% 130032231 JBOD-10HDD-16G/ext4-10dd-1M-24p-16384M-20:10-X
58853546 -0.1% 58823828 JBOD-10HDD-16G/ext4-1dd-1M-24p-16384M-20:10-X
110159811 +24.7% 137355377 JBOD-10HDD-16G/xfs-100dd-1M-24p-16384M-20:10-X
69544762 +10.8% 77080047 JBOD-10HDD-16G/xfs-10dd-1M-24p-16384M-20:10-X
50644862 +0.5% 50890006 JBOD-10HDD-16G/xfs-1dd-1M-24p-16384M-20:10-X
42677090 +28.0% 54643527 JBOD-10HDD-thresh=100M/ext4-100dd-1M-24p-16384M-100M:10-X
47491324 +13.3% 53785605 JBOD-10HDD-thresh=100M/ext4-10dd-1M-24p-16384M-100M:10-X
52548986 +0.9% 53001031 JBOD-10HDD-thresh=100M/ext4-1dd-1M-24p-16384M-100M:10-X
26783091 +36.8% 36650248 JBOD-10HDD-thresh=100M/xfs-100dd-1M-24p-16384M-100M:10-X
35526347 +14.0% 40492312 JBOD-10HDD-thresh=100M/xfs-10dd-1M-24p-16384M-100M:10-X
44670723 -1.1% 44177606 JBOD-10HDD-thresh=100M/xfs-1dd-1M-24p-16384M-100M:10-X
127996037 +22.4% 156719990 JBOD-10HDD-thresh=2G/ext4-100dd-1M-24p-16384M-2048M:10-X
57518856 +3.8% 59677625 JBOD-10HDD-thresh=2G/ext4-10dd-1M-24p-16384M-2048M:10-X
51919909 +12.2% 58269894 JBOD-10HDD-thresh=2G/ext4-1dd-1M-24p-16384M-2048M:10-X
86410514 +79.0% 154660433 JBOD-10HDD-thresh=2G/xfs-100dd-1M-24p-16384M-2048M:10-X
40132519 +38.6% 55617893 JBOD-10HDD-thresh=2G/xfs-10dd-1M-24p-16384M-2048M:10-X
48423248 +7.5% 52042927 JBOD-10HDD-thresh=2G/xfs-1dd-1M-24p-16384M-2048M:10-X
206041046 +44.1% 296846536 JBOD-10HDD-thresh=4G/xfs-100dd-1M-24p-16384M-4096M:10-X
72312903 -19.4% 58272885 JBOD-10HDD-thresh=4G/xfs-10dd-1M-24p-16384M-4096M:10-X
50635672 -0.5% 50384787 JBOD-10HDD-thresh=4G/xfs-1dd-1M-24p-16384M-4096M:10-X
68308534 +115.7% 147324758 JBOD-10HDD-thresh=800M/ext4-100dd-1M-24p-16384M-800M:10-X
57882933 +14.5% 66269621 JBOD-10HDD-thresh=800M/ext4-10dd-1M-24p-16384M-800M:10-X
52183472 +12.8% 58855181 JBOD-10HDD-thresh=800M/ext4-1dd-1M-24p-16384M-800M:10-X
53788956 +94.2% 104460352 JBOD-10HDD-thresh=800M/xfs-100dd-1M-24p-16384M-800M:10-X
44493342 +35.5% 60298210 JBOD-10HDD-thresh=800M/xfs-10dd-1M-24p-16384M-800M:10-X
42641209 +18.9% 50681038 JBOD-10HDD-thresh=800M/xfs-1dd-1M-24p-16384M-800M:10-X
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
Keep a minimal pool of dirty pages for each bdi, so that the disk IO
queues won't underrun. Also gently increase a small bdi_thresh to avoid
it stuck in 0 for some light dirtied bdi.
It's particularly useful for JBOD and small memory system.
It may result in (pos_ratio > 1) at the setpoint and push the dirty
pages high. This is more or less intended because the bdi is in the
danger of IO queue underflow.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
The dirty pause time shall ultimately be controlled by adjusting
nr_dirtied_pause, since there is relationship
pause = pages_dirtied / task_ratelimit
Assuming
pages_dirtied ~= nr_dirtied_pause
task_ratelimit ~= dirty_ratelimit
We get
nr_dirtied_pause ~= dirty_ratelimit * desired_pause
Here dirty_ratelimit is preferred over task_ratelimit because it's
more stable.
It's also important to limit possible large transitional errors:
- bw is changing quickly
- pages_dirtied << nr_dirtied_pause on entering dirty exceeded area
- pages_dirtied >> nr_dirtied_pause on btrfs (to be improved by a
separate fix, but still expect non-trivial errors)
So we end up using the above formula inside clamp_val().
The best test case for this code is to run 100 "dd bs=4M" tasks on
btrfs and check its pause time distribution.
Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>