29 Aug, 2012
17 commits
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Initialize config.of_node for regulator before registering.
This is needed for DT based regulator support.Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Signed-off-by: Axel Lin
Acked-by: Linus Walleij
Signed-off-by: Mark Brown -
To set REGULATOR_MODE_IDLE mode, what we do is to clear DC1_ACTIVE and
DC1_SLEEP bits, this can be done in one wm8400_set_bits() call.Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
wm831x_reg_read() returns negative error code on failure.
This prevents using the error code as the value read.Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Below is the buck_pmap mapping table:
BUCK1: mask = 1 << 0, shift = 0
BUCK2: mask = 1 << 1, shift = 1
BUCK3: mask = 1 << 2, shift = 2
BUCK4: mask = 1 << 3, shift = 3The mask and shift can be easily calculated by:
mask = 1 << BUCK_ID
shift = BUCK_IDThis patch defines BUCK_FPWM_MASK and BUCK_FPWM_SHIFT macros to replace
buck_pmap mapping table.Signed-off-by: Axel Lin
Acked-by: Milo(Woogyom) Kim
Tested-by: Milo(Woogyom) Kim
Signed-off-by: Mark Brown -
We already know the mask in lp8788_init_dvs() function, and we can update
the corresponding bit for default_dvs_mode in lp8788_init_dvs() function.
This function looks not necessary to me.Signed-off-by: Axel Lin
Acked-by: Milo(Woogyom) Kim
Tested-by: Milo(Woogyom) Kim
Signed-off-by: Mark Brown -
For fixed voltage, the n_voltages should be 1 rather than 0.
Signed-off-by: Axel Lin
Acked-by: Milo(Woogyom) Kim
Signed-off-by: Mark Brown -
Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Use mc13xxx_reg_rmw rather than a mc13xxx_reg_read and a mc13xxx_reg_write calls.
This logic to set MC13892_SWITCHERS0_SWxHI bit is pretty simple:
if (volt > 1375000)
set MC13892_SWITCHERS0_SWxHI bit
else if (volt < 1100000)
clear MC13892_SWITCHERS0_SWxHI bit
else
leave MC13892_SWITCHERS0_SWxHI bit untouchedWe already know the selector, so we don't need to calculate the selector again.
Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Then we can remove lock/unlock around the caller.
Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Then we can remove lock/unlock around the caller.
Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
The voltage selection logic is supposed to find the samllest voltage falls
within specified range. When using equation to calculate vsel, we need to
ensure the requested min_uV meet the range of using the equation.
Otherwise we may select a voltage that is out of specified range.For example, in the case vsel = 62 means select voltage of 2100000uV.
What we want is to ensure the requested min_uV = 2100000. And this also means in the case min_uV > 2100000, vsel = 62
does not meet the request.Also calling twl6030smps_list_voltage() for all cases to ensure the selected
voltage still in bounds.Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
This was missing until now and the underlying
_regulator_do_set_voltage is using this value when calling list_voltage.Signed-off-by: Axel Lin
Signed-off-by: Mark Brown -
The number of regulator is known at compile time, use array to save pointer to
rdev makes the code simpler.Signed-off-by: Axel Lin
Signed-off-by: Mark Brown
23 Aug, 2012
8 commits
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Pull drm fixes from Dave Airlie:
"Intel: edid fixes, power consumption fix, s/r fix, haswell fixRadeon: BIOS loading fixes for UEFI and Thunderbolt machines, better
MSAA validation, lockup timeout fixes, modesetting fixesOne udl dpms fix, one vmwgfx fix, a couple of trivial core changes.
There is an export added to ACPI as part of the radeon bios fixes.
I've also included the fbcon flashing cursor vs deinit race fix, that
seems the simplest place to start"Trivial conflict in drivers/video/console/fbcon.c due to me having
already applied the fbcon flashing cursor vs deinit race fix, and Dave
had added a comment in there too.* 'drm-fixes' of git://people.freedesktop.org/~airlied/linux: (22 commits)
fbcon: fix race condition between console lock and cursor timer (v1.1)
drm: Add missing static storage class specifiers in drm_proc.c file
drm/udl: dpms off the crtc when disabled.
drm: Remove two unused fields from struct drm_display_mode
drm: stop vmgfx driver explosion
drm/radeon/ss: use num_crtc rather than hardcoded 6
Revert "drm/radeon: fix bo creation retry path"
drm/i915: use hsw rps tuning values everywhere on gen6+
drm/radeon: split ATRM support out from the ATPX handler (v3)
drm/radeon: convert radeon vfct code to use acpi_get_table_with_size
ACPI: export symbol acpi_get_table_with_size
drm/radeon: implement ACPI VFCT vbios fetch (v3)
drm/radeon/kms: extend the Fujitsu D3003-S2 board connector quirk to cover later silicon stepping
drm/radeon: fix checking of MSAA renderbuffers on r600-r700
drm/radeon: allow CMASK and FMASK in the CS checker on r600-r700
drm/radeon: init lockup timeout on ring init
drm/radeon: avoid turning off spread spectrum for used pll
drm/i915: fall back to bit-banging if GMBUS fails in CRT EDID reads
drm/i915: extract connector update from intel_ddc_get_modes() for reuse
drm/i915: fix hsw uncached pte
... -
Pull SCSI target fixes from Nicholas Bellinger:
"The executive summary includes:- Post-merge review comments for tcm_vhost (MST + nab)
- Avoid debugging overhead when not debugging for tcm-fc(FCoE) (MDR)
- Fix NULL pointer dereference bug on alloc_page failulre (Yi Zou)
- Fix REPORT_LUNs regression bug with pSCSI export (AlexE + nab)
- Fix regression bug with handling of zero-length data CDBs (nab)
- Fix vhost_scsi_target structure alignment (MST)Thanks again to everyone who contributed a bugfix patch, gave review
feedback on tcm_vhost code, and/or reported a bug during their own
testing over the last weeks.There is one other outstanding bug reported by Roland recently related
to SCSI transfer length overflow handling, for which the current
proposed bugfix has been left in queue pending further testing with
other non iscsi-target based fabric drivers.As the patch is verified with loopback (local SGL memory from SCSI
LLD) + tcm_qla2xxx (TCM allocated SGL memory mapped to PCI HW) fabric
ports, it will be included into the next 3.6-rc-fixes PULL request."* git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending:
target: Remove unused se_cmd.cmd_spdtl
tcm_fc: rcu_deref outside rcu lock/unlock section
tcm_vhost: Fix vhost_scsi_target structure alignment
target: Fix regression bug with handling of zero-length data CDBs
target/pscsi: Fix bug with REPORT_LUNs handling for SCSI passthrough
tcm_vhost: Change vhost_scsi_target->vhost_wwpn to char *
target: fix NULL pointer dereference bug alloc_page() fails to get memory
tcm_fc: Avoid debug overhead when not debugging
tcm_vhost: Post-merge review changes requested by MST
tcm_vhost: Fix incorrect IS_ERR() usage in vhost_scsi_map_iov_to_sgl -
Pull i2c-embedded fixes from Wolfram Sang:
"Some bugfixes for the "embedded" part of the I2C subsystem. The fixes
affect mostly drivers which have been largely reworked lately and
where regressions appeared."* 'i2c-embedded/for-current' of git://git.pengutronix.de/git/wsa/linux:
i2c: tegra: protect suspend/resume callbacks with CONFIG_PM_SLEEP
i2c: diolan-u2c: Fix master_xfer return code
I2C: OMAP: xfer: fix runtime PM get/put balance on error
i2c: nomadik: Add default configuration into the Nomadik I2C driver -
Pull pwm fixes from Thierry Reding:
"These patches fix the Samsung PWM driver and perform some minor
cleanups like fixing checkpatch and sparse warnings.Two redundant error messages are removed and the Kconfig help text for
the PWM subsystem is made more descriptive."* tag 'for-3.6-rc3' of git://gitorious.org/linux-pwm/linux-pwm:
pwm: Improve Kconfig help text
pwm: core: Fix coding style issues
pwm: vt8500: Fix coding style issue
pwm: Remove a redundant error message when devm_request_and_ioremap fails
pwm: samsung: add missing device pointer to struct pwm_chip
pwm: Add missing static storage class specifiers in core.c file -
Pull ceph fixes from Sage Weil:
"Jim's fix closes a narrow race introduced with the msgr changes. One
fix resolves problems with debugfs initialization that Yan found when
multiple client instances are created (e.g., two clusters mounted, or
rbd + cephfs), another one fixes problems with mounting a nonexistent
server subdirectory, and the last one fixes a divide by zero error
from unsanitized ioctl input that Dan Carpenter found."* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
ceph: avoid divide by zero in __validate_layout()
libceph: avoid truncation due to racing banners
ceph: tolerate (and warn on) extraneous dentry from mds
libceph: delay debugfs initialization until we learn global_id -
Pull NFS client bugfixes from Trond Myklebust:
- NFSv3 mounts need to fail if the FSINFO rpc call fails
- Ensure that the NFS commit cache gets torn down when we unload the
NFS module.
- Fix memory scribble issues when interrupting a LAYOUTGET rpc call
- Fix NFSv4 legacy idmapper regressions
- Fix issues with the NFSv4 getacl command
- Fix a regression when using the legacy "mount -t nfs4"* tag 'nfs-for-3.6-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs:
NFSv3: Ensure that do_proc_get_root() reports errors correctly
NFSv4: Ensure that nfs4_alloc_client cleans up on error.
NFS: return -ENOKEY when the upcall fails to map the name
NFS: Clear key construction data if the idmap upcall fails
NFSv4: Don't use private xdr_stream fields in decode_getacl
NFSv4: Fix the acl cache size calculation
NFSv4: Fix pointer arithmetic in decode_getacl
NFS: Alias the nfs module to nfs4
NFS: Fix a regression when loading the NFS v4 module
NFSv4.1: Remove a bogus BUG_ON() in nfs4_layoutreturn_done
pnfs-obj: Better IO pattern in case of unaligned offset
NFS41: add pg_layout_private to nfs_pageio_descriptor
pnfs: nfs4_proc_layoutget returns void
pnfs: defer release of pages in layoutget
nfs: tear down caches in nfs_init_writepagecache when allocation fails -
Pull assorted fixes - mostly vfs - from Al Viro:
"Assorted fixes, with an unexpected detour into vfio refcounting logics
(fell out when digging in an analog of eventpoll race in there)."* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs:
task_work: add a scheduling point in task_work_run()
fs: fix fs/namei.c kernel-doc warnings
eventpoll: use-after-possible-free in epoll_create1()
vfio: grab vfio_device reference *before* exposing the sucker via fd_install()
vfio: get rid of vfio_device_put()/vfio_group_get_device* races
vfio: get rid of open-coding kref_put_mutex
introduce kref_put_mutex()
vfio: don't dereference after kfree...
mqueue: lift mnt_want_write() outside ->i_mutex, clean up a bit
22 Aug, 2012
15 commits
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It seems commit 4a9d4b02 (switch fput to task_work_add) reintroduced
the problem addressed in commit 944be0b2 (close_files(): add scheduling
point)If a server process with a lot of files (say 2 million tcp sockets)
is killed, we can spend a lot of time in task_work_run() and trigger
a soft lockup.Signed-off-by: Eric Dumazet
Signed-off-by: Al Viro -
Fix kernel-doc warnings in fs/namei.c:
Warning(fs/namei.c:360): No description found for parameter 'inode'
Warning(fs/namei.c:672): No description found for parameter 'nd'Signed-off-by: Randy Dunlap
Cc: Alexander Viro
Cc: linux-fsdevel@vger.kernel.org
Signed-off-by: Al Viro -
As soon as we'd installed the file into descriptor table, it can
get closed by another thread. Freeing ep in process...Signed-off-by: Al Viro
-
It's not critical (anymore) since another thread closing the file will block
on ->device_lock before it gets to dropping the final reference, but it's
definitely cleaner that way...Acked-by: Alex Williamson
Signed-off-by: Al Viro -
we really need to make sure that dropping the last reference happens
under the group->device_lock; otherwise a loop (under device_lock)
might find vfio_device instance that is being freed right now, has
already dropped the last reference and waits on device_lock to exclude
the sucker from the list.Acked-by: Alex Williamson
Signed-off-by: Al Viro -
Acked-by: Alex Williamson
Signed-off-by: Al Viro -
equivalent of
mutex_lock(mutex);
if (!kref_put(kref, release))
mutex_unlock(mutex);Signed-off-by: Al Viro
-
Acked-by: Alex Williamson
Signed-off-by: Al Viro -
So we've had a fair few reports of fbcon handover breakage between
efi/vesafb and i915 surface recently, so I dedicated a couple of
days to finding the problem.Essentially the last thing we saw was the conflicting framebuffer
message and that was all.So after much tracing with direct netconsole writes (printks
under console_lock not so useful), I think I found the race.Thread A (driver load) Thread B (timer thread)
unbind_con_driver -> |
bind_con_driver -> |
vc->vc_sw->con_deinit -> |
fbcon_deinit -> |
console_lock() |
| |
| fbcon_flashcursor timer fires
| console_lock()
del_timer_sync
(BOOM)Of course because all of this is under the console lock,
we never see anything, also since we also just unbound the active
console guess what we never see anything.Hopefully this fixes the problem for anyone seeing vesafb->kms
driver handoff.v1.1: add comment suggestion from Alan.
Cc: stable@vger.kernel.org
Signed-off-by: Dave Airlie -
Merge fixes from Andrew Morton.
Random drivers and some VM fixes.
* emailed patches from Andrew Morton : (17 commits)
mm: compaction: Abort async compaction if locks are contended or taking too long
mm: have order > 0 compaction start near a pageblock with free pages
rapidio/tsi721: fix unused variable compiler warning
rapidio/tsi721: fix inbound doorbell interrupt handling
drivers/rtc/rtc-rs5c348.c: fix hour decoding in 12-hour mode
mm: correct page->pfmemalloc to fix deactivate_slab regression
drivers/rtc/rtc-pcf2123.c: initialize dynamic sysfs attributes
mm/compaction.c: fix deferring compaction mistake
drivers/misc/sgi-xp/xpc_uv.c: SGI XPC fails to load when cpu 0 is out of IRQ resources
string: do not export memweight() to userspace
hugetlb: update hugetlbpage.txt
checkpatch: add control statement test to SINGLE_STATEMENT_DO_WHILE_MACRO
mm: hugetlbfs: correctly populate shared pmd
cciss: fix incorrect scsi status reporting
Documentation: update mount option in filesystem/vfat.txt
mm: change nr_ptes BUG_ON to WARN_ON
cs5535-clockevt: typo, it's MFGPT, not MFPGT -
Pull media fixes from Mauro Carvalho Chehab:
"For bug fixes, at soc_camera, si470x, uvcvideo, iguanaworks IR driver,
radio_shark Kbuild fixes, and at the V4L2 core (radio fixes)."* 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-media:
[media] media: soc_camera: don't clear pix->sizeimage in JPEG mode
[media] media: mx2_camera: Fix clock handling for i.MX27
[media] video: mx2_camera: Use clk_prepare_enable/clk_disable_unprepare
[media] video: mx1_camera: Use clk_prepare_enable/clk_disable_unprepare
[media] media: mx3_camera: buf_init() add buffer state check
[media] radio-shark2: Only compile led support when CONFIG_LED_CLASS is set
[media] radio-shark: Only compile led support when CONFIG_LED_CLASS is set
[media] radio-shark*: Call cancel_work_sync from disconnect rather then release
[media] radio-shark*: Remove work-around for dangling pointer in usb intfdata
[media] Add USB dependency for IguanaWorks USB IR Transceiver
[media] Add missing logging for rangelow/high of hwseek
[media] VIDIOC_ENUM_FREQ_BANDS fix
[media] mem2mem_testdev: fix querycap regression
[media] si470x: v4l2-compliance fixes
[media] DocBook: Remove a spurious character
[media] uvcvideo: Reset the bytesused field when recycling an erroneous buffer -
Pull networking update from David Miller:
"A couple weeks of bug fixing in there. The largest chunk is all the
broken crap Amerigo Wang found in the netpoll layer."1) netpoll and it's users has several serious bugs:
a) uses GFP_KERNEL with locks held
b) interfaces requiring interrupts disabled are called with them
enabled
c) and vice versa
d) VLAN tag demuxing, as per all other RX packet input paths, is not
appliedAll from Amerigo Wang.
2) Hopefully cure the ipv4 mapped ipv6 address TCP early demux bugs for
good, from Neal Cardwell.3) Unlike AF_UNIX, AF_PACKET sockets don't set a default credentials
when the user doesn't specify one explicitly during sendmsg().
Instead we attach an empty (zero) SCM credential block which is
definitely not what we want. Fix from Eric Dumazet.4) IPv6 illegally invokes netdevice notifiers with RCU lock held, fix
from Ben Hutchings.5) inet_csk_route_child_sock() checks wrong inet options pointer, fix
from Christoph Paasch.6) When AF_PACKET is used for transmit, packet loopback doesn't behave
properly when a socket fanout is enabled, from Eric Leblond.7) On bluetooth l2cap channel create failure, we leak the socket, from
Jaganath Kanakkassery.8) Fix all the netprio file handling bugs found by Al Viro, from John
Fastabend.9) Several error return and NULL deref bug fixes in networking drivers
from Julia Lawall.10) A large smattering of struct padding et al. kernel memory leaks to
userspace found of Mathias Krause.11) Conntrack expections in netfilter can access an uninitialized timer,
fix from Pablo Neira Ayuso.12) Several netfilter SIP tracker bug fixes from Patrick McHardy.
13) IPSEC ipv6 routes are not initialized correctly all the time,
resulting in an OOPS in inet_putpeer(). Also from Patrick McHardy.14) Bridging does rcu_dereference() outside of RCU protected area, from
Stephen Hemminger.15) Fix routing cache removal performance regression when looking up
output routes that have a local destination. From Zheng Yan.* git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (87 commits)
af_netlink: force credentials passing [CVE-2012-3520]
ipv4: fix ip header ident selection in __ip_make_skb()
ipv4: Use newinet->inet_opt in inet_csk_route_child_sock()
tcp: fix possible socket refcount problem
net: tcp: move sk_rx_dst_set call after tcp_create_openreq_child()
net/core/dev.c: fix kernel-doc warning
netconsole: remove a redundant netconsole_target_put()
net: ipv6: fix oops in inet_putpeer()
net/stmmac: fix issue of clk_get for Loongson1B.
caif: Do not dereference NULL in chnl_recv_cb()
af_packet: don't emit packet on orig fanout group
drivers/net/irda: fix error return code
drivers/net/wan/dscc4.c: fix error return code
drivers/net/wimax/i2400m/fw.c: fix error return code
smsc75xx: add missing entry to MAINTAINERS
net: qmi_wwan: new devices: UML290 and K5006-Z
net: sh_eth: Add eth support for R8A7779 device
netdev/phy: skip disabled mdio-mux nodes
dt: introduce for_each_available_child_of_node, of_get_next_available_child
net: netprio: fix cgrp create and write priomap race
... -
Jim Schutt reported a problem that pointed at compaction contending
heavily on locks. The workload is straight-forward and in his own words;The systems in question have 24 SAS drives spread across 3 HBAs,
running 24 Ceph OSD instances, one per drive. FWIW these servers
are dual-socket Intel 5675 Xeons w/48 GB memory. I've got ~160
Ceph Linux clients doing dd simultaneously to a Ceph file system
backed by 12 of these servers.Early in the test everything looks fine
procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
r b swpd free buff cache si so bi bo in cs us sy id wa st
31 15 0 287216 576 38606628 0 0 2 1158 2 14 1 3 95 0 0
27 15 0 225288 576 38583384 0 0 18 2222016 203357 134876 11 56 17 15 0
28 17 0 219256 576 38544736 0 0 11 2305932 203141 146296 11 49 23 17 0
6 18 0 215596 576 38552872 0 0 7 2363207 215264 166502 12 45 22 20 0
22 18 0 226984 576 38596404 0 0 3 2445741 223114 179527 12 43 23 22 0and then it goes to pot
procs -------------------memory------------------ ---swap-- -----io---- --system-- -----cpu-------
r b swpd free buff cache si so bi bo in cs us sy id wa st
163 8 0 464308 576 36791368 0 0 11 22210 866 536 3 13 79 4 0
207 14 0 917752 576 36181928 0 0 712 1345376 134598 47367 7 90 1 2 0
123 12 0 685516 576 36296148 0 0 429 1386615 158494 60077 8 84 5 3 0
123 12 0 598572 576 36333728 0 0 1107 1233281 147542 62351 7 84 5 4 0
622 7 0 660768 576 36118264 0 0 557 1345548 151394 59353 7 85 4 3 0
223 11 0 283960 576 36463868 0 0 46 1107160 121846 33006 6 93 1 1 0Note that system CPU usage is very high blocks being written out has
dropped by 42%. He analysed this with perf and foundperf record -g -a sleep 10
perf report --sort symbol --call-graph fractal,5
34.63% [k] _raw_spin_lock_irqsave
|
|--97.30%-- isolate_freepages
| compaction_alloc
| unmap_and_move
| migrate_pages
| compact_zone
| compact_zone_order
| try_to_compact_pages
| __alloc_pages_direct_compact
| __alloc_pages_slowpath
| __alloc_pages_nodemask
| alloc_pages_vma
| do_huge_pmd_anonymous_page
| handle_mm_fault
| do_page_fault
| page_fault
| |
| |--87.39%-- skb_copy_datagram_iovec
| | tcp_recvmsg
| | inet_recvmsg
| | sock_recvmsg
| | sys_recvfrom
| | system_call
| | __recv
| | |
| | --100.00%-- (nil)
| |
| --12.61%-- memcpy
--2.70%-- [...]There was other data but primarily it is all showing that compaction is
contended heavily on the zone->lock and zone->lru_lock.commit [b2eef8c0: mm: compaction: minimise the time IRQs are disabled
while isolating pages for migration] noted that it was possible for
migration to hold the lru_lock for an excessive amount of time. Very
broadly speaking this patch expands the concept.This patch introduces compact_checklock_irqsave() to check if a lock
is contended or the process needs to be scheduled. If either condition
is true then async compaction is aborted and the caller is informed.
The page allocator will fail a THP allocation if compaction failed due
to contention. This patch also introduces compact_trylock_irqsave()
which will acquire the lock only if it is not contended and the process
does not need to schedule.Reported-by: Jim Schutt
Tested-by: Jim Schutt
Signed-off-by: Mel Gorman
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Commit 7db8889ab05b ("mm: have order > 0 compaction start off where it
left") introduced a caching mechanism to reduce the amount work the free
page scanner does in compaction. However, it has a problem. Consider
two process simultaneously scanning free pagesC
Process A M S F
|---------------------------------------|
Process B M FSC is zone->compact_cached_free_pfn
S is cc->start_pfree_pfn
M is cc->migrate_pfn
F is cc->free_pfnIn this diagram, Process A has just reached its migrate scanner, wrapped
around and updated compact_cached_free_pfn accordingly.Simultaneously, Process B finishes isolating in a block and updates
compact_cached_free_pfn again to the location of its free scanner.Process A moves to "end_of_zone - one_pageblock" and runs this check
if (cc->order > 0 && (!cc->wrapped ||
zone->compact_cached_free_pfn >
cc->start_free_pfn))
pfn = min(pfn, zone->compact_cached_free_pfn);compact_cached_free_pfn is above where it started so the free scanner
skips almost the entire space it should have scanned. When there are
multiple processes compacting it can end in a situation where the entire
zone is not being scanned at all. Further, it is possible for two
processes to ping-pong update to compact_cached_free_pfn which is just
random.Overall, the end result wrecks allocation success rates.
There is not an obvious way around this problem without introducing new
locking and state so this patch takes a different approach.First, it gets rid of the skip logic because it's not clear that it
matters if two free scanners happen to be in the same block but with
racing updates it's too easy for it to skip over blocks it should not.Second, it updates compact_cached_free_pfn in a more limited set of
circumstances.If a scanner has wrapped, it updates compact_cached_free_pfn to the end
of the zone. When a wrapped scanner isolates a page, it updates
compact_cached_free_pfn to point to the highest pageblock it
can isolate pages from.If a scanner has not wrapped when it has finished isolated pages it
checks if compact_cached_free_pfn is pointing to the end of the
zone. If so, the value is updated to point to the highest
pageblock that pages were isolated from. This value will not
be updated again until a free page scanner wraps and resets
compact_cached_free_pfn.This is not optimal and it can still race but the compact_cached_free_pfn
will be pointing to or very near a pageblock with free pages.Signed-off-by: Mel Gorman
Reviewed-by: Rik van Riel
Reviewed-by: Minchan Kim
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds -
Fix unused variable compiler warning when built with CONFIG_RAPIDIO_DEBUG
option off.This patch is applicable to kernel versions starting from v3.2
Signed-off-by: Alexandre Bounine
Cc: Matt Porter
Cc:
Signed-off-by: Andrew Morton
Signed-off-by: Linus Torvalds
