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* Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2011-06-191-0/+1
|\ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rcu: Move RCU_BOOST #ifdefs to header file rcu: use softirq instead of kthreads except when RCU_BOOST=y rcu: Use softirq to address performance regression rcu: Simplify curing of load woes
| * rcu: Use softirq to address performance regressionShaohua Li2011-06-141-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit a26ac2455ffcf3(rcu: move TREE_RCU from softirq to kthread) introduced performance regression. In an AIM7 test, this commit degraded performance by about 40%. The commit runs rcu callbacks in a kthread instead of softirq. We observed high rate of context switch which is caused by this. Out test system has 64 CPUs and HZ is 1000, so we saw more than 64k context switch per second which is caused by RCU's per-CPU kthread. A trace showed that most of the time the RCU per-CPU kthread doesn't actually handle any callbacks, but instead just does a very small amount of work handling grace periods. This means that RCU's per-CPU kthreads are making the scheduler do quite a bit of work in order to allow a very small amount of RCU-related processing to be done. Alex Shi's analysis determined that this slowdown is due to lock contention within the scheduler. Unfortunately, as Peter Zijlstra points out, the scheduler's real-time semantics require global action, which means that this contention is inherent in real-time scheduling. (Yes, perhaps someone will come up with a workaround -- otherwise, -rt is not going to do well on large SMP systems -- but this patch will work around this issue in the meantime. And "the meantime" might well be forever.) This patch therefore re-introduces softirq processing to RCU, but only for core RCU work. RCU callbacks are still executed in kthread context, so that only a small amount of RCU work runs in softirq context in the common case. This should minimize ksoftirqd execution, allowing us to skip boosting of ksoftirqd for CONFIG_RCU_BOOST=y kernels. Signed-off-by: Shaohua Li <shaohua.li@intel.com> Tested-by: "Alex,Shi" <alex.shi@intel.com> Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
* | Documentation: fix cgroup typos and formattingJörg Sommer2011-06-153-13/+13
| | | | | | | | | | | | | | | | | | Fix format and spelling. Signed-off-by: Jörg Sommer <joerg@alea.gnuu.de> Acked-by: Paul Menage <menage@google.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Documentation: update cgroupfs mount pointJörg Sommer2011-06-1511-94/+109
| | | | | | | | | | | | | | | | | | | | | | According to commit 676db4af0430 ("cgroupfs: create /sys/fs/cgroup to mount cgroupfs on") the canonical mountpoint for the cgroup filesystem is /sys/fs/cgroup. Hence, this should be used in the documentation. Signed-off-by: Jörg Sommer <joerg@alea.gnuu.de> Acked-by: Paul Menage <menage@google.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Documentation: update kmemleak supported archsMaxin B. John2011-06-151-1/+3
| | | | | | | | | | | | | | | | | | | | | | | | Instead of listing the architectures that are supported by kmemleak in Documentation/kmemleak.txt, just refer people to the list of supported architecutures in lib/Kconfig.debug so that Documentation/kmemleak.txt does not need more updates for this. Signed-off-by: Maxin B. John <maxin.john@gmail.com> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Documentation: update printk-formats.txtAndrew Murray2011-06-151-2/+117
| | | | | | | | | | | | | | | | | | This patch updates the incomplete documentation concerning the printk extended format specifiers. Signed-off-by: Andrew Murray <amurray@mpc-data.co.uk> Signed-off-by: Randy Dunlap <randy.dunlap@oracle.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Documentation/feature-removal-schedule.txt: remove ns_cgroup from ↵akpm@linux-foundation.org2011-06-151-17/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | feature-removal-schedule.txt Commit a77aea92010acf ("cgroup: remove the ns_cgroup") removed the ns_cgroup but it forgot to remove the related doc in feature-removal-schedule.txt. Signed-off-by: WANG Cong <xiyou.wangcong@gmail.com> Cc: Daniel Lezcano <daniel.lezcano@free.fr> Cc: Serge E. Hallyn <serge.hallyn@canonical.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | memcg: add documentation for the memory.numastat APIYing Han2011-06-151-0/+19
| | | | | | | | | | | | | | | | | | | | [akpm@linux-foundation.org: rework text, fit it into 80-cols] Signed-off-by: Ying Han <yinghan@google.com> Reviewed-by: KOSAKI Motohiro <kosaki.motohiro@jp.fujitsu.com> Acked-by: Balbir Singh <bsingharora@gmail.com> Acked-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | backlight: new driver for the ADP8870 backlight devicesMichael Hennerich2011-06-151-0/+56
| | | | | | | | | | | | | | | | Signed-off-by: Michael Hennerich <michael.hennerich@analog.com> Signed-off-by: Mike Frysinger <vapier@gentoo.org> Cc: Richard Purdie <rpurdie@rpsys.net> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* | Merge branch 'for-linus' of git://neil.brown.name/mdLinus Torvalds2011-06-141-1/+1
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus' of git://neil.brown.name/md: md/raid5: remove unusual use of bio_iovec_idx() md/raid5: fix FUA request handling in ops_run_io() md/raid5: fix raid5_set_bi_hw_segments md:Documentation/md.txt - fix typo md/bitmap: remove unused fields from struct bitmap md/bitmap: use proper accessor macro md: check ->hot_remove_disk when removing disk md: Using poll /proc/mdstat can monitor the events of adding a spare disks MD: use is_power_of_2 macro MD: raid5 do not set fullsync MD: support initial bitmap creation in-kernel MD: add sync_super to mddev_t struct MD: raid1 changes to allow use by device mapper MD: move thread wakeups into resume MD: possible typo MD: no sync IO while suspended MD: no integrity register if no gendisk
| * | md:Documentation/md.txt - fix typoNeilBrown2011-06-091-1/+1
| |/ | | | | | | | | Reported-by: CoolCold <coolthecold@gmail.com> Signed-off-by: NeilBrown <neilb@suse.de>
* | usb-storage: redo incorrect readsAlan Stern2011-06-071-0/+2
|/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Some USB mass-storage devices have bugs that cause them not to handle the first READ(10) command they receive correctly. The Corsair Padlock v2 returns completely bogus data for its first read (possibly it returns the data in encrypted form even though the device is supposed to be unlocked). The Feiya SD/SDHC card reader fails to complete the first READ(10) command after it is plugged in or after a new card is inserted, returning a status code that indicates it thinks the command was invalid, which prevents the kernel from retrying the read. Since the first read of a new device or a new medium is for the partition sector, the kernel is unable to retrieve the device's partition table. Users have to manually issue an "hdparm -z" or "blockdev --rereadpt" command before they can access the device. This patch (as1470) works around the problem. It adds a new quirk flag, US_FL_INVALID_READ10, indicating that the first READ(10) should always be retried immediately, as should any failing READ(10) commands (provided the preceding READ(10) command succeeded, to avoid getting stuck in a loop). The patch also adds appropriate unusual_devs entries containing the new flag. Signed-off-by: Alan Stern <stern@rowland.harvard.edu> Tested-by: Sven Geggus <sven-usbst@geggus.net> Tested-by: Paul Hartman <paul.hartman+linux@gmail.com> CC: Matthew Dharm <mdharm-usb@one-eyed-alien.net> CC: <stable@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
* Merge git://git.infradead.org/iommu-2.6Linus Torvalds2011-06-021-1/+4
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.infradead.org/iommu-2.6: intel-iommu: Fix off-by-one in RMRR setup intel-iommu: Add domain check in domain_remove_one_dev_info intel-iommu: Remove Host Bridge devices from identity mapping intel-iommu: Use coherent DMA mask when requested intel-iommu: Dont cache iova above 32bit intel-iommu: Speed up processing of the identity_mapping function intel-iommu: Check for identity mapping candidate using system dma mask intel-iommu: Only unlink device domains from iommu intel-iommu: Enable super page (2MiB, 1GiB, etc.) support intel-iommu: Flush unmaps at domain_exit intel-iommu: Remove obsolete comment from detect_intel_iommu intel-iommu: fix VT-d PMR disable for TXT on S3 resume
| * intel-iommu: Enable super page (2MiB, 1GiB, etc.) supportYouquan Song2011-06-011-1/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There are no externally-visible changes with this. In the loop in the internal __domain_mapping() function, we simply detect if we are mapping: - size >= 2MiB, and - virtual address aligned to 2MiB, and - physical address aligned to 2MiB, and - on hardware that supports superpages. (and likewise for larger superpages). We automatically use a superpage for such mappings. We never have to worry about *breaking* superpages, since we trust that we will always *unmap* the same range that was mapped. So all we need to do is ensure that dma_pte_clear_range() will also cope with superpages. Adjust pfn_to_dma_pte() to take a superpage 'level' as an argument, so it can return a PTE at the appropriate level rather than always extending the page tables all the way down to level 1. Again, this is simplified by the fact that we should never encounter existing small pages when we're creating a mapping; any old mapping that used the same virtual range will have been entirely removed and its obsolete page tables freed. Provide an 'intel_iommu=sp_off' argument on the command line as a chicken bit. Not that it should ever be required. == The original commit seen in the iommu-2.6.git was Youquan's implementation (and completion) of my own half-baked code which I'd typed into an email. Followed by half a dozen subsequent 'fixes'. I've taken the unusual step of rewriting history and collapsing the original commits in order to keep the main history simpler, and make life easier for the people who are going to have to backport this to older kernels. And also so I can give it a more coherent commit comment which (hopefully) gives a better explanation of what's going on. The original sequence of commits leading to identical code was: Youquan Song (3): intel-iommu: super page support intel-iommu: Fix superpage alignment calculation error intel-iommu: Fix superpage level calculation error in dma_pfn_level_pte() David Woodhouse (4): intel-iommu: Precalculate superpage support for dmar_domain intel-iommu: Fix hardware_largepage_caps() intel-iommu: Fix inappropriate use of superpages in __domain_mapping() intel-iommu: Fix phys_pfn in __domain_mapping for sglist pages Signed-off-by: Youquan Song <youquan.song@intel.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* | lguest: remove support for VIRTIO_F_NOTIFY_ON_EMPTY.Rusty Russell2011-05-301-19/+1
| | | | | | | | | | | | No virtio device does this any more, so no need to clutter lguest with it. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | lguest: fix up compilation after moveRusty Russell2011-05-302-2/+2
| | | | | | | | | | | | | | ed16648eb5b86917f0b90bdcdbc857202da72f90 "Move kvm, uml, and lguest subdirectories" broke the lguest example launcher. Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
* | Merge branch 'for_linus' of ↵Linus Torvalds2011-05-291-184/+0
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86 * 'for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mjg59/platform-drivers-x86: (43 commits) acer-wmi: support integer return type from WMI methods msi-laptop: fix section mismatch in reference from the function load_scm_model_init acer-wmi: support to set communication device state by new wmid method acer-wmi: allow 64-bits return buffer from WMI methods acer-wmi: check the existence of internal 3G device when set capability platform/x86:delete two unused variables support wlan hotkey on Acer Travelmate 5735Z platform-x86: intel_mid_thermal: Fix memory leak platform/x86: Fix Makefile for intel_mid_powerbtn platform/x86: Simplify intel_mid_powerbtn acer-wmi: Delete out-of-date documentation acerhdf: Clean up includes acerhdf: Drop pointless dependency on THERMAL_HWMON acer-wmi: Update MAINTAINERS wmi: Orphan ACPI-WMI driver tc1100-wmi: Orphan driver acer-wmi: does not allow negative number set to initial device state platform/oaktrail: ACPI EC Extra driver for Oaktrail thinkpad_acpi: Convert printks to pr_<level> thinkpad_acpi: Correct !CONFIG_THINKPAD_ACPI_VIDEO warning ...
| * \ Merge branch 'x86-platform-next' into x86-platformMatthew Garrett2011-05-291-184/+0
| |\ \
| | * | acer-wmi: Delete out-of-date documentationCarlos Corbacho2011-05-271-184/+0
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The documentation file for acer-wmi is long out of date, and there's not much point in keeping it around either. Signed-off-by: Carlos Corbacho <carlos@strangeworlds.co.uk> Signed-off-by: Matthew Garrett <mjg@redhat.com>
* | | | Merge branch 'release' of ↵Linus Torvalds2011-05-291-0/+5
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6 * 'release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-acpi-2.6: ACPI EC: remove redundant code ACPI: Add D3 cold state ACPI: processor: fix processor_physically_present in UP kernel ACPI: Split out custom_method functionality into an own driver ACPI: Cleanup custom_method debug stuff ACPI EC: enable MSI workaround for Quanta laptops ACPICA: Update to version 20110413 ACPICA: Execute an orphan _REG method under the EC device ACPICA: Move ACPI_NUM_PREDEFINED_REGIONS to a more appropriate place ACPICA: Update internal address SpaceID for DataTable regions ACPICA: Add more methods eligible for NULL package element removal ACPICA: Split all internal Global Lock functions to new file - evglock ACPI: EC: add another DMI check for ASUS hardware ACPI EC: remove dead code ACPICA: Fix code divergence of global lock handling ACPICA: Use acpi_os_create_lock interface ACPI: osl, add acpi_os_create_lock interface ACPI:Fix goto flows in thermal-sys
| * | | | ACPI: Split out custom_method functionality into an own driverThomas Renninger2011-05-291-0/+5
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With /sys/kernel/debug/acpi/custom_method root can write to arbitrary memory and increase his priveleges, even if these are restricted. -> Make this an own debug .config option and warn about the security issue in the config description. -> Still keep acpi/debugfs.c which now only creates an empty /sys/kernel/debug/acpi directory. There might be other users of it later. Signed-off-by: Thomas Renninger <trenn@suse.de> Acked-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: rui.zhang@intel.com Signed-off-by: Len Brown <len.brown@intel.com>
* | | | Merge branch 'idle-release' of ↵Linus Torvalds2011-05-291-0/+36
|\ \ \ \ | |_|/ / |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6 * 'idle-release' of git://git.kernel.org/pub/scm/linux/kernel/git/lenb/linux-idle-2.6: x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline param x86 idle: deprecate "no-hlt" cmdline param x86 idle APM: deprecate CONFIG_APM_CPU_IDLE x86 idle floppy: deprecate disable_hlt() x86 idle: EXPORT_SYMBOL(default_idle, pm_idle) only when APM demands it x86 idle: clarify AMD erratum 400 workaround idle governor: Avoid lock acquisition to read pm_qos before entering idle cpuidle: menu: fixed wrapping timers at 4.294 seconds
| * | | x86 idle: deprecate mwait_idle() and "idle=mwait" cmdline paramLen Brown2011-05-291-0/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | mwait_idle() is a C1-only idle loop intended to be more efficient than HLT on SMP hardware that supports it. But mwait_idle() has been replaced by the more general mwait_idle_with_hints(), which handles both C1 and deeper C-states. ACPI uses only mwait_idle_with_hints(), and never uses mwait_idle(). Deprecate mwait_idle() and the "idle=mwait" cmdline param to simplify the x86 idle code. After this change, kernels configured with (!CONFIG_ACPI=n && !CONFIG_INTEL_IDLE=n) when run on hardware that support MWAIT will simply use HLT. If MWAIT is desired on those systems, cpuidle and the cpuidle drivers above can be used. cc: x86@kernel.org cc: stable@kernel.org # .39.x Signed-off-by: Len Brown <len.brown@intel.com>
| * | | x86 idle: deprecate "no-hlt" cmdline paramLen Brown2011-05-291-0/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We'd rather that modern machines not check if HLT works on every entry into idle, for the benefit of machines that had marginal electricals 15-years ago. If those machines are still running the upstream kernel, they can use "idle=poll". The only difference will be that they'll now invoke HLT in machine_hlt(). cc: x86@kernel.org # .39.x Signed-off-by: Len Brown <len.brown@intel.com>
| * | | x86 idle APM: deprecate CONFIG_APM_CPU_IDLELen Brown2011-05-291-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | We don't want to export the pm_idle function pointer to modules. Currently CONFIG_APM_CPU_IDLE w/ CONFIG_APM_MODULE forces us to. CONFIG_APM_CPU_IDLE is of dubious value, it runs only on 32-bit uniprocessor laptops that are over 10 years old. It calls into the BIOS during idle, and is known to cause a number of machines to fail. Removing CONFIG_APM_CPU_IDLE and will allow us to stop exporting pm_idle. Any systems that were calling into the APM BIOS at run-time will simply use HLT instead. cc: x86@kernel.org cc: Jiri Kosina <jkosina@suse.cz> cc: stable@kernel.org # .39.x Signed-off-by: Len Brown <len.brown@intel.com>
| * | | x86 idle floppy: deprecate disable_hlt()Len Brown2011-05-291-0/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Plan to remove floppy_disable_hlt in 2012, an ancient workaround with comments that it should be removed. This allows us to remove clutter and a run-time branch from the idle code. WARN_ONCE() on invocation until it is removed. cc: x86@kernel.org cc: stable@kernel.org # .39.x Signed-off-by: Len Brown <len.brown@intel.com>
* | | | Merge branch 'for-linus' of ↵Linus Torvalds2011-05-282-3/+3
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6 * 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs-2.6: (36 commits) Cache xattr security drop check for write v2 fs: block_page_mkwrite should wait for writeback to finish mm: Wait for writeback when grabbing pages to begin a write configfs: remove unnecessary dentry_unhash on rmdir, dir rename fat: remove unnecessary dentry_unhash on rmdir, dir rename hpfs: remove unnecessary dentry_unhash on rmdir, dir rename minix: remove unnecessary dentry_unhash on rmdir, dir rename fuse: remove unnecessary dentry_unhash on rmdir, dir rename coda: remove unnecessary dentry_unhash on rmdir, dir rename afs: remove unnecessary dentry_unhash on rmdir, dir rename affs: remove unnecessary dentry_unhash on rmdir, dir rename 9p: remove unnecessary dentry_unhash on rmdir, dir rename ncpfs: fix rename over directory with dangling references ncpfs: document dentry_unhash usage ecryptfs: remove unnecessary dentry_unhash on rmdir, dir rename hostfs: remove unnecessary dentry_unhash on rmdir, dir rename hfsplus: remove unnecessary dentry_unhash on rmdir, dir rename hfs: remove unnecessary dentry_unhash on rmdir, dir rename omfs: remove unnecessary dentry_unhash on rmdir, dir rneame udf: remove unnecessary dentry_unhash from rmdir, dir rename ...
| * | | | fs: pass exact type of data dirties to ->dirty_inodeChristoph Hellwig2011-05-272-3/+3
| | |_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Tell the filesystem if we just updated timestamp (I_DIRTY_SYNC) or anything else, so that the filesystem can track internally if it needs to push out a transaction for fdatasync or not. This is just the prototype change with no user for it yet. I plan to push large XFS changes for the next merge window, and getting this trivial infrastructure in this window would help a lot to avoid tree interdependencies. Also remove incorrect comments that ->dirty_inode can't block. That has been changed a long time ago, and many implementations rely on it. Signed-off-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
* | | | Merge branch 'core-urgent-for-linus' of ↵Linus Torvalds2011-05-282-14/+39
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip * 'core-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: rcu: Start RCU kthreads in TASK_INTERRUPTIBLE state rcu: Remove waitqueue usage for cpu, node, and boost kthreads rcu: Avoid acquiring rcu_node locks in timer functions atomic: Add atomic_or() Documentation: Add statistics about nested locks rcu: Decrease memory-barrier usage based on semi-formal proof rcu: Make rcu_enter_nohz() pay attention to nesting rcu: Don't do reschedule unless in irq rcu: Remove old memory barriers from rcu_process_callbacks() rcu: Add memory barriers rcu: Fix unpaired rcu_irq_enter() from locking selftests
| * \ \ \ Merge branch 'rcu/urgent' of ↵Ingo Molnar2011-05-281-12/+5
| |\ \ \ \ | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-2.6-rcu into core/urgent
| | * | | | rcu: Decrease memory-barrier usage based on semi-formal proofPaul E. McKenney2011-05-261-12/+5
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | (Note: this was reverted, and is now being re-applied in pieces, with this being the fifth and final piece. See below for the reason that it is now felt to be safe to re-apply this.) Commit d09b62d fixed grace-period synchronization, but left some smp_mb() invocations in rcu_process_callbacks() that are no longer needed, but sheer paranoia prevented them from being removed. This commit removes them and provides a proof of correctness in their absence. It also adds a memory barrier to rcu_report_qs_rsp() immediately before the update to rsp->completed in order to handle the theoretical possibility that the compiler or CPU might move massive quantities of code into a lock-based critical section. This also proves that the sheer paranoia was not entirely unjustified, at least from a theoretical point of view. In addition, the old dyntick-idle synchronization depended on the fact that grace periods were many milliseconds in duration, so that it could be assumed that no dyntick-idle CPU could reorder a memory reference across an entire grace period. Unfortunately for this design, the addition of expedited grace periods breaks this assumption, which has the unfortunate side-effect of requiring atomic operations in the functions that track dyntick-idle state for RCU. (There is some hope that the algorithms used in user-level RCU might be applied here, but some work is required to handle the NMIs that user-space applications can happily ignore. For the short term, better safe than sorry.) This proof assumes that neither compiler nor CPU will allow a lock acquisition and release to be reordered, as doing so can result in deadlock. The proof is as follows: 1. A given CPU declares a quiescent state under the protection of its leaf rcu_node's lock. 2. If there is more than one level of rcu_node hierarchy, the last CPU to declare a quiescent state will also acquire the ->lock of the next rcu_node up in the hierarchy, but only after releasing the lower level's lock. The acquisition of this lock clearly cannot occur prior to the acquisition of the leaf node's lock. 3. Step 2 repeats until we reach the root rcu_node structure. Please note again that only one lock is held at a time through this process. The acquisition of the root rcu_node's ->lock must occur after the release of that of the leaf rcu_node. 4. At this point, we set the ->completed field in the rcu_state structure in rcu_report_qs_rsp(). However, if the rcu_node hierarchy contains only one rcu_node, then in theory the code preceding the quiescent state could leak into the critical section. We therefore precede the update of ->completed with a memory barrier. All CPUs will therefore agree that any updates preceding any report of a quiescent state will have happened before the update of ->completed. 5. Regardless of whether a new grace period is needed, rcu_start_gp() will propagate the new value of ->completed to all of the leaf rcu_node structures, under the protection of each rcu_node's ->lock. If a new grace period is needed immediately, this propagation will occur in the same critical section that ->completed was set in, but courtesy of the memory barrier in #4 above, is still seen to follow any pre-quiescent-state activity. 6. When a given CPU invokes __rcu_process_gp_end(), it becomes aware of the end of the old grace period and therefore makes any RCU callbacks that were waiting on that grace period eligible for invocation. If this CPU is the same one that detected the end of the grace period, and if there is but a single rcu_node in the hierarchy, we will still be in the single critical section. In this case, the memory barrier in step #4 guarantees that all callbacks will be seen to execute after each CPU's quiescent state. On the other hand, if this is a different CPU, it will acquire the leaf rcu_node's ->lock, and will again be serialized after each CPU's quiescent state for the old grace period. On the strength of this proof, this commit therefore removes the memory barriers from rcu_process_callbacks() and adds one to rcu_report_qs_rsp(). The effect is to reduce the number of memory barriers by one and to reduce the frequency of execution from about once per scheduling tick per CPU to once per grace period. This was reverted do to hangs found during testing by Yinghai Lu and Ingo Molnar. Frederic Weisbecker supplied Yinghai with tracing that located the underlying problem, and Frederic also provided the fix. The underlying problem was that the HARDIRQ_ENTER() macro from lib/locking-selftest.c invoked irq_enter(), which in turn invokes rcu_irq_enter(), but HARDIRQ_EXIT() invoked __irq_exit(), which does not invoke rcu_irq_exit(). This situation resulted in calls to rcu_irq_enter() that were not balanced by the required calls to rcu_irq_exit(). Therefore, after these locking selftests completed, RCU's dyntick-idle nesting count was a large number (for example, 72), which caused RCU to to conclude that the affected CPU was not in dyntick-idle mode when in fact it was. RCU would therefore incorrectly wait for this dyntick-idle CPU, resulting in hangs. In contrast, with Frederic's patch, which replaces the irq_enter() in HARDIRQ_ENTER() with an __irq_enter(), these tests don't ever call either rcu_irq_enter() or rcu_irq_exit(), which works because the CPU running the test is already marked as not being in dyntick-idle mode. This means that the rcu_irq_enter() and rcu_irq_exit() calls and RCU then has no problem working out which CPUs are in dyntick-idle mode and which are not. The reason that the imbalance was not noticed before the barrier patch was applied is that the old implementation of rcu_enter_nohz() ignored the nesting depth. This could still result in delays, but much shorter ones. Whenever there was a delay, RCU would IPI the CPU with the unbalanced nesting level, which would eventually result in rcu_enter_nohz() being called, which in turn would force RCU to see that the CPU was in dyntick-idle mode. The reason that very few people noticed the problem is that the mismatched irq_enter() vs. __irq_exit() occured only when the kernel was built with CONFIG_DEBUG_LOCKING_API_SELFTESTS. Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com> Reviewed-by: Josh Triplett <josh@joshtriplett.org>
| * | | | | Documentation: Add statistics about nested locksJuri Lelli2011-05-281-2/+34
| | |/ / / | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Explain what the trailing "/1" on some lock class names of lock_stat output means. Reviewed-by: Yong Zhang <yong.zhang0@gmail.com> Signed-off-by: Juri Lelli <juri.lelli@gmail.com> Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Link: http://lkml.kernel.org/r/4DD4F6C1.5090701@gmail.com Signed-off-by: Ingo Molnar <mingo@elte.hu>
* | | | | Merge branch 'next' of ↵Linus Torvalds2011-05-281-1/+96
|\ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx * 'next' of git://git.kernel.org/pub/scm/linux/kernel/git/djbw/async_tx: (33 commits) x86: poll waiting for I/OAT DMA channel status maintainers: add dma engine tree details dmaengine: add TODO items for future work on dma drivers dmaengine: Add API documentation for slave dma usage dmaengine/dw_dmac: Update maintainer-ship dmaengine: move link order dmaengine/dw_dmac: implement pause and resume in dwc_control dmaengine/dw_dmac: Replace spin_lock* with irqsave variants and enable submission from callback dmaengine/dw_dmac: Divide one sg to many desc, if sg len is greater than DWC_MAX_COUNT dmaengine/dw_dmac: set residue as total len in dwc_tx_status if status is !DMA_SUCCESS dmaengine/dw_dmac: don't call callback routine in case dmaengine_terminate_all() is called dmaengine: at_hdmac: pause: no need to wait for FIFO empty pch_dma: modify pci device table definition pch_dma: Support new device ML7223 IOH pch_dma: Support I2S for ML7213 IOH pch_dma: Fix DMA setting issue pch_dma: modify for checkpatch pch_dma: fix dma direction issue for ML7213 IOH video-in dmaengine: at_hdmac: use descriptor chaining help function dmaengine: at_hdmac: implement pause and resume in atc_control ... Fix up trivial conflict in drivers/dma/dw_dmac.c
| * | | | | dmaengine: Add API documentation for slave dma usageVinod Koul2011-05-251-1/+96
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Vinod Koul <vinod.koul@intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com>
* | | | | | Merge git://git.infradead.org/mtd-2.6Linus Torvalds2011-05-271-2/+1
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.infradead.org/mtd-2.6: (97 commits) mtd: kill CONFIG_MTD_PARTITIONS mtd: remove add_mtd_partitions, add_mtd_device and friends mtd: convert remaining users to mtd_device_register() mtd: samsung onenand: convert to mtd_device_register() mtd: omap2 onenand: convert to mtd_device_register() mtd: txx9ndfmc: convert to mtd_device_register() mtd: tmio_nand: convert to mtd_device_register() mtd: socrates_nand: convert to mtd_device_register() mtd: sharpsl: convert to mtd_device_register() mtd: s3c2410 nand: convert to mtd_device_register() mtd: ppchameleonevb: convert to mtd_device_register() mtd: orion_nand: convert to mtd_device_register() mtd: omap2: convert to mtd_device_register() mtd: nomadik_nand: convert to mtd_device_register() mtd: ndfc: convert to mtd_device_register() mtd: mxc_nand: convert to mtd_device_register() mtd: mpc5121_nfc: convert to mtd_device_register() mtd: jz4740_nand: convert to mtd_device_register() mtd: h1910: convert to mtd_device_register() mtd: fsmc_nand: convert to mtd_device_register() ... Fixed up trivial conflicts in - drivers/mtd/maps/integrator-flash.c: removed in ARM tree - drivers/mtd/maps/physmap.c: addition of afs partition probe type clashing with removal of CONFIG_MTD_PARTITIONS
| * | | | | | mtd: kill CONFIG_MTD_PARTITIONSJamie Iles2011-05-251-2/+1
| | |_|_|_|/ | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Now that none of the drivers use CONFIG_MTD_PARTITIONS we can remove it from Kconfig and the last remaining uses. Signed-off-by: Jamie Iles <jamie@jamieiles.com> Signed-off-by: Artem Bityutskiy <Artem.Bityutskiy@nokia.com> Signed-off-by: David Woodhouse <David.Woodhouse@intel.com>
* | | | | | Merge git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6Linus Torvalds2011-05-271-0/+14
|\ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-misc-2.6: (60 commits) [SCSI] lpfc 8.3.24: Extend BSG infrastructure and add link diagnostics [SCSI] lpfc 8.3.24: Add resource extent support [SCSI] lpfc 8.3.24: Add request-firmware support [SCSI] lpfc 8.3.24: Add SR-IOV control [SCSI] lpfc 8.3.24: Extended hardware support and support dump images [SCSI] lpfc 8.3.24: Miscellaneous Fixes and Corrections [SCSI] libsas: Add option for SATA soft reset [SCSI] libsas: check dev->gone before submitting sata i/o [SCSI] libsas: fix/amend device gone notification in sas_deform_port() [SCSI] MAINTAINERS update for SCSI (new email address) [SCSI] Fix Ultrastor asm snippet [SCSI] osst: fix warning [SCSI] osst: wrong index used in inner loop [SCSI] aic94xx: world-writable sysfs update_bios file [SCSI] MAINTAINERS: Add drivers/target/ entry [SCSI] target: Convert TASK_ATTR to scsi_tcq.h definitions [SCSI] target: Convert REPORT_LUNs to use int_to_scsilun [SCSI] target: Fix task->task_execute_queue=1 clear bug + LUN_RESET OOPs [SCSI] target: Fix bug with task_sg chained transport_free_dev_tasks release [SCSI] target: Fix interrupt context bug with stats_lock and core_tmr_alloc_req ...
| * | | | | | [SCSI] megaraid_sas: Version and Changelog updateadam radford2011-05-241-0/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Adam Radford <aradford@gmail.com> Signed-off-by: James Bottomley <jbottomley@parallels.com>
* | | | | | | Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-armLinus Torvalds2011-05-273-10/+73
|\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | * 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (45 commits) ARM: 6945/1: Add unwinding support for division functions ARM: kill pmd_off() ARM: 6944/1: mm: allow ASID 0 to be allocated to tasks ARM: 6943/1: mm: use TTBR1 instead of reserved context ID ARM: 6942/1: mm: make TTBR1 always point to swapper_pg_dir on ARMv6/7 ARM: 6941/1: cache: ensure MVA is cacheline aligned in flush_kern_dcache_area ARM: add sendmmsg syscall ARM: 6863/1: allow hotplug on msm ARM: 6832/1: mmci: support for ST-Ericsson db8500v2 ARM: 6830/1: mach-ux500: force PrimeCell revisions ARM: 6829/1: amba: make hardcoded periphid override hardware ARM: 6828/1: mach-ux500: delete SSP PrimeCell ID ARM: 6827/1: mach-netx: delete hardcoded periphid ARM: 6940/1: fiq: Briefly document driver responsibilities for suspend/resume ARM: 6938/1: fiq: Refactor {get,set}_fiq_regs() for Thumb-2 ARM: 6914/1: sparsemem: fix highmem detection when using SPARSEMEM ARM: 6913/1: sparsemem: allow pfn_valid to be overridden when using SPARSEMEM at91: drop at572d940hf support at91rm9200: introduce at91rm9200_set_type to specficy cpu package at91: drop boot_params and PLAT_PHYS_OFFSET ...
| * \ \ \ \ \ \ Merge branches 'devel', 'devel-stable' and 'fixes' into for-linusRussell King2011-05-273-10/+73
| |\ \ \ \ \ \ \
| | * \ \ \ \ \ \ Merge branch 'for-rmk' of git://github.com/at91linux/linux-2.6-at91 into ↵Russell King2011-05-268-49/+184
| | |\ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | devel-stable
| | * \ \ \ \ \ \ \ Merge branch 'for-rmk' of ↵Russell King2011-05-251-2/+0
| | |\ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/kgene/linux-samsung into devel-stable Conflicts: arch/arm/Kconfig arch/arm/mach-exynos4/mach-nuri.c
| | | * | | | | | | | ARM: S5P6442: Removing ARCH_S5P6442Kukjin Kim2011-05-121-2/+0
| | | | |_|/ / / / / | | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | Signed-off-by: Kukjin Kim <kgene.kim@samsung.com>
| | * | | | | | | | Merge branch 'devicetree/arm-next' of git://git.secretlab.ca/git/linux-2.6 ↵Russell King2011-05-252-8/+73
| | |\ \ \ \ \ \ \ \ | | | |_|_|/ / / / / | | |/| | | | | | | | | | | | | | | | | into devel-stable
| | | * | | | | | | dt: add documentation of ARM dt boot interfaceGrant Likely2011-05-232-8/+73
| | | |/ / / / / / | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | v6: typo fixes v5: clarified that dtb should be aligned on a 64 bit boundary in RAM. v3: added details to Documentation/arm/Booting Acked-by: Tony Lindgren <tony@atomide.com> Acked-by: Nicolas Pitre <nicolas.pitre@linaro.org> Acked-by: Russell King <rmk+kernel@arm.linux.org.uk> Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
* | | | | | | | | Merge branch 'docs-move' of ↵Linus Torvalds2011-05-2712-13/+29
|\ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs * 'docs-move' of git://git.kernel.org/pub/scm/linux/kernel/git/rdunlap/linux-docs: Create Documentation/security/, move LSM-, credentials-, and keys-related files from Documentation/ to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/<moved_file> to Documentation/security/<moved_file>.
| * \ \ \ \ \ \ \ \ Merge branch 'docs-security' into docs-moveRandy Dunlap2011-05-2012-13/+29
| |\ \ \ \ \ \ \ \ \
| | * | | | | | | | | Create Documentation/security/,Randy Dunlap2011-05-1912-13/+29
| | | |_|/ / / / / / | | |/| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | move LSM-, credentials-, and keys-related files from Documentation/ to Documentation/security/, add Documentation/security/00-INDEX, and update all occurrences of Documentation/<moved_file> to Documentation/security/<moved_file>.
* | | | | | | | | | Merge branch 'v4l_for_linus' of ↵Linus Torvalds2011-05-275-12/+17
|\ \ \ \ \ \ \ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6 * 'v4l_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mchehab/linux-2.6: [media] v1.88 DM04/QQBOX Move remote to use rc_core dvb-usb-remote [media] Add missing include guard to header file [media] Inlined functions should be static [media] Remove invalid parameter description [media] cpia2: fix warning about invalid trigraph sequence [media] s5p-csis: Add missing dependency on PLAT_S5P [media] gspca/kinect: wrap gspca_debug with GSPCA_DEBUG [media] fintek-cir: new driver for Fintek LPC SuperIO CIR function [media] uvcvideo: Connect video devices to media entities [media] uvcvideo: Register subdevices for each entity [media] uvcvideo: Register a v4l2_device [media] add V4L2-PIX-FMT-SRGGB12 & friends to docbook [media] Documentation/DocBook: Rename media fops xml files [media] Media DocBook: fix validation errors [media] wl12xx: g_volatile_ctrl fix: wrong field set [media] fix kconfig dependency warning for VIDEO_TIMBERDALE [media] dm1105: GPIO handling added, I2C on GPIO added, LNB control through GPIO reworked [media] Add support for M-5MOLS 8 Mega Pixel camera ISP
| * | | | | | | | | | [media] add V4L2-PIX-FMT-SRGGB12 & friends to docbookMauro Carvalho Chehab2011-05-252-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The xml with those guys are there, but they weren't included on the docbook. Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
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