summaryrefslogtreecommitdiffstats
path: root/kernel
AgeCommit message (Collapse)AuthorFilesLines
2013-09-03Merge branch 'for-3.12' of ↵Linus Torvalds7-1066/+1246
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup updates from Tejun Heo: "A lot of activities on the cgroup front. Most changes aren't visible to userland at all at this point and are laying foundation for the planned unified hierarchy. - The biggest change is decoupling the lifetime management of css (cgroup_subsys_state) from that of cgroup's. Because controllers (cpu, memory, block and so on) will need to be dynamically enabled and disabled, css which is the association point between a cgroup and a controller may come and go dynamically across the lifetime of a cgroup. Till now, css's were created when the associated cgroup was created and stayed till the cgroup got destroyed. Assumptions around this tight coupling permeated through cgroup core and controllers. These assumptions are gradually removed, which consists bulk of patches, and css destruction path is completely decoupled from cgroup destruction path. Note that decoupling of creation path is relatively easy on top of these changes and the patchset is pending for the next window. - cgroup has its own event mechanism cgroup.event_control, which is only used by memcg. It is overly complex trying to achieve high flexibility whose benefits seem dubious at best. Going forward, new events will simply generate file modified event and the existing mechanism is being made specific to memcg. This pull request contains prepatory patches for such change. - Various fixes and cleanups" Fixed up conflict in kernel/cgroup.c as per Tejun. * 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: (69 commits) cgroup: fix cgroup_css() invocation in css_from_id() cgroup: make cgroup_write_event_control() use css_from_dir() instead of __d_cgrp() cgroup: make cgroup_event hold onto cgroup_subsys_state instead of cgroup cgroup: implement CFTYPE_NO_PREFIX cgroup: make cgroup_css() take cgroup_subsys * instead and allow NULL subsys cgroup: rename cgroup_css_from_dir() to css_from_dir() and update its syntax cgroup: fix cgroup_write_event_control() cgroup: fix subsystem file accesses on the root cgroup cgroup: change cgroup_from_id() to css_from_id() cgroup: use css_get() in cgroup_create() to check CSS_ROOT cpuset: remove an unncessary forward declaration cgroup: RCU protect each cgroup_subsys_state release cgroup: move subsys file removal to kill_css() cgroup: factor out kill_css() cgroup: decouple cgroup_subsys_state destruction from cgroup destruction cgroup: replace cgroup->css_kill_cnt with ->nr_css cgroup: bounce cgroup_subsys_state ref kill confirmation to a work item cgroup: move cgroup->subsys[] assignment to online_css() cgroup: reorganize css init / exit paths cgroup: add __rcu modifier to cgroup->subsys[] ...
2013-09-03Merge branch 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wqLinus Torvalds1-5/+9
Pull workqueue updates from Tejun Heo: "Nothing interesting. All are doc / comment updates" * 'for-3.12' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/wq: workqueue: Correct/Drop references to gcwq in Documentation workqueue: Fix manage_workers() RETURNS description workqueue: Comment correction in file header workqueue: mark WQ_NON_REENTRANT deprecated
2013-09-03Merge tag 'pm+acpi-3.12-rc1' of ↵Linus Torvalds2-8/+5
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull ACPI and power management updates from Rafael Wysocki: 1) ACPI-based PCI hotplug (ACPIPHP) subsystem rework and introduction of Intel Thunderbolt support on systems that use ACPI for signalling Thunderbolt hotplug events. This also should make ACPIPHP work in some cases in which it was known to have problems. From Rafael J Wysocki, Mika Westerberg and Kirill A Shutemov. 2) ACPI core code cleanups and dock station support cleanups from Jiang Liu and Rafael J Wysocki. 3) Fixes for locking problems related to ACPI device hotplug from Rafael J Wysocki. 4) ACPICA update to version 20130725 includig fixes, cleanups, support for more than 256 GPEs per GPE block and a change to make the ACPI PM Timer optional (we've seen systems without the PM Timer in the field already). One of the fixes, related to the DeRefOf operator, is necessary to prevent some Windows 8 oriented AML from causing problems to happen. From Bob Moore, Lv Zheng, and Jung-uk Kim. 5) Removal of the old and long deprecated /proc/acpi/event interface and related driver changes from Thomas Renninger. 6) ACPI and Xen changes to make the reduced hardware sleep work with the latter from Ben Guthro. 7) ACPI video driver cleanups and a blacklist of systems that should not tell the BIOS that they are compatible with Windows 8 (or ACPI backlight and possibly other things will not work on them). From Felipe Contreras. 8) Assorted ACPI fixes and cleanups from Aaron Lu, Hanjun Guo, Kuppuswamy Sathyanarayanan, Lan Tianyu, Sachin Kamat, Tang Chen, Toshi Kani, and Wei Yongjun. 9) cpufreq ondemand governor target frequency selection change to reduce oscillations between min and max frequencies (essentially, it causes the governor to choose target frequencies proportional to load) from Stratos Karafotis. 10) cpufreq fixes allowing sysfs attributes file permissions to be preserved over suspend/resume cycles Srivatsa S Bhat. 11) Removal of Device Tree parsing for CPU device nodes from multiple cpufreq drivers that required some changes related to of_get_cpu_node() to be made in a few architectures and in the driver core. From Sudeep KarkadaNagesha. 12) cpufreq core fixes and cleanups related to mutual exclusion and driver module references from Viresh Kumar, Lukasz Majewski and Rafael J Wysocki. 13) Assorted cpufreq fixes and cleanups from Amit Daniel Kachhap, Bartlomiej Zolnierkiewicz, Hanjun Guo, Jingoo Han, Joseph Lo, Julia Lawall, Li Zhong, Mark Brown, Sascha Hauer, Stephen Boyd, Stratos Karafotis, and Viresh Kumar. 14) Fixes to prevent race conditions in coupled cpuidle from happening from Colin Cross. 15) cpuidle core fixes and cleanups from Daniel Lezcano and Tuukka Tikkanen. 16) Assorted cpuidle fixes and cleanups from Daniel Lezcano, Geert Uytterhoeven, Jingoo Han, Julia Lawall, Linus Walleij, and Sahara. 17) System sleep tracing changes from Todd E Brandt and Shuah Khan. 18) PNP subsystem conversion to using struct dev_pm_ops for power management from Shuah Khan. * tag 'pm+acpi-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: (217 commits) cpufreq: Don't use smp_processor_id() in preemptible context cpuidle: coupled: fix race condition between pokes and safe state cpuidle: coupled: abort idle if pokes are pending cpuidle: coupled: disable interrupts after entering safe state ACPI / hotplug: Remove containers synchronously driver core / ACPI: Avoid device hot remove locking issues cpufreq: governor: Fix typos in comments cpufreq: governors: Remove duplicate check of target freq in supported range cpufreq: Fix timer/workqueue corruption due to double queueing ACPI / EC: Add ASUSTEK L4R to quirk list in order to validate ECDT ACPI / thermal: Add check of "_TZD" availability and evaluating result cpufreq: imx6q: Fix clock enable balance ACPI: blacklist win8 OSI for buggy laptops cpufreq: tegra: fix the wrong clock name cpuidle: Change struct menu_device field types cpuidle: Add a comment warning about possible overflow cpuidle: Fix variable domains in get_typical_interval() cpuidle: Fix menu_device->intervals type cpuidle: CodingStyle: Break up multiple assignments on single line cpuidle: Check called function parameter in get_typical_interval() ...
2013-09-03Merge tag 'tty-3.12-rc1' of ↵Linus Torvalds1-0/+7
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty Pull tty/serial driver patches from Greg KH: "Here's the big tty/serial driver pull request for 3.12-rc1. Lots of n_tty reworks to resolve some very long-standing issues, removing the 3-4 different locks that were taken for every character. This code has been beaten on for a long time in linux-next with no reported regressions. Other than that, a range of serial and tty driver updates and revisions. Full details in the shortlog" * tag 'tty-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/tty: (226 commits) hvc_xen: Remove unnecessary __GFP_ZERO from kzalloc serial: imx: initialize the local variable tty: ar933x_uart: add device tree support and binding documentation tty: ar933x_uart: allow to build the driver as a module ARM: dts: msm: Update uartdm compatible strings devicetree: serial: Document msm_serial bindings serial: unify serial bindings into a single dir serial: fsl-imx-uart: Cleanup duplicate device tree binding tty: ar933x_uart: use config_enabled() macro to clean up ifdefs tty: ar933x_uart: remove superfluous assignment of ar933x_uart_driver.nr tty: ar933x_uart: use the clk API to get the uart clock tty: serial: cpm_uart: Adding proper request of GPIO used by cpm_uart driver serial: sirf: fix the amount of serial ports serial: sirf: define macro for some magic numbers of USP serial: icom: move array overflow checks earlier TTY: amiserial, remove unnecessary platform_set_drvdata() serial: st-asc: remove unnecessary platform_set_drvdata() msm_serial: Send more than 1 character on the console w/ UARTDM msm_serial: Add support for non-GSBI UARTDM devices msm_serial: Switch clock consumer strings and simplify code ...
2013-09-03Merge tag 'driver-core-3.12-rc1' of ↵Linus Torvalds1-12/+15
git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core Pull driver core patches from Greg KH: "Here's the big driver core pull request for 3.12-rc1. Lots of tiny changes here fixing up the way sysfs attributes are created, to try to make drivers simpler, and fix a whole class race conditions with creations of device attributes after the device was announced to userspace. All the various pieces are acked by the different subsystem maintainers" * tag 'driver-core-3.12-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (119 commits) firmware loader: fix pending_fw_head list corruption drivers/base/memory.c: introduce help macro to_memory_block dynamic debug: line queries failing due to uninitialized local variable sysfs: sysfs_create_groups returns a value. debugfs: provide debugfs_create_x64() when disabled rbd: convert bus code to use bus_groups firmware: dcdbas: use binary attribute groups sysfs: add sysfs_create/remove_groups for when SYSFS is not enabled driver core: add #include <linux/sysfs.h> to core files. HID: convert bus code to use dev_groups Input: serio: convert bus code to use drv_groups Input: gameport: convert bus code to use drv_groups driver core: firmware: use __ATTR_RW() driver core: core: use DEVICE_ATTR_RO driver core: bus: use DRIVER_ATTR_WO() driver core: create write-only attribute macros for devices and drivers sysfs: create __ATTR_WO() driver-core: platform: convert bus code to use dev_groups workqueue: convert bus code to use dev_groups MEI: convert bus code to use dev_groups ...
2013-08-30Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/netLinus Torvalds3-17/+19
Pull networking fixes from David Miller: 1) There was a simplification in the ipv6 ndisc packet sending attempted here, which avoided using memory accounting on the per-netns ndisc socket for sending NDISC packets. It did fix some important issues, but it causes regressions so it gets reverted here too. Specifically, the problem with this change is that the IPV6 output path really depends upon there being a valid skb->sk attached. The reason we want to do this change in some form when we figure out how to do it right, is that if a device goes down the ndisc_sk socket send queue will fill up and block NDISC packets that we want to send to other devices too. That's really bad behavior. Hopefully Thomas can come up with a better version of this change. 2) Fix a severe TCP performance regression by reverting a change made to dev_pick_tx() quite some time ago. From Eric Dumazet. 3) TIPC returns wrongly signed error codes, fix from Erik Hugne. 4) Fix OOPS when doing IPSEC over ipv4 tunnels due to orphaning the skb->sk too early. Fix from Li Hongjun. 5) RAW ipv4 sockets can use the wrong routing key during lookup, from Chris Clark. 6) Similar to #1 revert an older change that tried to use plain alloc_skb() for SYN/ACK TCP packets, this broke the netfilter owner mark which needs to see the skb->sk for such frames. From Phil Oester. 7) BNX2x driver bug fixes from Ariel Elior and Yuval Mintz, specifically in the handling of virtual functions. 8) IPSEC path error propagations to sockets is not done properly when we have v4 in v6, and v6 in v4 type rules. Fix from Hannes Frederic Sowa. 9) Fix missing channel context release in mac80211, from Johannes Berg. 10) Fix network namespace handing wrt. SCM_RIGHTS, from Andy Lutomirski. 11) Fix usage of bogus NAPI weight in jme, netxen, and ps3_gelic drivers. From Michal Schmidt. 12) Hopefully a complete and correct fix for the genetlink dump locking and module reference counting. From Pravin B Shelar. 13) sk_busy_loop() must do a cpu_relax(), from Eliezer Tamir. 14) Fix handling of timestamp offset when restoring a snapshotted TCP socket. From Andrew Vagin. * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net: (44 commits) net: fec: fix time stamping logic after napi conversion net: bridge: convert MLDv2 Query MRC into msecs_to_jiffies for max_delay mISDN: return -EINVAL on error in dsp_control_req() net: revert 8728c544a9c ("net: dev_pick_tx() fix") Revert "ipv6: Don't depend on per socket memory for neighbour discovery messages" ipv4 tunnels: fix an oops when using ipip/sit with IPsec tipc: set sk_err correctly when connection fails tcp: tcp_make_synack() should use sock_wmalloc bridge: separate querier and query timer into IGMP/IPv4 and MLD/IPv6 ones ipv6: Don't depend on per socket memory for neighbour discovery messages ipv4: sendto/hdrincl: don't use destination address found in header tcp: don't apply tsoffset if rcv_tsecr is zero tcp: initialize rcv_tstamp for restored sockets net: xilinx: fix memleak net: usb: Add HP hs2434 device to ZLP exception table net: add cpu_relax to busy poll loop net: stmmac: fixed the pbl setting with DT genl: Hold reference on correct module while netlink-dump. genl: Fix genl dumpit() locking. xfrm: Fix potential null pointer dereference in xdst_queue_output ...
2013-08-29Merge branch 'for-3.11-fixes' of ↵Linus Torvalds1-1/+18
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fix from Tejun Heo: "During the percpu reference counting update which was merged during v3.11-rc1, the cgroup destruction path was updated so that a cgroup in the process of dying may linger on the children list, which was necessary as the cgroup should still be included in child/descendant iteration while percpu ref is being killed. Unfortunately, I forgot to update cgroup destruction path accordingly and cgroup destruction may fail spuriously with -EBUSY due to lingering dying children even when there's no live child left - e.g. "rmdir parent/child parent" will usually fail. This can be easily fixed by iterating through the children list to verify that there's no live child left. While this is very late in the release cycle, this bug is very visible to userland and I believe the fix is relatively safe. Thanks Hugh for spotting and providing fix for the issue" * 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cgroup: fix rmdir EBUSY regression in 3.11
2013-08-29cgroup: fix rmdir EBUSY regression in 3.11Hugh Dickins1-1/+18
On 3.11-rc we are seeing cgroup directories left behind when they should have been removed. Here's a trivial reproducer: cd /sys/fs/cgroup/memory mkdir parent parent/child; rmdir parent/child parent rmdir: failed to remove `parent': Device or resource busy It's because cgroup_destroy_locked() (step 1 of destruction) leaves cgroup on parent's children list, letting cgroup_offline_fn() (step 2 of destruction) remove it; but step 2 is run by work queue, which may not yet have removed the children when parent destruction checks the list. Fix that by checking through a non-empty list of children: if every one of them has already been marked CGRP_DEAD, then it's safe to proceed: those children are invisible to userspace, and should not obstruct rmdir. (I didn't see any reason to keep the cgrp->children checks under the unrelated css_set_lock, so moved them out.) tj: Flattened nested ifs a bit and updated comment so that it's correct on both for-3.11-fixes and for-3.12. Signed-off-by: Hugh Dickins <hughd@google.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-29workqueue: cond_resched() after processing each work itemTejun Heo1-0/+9
If !PREEMPT, a kworker running work items back to back can hog CPU. This becomes dangerous when a self-requeueing work item which is waiting for something to happen races against stop_machine. Such self-requeueing work item would requeue itself indefinitely hogging the kworker and CPU it's running on while stop_machine would wait for that CPU to enter stop_machine while preventing anything else from happening on all other CPUs. The two would deadlock. Jamie Liu reports that this deadlock scenario exists around scsi_requeue_run_queue() and libata port multiplier support, where one port may exclude command processing from other ports. With the right timing, scsi_requeue_run_queue() can end up requeueing itself trying to execute an IO which is asked to be retried while another device has an exclusive access, which in turn can't make forward progress due to stop_machine. Fix it by invoking cond_resched() after executing each work item. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Jamie Liu <jamieliu@google.com> References: http://thread.gmane.org/gmane.linux.kernel/1552567 Cc: stable@vger.kernel.org -- kernel/workqueue.c | 9 +++++++++ 1 file changed, 9 insertions(+)
2013-08-28timer_list: correct the iterator for timer_listNathan Zimmer1-17/+24
Correct an issue with /proc/timer_list reported by Holger. When reading from the proc file with a sufficiently small buffer, 2k so not really that small, there was one could get hung trying to read the file a chunk at a time. The timer_list_start function failed to account for the possibility that the offset was adjusted outside the timer_list_next. Signed-off-by: Nathan Zimmer <nzimmer@sgi.com> Reported-by: Holger Hans Peter Freyther <holger@freyther.de> Cc: John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Berke Durak <berke.durak@xiphos.com> Cc: Jeff Layton <jlayton@redhat.com> Tested-by: Al Viro <viro@zeniv.linux.org.uk> Cc: <stable@vger.kernel.org> # 3.10.x Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-27cgroup: fix cgroup_css() invocation in css_from_id()Tejun Heo1-1/+1
ca8bdcaff0 ("cgroup: make cgroup_css() take cgroup_subsys * instead and allow NULL subsys") missed one conversion in css_from_id(), which was newly added. As css_from_id() doesn't have any user yet, this doesn't break anything other than generating a build warning. Convert it. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Stephen Rothwell <sfr@canb.auug.org.au> Reported-by: kbuild test robot <fengguang.wu@intel.com>
2013-08-27Rename nsproxy.pid_ns to nsproxy.pid_ns_for_childrenAndy Lutomirski3-17/+19
nsproxy.pid_ns is *not* the task's pid namespace. The name should clarify that. This makes it more obvious that setns on a pid namespace is weird -- it won't change the pid namespace shown in procfs. Signed-off-by: Andy Lutomirski <luto@amacapital.net> Reviewed-by: "Eric W. Biederman" <ebiederm@xmission.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2013-08-27Merge branch 'pm-sleep'Rafael J. Wysocki1-2/+2
* pm-sleep: PM / Sleep: new trace event to print device suspend and resume times PM / Sleep: increase ftrace coverage in suspend/resume
2013-08-27Merge branch 'acpi-processor'Rafael J. Wysocki1-6/+3
* acpi-processor: ACPI / processor: Acquire writer lock to update CPU maps ACPI / processor: Remove acpi_processor_get_limit_info()
2013-08-26cgroup: make cgroup_write_event_control() use css_from_dir() instead of ↵Tejun Heo1-13/+5
__d_cgrp() cgroup_event will be moved to its only user - memcg. Replace __d_cgrp() usage with css_from_dir(), which is already exported. This also simplifies the code a bit. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
2013-08-26cgroup: make cgroup_event hold onto cgroup_subsys_state instead of cgroupTejun Heo1-14/+12
Currently, each registered cgroup_event holds an extra reference to the cgroup. This is a bit weird as events are subsystem specific and will also be incorrect in the planned unified hierarchy as css (cgroup_subsys_state) may come and go dynamically across the lifetime of a cgroup. Holding onto cgroup won't prevent the target css from going away. Update cgroup_event to hold onto the css the traget file belongs to instead of cgroup. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
2013-08-26cgroup: implement CFTYPE_NO_PREFIXTejun Heo1-1/+2
When cgroup files are created, cgroup core automatically prepends the name of the subsystem as prefix. This patch adds CFTYPE_NO_ which disables the automatic prefix. This is to work around historical baggages and shouldn't be used for new files. This will be used to move "cgroup.event_control" from cgroup core to memcg. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Glauber Costa <glommer@gmail.com>
2013-08-26cgroup: make cgroup_css() take cgroup_subsys * instead and allow NULL subsysTejun Heo1-47/+43
cgroup_css() is no longer used in hot paths. Make it take struct cgroup_subsys * and allow the users to specify NULL subsys to obtain the dummy_css. This removes open-coded NULL subsystem testing in a couple users and generally simplifies the code. After this patch, css_from_dir() also allows NULL @ss and returns the matching dummy_css. This behavior change doesn't affect its only user - perf. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
2013-08-26cgroup: rename cgroup_css_from_dir() to css_from_dir() and update its syntaxTejun Heo2-17/+11
cgroup_css_from_dir() will grow another user. In preparation, make the following changes. * All css functions are prefixed with just "css_", rename it to css_from_dir(). * Take dentry * instead of file * as dentry is what ultimately identifies a cgroup and file may not always be available. Note that the function now checkes whether @dentry->d_inode is NULL as the caller now may specify a negative dentry. * Make it take cgroup_subsys * instead of integer subsys_id. This simplifies the function and allows specifying no subsystem for cgroup->dummy_css. * Make return section a bit less verbose. This patch doesn't introduce any behavior changes. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com>
2013-08-23workqueue: convert bus code to use dev_groupsGreg Kroah-Hartman1-12/+15
The dev_attrs field of struct bus_type is going away soon, dev_groups should be used instead. This converts the workqueue bus code to use the correct field. Acked-by: Tejun Heo <tj@kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2013-08-23Merge branch 'for-3.11-fixes' of ↵Linus Torvalds1-5/+9
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fix from Tejun Heo: "A late fix for cgroup. This fixes a behavior regression visible to userland which was created by a commit merged during -rc1. While the behavior change isn't too likely to be noticeable, the fix is relatively low risk and we'll need to backport it through -stable anyway if the bug gets released" * 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cpuset: fix a regression in validating config change
2013-08-21workqueue: Fix manage_workers() RETURNS descriptionLibin1-2/+5
No functional change. The comment of function manage_workers() RETURNS description is obvious wrong, same as the CONTEXT. Fix it. Signed-off-by: Libin <huawei.libin@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-21workqueue: Comment correction in file headerLibin1-3/+4
No functional change. There are two worker pools for each cpu in current implementation (one for normal work items and the other for high priority ones). tj: Whitespace adjustments. Signed-off-by: Libin <huawei.libin@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-21cpuset: fix a regression in validating config changeLi Zefan1-5/+9
It's not allowed to clear masks of a cpuset if there're tasks in it, but it's broken: # mkdir /cgroup/sub # echo 0 > /cgroup/sub/cpuset.cpus # echo 0 > /cgroup/sub/cpuset.mems # echo $$ > /cgroup/sub/tasks # echo > /cgroup/sub/cpuset.cpus (should fail) This bug was introduced by commit 88fa523bff295f1d60244a54833480b02f775152 ("cpuset: allow to move tasks to empty cpusets"). tj: Dropped temp bool variables and nestes the conditionals directly. Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-19Merge branch 'timers-urgent-for-linus' of ↵Linus Torvalds2-4/+3
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull timer fixes from Ingo Molnar: "Three small fixlets" * 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: nohz: fix compile warning in tick_nohz_init() nohz: Do not warn about unstable tsc unless user uses nohz_full sched_clock: Fix integer overflow
2013-08-19kernel: fix new kernel-doc warning in wait.cRandy Dunlap1-2/+1
Fix new kernel-doc warnings in kernel/wait.c: Warning(kernel/wait.c:374): No description found for parameter 'p' Warning(kernel/wait.c:374): Excess function parameter 'word' description in 'wake_up_atomic_t' Warning(kernel/wait.c:374): Excess function parameter 'bit' description in 'wake_up_atomic_t' Signed-off-by: Randy Dunlap <rdunlap@infradead.org> Cc: David Howells <dhowells@redhat.com> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-19cgroup: fix cgroup_write_event_control()Tejun Heo1-4/+21
81eeaf0411 ("cgroup: make cftype->[un]register_event() deal with cgroup_subsys_state inst ead of cgroup") updated the cftype event methods to take @css (cgroup_subsys_state) instead of @cgroup; however, it incorrectly used @css passed to cgroup_write_event_control(), which the dummy_css for the cgroup as the file is a cgroup core file. This leads to oops on event registration. Fix it by using the css matching the event target file. Note that cgroup_write_event_control() now disallows cgroup core files from being event sources. This is for simplicity and doesn't matter as cgroup_event will be moved and made specific to memcg. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-19cgroup: fix subsystem file accesses on the root cgroupTejun Heo1-14/+10
105347ba5 ("cgroup: make cgroup_file_open() rcu_read_lock() around cgroup_css() and add cfent->css") added cfent->css to cache the associted cgroup_subsys_state across file operations. A cfent is associated with single css throughout its lifetime and the origimal commit initialized the cache pointer during cgroup_add_file() and verified that it matches the actual one in cgroup_file_open(). While this works fine for !root cgroups, it's broken for root cgroups as files in a root cgroup are created before the css's are associated with the cgroup and thus cgroup_css() call in cgroup_add_file() returns NULL associating all cfents in the root cgroup with NULL css. This makes cgroup_file_open() trigger WARN and fail with -ENODEV for all !core subsystem files in the root cgroups. There's no reason to initialize cfent->css separately from cgroup_add_file(). As the association never changes, cgroup_file_open() can set it unconditionally every time and containing the logic in cgroup_file_open() makes more sense anyway as the only reason it's necessary is file->private_data being already occupied. Fix it by setting cfent->css unconditionally from cgroup_file_open(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-19cgroup: change cgroup_from_id() to css_from_id()Li Zefan1-0/+22
Now we want cgroup core to always provide the css to use to the subsystems, so change this API to css_from_id(). Uninline css_from_id(), because it's getting bigger and cgroup_css() has been unexported. While at it, remove the #ifdef, and shuffle the order of the args. Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-18Merge branch 'for-3.11-fixes' of ↵Linus Torvalds1-2/+4
git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup Pull cgroup fix from Tejun Heo: "This contains one patch to fix the return value of cpuset's cgroups interface function, which used to always return -ENODEV for the writes on the 'memory_pressure_enabled' file" * 'for-3.11-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup: cpuset: fix the return value of cpuset_write_u64()
2013-08-16Merge tag 'pm-3.11-rc6' of ↵Linus Torvalds1-7/+13
git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm Pull power management fix from Rafael Wysocki: "The removal of delayed_work_pending() checks from kernel/power/qos.c done in 3.9 introduced a deadlock in pm_qos_work_fn(). Fix from Stephen Boyd" * tag 'pm-3.11-rc6' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / QoS: Fix workqueue deadlock when using pm_qos_update_request_timeout()
2013-08-16cgroup: use css_get() in cgroup_create() to check CSS_ROOTLi Zhong1-1/+1
It seems that the root css doesn't have refcnt allocated(not needed?), and would cause the booting error attached. This patch tries to use css_get() to not increase the refcnt if parent is root. BUG: unable to handle kernel NULL pointer dereference at (null) IP: [<ffffffff810b37cc>] cgroup_mkdir+0x37c/0x740 PGD 0 Oops: 0002 [#1] Modules linked in: CPU: 0 PID: 1 Comm: systemd Not tainted 3.11.0-rc5-next-20130815+ #1 Hardware name: Bochs Bochs, BIOS Bochs 01/01/2007 task: ffff88007f868000 ti: ffff88007f864000 task.ti: ffff88007f864000 RIP: 0010:[<ffffffff810b37cc>] [<ffffffff810b37cc>] cgroup_mkdir+0x37c/0x740 RSP: 0018:ffff88007f865df8 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffffffff81a46ee0 RCX: 0000000000000001 RDX: 0000000000000000 RSI: 0000000000000000 RDI: ffffffff81a415c0 RBP: ffff88007f865ec8 R08: 0000000000000001 R09: 0000000000000000 R10: ffff88007ce6d060 R11: 0000000000000000 R12: ffff88007ce6d000 R13: ffff88007ce6d060 R14: ffffffff81a46d80 R15: ffff88007c6e8018 FS: 00007f13dbf6f840(0000) GS:ffffffff81a23000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 000000007b7e5000 CR4: 00000000000006b0 Stack: ffffffff810b380d 0000000000000002 ffff88007f865e18 ffffffff81167069 ffff88007f865ed8 ffffffff8116a3f5 ffff880037454400 ffff88007c6e8018 ffff88007c6e8028 ffff88007c6e8328 ffff88007c6e8000 ffff88007ce6d000 Call Trace: [<ffffffff810b380d>] ? cgroup_mkdir+0x3bd/0x740 [<ffffffff81167069>] ? lookup_hash+0x19/0x20 [<ffffffff8116a3f5>] ? kern_path_create+0x95/0x170 [<ffffffff8116ce3e>] vfs_mkdir+0x9e/0xf0 [<ffffffff8116d7a0>] SyS_mkdirat+0x60/0xe0 [<ffffffff8116d839>] SyS_mkdir+0x19/0x20 [<ffffffff814c960d>] tracesys+0xcf/0xd4 Code: ad 70 ff ff ff 48 89 9d 60 ff ff ff 4d 89 d5 4c 8b bd 68 ff ff ff 4c 8b 65 88 eb 50 0f 1f 00 48 8b 43 18 a8 03 0f 85 6c 03 00 00 <ff> 00 e8 1d 0a fb ff 85 c0 74 0d 80 3d f0 45 a1 00 00 0f 84 4c RIP [<ffffffff810b37cc>] cgroup_mkdir+0x37c/0x740 RSP <ffff88007f865df8> CR2: 0000000000000000 ---[ end trace a4b14b49bc46fd60 ]--- Signed-off-by: Li Zhong <zhong@linux.vnet.ibm.com> Acked-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-14Merge branch 'akpm' (patches from Andrew Morton)Linus Torvalds1-0/+6
Merge a bunch of fixes from Andrew Morton. * emailed patches from Andrew Morton <akpm@linux-foundation.org>: fs/proc/task_mmu.c: fix buffer overflow in add_page_map() arch: *: Kconfig: add "kernel/Kconfig.freezer" to "arch/*/Kconfig" ocfs2: fix null pointer dereference in ocfs2_dir_foreach_blk_id() x86 get_unmapped_area(): use proper mmap base for bottom-up direction ocfs2: fix NULL pointer dereference in ocfs2_duplicate_clusters_by_page ocfs2: Revert 40bd62e to avoid regression in extended allocation drivers/rtc/rtc-stmp3xxx.c: provide timeout for potentially endless loop polling a HW bit hugetlb: fix lockdep splat caused by pmd sharing aoe: adjust ref of head for compound page tails microblaze: fix clone syscall mm: save soft-dirty bits on file pages mm: save soft-dirty bits on swapped pages memcg: don't initialize kmem-cache destroying work for root caches
2013-08-13microblaze: fix clone syscallMichal Simek1-0/+6
Fix inadvertent breakage in the clone syscall ABI for Microblaze that was introduced in commit f3268edbe6fe ("microblaze: switch to generic fork/vfork/clone"). The Microblaze syscall ABI for clone takes the parent tid address in the 4th argument; the third argument slot is used for the stack size. The incorrectly-used CLONE_BACKWARDS type assigned parent tid to the 3rd slot. This commit restores the original ABI so that existing userspace libc code will work correctly. All kernel versions from v3.8-rc1 were affected. Signed-off-by: Michal Simek <michal.simek@xilinx.com> Cc: <stable@vger.kernel.org> Signed-off-by: Andrew Morton <akpm@linux-foundation.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-13cpuset: remove an unncessary forward declarationLi Zefan1-3/+0
Signed-off-by: Li Zefan <lizefan@huawei.com> Signed-off-by: Tejun Heo <tj@kernel.org>
2013-08-13cgroup: RCU protect each cgroup_subsys_state releaseTejun Heo1-16/+37
With the planned unified hierarchy, individual css's will be created and destroyed dynamically across the lifetime of a cgroup. To enable such usages, css destruction is being decoupled from cgroup destruction. Most of the destruction path has been decoupled but the actual free of css still depends on cgroup free path. When all css refs are drained, css_release() kicks off css_free_work_fn() which puts the cgroup. When the cgroup refcnt reaches zero, cgroup_diput() is invoked which in turn schedules RCU free of the cgroup. After a grace period, all css's are freed along with the cgroup itself. This patch moves the RCU grace period and css freeing from cgroup release path to css release path. css_release(), instead of kicking off css_free_work_fn() directly, schedules RCU callback css_free_rcu_fn() which in turn kicks off css_free_work_fn() after a RCU grace period. css_free_work_fn() is updated to free the css directly. The five-way punting - percpu ref kill confirmation, a work item, percpu ref release, RCU grace period, and again a work item - is quite hairy but the work items are there only to provide process context and the actual sequence is kill confirm -> release -> RCU free, which isn't simple but not too crazy. This removes cgroup_css() usage after offline_css() allowing clearing cgroup->subsys[] from offline_css(), which makes it consistent with online_css() and brings it closer to proper lifetime management for individual css's. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: move subsys file removal to kill_css()Tejun Heo1-7/+9
With the planned unified hierarchy, individual css's will be created and destroyed dynamically across the lifetime of a cgroup. To enable such usages, css destruction is being decoupled from cgroup destruction. This patch moves subsys file removal from cgroup_destroy_locked() to kill_css(). While this changes the order of destruction operations, the changes shouldn't be noticeable to cgroup subsystems or userland. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: factor out kill_css()Tejun Heo1-23/+35
Factor out css ref killing from cgroup_destroy_locked() into kill_css(). We're gonna add more to the path and the factored out function will eventually be called from other places too. While at it, replace open coded percpu_ref_get() with css_get() for consistency. This shouldn't cause any functional difference as the function is not used for root cgroups. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: decouple cgroup_subsys_state destruction from cgroup destructionTejun Heo1-28/+24
Currently, css (cgroup_subsys_state) lifetime is tied to that of the associated cgroup. css's are created when the associated cgroup is created and destroyed when it gets destroyed. Also, individual css's aren't RCU protected but the whole cgroup is. With the planned unified hierarchy, css's will need to be dynamically created and destroyed within the lifetime of a cgroup. To enable such usages, this patch decouples css destruction from cgroup destruction - offline_css() invocation and the final css_put() are moved from cgroup_destroy_css_killed() to css_killed_work_fn(). Now each css is individually offlined and put as its reference count is killed instead of waiting for all css's attached to the cgroup to finish refcnt killing and then proceeding to offlining and putting them together. While this changes the order of destruction operations, the changes shouldn't be noticeable to cgroup subsystems or userland. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: replace cgroup->css_kill_cnt with ->nr_cssTejun Heo1-24/+28
Currently, css (cgroup_subsys_state) lifetime is tied to that of the associated cgroup. With the planned unified hierarchy, css's will be dynamically created and destroyed within the lifetime of a cgroup. To enable such usages, css's will be individually RCU protected instead of being tied to the cgroup. cgroup->css_kill_cnt is used during cgroup destruction to wait for css reference count disable; however, this model doesn't work once css's lifetimes are managed separately from cgroup's. This patch replaces it with cgroup->nr_css which is an cgroup_mutex protected integer counting the number of attached css's. The count is incremented from online_css() and decremented after refcnt kill is confirmed. If the count reaches zero and the cgroup is marked dead, the second stage of cgroup destruction is kicked off. If a cgroup doesn't have any css attached at the time of rmdir, cgroup_destroy_locked() now invokes the second stage directly as no css kill confirmation would happen. cgroup_offline_fn() - the second step of cgroup destruction - is renamed to cgroup_destroy_css_killed() and now expects to be called with cgroup_mutex held. While this patch changes how css destruction is punted to work items, it shouldn't change any visible behavior. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: bounce cgroup_subsys_state ref kill confirmation to a work itemTejun Heo1-3/+18
css (cgroup_subsys_state) offlining, which requires process context, will be moved to ref kill confirmation. In preparation, bounce css_killed handling through css->destroy_work. css_ref_killed_fn() is renamed to css_killed_ref_fn() so that it's consistent with the new css_killed_work_fn(). This patch adds an additional work item bouncing but doesn't change the actual logic. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: move cgroup->subsys[] assignment to online_css()Tejun Heo1-10/+11
Currently, css (cgroup_subsys_state) lifetime is tied to that of the associated cgroup. With the planned unified hierarchy, css's will be dynamically created and destroyed within the lifetime of a cgroup. To enable such usages, css's will be individually RCU protected instead of being tied to the cgroup. In preparation, this patch moves cgroup->subsys[] assignment from init_css() to online_css(). As this means that a newly initialized css should be remembered separately and that cgroup_css() returns NULL between init and online, cgroup_create() is updated so that it stores newly created css's in a local array css_ar[] and cgroup_init/load_subsys() are updated to use local variable @css instead of using cgroup_css(). This change also slightly simplifies error path of cgroup_create(). While this patch changes when cgroup->subsys[] is initialized, this change isn't visible to subsystems or userland. v2: This patch wasn't updated accordingly after the previous "cgroup: reorganize css init / exit paths" was updated leading to missing a css_ar[] conversion in cgroup_create() and thus boot failure. Fix it. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13Merge branch 'sched-urgent-for-linus' of ↵Linus Torvalds3-25/+71
git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip Pull scheduler fixes from Ingo Molnar: "Docbook fixes that make 99% of the diffstat, plus a oneliner fix" * 'sched-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: sched: Ensure update_cfs_shares() is called for parents of continuously-running tasks sched: Fix some kernel-doc warnings
2013-08-14PM / QoS: Fix workqueue deadlock when using pm_qos_update_request_timeout()Stephen Boyd1-7/+13
pm_qos_update_request_timeout() updates a qos and then schedules a delayed work item to bring the qos back down to the default after the timeout. When the work item runs, pm_qos_work_fn() will call pm_qos_update_request() and deadlock because it tries to cancel itself via cancel_delayed_work_sync(). Future callers of that qos will also hang waiting to cancel the work that is canceling itself. Let's extract the little bit of code that does the real work of pm_qos_update_request() and call it from the work function so that we don't deadlock. Before ed1ac6e (PM: don't use [delayed_]work_pending()) this didn't happen because the work function wouldn't try to cancel itself. Signed-off-by: Stephen Boyd <sboyd@codeaurora.org> Reviewed-by: Tejun Heo <tj@kernel.org> Cc: 3.9+ <stable@vger.kernel.org> # 3.9+ Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
2013-08-13sched: fix the theoretical signal_wake_up() vs schedule() raceOleg Nesterov1-1/+13
This is only theoretical, but after try_to_wake_up(p) was changed to check p->state under p->pi_lock the code like __set_current_state(TASK_INTERRUPTIBLE); schedule(); can miss a signal. This is the special case of wait-for-condition, it relies on try_to_wake_up/schedule interaction and thus it does not need mb() between __set_current_state() and if(signal_pending). However, this __set_current_state() can move into the critical section protected by rq->lock, now that try_to_wake_up() takes another lock we need to ensure that it can't be reordered with "if (signal_pending(current))" check inside that section. The patch is actually one-liner, it simply adds smp_wmb() before spin_lock_irq(rq->lock). This is what try_to_wake_up() already does by the same reason. We turn this wmb() into the new helper, smp_mb__before_spinlock(), for better documentation and to allow the architectures to change the default implementation. While at it, kill smp_mb__after_lock(), it has no callers. Perhaps we can also add smp_mb__before/after_spinunlock() for prepare_to_wait(). Signed-off-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Peter Zijlstra <peterz@infradead.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2013-08-13cgroup: reorganize css init / exit pathsTejun Heo1-27/+23
css (cgroup_subsys_state) lifetime management is about to be restructured. In prepartion, make the following mostly trivial changes. * init_cgroup_css() is renamed to init_css() so that it's consistent with other css handling functions. * alloc_css_id(), online_css() and offline_css() updated to take @css instead of cgroups and subsys IDs. This patch doesn't make any functional changes. v2: v1 merged two for_each_root_subsys() loops in cgroup_create() but Li Zefan pointed out that it breaks error path. Dropped. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: add __rcu modifier to cgroup->subsys[]Tejun Heo1-5/+14
For the planned unified hierarchy, each css (cgroup_subsys_state) will be RCU protected so that it can be created and destroyed individually while allowing RCU accesses. Previous changes ensured that all cgroup->subsys[] accesses use the cgroup_css() accessor. This patch adds __rcu modifier to cgroup->subsys[], add matching RCU dereference in cgroup_css() and convert all assignments to either rcu_assign_pointer() or RCU_INIT_POINTER(). This change prepares for the actual RCUfication of css's and doesn't introduce any visible behavior change. The conversion is verified with sparse and all accesses are properly RCU annotated. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: make cgroup_file_open() rcu_read_lock() around cgroup_css() and add ↵Tejun Heo1-17/+31
cfent->css For the planned unified hierarchy, each css (cgroup_subsys_state) will be RCU protected so that it can be created and destroyed individually while allowing RCU accesses, and cgroup_css() will soon require either holding cgroup_mutex or RCU read lock. This patch updates cgroup_file_open() such that it acquires the associated css under rcu_read_lock(). While cgroup_file_css() usages in other file operations are safe due to the reference from open, cgroup_css() wouldn't know that and will still trigger warnings. It'd be cleanest to store the acquired css in file->prvidate_data for further file operations but that's already used by seqfile. This patch instead adds cfent->css to cache the associated css. Note that while this field is initialized during cfe init, it should only be considered valid while the file is open. This patch doesn't change visible behavior. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>
2013-08-13cgroup: cgroup_css_from_dir() now should be called with RCU read lockedTejun Heo2-2/+13
cgroup->subsys[] will become RCU protected and thus all cgroup_css() usages should either be under RCU read lock or cgroup_mutex. This patch updates cgroup_css_from_dir() which returns the matching cgroup_subsys_state given a directory file and subsys_id so that it requires RCU read lock and updates its sole user perf_cgroup_connect(). Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com> Cc: Steven Rostedt <rostedt@goodmis.org> Cc: Frederic Weisbecker <fweisbec@gmail.com> Cc: Ingo Molnar <mingo@redhat.com>
2013-08-13cgroup: add cgroup_subsys_state->parentTejun Heo1-3/+15
With the planned unified hierarchy, css's (cgroup_subsys_state) will be RCU protected and allowed to be attached and detached dynamically over the course of a cgroup's lifetime. This means that css's will stay accessible after being detached from its cgroup - the matching pointer in cgroup->subsys[] cleared - for ref draining and RCU grace period. cgroup core still wants to guarantee that the parent css is never destroyed before its children and css_parent() always returns the parent regardless of the state of the child css as long as it's accessible. This patch makes css's hold onto their parents and adds css->parent so that the parent css is never detroyed before its children and can be determined without consulting the cgroups. cgroup->dummy_css is also updated to point to the parent dummy_css; however, it doesn't need to worry about object lifetime as the parent cgroup is already pinned by the child. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Li Zefan <lizefan@huawei.com>