summaryrefslogtreecommitdiffstats
path: root/kernel
Commit message (Collapse)AuthorAgeFilesLines
* threadgroup: extend threadgroup_lock() to cover exit and execTejun Heo2011-12-121-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | threadgroup_lock() protected only protected against new addition to the threadgroup, which was inherently somewhat incomplete and problematic for its only user cgroup. On-going migration could race against exec and exit leading to interesting problems - the symmetry between various attach methods, task exiting during method execution, ->exit() racing against attach methods, migrating task switching basic properties during exec and so on. This patch extends threadgroup_lock() such that it protects against all three threadgroup altering operations - fork, exit and exec. For exit, threadgroup_change_begin/end() calls are added to exit_signals around assertion of PF_EXITING. For exec, threadgroup_[un]lock() are updated to also grab and release cred_guard_mutex. With this change, threadgroup_lock() guarantees that the target threadgroup will remain stable - no new task will be added, no new PF_EXITING will be set and exec won't happen. The next patch will update cgroup so that it can take full advantage of this change. -v2: beefed up comment as suggested by Frederic. -v3: narrowed scope of protection in exit path as suggested by Frederic. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Acked-by: Frederic Weisbecker <fweisbec@gmail.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul Menage <paul@paulmenage.org> Cc: Linus Torvalds <torvalds@linux-foundation.org>
* threadgroup: rename signal->threadgroup_fork_lock to ->group_rwsemTejun Heo2011-12-122-11/+10
| | | | | | | | | | | | | | | | | | | | | | | Make the following renames to prepare for extension of threadgroup locking. * s/signal->threadgroup_fork_lock/signal->group_rwsem/ * s/threadgroup_fork_read_lock()/threadgroup_change_begin()/ * s/threadgroup_fork_read_unlock()/threadgroup_change_end()/ * s/threadgroup_fork_write_lock()/threadgroup_lock()/ * s/threadgroup_fork_write_unlock()/threadgroup_unlock()/ This patch doesn't cause any behavior change. -v2: Rename threadgroup_change_done() to threadgroup_change_end() per KAMEZAWA's suggestion. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Paul Menage <paul@paulmenage.org>
* cgroup: add cgroup_root_mutexTejun Heo2011-12-121-22/+42
| | | | | | | | | | | | | | | | | | | cgroup wants to make threadgroup stable while modifying cgroup hierarchies which will introduce locking dependency on cred_guard_mutex from cgroup_mutex. This unfortunately completes circular dependency. A. cgroup_mutex -> cred_guard_mutex -> s_type->i_mutex_key -> namespace_sem B. namespace_sem -> cgroup_mutex B is from cgroup_show_options() and this patch breaks it by introducing another mutex cgroup_root_mutex which nests inside cgroup_mutex and protects cgroupfs_root. Signed-off-by: Tejun Heo <tj@kernel.org> Reviewed-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com> Acked-by: Li Zefan <lizf@cn.fujitsu.com> Cc: Oleg Nesterov <oleg@redhat.com>
* Merge branch 'pm-freezer' of ↵Rafael J. Wysocki2011-11-239-205/+196
|\ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc into pm-freezer * 'pm-freezer' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/misc: (24 commits) freezer: fix wait_event_freezable/__thaw_task races freezer: kill unused set_freezable_with_signal() dmatest: don't use set_freezable_with_signal() usb_storage: don't use set_freezable_with_signal() freezer: remove unused @sig_only from freeze_task() freezer: use lock_task_sighand() in fake_signal_wake_up() freezer: restructure __refrigerator() freezer: fix set_freezable[_with_signal]() race freezer: remove should_send_signal() and update frozen() freezer: remove now unused TIF_FREEZE freezer: make freezing() test freeze conditions in effect instead of TIF_FREEZE cgroup_freezer: prepare for removal of TIF_FREEZE freezer: clean up freeze_processes() failure path freezer: kill PF_FREEZING freezer: test freezable conditions while holding freezer_lock freezer: make freezing indicate freeze condition in effect freezer: use dedicated lock instead of task_lock() + memory barrier freezer: don't distinguish nosig tasks on thaw freezer: remove racy clear_freeze_flag() and set PF_NOFREEZE on dead tasks freezer: rename thaw_process() to __thaw_task() and simplify the implementation ...
| * freezer: kill unused set_freezable_with_signal()Tejun Heo2011-11-232-22/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There's no in-kernel user of set_freezable_with_signal() left. Mixing TIF_SIGPENDING with kernel threads can lead to nasty corner cases as kernel threads never travel signal delivery path on their own. e.g. the current implementation is buggy in the cancelation path of __thaw_task(). It calls recalc_sigpending_and_wake() in an attempt to clear TIF_SIGPENDING but the function never clears it regardless of sigpending state. This means that signallable freezable kthreads may continue executing with !freezing() && stuck TIF_SIGPENDING, which can be troublesome. This patch removes set_freezable_with_signal() along with PF_FREEZER_NOSIG and recalc_sigpending*() calls in freezer. User tasks get TIF_SIGPENDING, kernel tasks get woken up and the spurious sigpending is dealt with in the usual signal delivery path. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com>
| * freezer: remove unused @sig_only from freeze_task()Tejun Heo2011-11-213-18/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After "freezer: make freezing() test freeze conditions in effect instead of TIF_FREEZE", freezing() returns authoritative answer on whether the current task should freeze or not and freeze_task() doesn't need or use @sig_only. Remove it. While at it, rewrite function comment for freeze_task() and rename @sig_only to @user_only in try_to_freeze_tasks(). This patch doesn't cause any functional change. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Oleg Nesterov <oleg@redhat.com>
| * freezer: use lock_task_sighand() in fake_signal_wake_up()Tejun Heo2011-11-211-3/+4
| | | | | | | | | | | | | | | | | | | | | | | | | | cgroup_freezer calls freeze_task() without holding tasklist_lock and, if the task is exiting, its ->sighand may be gone by the time fake_signal_wake_up() is called. Use lock_task_sighand() instead of accessing ->sighand directly. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl> Cc: Paul Menage <paul@paulmenage.org>
| * freezer: restructure __refrigerator()Tejun Heo2011-11-211-21/+11
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If another freeze happens before all tasks leave FROZEN state after being thawed, the freezer can see the existing FROZEN and consider the tasks to be frozen but they can clear FROZEN without checking the new freezing(). Oleg suggested restructuring __refrigerator() such that there's single condition check section inside freezer_lock and sigpending is cleared afterwards, which fixes the problem and simplifies the code. Restructure accordingly. -v2: Frozen loop exited without releasing freezer_lock. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Reported-by: Oleg Nesterov <oleg@redhat.com> Acked-by: Oleg Nesterov <oleg@redhat.com> Cc: "Rafael J. Wysocki" <rjw@sisk.pl>
| * freezer: fix set_freezable[_with_signal]() raceTejun Heo2011-11-211-0/+25
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | A kthread doing set_freezable*() may race with on-going PM freeze and the freezer might think all tasks are frozen while the new freezable kthread is merrily proceeding to execute code paths which aren't supposed to be executing during PM freeze. Reimplement set_freezable[_with_signal]() using __set_freezable() such that freezable PF flags are modified under freezer_lock and try_to_freeze() is called afterwards. This eliminates race condition against freezing. Note: Separated out from larger patch to resolve fix order dependency Oleg pointed out. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com>
| * freezer: remove should_send_signal() and update frozen()Tejun Heo2011-11-211-1/+1
| | | | | | | | | | | | | | | | | | should_send_signal() is only used in freezer.c. Exporting them only increases chance of abuse. Open code the two users and remove it. Update frozen() to return bool. Signed-off-by: Tejun Heo <tj@kernel.org>
| * freezer: make freezing() test freeze conditions in effect instead of TIF_FREEZETejun Heo2011-11-214-28/+60
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Using TIF_FREEZE for freezing worked when there was only single freezing condition (the PM one); however, now there is also the cgroup_freezer and single bit flag is getting clumsy. thaw_processes() is already testing whether cgroup freezing in in effect to avoid thawing tasks which were frozen by both PM and cgroup freezers. This is racy (nothing prevents race against cgroup freezing) and fragile. A much simpler way is to test actual freeze conditions from freezing() - ie. directly test whether PM or cgroup freezing is in effect. This patch adds variables to indicate whether and what type of freezing conditions are in effect and reimplements freezing() such that it directly tests whether any of the two freezing conditions is active and the task should freeze. On fast path, freezing() is still very cheap - it only tests system_freezing_cnt. This makes the clumsy dancing aroung TIF_FREEZE unnecessary and freeze/thaw operations more usual - updating state variables for the new state and nudging target tasks so that they notice the new state and comply. As long as the nudging happens after state update, it's race-free. * This allows use of freezing() in freeze_task(). Replace the open coded tests with freezing(). * p != current test is added to warning printing conditions in try_to_freeze_tasks() failure path. This is necessary as freezing() is now true for the task which initiated freezing too. -v2: Oleg pointed out that re-freezing FROZEN cgroup could increment system_freezing_cnt. Fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Paul Menage <paul@paulmenage.org> (for the cgroup portions)
| * cgroup_freezer: prepare for removal of TIF_FREEZETejun Heo2011-11-212-28/+14
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | TIF_FREEZE will be removed soon and freezing() will directly test whether any freezing condition is in effect. Make the following changes in preparation. * Rename cgroup_freezing_or_frozen() to cgroup_freezing() and make it return bool. * Make cgroup_freezing() access task_freezer() under rcu read lock instead of task_lock(). This makes the state dereferencing racy against task moving to another cgroup; however, it was already racy without this change as ->state dereference wasn't synchronized. This will be later dealt with using attach hooks. * freezer->state is now set before trying to push tasks into the target state. -v2: Oleg pointed out that freeze_change_state() was setting freeze->state incorrectly to CGROUP_FROZEN instead of CGROUP_FREEZING. Fixed. -v3: Matt pointed out that setting CGROUP_FROZEN used to always invoke try_to_freeze_cgroup() regardless of the current state. Patch updated such that the actual freeze/thaw operations are always performed on invocation. This shouldn't make any difference unless something is broken. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Paul Menage <paul@paulmenage.org> Cc: Li Zefan <lizf@cn.fujitsu.com> Cc: Oleg Nesterov <oleg@redhat.com>
| * freezer: clean up freeze_processes() failure pathTejun Heo2011-11-215-45/+23
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | freeze_processes() failure path is rather messy. Freezing is canceled for workqueues and tasks which aren't frozen yet but frozen tasks are left alone and should be thawed by the caller and of course some callers (xen and kexec) didn't do it. This patch updates __thaw_task() to handle cancelation correctly and makes freeze_processes() and freeze_kernel_threads() call thaw_processes() on failure instead so that the system is fully thawed on failure. Unnecessary [suspend_]thaw_processes() calls are removed from kernel/power/hibernate.c, suspend.c and user.c. While at it, restructure error checking if clause in suspend_prepare() to be less weird. -v2: Srivatsa spotted missing removal of suspend_thaw_processes() in suspend_prepare() and error in commit message. Updated. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
| * freezer: kill PF_FREEZINGTejun Heo2011-11-211-6/+0
| | | | | | | | | | | | | | | | With the previous changes, there's no meaningful difference between PF_FREEZING and PF_FROZEN. Remove PF_FREEZING and use PF_FROZEN instead in task_contributes_to_load(). Signed-off-by: Tejun Heo <tj@kernel.org>
| * freezer: test freezable conditions while holding freezer_lockTejun Heo2011-11-212-16/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | try_to_freeze_tasks() and thaw_processes() use freezable() and frozen() as preliminary tests before initiating operations on a task. These are done without any synchronization and hinder with synchronization cleanup without any real performance benefits. In try_to_freeze_tasks(), open code self test and move PF_NOFREEZE and frozen() tests inside freezer_lock in freeze_task(). thaw_processes() can simply drop freezable() test as frozen() test in __thaw_task() is enough. Note: This used to be a part of larger patch to fix set_freezable() race. Separated out to satisfy ordering among dependent fixes. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com>
| * freezer: make freezing indicate freeze condition in effectTejun Heo2011-11-213-20/+27
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Currently freezing (TIF_FREEZE) and frozen (PF_FROZEN) states are interlocked - freezing is set to request freeze and when the task actually freezes, it clears freezing and sets frozen. This interlocking makes things more complex than necessary - freezing doesn't mean there's freezing condition in effect and frozen doesn't match the task actually entering and leaving frozen state (it's cleared by the thawing task). This patch makes freezing indicate that freeze condition is in effect. A task enters and stays frozen if freezing. This makes PF_FROZEN manipulation done only by the task itself and prevents wakeup from __thaw_task() leaking outside of refrigerator. The only place which needs to tell freezing && !frozen is try_to_freeze_task() to whine about tasks which don't enter frozen. It's updated to test the condition explicitly. With the change, frozen() state my linger after __thaw_task() until the task wakes up and exits fridge. This can trigger BUG_ON() in update_if_frozen(). Work it around by testing freezing() && frozen() instead of frozen(). -v2: Oleg pointed out missing re-check of freezing() when trying to clear FROZEN and possible spurious BUG_ON() trigger in update_if_frozen(). Both fixed. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com> Cc: Paul Menage <paul@paulmenage.org>
| * freezer: use dedicated lock instead of task_lock() + memory barrierTejun Heo2011-11-212-49/+37
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Freezer synchronization is needlessly complicated - it's by no means a hot path and the priority is staying unintrusive and safe. This patch makes it simply use a dedicated lock instead of piggy-backing on task_lock() and playing with memory barriers. On the failure path of try_to_freeze_tasks(), locking is moved from it to cancel_freezing(). This makes the frozen() test racy but the race here is a non-issue as the warning is printed for tasks which failed to enter frozen for 20 seconds and race on PF_FROZEN at the last moment doesn't change anything. This simplifies freezer implementation and eases further changes including some race fixes. Signed-off-by: Tejun Heo <tj@kernel.org>
| * freezer: don't distinguish nosig tasks on thawTejun Heo2011-11-211-13/+7
| | | | | | | | | | | | | | | | | | | | There's no point in thawing nosig tasks before others. There's no ordering requirement between the two groups on thaw, which the staged thawing can't guarantee anyway. Simplify thaw_processes() by removing the distinction and collapsing thaw_tasks() into thaw_processes(). This will help further updates to freezer. Signed-off-by: Tejun Heo <tj@kernel.org>
| * freezer: remove racy clear_freeze_flag() and set PF_NOFREEZE on dead tasksTejun Heo2011-11-212-4/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | clear_freeze_flag() in exit_mm() is racy. Freezing can start afterwards. Remove it. Skipping freezer for exiting task will be properly implemented later. Also, freezable() was testing exit_state directly to make system freezer ignore dead tasks. Let the exiting task set PF_NOFREEZE after entering TASK_DEAD instead. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Oleg Nesterov <oleg@redhat.com>
| * freezer: rename thaw_process() to __thaw_task() and simplify the implementationTejun Heo2011-11-213-24/+16
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | thaw_process() now has only internal users - system and cgroup freezers. Remove the unnecessary return value, rename, unexport and collapse __thaw_process() into it. This will help further updates to the freezer code. -v3: oom_kill grew a use of thaw_process() while this patch was pending. Convert it to use __thaw_task() for now. In the longer term, this should be handled by allowing tasks to die if killed even if it's frozen. -v2: minor style update as suggested by Matt. Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Paul Menage <menage@google.com> Cc: Matt Helsley <matthltc@us.ibm.com>
| * freezer: implement and use kthread_freezable_should_stop()Tejun Heo2011-11-212-2/+29
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Writeback and thinkpad_acpi have been using thaw_process() to prevent deadlock between the freezer and kthread_stop(); unfortunately, this is inherently racy - nothing prevents freezing from happening between thaw_process() and kthread_stop(). This patch implements kthread_freezable_should_stop() which enters refrigerator if necessary but is guaranteed to return if kthread_stop() is invoked. Both thaw_process() users are converted to use the new function. Note that this deadlock condition exists for many of freezable kthreads. They need to be converted to use the new should_stop or freezable workqueue. Tested with synthetic test case. Signed-off-by: Tejun Heo <tj@kernel.org> Acked-by: Henrique de Moraes Holschuh <ibm-acpi@hmh.eng.br> Cc: Jens Axboe <axboe@kernel.dk> Cc: Oleg Nesterov <oleg@redhat.com>
| * freezer: unexport refrigerator() and update try_to_freeze() slightlyTejun Heo2011-11-211-3/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | There is no reason to export two functions for entering the refrigerator. Calling refrigerator() instead of try_to_freeze() doesn't save anything noticeable or removes any race condition. * Rename refrigerator() to __refrigerator() and make it return bool indicating whether it scheduled out for freezing. * Update try_to_freeze() to return bool and relay the return value of __refrigerator() if freezing(). * Convert all refrigerator() users to try_to_freeze(). * Update documentation accordingly. * While at it, add might_sleep() to try_to_freeze(). Signed-off-by: Tejun Heo <tj@kernel.org> Cc: Samuel Ortiz <samuel@sortiz.org> Cc: Chris Mason <chris.mason@oracle.com> Cc: "Theodore Ts'o" <tytso@mit.edu> Cc: Steven Whitehouse <swhiteho@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Jan Kara <jack@suse.cz> Cc: KONISHI Ryusuke <konishi.ryusuke@lab.ntt.co.jp> Cc: Christoph Hellwig <hch@infradead.org>
| * freezer: fix current->state restoration race in refrigerator()Tejun Heo2011-11-211-1/+7
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | refrigerator() saves current->state before entering frozen state and restores it before returning using __set_current_state(); however, this is racy, for example, please consider the following sequence. set_current_state(TASK_INTERRUPTIBLE); try_to_freeze(); if (kthread_should_stop()) break; schedule(); If kthread_stop() races with ->state restoration, the restoration can restore ->state to TASK_INTERRUPTIBLE after kthread_stop() sets it to TASK_RUNNING but kthread_should_stop() may still see zero ->should_stop because there's no memory barrier between restoring TASK_INTERRUPTIBLE and kthread_should_stop() test. This isn't restricted to kthread_should_stop(). current->state is often used in memory barrier based synchronization and silently restoring it w/o mb breaks them. Use set_current_state() instead. Signed-off-by: Tejun Heo <tj@kernel.org>
* | PM / Hibernate: Do not leak memory in error/test code pathsRafael J. Wysocki2011-11-231-6/+10
| | | | | | | | | | | | | | | | | | | | | | | | The hibernation core code forgets to release memory preallocated for hibernation if there's an error in its early stages or if test modes causing hibernation_snapshot() to return early are used. This causes the system to be hardly usable, because the amount of preallocated memory is usually huge. Fix this problem. Reported-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl> Acked-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com>
* | Merge branch 'writeback-for-linus' of ↵Linus Torvalds2011-11-221-5/+0
|\ \ | |/ |/| | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux * 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: remove vm_dirties and task->dirties writeback: hard throttle 1000+ dd on a slow USB stick mm: Make task in balance_dirty_pages() killable
| * writeback: remove vm_dirties and task->dirtiesWu Fengguang2011-11-171-5/+0
| | | | | | | | | | | | They are not used any more. Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
* | Merge branch 'pm-fixes' of ↵Linus Torvalds2011-11-202-7/+19
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm * 'pm-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/rafael/linux-pm: PM / Suspend: Fix bug in suspend statistics update PM / Hibernate: Fix the early termination of test modes PM / shmobile: Fix build of sh7372_pm_init() for CONFIG_PM unset PM Sleep: Do not extend wakeup paths to devices with ignore_children set PM / driver core: disable device's runtime PM during shutdown PM / devfreq: correct Kconfig dependency PM / devfreq: fix use after free in devfreq_remove_device PM / shmobile: Avoid restoring the INTCS state during initialization PM / devfreq: Remove compiler error after irq.h update PM / QoS: Properly use the WARN() macro in dev_pm_qos_add_request() PM / Clocks: Only disable enabled clocks in pm_clk_suspend() ARM: mach-shmobile: sh7372 A3SP no_suspend_console fix PM / shmobile: Don't skip debugging output in pd_power_up()
| * | PM / Suspend: Fix bug in suspend statistics updateSrivatsa S. Bhat2011-11-191-1/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | After commit 2a77c46de1e3dace73745015635ebbc648eca69c (PM / Suspend: Add statistics debugfs file for suspend to RAM) a missing pair of braces inside the state_store() function causes even invalid arguments to suspend to be wrongly treated as failed suspend attempts. Fix this. [rjw: Put the hash/subject of the buggy commit into the changelog.] Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
| * | PM / Hibernate: Fix the early termination of test modesSrivatsa S. Bhat2011-11-181-6/+17
| |/ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Commit 2aede851ddf08666f68ffc17be446420e9d2a056 (PM / Hibernate: Freeze kernel threads after preallocating memory) postponed the freezing of kernel threads to after preallocating memory for hibernation. But while doing that, the hibernation test TEST_FREEZER and the test mode HIBERNATION_TESTPROC were not moved accordingly. As a result, when using these test modes, it only goes upto the freezing of userspace and exits, when in fact it should go till the complete end of task freezing stage, namely the freezing of kernel threads as well. So, move these points of exit to appropriate places so that freezing of kernel threads is also tested while using these test harnesses. Signed-off-by: Srivatsa S. Bhat <srivatsa.bhat@linux.vnet.ibm.com> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* | Merge branch 'irq-urgent-for-linus' of ↵Linus Torvalds2011-11-171-1/+1
|\ \ | |/ |/| | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip * 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: genirq: Fix irqfixup, irqpoll regression
| * genirq: Fix irqfixup, irqpoll regressionEdward Donovan2011-11-031-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | commit d05c65fff0 ("genirq: spurious: Run only one poller at a time") introduced a regression, leaving the boot options 'irqfixup' and 'irqpoll' non-functional. The patch placed tests in each function, to exit if the function is already running. The test in 'misrouted_irq' exited when it should have proceeded, effectively disabling 'misrouted_irq' and 'poll_spurious_irqs'. The check for an already running poller needs to be "!= 1" not "== 1" as "1" is the value when the first poller starts running. Signed-off-by: Edward Donovan <edward.donovan@numble.net> Cc: maciej.rutecki@gmail.com Link: http://lkml.kernel.org/r/1320175784-6745-1-git-send-email-edward.donovan@numble.net Cc: stable@vger.kernel.org # >= 2.6.39 Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
* | PM / QoS: Set cpu_dma_pm_qos->nameDominik Brodowski2011-11-071-0/+1
| | | | | | | | | | | | | | | | | | | | | | Since commit 4a31a334, the name of this misc device is not initialized, which leads to a funny device named /dev/(null) being created and /proc/misc containing an entry with just a number but no name. The latter leads to complaints by cryptsetup, which caused me to investigate this matter. Signed-off-by: Dominik Brodowski <linux@dominikbrodowski.net> Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
* | Merge branch 'upstream/jump-label-noearly' of ↵Linus Torvalds2011-11-061-16/+21
|\ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen * 'upstream/jump-label-noearly' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen: jump-label: initialize jump-label subsystem much earlier x86/jump_label: add arch_jump_label_transform_static() s390/jump-label: add arch_jump_label_transform_static() jump_label: add arch_jump_label_transform_static() to optimise non-live code updates sparc/jump_label: drop arch_jump_label_text_poke_early() x86/jump_label: drop arch_jump_label_text_poke_early() jump_label: if a key has already been initialized, don't nop it out stop_machine: make stop_machine safe and efficient to call early jump_label: use proper atomic_t initializer Conflicts: - arch/x86/kernel/jump_label.c Added __init_or_module to arch_jump_label_text_poke_early vs removal of that function entirely - kernel/stop_machine.c same patch ("stop_machine: make stop_machine safe and efficient to call early") merged twice, with whitespace fix in one version
| * | jump-label: initialize jump-label subsystem much earlierJeremy Fitzhardinge2011-10-251-4/+1
| | | | | | | | | | | | | | | | | | | | | | | | Initialize jump_labels much, much earlier, so they're available for use during system setup. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
| * | jump_label: add arch_jump_label_transform_static() to optimise non-live code ↵Jeremy Fitzhardinge2011-10-251-3/+15
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | updates When updating a newly loaded module, the code is definitely not yet executing on any processor, so it can be updated with no need for any heavyweight synchronization. This patch adds arch_jump_label_static() which is implemented as arch_jump_label_transform() by default, but architectures can override it if it avoids, say, a call to stop_machine(). Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
| * | jump_label: if a key has already been initialized, don't nop it outJeremy Fitzhardinge2011-10-251-12/+8
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | If a key has been enabled before jump_label_init() is called, don't nop it out. This removes arch_jump_label_text_poke_early() (which can only nop out a site) and uses arch_jump_label_transform() instead. Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Jason Baron <jbaron@redhat.com> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
| * | stop_machine: make stop_machine safe and efficient to call earlyJeremy Fitzhardinge2011-10-251-0/+22
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Make stop_machine() safe to call early in boot, before stop_machine() has been set up, by simply calling the callback function directly if there's only one CPU online. [ Fixes from AKPM: - add comment - local_irq_flags, not save_flags - also call hard_irq_disable() for systems which need it Tejun suggested using an explicit flag rather than just looking at the online cpu count. ] Signed-off-by: Jeremy Fitzhardinge <jeremy.fitzhardinge@citrix.com> Acked-by: Tejun Heo <tj@kernel.org> Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Rusty Russell <rusty@rustcorp.com.au> Cc: Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: H. Peter Anvin <hpa@linux.intel.com> Cc: Ingo Molnar <mingo@elte.hu> Cc: Steven Rostedt <rostedt@goodmis.org>
* | | Merge branch 'modsplit-Oct31_2011' of ↵Linus Torvalds2011-11-0678-65/+83
|\ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux * 'modsplit-Oct31_2011' of git://git.kernel.org/pub/scm/linux/kernel/git/paulg/linux: (230 commits) Revert "tracing: Include module.h in define_trace.h" irq: don't put module.h into irq.h for tracking irqgen modules. bluetooth: macroize two small inlines to avoid module.h ip_vs.h: fix implicit use of module_get/module_put from module.h nf_conntrack.h: fix up fallout from implicit moduleparam.h presence include: replace linux/module.h with "struct module" wherever possible include: convert various register fcns to macros to avoid include chaining crypto.h: remove unused crypto_tfm_alg_modname() inline uwb.h: fix implicit use of asm/page.h for PAGE_SIZE pm_runtime.h: explicitly requires notifier.h linux/dmaengine.h: fix implicit use of bitmap.h and asm/page.h miscdevice.h: fix up implicit use of lists and types stop_machine.h: fix implicit use of smp.h for smp_processor_id of: fix implicit use of errno.h in include/linux/of.h of_platform.h: delete needless include <linux/module.h> acpi: remove module.h include from platform/aclinux.h miscdevice.h: delete unnecessary inclusion of module.h device_cgroup.h: delete needless include <linux/module.h> net: sch_generic remove redundant use of <linux/module.h> net: inet_timewait_sock doesnt need <linux/module.h> ... Fix up trivial conflicts (other header files, and removal of the ab3550 mfd driver) in - drivers/media/dvb/frontends/dibx000_common.c - drivers/media/video/{mt9m111.c,ov6650.c} - drivers/mfd/ab3550-core.c - include/linux/dmaengine.h
| * | | irq: don't put module.h into irq.h for tracking irqgen modules.Paul Gortmaker2011-10-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Recent commit "irq: Track the owner of irq descriptor" in commit ID b6873807a7143b7 placed module.h into linux/irq.h but we are trying to limit module.h inclusion to just C files that really need it, due to its size and number of children includes. This targets just reversing that include. Add in the basic "struct module" since that is all we really need to ensure things compile. In theory, b687380 should have added the module.h include to the irqdesc.h header as well, but the implicit module.h everywhere presence masked this from showing up. So give it the "struct module" as well. As for the C files, irqdesc.c is only using THIS_MODULE, so it does not need module.h - give it export.h instead. The C file irq/manage.c is now (as of b687380) using try_module_get and module_put and so it needs module.h (which it already has). Also convert the irq_alloc_descs variants to macros, since all they really do is is call the __irq_alloc_descs primitive. This avoids including export.h and no debug info is lost. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: Fix files explicitly needing EXPORT_SYMBOL infrastructurePaul Gortmaker2011-10-3110-0/+10
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These files were getting <linux/module.h> via an implicit non-obvious path, but we want to crush those out of existence since they cost time during compiles of processing thousands of lines of headers for no reason. Give them the lightweight header that just contains the EXPORT_SYMBOL infrastructure. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: fix up module header handling in rcutiny filesPaul Gortmaker2011-10-312-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The file rcutiny.c does not need moduleparam.h header, as there are no modparams in this file. However rcutiny_plugin.h does define a module_init() and a module_exit() and it uses the various MODULE_ macros, so it really does need module.h included. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: params.c needs module.h not moduleparam.hPaul Gortmaker2011-10-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Through various other implicit include paths, some files were getting the full module.h file, and hence living the illusion that they really only needed moduleparam.h -- but the reality is that once you remove the module.h presence, these show up: kernel/params.c:583: warning: ‘struct module_kobject’ declared inside parameter list Such files really require module.h so simply make it so. As the file module.h grabs moduleparam.h on the fly, all will be well. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: ksysfs.c is implicitly using stat.hPaul Gortmaker2011-10-311-0/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | With the module.h usage cleanup, we'll get this: kernel/ksysfs.c:161: error: ‘S_IRUGO’ undeclared here (not in a function) make[2]: *** [kernel/ksysfs.o] Error 1 Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: fix two implicit header assumptions in irq_work.cPaul Gortmaker2011-10-311-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Up until now, this file was getting percpu.h because nearly every file was implicitly getting module.h (and all its sub-includes). But we want to clean that up, so call out percpu.h explicitly. Otherwise we'll get things like this on an ARM build: kernel/irq_work.c:48: error: expected declaration specifiers or '...' before 'irq_work_list' kernel/irq_work.c:48: warning: type defaults to 'int' in declaration of 'DEFINE_PER_CPU' The same thing was happening for builds on ARM for asm/processor.h kernel/irq_work.c: In function 'irq_work_sync': kernel/irq_work.c:166: error: implicit declaration of function 'cpu_relax' Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: fix several implicit usasges of kmod.hPaul Gortmaker2011-10-313-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These files were implicitly relying on <linux/kmod.h> coming in via module.h, as without it we get things like: kernel/power/suspend.c:100: error: implicit declaration of function ‘usermodehelper_disable’ kernel/power/suspend.c:109: error: implicit declaration of function ‘usermodehelper_enable’ kernel/power/user.c:254: error: implicit declaration of function ‘usermodehelper_disable’ kernel/power/user.c:261: error: implicit declaration of function ‘usermodehelper_enable’ kernel/sys.c:317: error: implicit declaration of function ‘usermodehelper_disable’ kernel/sys.c:1816: error: implicit declaration of function ‘call_usermodehelper_setup’ kernel/sys.c:1822: error: implicit declaration of function ‘call_usermodehelper_setfns’ kernel/sys.c:1824: error: implicit declaration of function ‘call_usermodehelper_exec’ Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: Add <linux/module.h> to files using it implicitlyPaul Gortmaker2011-10-312-0/+2
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | These files are doing things like module_put and try_module_get so they need to call out the module.h for explicit inclusion, rather than getting it via <linux/device.h> which we ideally want to remove the module.h inclusion from. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | kernel: Map most files to use export.h instead of module.hPaul Gortmaker2011-10-3161-61/+61
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | The changed files were only including linux/module.h for the EXPORT_SYMBOL infrastructure, and nothing else. Revector them onto the isolated export header for faster compile times. Nothing to see here but a whole lot of instances of: -#include <linux/module.h> +#include <linux/export.h> This commit is only changing the kernel dir; next targets will probably be mm, fs, the arch dirs, etc. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
| * | | range: fix bogus misuse of module.h to get printk()Paul Gortmaker2011-10-311-1/+1
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | This file isn't doing anything with modules and so it should not be including <linux/module.h> just to get basic stuff like printk() and min/max. Revector it to <linux/kernel.h>. Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
* | | | Merge branch 'writeback-for-linus' of ↵Linus Torvalds2011-11-061-0/+3
|\ \ \ \ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux * 'writeback-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/wfg/linux: writeback: Add a 'reason' to wb_writeback_work writeback: send work item to queue_io, move_expired_inodes writeback: trace event balance_dirty_pages writeback: trace event bdi_dirty_ratelimit writeback: fix ppc compile warnings on do_div(long long, unsigned long) writeback: per-bdi background threshold writeback: dirty position control - bdi reserve area writeback: control dirty pause time writeback: limit max dirty pause time writeback: IO-less balance_dirty_pages() writeback: per task dirty rate limit writeback: stabilize bdi->dirty_ratelimit writeback: dirty rate control writeback: add bg_threshold parameter to __bdi_update_bandwidth() writeback: dirty position control writeback: account per-bdi accumulated dirtied pages
| * | | | writeback: per task dirty rate limitWu Fengguang2011-10-031-0/+3
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | Add two fields to task_struct. 1) account dirtied pages in the individual tasks, for accuracy 2) per-task balance_dirty_pages() call intervals, for flexibility The balance_dirty_pages() call interval (ie. nr_dirtied_pause) will scale near-sqrt to the safety gap between dirty pages and threshold. The main problem of per-task nr_dirtied is, if 1k+ tasks start dirtying pages at exactly the same time, each task will be assigned a large initial nr_dirtied_pause, so that the dirty threshold will be exceeded long before each task reached its nr_dirtied_pause and hence call balance_dirty_pages(). The solution is to watch for the number of pages dirtied on each CPU in between the calls into balance_dirty_pages(). If it exceeds ratelimit_pages (3% dirty threshold), force call balance_dirty_pages() for a chance to set bdi->dirty_exceeded. In normal situations, this safeguarding condition is not expected to trigger at all. On the sqrt in dirty_poll_interval(): It will serve as an initial guess when dirty pages are still in the freerun area. When dirty pages are floating inside the dirty control scope [freerun, limit], a followup patch will use some refined dirty poll interval to get the desired pause time. thresh-dirty (MB) sqrt 1 16 2 22 4 32 8 45 16 64 32 90 64 128 128 181 256 256 512 362 1024 512 The above table means, given 1MB (or 1GB) gap and the dd tasks polling balance_dirty_pages() on every 16 (or 512) pages, the dirty limit won't be exceeded as long as there are less than 16 (or 512) concurrent dd's. So sqrt naturally leads to less overheads and more safe concurrent tasks for large memory servers, which have large (thresh-freerun) gaps. peter: keep the per-CPU ratelimit for safeguarding the 1k+ tasks case CC: Peter Zijlstra <a.p.zijlstra@chello.nl> Reviewed-by: Andrea Righi <andrea@betterlinux.com> Signed-off-by: Wu Fengguang <fengguang.wu@intel.com>
OpenPOWER on IntegriCloud