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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-locking-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
lockdep/waitqueues: Add better annotation
lockdep, bug: Exclude TAINT_OOT_MODULE from disabling lock debugging
lockdep: Print lock name in lockdep_init_error()
init/main.c: Execute lockdep_init() as early as possible
lockdep, kmemcheck: Annotate ->lock in lockdep_init_map()
lockdep, rtmutex, bug: Show taint flags on error
lockdep, bug: Exclude TAINT_FIRMWARE_WORKAROUND from disabling lockdep
lockdep: Always try to set ->class_cache in register_lock_class() lockdep_init_map()
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
* 'core-debugobjects-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
timer: Use debugobjects to catch deletion of uninitialized timers
timer: Setup uninitialized timer with a stub callback
debugobjects: Extend to assert that an object is initialized
debugobjects: Be smarter about static objects
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If we mount a hierarchy with a specified name, the name is unique,
and we can use it to mount the hierarchy without specifying its
set of subsystem names. This feature is documented is
Documentation/cgroups/cgroups.txt section 2.3
Here's an example:
# mount -t cgroup -o cpuset,name=myhier xxx /cgroup1
# mount -t cgroup -o name=myhier xxx /cgroup2
But it was broken by commit 32a8cf235e2f192eb002755076994525cdbaa35a
(cgroup: make the mount options parsing more accurate)
This fixes the regression.
Signed-off-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: [email protected]
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Conflicts:
arch/arm/kernel/setup.c
arch/arm/mach-shmobile/board-kota2.c
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* pm-sleep:
PM / Hibernate: Implement compat_ioctl for /dev/snapshot
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This allows uswsusp built for i386 to run on an x86_64 kernel (tested
with Debian package version 1.0+20110509-2).
References: http://bugs.debian.org/502816
Signed-off-by: Ben Hutchings <[email protected]>
Signed-off-by: Rafael J. Wysocki <[email protected]>
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This is the temporary simple fix for 3.2, we need more changes in this
area.
1. do_signal_stop() assumes that the running untraced thread in the
stopped thread group is not possible. This was our goal but it is
not yet achieved: a stopped-but-resumed tracee can clone the running
thread which can initiate another group-stop.
Remove WARN_ON_ONCE(!current->ptrace).
2. A new thread always starts with ->jobctl = 0. If it is auto-attached
and this group is stopped, __ptrace_unlink() sets JOBCTL_STOP_PENDING
but JOBCTL_STOP_SIGMASK part is zero, this triggers WANR_ON(!signr)
in do_jobctl_trap() if another debugger attaches.
Change __ptrace_unlink() to set the artificial SIGSTOP for report.
Alternatively we could change ptrace_init_task() to copy signr from
current, but this means we can copy it for no reason and hide the
possible similar problems.
Acked-by: Tejun Heo <[email protected]>
Cc: <[email protected]> [3.1]
Signed-off-by: Oleg Nesterov <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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Test-case:
int main(void)
{
int pid, status;
pid = fork();
if (!pid) {
for (;;) {
if (!fork())
return 0;
if (waitpid(-1, &status, 0) < 0) {
printf("ERR!! wait: %m\n");
return 0;
}
}
}
assert(ptrace(PTRACE_ATTACH, pid, 0,0) == 0);
assert(waitpid(-1, NULL, 0) == pid);
assert(ptrace(PTRACE_SETOPTIONS, pid, 0,
PTRACE_O_TRACEFORK) == 0);
do {
ptrace(PTRACE_CONT, pid, 0, 0);
pid = waitpid(-1, NULL, 0);
} while (pid > 0);
return 1;
}
It fails because ->real_parent sees its child in EXIT_DEAD state
while the tracer is going to change the state back to EXIT_ZOMBIE
in wait_task_zombie().
The offending commit is 823b018e which moved the EXIT_DEAD check,
but in fact we should not blame it. The original code was not
correct as well because it didn't take ptrace_reparented() into
account and because we can't really trust ->ptrace.
This patch adds the additional check to close this particular
race but it doesn't solve the whole problem. We simply can't
rely on ->ptrace in this case, it can be cleared if the tracer
is multithreaded by the exiting ->parent.
I think we should kill EXIT_DEAD altogether, we should always
remove the soon-to-be-reaped child from ->children or at least
we should never do the DEAD->ZOMBIE transition. But this is too
complex for 3.2.
Reported-and-tested-by: Denys Vlasenko <[email protected]>
Tested-by: Lukasz Michalik <[email protected]>
Acked-by: Tejun Heo <[email protected]>
Cc: <[email protected]> [3.0+]
Signed-off-by: Oleg Nesterov <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
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Gcc complains about this: "kernel/cgroup.c:2179:4: warning: suggest
parentheses around assignment used as truth value [-Wparentheses]"
Signed-off-by: Dan Carpenter <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
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Signed-off-by: Al Viro <[email protected]>
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Signed-off-by: Al Viro <[email protected]>
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Signed-off-by: Al Viro <[email protected]>
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Signed-off-by: Al Viro <[email protected]>
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Signed-off-by: Al Viro <[email protected]>
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vfs_mkdir() gets int, but immediately drops everything that might not
fit into umode_t and that's the only caller of ->mkdir()...
Signed-off-by: Al Viro <[email protected]>
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Move invalidate_bdev, block_sync_page into fs/block_dev.c. Export
kill_bdev as well, so brd doesn't have to open code it. Reduce
buffer_head.h requirement accordingly.
Removed a rather large comment from invalidate_bdev, as it looked a bit
obsolete to bother moving. The small comment replacing it says enough.
Signed-off-by: Nick Piggin <[email protected]>
Cc: Al Viro <[email protected]>
Cc: Christoph Hellwig <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Al Viro <[email protected]>
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... and clean it up a bit, while we are at it
Signed-off-by: Al Viro <[email protected]>
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vfork parent uninterruptibly and unkillably waits for its child to
exec/exit. This wait is of unbounded length. Ignore such waits
in the hung_task detector.
Signed-off-by: Mandeep Singh Baines <[email protected]>
Reported-by: Sasha Levin <[email protected]>
LKML-Reference: <1325344394.28904.43.camel@lappy>
Cc: Linus Torvalds <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: John Kacur <[email protected]>
Cc: [email protected]
Signed-off-by: Linus Torvalds <[email protected]>
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Signed-off-by: Al Viro <[email protected]>
Signed-off-by: Jiri Kosina <[email protected]>
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It was found (by Sasha) that if you use a futex located in the gate
area we get stuck in an uninterruptible infinite loop, much like the
ZERO_PAGE issue.
While looking at this problem, PeterZ realized you'll get into similar
trouble when hitting any install_special_pages() mapping. And are there
still drivers setting up their own special mmaps without page->mapping,
and without special VM or pte flags to make get_user_pages fail?
In most cases, if page->mapping is NULL, we do not need to retry at all:
Linus points out that even /proc/sys/vm/drop_caches poses no problem,
because it ends up using remove_mapping(), which takes care not to
interfere when the page reference count is raised.
But there is still one case which does need a retry: if memory pressure
called shmem_writepage in between get_user_pages_fast dropping page
table lock and our acquiring page lock, then the page gets switched from
filecache to swapcache (and ->mapping set to NULL) whatever the refcount.
Fault it back in to get the page->mapping needed for key->shared.inode.
Reported-by: Sasha Levin <[email protected]>
Signed-off-by: Hugh Dickins <[email protected]>
Cc: [email protected]
Signed-off-by: Linus Torvalds <[email protected]>
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This reverts commit de28f25e8244c7353abed8de0c7792f5f883588c.
It results in resume problems for various people. See for example
http://thread.gmane.org/gmane.linux.kernel/1233033
http://thread.gmane.org/gmane.linux.kernel/1233389
http://thread.gmane.org/gmane.linux.kernel/1233159
http://thread.gmane.org/gmane.linux.kernel/1227868/focus=1230877
and the fedora and ubuntu bug reports
https://bugzilla.redhat.com/show_bug.cgi?id=767248
https://bugs.launchpad.net/ubuntu/+source/linux/+bug/904569
which got bisected down to the stable version of this commit.
Reported-by: Jonathan Nieder <[email protected]>
Reported-by: Phil Miller <[email protected]>
Reported-by: Philip Langdale <[email protected]>
Reported-by: Tim Gardner <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Greg KH <[email protected]>
Cc: [email protected] # for stable kernels that applied the original
Signed-off-by: Linus Torvalds <[email protected]>
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A DT node may have more than 1 domain associated with it, so make sure
the hwirq number is within range when doing DT translation.
Signed-off-by: Rob Herring <[email protected]>
Acked-by: Grant Likely <[email protected]>
Acked-by: Shawn Guo <[email protected]>
Cc: Thomas Gleixner <[email protected]>
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cgroup_post_fork() is protected between threadgroup_change_begin()
and threadgroup_change_end() against concurrent changes of the
child's css_set in cgroup_task_migrate(). Also the child can't
exit and call cgroup_exit() at this stage, this means it's css_set
can't be changed with init_css_set concurrently.
For these reasons, we don't need to hold task_lock() on the child
because it's css_set can only remain stable in this place.
Let's remove the lock there.
v2: Update comment to explain that we are safe against
cgroup_exit()
Signed-off-by: Frederic Weisbecker <[email protected]>
Acked-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: Containers <[email protected]>
Cc: Cgroups <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Paul Menage <[email protected]>
Cc: Mandeep Singh Baines <[email protected]>
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Signed-off-by: Kirill A. Shutemov <[email protected]>
Acked-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
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Signed-off-by: Kirill A. Shutemov <[email protected]>
Acked-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
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* tip/perf/core: (66 commits)
perf, x86: Expose perf capability to other modules
perf, x86: Implement arch event mask as quirk
x86, perf: Disable non available architectural events
jump_label: Provide jump_label_key initializers
jump_label, x86: Fix section mismatch
perf, core: Rate limit perf_sched_events jump_label patching
perf: Fix enable_on_exec for sibling events
perf: Remove superfluous arguments
perf, x86: Prefer fixed-purpose counters when scheduling
perf, x86: Fix event scheduler for constraints with overlapping counters
perf, x86: Implement event scheduler helper functions
perf: Avoid a useless pmu_disable() in the perf-tick
x86/tools: Add decoded instruction dump mode
x86: Update instruction decoder to support new AVX formats
x86/tools: Fix insn_sanity message outputs
x86/tools: Fix instruction decoder message output
x86: Fix instruction decoder to handle grouped AVX instructions
x86/tools: Fix Makefile to build all test tools
perf test: Soft errors shouldn't stop the "Validate PERF_RECORD_" test
perf test: Validate PERF_RECORD_ events and perf_sample fields
...
Signed-off-by: Avi Kivity <[email protected]>
* commit 'b3d9468a8bd218a695e3a0ff112cd4efd27b670a': (66 commits)
perf, x86: Expose perf capability to other modules
perf, x86: Implement arch event mask as quirk
x86, perf: Disable non available architectural events
jump_label: Provide jump_label_key initializers
jump_label, x86: Fix section mismatch
perf, core: Rate limit perf_sched_events jump_label patching
perf: Fix enable_on_exec for sibling events
perf: Remove superfluous arguments
perf, x86: Prefer fixed-purpose counters when scheduling
perf, x86: Fix event scheduler for constraints with overlapping counters
perf, x86: Implement event scheduler helper functions
perf: Avoid a useless pmu_disable() in the perf-tick
x86/tools: Add decoded instruction dump mode
x86: Update instruction decoder to support new AVX formats
x86/tools: Fix insn_sanity message outputs
x86/tools: Fix instruction decoder message output
x86: Fix instruction decoder to handle grouped AVX instructions
x86/tools: Fix Makefile to build all test tools
perf test: Soft errors shouldn't stop the "Validate PERF_RECORD_" test
perf test: Validate PERF_RECORD_ events and perf_sample fields
...
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Export these two symbols, they will be used by KVM mmu audit
Signed-off-by: Xiao Guangrong <[email protected]>
Signed-off-by: Avi Kivity <[email protected]>
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* pm-sleep: (51 commits)
PM: Drop generic_subsys_pm_ops
PM / Sleep: Remove forward-only callbacks from AMBA bus type
PM / Sleep: Remove forward-only callbacks from platform bus type
PM: Run the driver callback directly if the subsystem one is not there
PM / Sleep: Make pm_op() and pm_noirq_op() return callback pointers
PM / Sleep: Merge internal functions in generic_ops.c
PM / Sleep: Simplify generic system suspend callbacks
PM / Hibernate: Remove deprecated hibernation snapshot ioctls
PM / Sleep: Fix freezer failures due to racy usermodehelper_is_disabled()
PM / Sleep: Recommend [un]lock_system_sleep() over using pm_mutex directly
PM / Sleep: Replace mutex_[un]lock(&pm_mutex) with [un]lock_system_sleep()
PM / Sleep: Make [un]lock_system_sleep() generic
PM / Sleep: Use the freezer_count() functions in [un]lock_system_sleep() APIs
PM / Freezer: Remove the "userspace only" constraint from freezer[_do_not]_count()
PM / Hibernate: Replace unintuitive 'if' condition in kernel/power/user.c with 'else'
Freezer / sunrpc / NFS: don't allow TASK_KILLABLE sleeps to block the freezer
PM / Sleep: Unify diagnostic messages from device suspend/resume
ACPI / PM: Do not save/restore NVS on Asus K54C/K54HR
PM / Hibernate: Remove deprecated hibernation test modes
PM / Hibernate: Thaw processes in SNAPSHOT_CREATE_IMAGE ioctl test path
...
Conflicts:
kernel/kmod.c
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* pm-misc:
CPU: Add right qualifiers for alloc_frozen_cpus() and cpu_hotplug_pm_sync_init()
PM / Usermodehelper: Cleanup remnants of usermodehelper_pm_callback()
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irqdomain support is used in interrupt controller drivers that may not
have device tree support but only need the basic HW->Linux irq
translation. Rather than having each of these implement their own IRQ
domain, allow them to use the simple ops.
Acked-by: Thomas Gleixner <[email protected]>
Acked-by: Rob Herring <[email protected]>
Cc: Grant Likely <[email protected]>
Signed-off-by: Jamie Iles <[email protected]>
Signed-off-by: Russell King <[email protected]>
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If CONFIG_SCHEDSTATS is defined, the kernel maintains
information about how long the task was sleeping or
in the case of iowait, blocking in the kernel before
getting woken up.
This will be useful for sleep time profiling.
Note: this information is only provided for sched_fair.
Other scheduling classes may choose to provide this in
the future.
Note: the delay includes the time spent on the runqueue
as well.
Signed-off-by: Arun Sharma <[email protected]>
Acked-by: Peter Zijlstra <[email protected]>
Cc: Steven Rostedt <[email protected]>
Cc: Mathieu Desnoyers <[email protected]>
Cc: Arnaldo Carvalho de Melo <[email protected]>
Cc: Andrew Vagin <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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The panic-on-framebuffer code seems to cause a schedule
to occur during an oops. This causes a bunch of extra
spew as can be seen in:
https://bugzilla.redhat.com/attachment.cgi?id=549230
Don't do scheduler debug checks when we are oopsing already.
Signed-off-by: Dave Jones <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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In cgroup_attach_proc it is now sufficient to only check that
oldcgrp==newcgrp once. Now that we are using threadgroup_lock()
during the migrations, oldcgrp will not change.
Signed-off-by: Mandeep Singh Baines <[email protected]>
Acked-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Paul Menage <[email protected]>
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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.
Changes in V2:
* https://lkml.org/lkml/2011/12/20/369 (Tejun Heo)
* Undo incorrect removal of get/put from attach_task_by_pid()
* Author
* Remove a comment which is made stale by this change
Signed-off-by: Mandeep Singh Baines <[email protected]>
Acked-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Paul Menage <[email protected]>
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We can now assume that the css_set reference held by the task
will not go away for an exiting task. PF_EXITING state can be
trusted throughout migration by checking it after locking
threadgroup.
Changes in V4:
* https://lkml.org/lkml/2011/12/20/368 (Tejun Heo)
* Fix typo in commit message
* Undid the rename of css_set_check_fetched
* https://lkml.org/lkml/2011/12/20/427 (Li Zefan)
* Fix comment in cgroup_task_migrate()
Changes in V3:
* https://lkml.org/lkml/2011/12/20/255 (Frederic Weisbecker)
* Fixed to put error in retval
Changes in V2:
* https://lkml.org/lkml/2011/12/19/289 (Tejun Heo)
* Updated commit message
-tj: removed stale patch description about dropped function rename.
Signed-off-by: Mandeep Singh Baines <[email protected]>
Acked-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Frederic Weisbecker <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Paul Menage <[email protected]>
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This isn't needed in the clockevents.c file, and the header file is
going away soon, so just remove the #include
Cc: Thomas Gleixner <[email protected]>
Signed-off-by: Kay Sievers <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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This moves the 'cpu sysdev_class' over to a regular 'cpu' subsystem
and converts the devices to regular devices. The sysdev drivers are
implemented as subsystem interfaces now.
After all sysdev classes are ported to regular driver core entities, the
sysdev implementation will be entirely removed from the kernel.
Userspace relies on events and generic sysfs subsystem infrastructure
from sysdev devices, which are made available with this conversion.
Cc: Haavard Skinnemoen <[email protected]>
Cc: Hans-Christian Egtvedt <[email protected]>
Cc: Tony Luck <[email protected]>
Cc: Fenghua Yu <[email protected]>
Cc: Arnd Bergmann <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Martin Schwidefsky <[email protected]>
Cc: Heiko Carstens <[email protected]>
Cc: Paul Mundt <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Chris Metcalf <[email protected]>
Cc: Thomas Gleixner <[email protected]>
Cc: Ingo Molnar <[email protected]>
Cc: "H. Peter Anvin" <[email protected]>
Cc: Borislav Petkov <[email protected]>
Cc: Tigran Aivazian <[email protected]>
Cc: Len Brown <[email protected]>
Cc: Zhang Rui <[email protected]>
Cc: Dave Jones <[email protected]>
Cc: Peter Zijlstra <[email protected]>
Cc: Russell King <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Arjan van de Ven <[email protected]>
Cc: "Rafael J. Wysocki" <[email protected]>
Cc: "Srivatsa S. Bhat" <[email protected]>
Signed-off-by: Kay Sievers <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
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* master: (848 commits)
SELinux: Fix RCU deref check warning in sel_netport_insert()
binary_sysctl(): fix memory leak
mm/vmalloc.c: remove static declaration of va from __get_vm_area_node
ipmi_watchdog: restore settings when BMC reset
oom: fix integer overflow of points in oom_badness
memcg: keep root group unchanged if creation fails
nilfs2: potential integer overflow in nilfs_ioctl_clean_segments()
nilfs2: unbreak compat ioctl
cpusets: stall when updating mems_allowed for mempolicy or disjoint nodemask
evm: prevent racing during tfm allocation
evm: key must be set once during initialization
mmc: vub300: fix type of firmware_rom_wait_states module parameter
Revert "mmc: enable runtime PM by default"
mmc: sdhci: remove "state" argument from sdhci_suspend_host
x86, dumpstack: Fix code bytes breakage due to missing KERN_CONT
IB/qib: Correct sense on freectxts increment and decrement
RDMA/cma: Verify private data length
cgroups: fix a css_set not found bug in cgroup_attach_proc
oprofile: Fix uninitialized memory access when writing to writing to oprofilefs
Revert "xen/pv-on-hvm kexec: add xs_reset_watches to shutdown watches from old kernel"
...
Conflicts:
kernel/cgroup_freezer.c
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When we fetch the css_set of the tasks on cgroup migration, we don't need
anymore to synchronize against cgroup_exit() that could swap the old one
with init_css_set. Now that we are using threadgroup_lock() during
the migrations, we don't need to worry about it anymore.
Signed-off-by: Frederic Weisbecker <[email protected]>
Reviewed-by: Mandeep Singh Baines <[email protected]>
Reviewed-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: Containers <[email protected]>
Cc: Cgroups <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Paul Menage <[email protected]>
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We don't need to hold the parent task_lock() on the
parent in cgroup_fork() because we are already synchronized
against the two places that may change the parent css_set
concurrently:
- cgroup_exit(), but the parent obviously can't exit concurrently
- cgroup migration: we are synchronized against threadgroup_lock()
So we can safely remove the task_lock() there.
Signed-off-by: Frederic Weisbecker <[email protected]>
Reviewed-by: Li Zefan <[email protected]>
Signed-off-by: Tejun Heo <[email protected]>
Cc: Containers <[email protected]>
Cc: Cgroups <[email protected]>
Cc: KAMEZAWA Hiroyuki <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Paul Menage <[email protected]>
Cc: Mandeep Singh Baines <[email protected]>
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There is a small race between try_to_wake_up() and sched_move_task(),
which is trying to move the process being woken up.
try_to_wake_up() on CPU0 sched_move_task() on CPU1
--------------------------------+---------------------------------
raw_spin_lock_irqsave(p->pi_lock)
task_waking_fair()
->p.se.vruntime -= cfs_rq->min_vruntime
ttwu_queue()
->send reschedule IPI to CPU1
raw_spin_unlock_irqsave(p->pi_lock)
task_rq_lock()
-> tring to aquire both p->pi_lock and
rq->lock with IRQ disabled
task_move_group_fair()
-> p.se.vruntime
-= (old)cfs_rq->min_vruntime
+= (new)cfs_rq->min_vruntime
task_rq_unlock()
(via IPI)
sched_ttwu_pending()
raw_spin_lock(rq->lock)
ttwu_do_activate()
...
enqueue_entity()
child.se->vruntime += cfs_rq->min_vruntime
raw_spin_unlock(rq->lock)
As a result, vruntime of the process becomes far bigger than min_vruntime,
if (new)cfs_rq->min_vruntime >> (old)cfs_rq->min_vruntime.
This patch fixes this problem by just ignoring such process in
task_move_group_fair(), because the vruntime has already been normalized in
task_waking_fair().
Signed-off-by: Daisuke Nishimura <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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There is a small race between do_fork() and sched_move_task(), which is
trying to move the child.
do_fork() sched_move_task()
--------------------------------+---------------------------------
copy_process()
sched_fork()
task_fork_fair()
-> vruntime of the child is initialized
based on that of the parent.
-> we can see the child in "tasks" file now.
task_rq_lock()
task_move_group_fair()
-> child.se.vruntime
-= (old)cfs_rq->min_vruntime
+= (new)cfs_rq->min_vruntime
task_rq_unlock()
wake_up_new_task()
...
enqueue_entity()
child.se.vruntime += cfs_rq->min_vruntime
As a result, vruntime of the child becomes far bigger than min_vruntime,
if (new)cfs_rq->min_vruntime >> (old)cfs_rq->min_vruntime.
This patch fixes this problem by just ignoring such process in
task_move_group_fair(), because the vruntime has already been normalized in
task_fork_fair().
Signed-off-by: Daisuke Nishimura <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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There is a small race between task_fork_fair() and sched_move_task(),
which is trying to move the parent.
task_fork_fair() sched_move_task()
--------------------------------+---------------------------------
cfs_rq = task_cfs_rq(current)
-> cfs_rq is the "old" one.
curr = cfs_rq->curr
-> curr is set to the parent.
task_rq_lock()
dequeue_task()
->parent.se.vruntime -= (old)cfs_rq->min_vruntime
enqueue_task()
->parent.se.vruntime += (new)cfs_rq->min_vruntime
task_rq_unlock()
raw_spin_lock_irqsave(rq->lock)
se->vruntime = curr->vruntime
-> vruntime of the child is set to that of the parent
which has already been updated by sched_move_task().
se->vruntime -= (old)cfs_rq->min_vruntime.
raw_spin_unlock_irqrestore(rq->lock)
As a result, vruntime of the child becomes far bigger than expected,
if (new)cfs_rq->min_vruntime >> (old)cfs_rq->min_vruntime.
This patch fixes this problem by setting "cfs_rq" and "curr" after
holding the rq->lock.
Signed-off-by: Daisuke Nishimura <[email protected]>
Acked-by: Paul Turner <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Tejun Heo <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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Remove cfs bandwidth period check from tg_set_cfs_period.
Invalid bandwidth period's lower/upper limits are denoted
by min_cfs_quota_period/max_cfs_quota_period repsectively,
and are checked against valid period in tg_set_cfs_bandwidth().
As pjt pointed out, negative input will result in very large unsigned
numbers and will be caught by the max allowed period test.
Signed-off-by: Kamalesh Babulal <[email protected]>
Acked-by: Paul Turner <[email protected]>
[ammended changelog to mention negative values]
Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
--
kernel/sched/core.c | 3 ---
1 file changed, 3 deletions(-)
Signed-off-by: Ingo Molnar <[email protected]>
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The current lock break relies on contention on the rq locks, something
which might never come because we've got IRQs disabled. Or will be
very likely because on anything with more than 2 cpus a synchronized
load-balance pass will very likely cause contention on the rq locks.
Also the sched_nr_migrate thing fails when it gets trapped the loops
of either the cgroup muck in load_balance_fair() or the move_tasks()
load condition.
Instead, use the new lb_flags field to propagate break/abort
conditions for all these loops and create a new loop outside the irq
disabled on the break being required.
Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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Replace the all_pinned argument with a flags field so that we can add
some extra controls throughout that entire call chain.
Signed-off-by: Peter Zijlstra <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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Mike reported a 13% drop in netperf TCP_RR performance due to the
new remote wakeup code. Suresh too noticed some performance issues
with it.
Reducing the IPIs to only cross cache domains solves the observed
performance issues.
Reported-by: Suresh Siddha <[email protected]>
Reported-by: Mike Galbraith <[email protected]>
Acked-by: Suresh Siddha <[email protected]>
Acked-by: Mike Galbraith <[email protected]>
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Chris Mason <[email protected]>
Cc: Dave Kleikamp <[email protected]>
Link: http://lkml.kernel.org/r/1323338531.17673.7.camel@twins
Signed-off-by: Ingo Molnar <[email protected]>
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-> #2 (&tty->write_wait){-.-...}:
is a lot more informative than:
-> #2 (key#19){-.....}:
Signed-off-by: Peter Zijlstra <[email protected]>
Cc: Andrew Morton <[email protected]>
Cc: Linus Torvalds <[email protected]>
Link: http://lkml.kernel.org/n/[email protected]
Signed-off-by: Ingo Molnar <[email protected]>
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Merge reason: Pick up the latest fixes.
Signed-off-by: Ingo Molnar <[email protected]>
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