There is no need to zero struct sched_group member cpumask and struct
sched_group_power member power since both structures are already allocated
as zeroed memory in __sdt_alloc().
This patch has been tested with
BUG_ON(!cpumask_empty(sched_group_cpus(sg))); and BUG_ON(sg->sgp->power);
in build_sched_groups() on ARM TC2 and INTEL i5 M520 platform including
CPU hotplug scenarios.
Signed-off-by: Dietmar Eggemann <dietmar.eggemann@arm.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/1398865178-12577-1-git-send-email-dietmar.eggemann@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Jet Chen has reported a kernel panics when booting qemu-system-x86_64 with
kvm64 cpu. A panic occured while building the sched_domain.
In sched_init_numa, we create a new topology table in which both default
levels and numa levels are copied. The last row of the table must have a null
pointer in the mask field.
The current implementation doesn't add this last row in the computation of the
table size. So we add 1 row in the allocation size that will be used as the
last row of the table. The kzalloc will ensure that the mask field is NULL.
Reported-by: Jet Chen <jet.chen@intel.com>
Tested-by: Jet Chen <jet.chen@intel.com>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: fengguang.wu@intel.com
Link: http://lkml.kernel.org/r/1399972261-25693-1-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
On smaller systems, the top level sched domain will be an affine
domain, and select_idle_sibling is invoked for every SD_WAKE_AFFINE
wakeup. This seems to be working well.
On larger systems, with the node distance between far away NUMA nodes
being > RECLAIM_DISTANCE, select_idle_sibling is only called if the
waker and the wakee are on nodes less than RECLAIM_DISTANCE apart.
This patch leaves in place the policy of not pulling the task across
nodes on such systems, while fixing the issue that select_idle_sibling
is not called at all in certain circumstances.
The code will look for an idle CPU in the same CPU package as the
CPU where the task ran previously.
Signed-off-by: Rik van Riel <riel@redhat.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: morten.rasmussen@arm.com
Cc: george.mccollister@gmail.com
Cc: ktkhai@parallels.com
Cc: Mel Gorman <mgorman@suse.de>
Cc: Mike Galbraith <umgwanakikbuti@gmail.com>
Link: http://lkml.kernel.org/r/20140514114037.2d93266f@annuminas.surriel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The logic in this function is a little contorted, clean it up:
* Rather than having chained gotos for the -EFBIG case, just
return -EFBIG directly.
* Now, the label 'out' is no longer needed, and 'ret' must be zero
zero by the time we fall through to this point, so just return 0.
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/536CEC24.9080201@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
task_hot checks exec_start on any runnable task, but if it has been
migrated since the it last ran, then exec_start is a clock_task from
another cpu. If the old cpu's clock_task was sufficiently far ahead of
this cpu's then the task will not be considered for another migration
until it has run. Instead reset exec_start whenever a task is migrated,
since it is presumably no longer hot anyway.
Signed-off-by: Ben Segall <bsegall@google.com>
[ Made it compile. ]
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140515225920.7179.13924.stgit@sword-of-the-dawn.mtv.corp.google.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Meta idle function jumps into the interrupt handler which
efficiently blocks waiting for the next interrupt when it reads the
interrupt status register (TXSTATI). No other (polling) idle functions
can be used, therefore TIF_POLLING_NRFLAG is unnecessary, so lets remove
it.
Peter Zijlstra said:
> Most archs have (x86) hlt or (arm) wfi like idle instructions, and if
> that is your only possible idle function, you'll require the interrupt
> to wake up and there's really no point to having the POLLING bit.
Signed-off-by: James Hogan <james.hogan@imgtec.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Link: http://lkml.kernel.org/r/536CEB7E.9080007@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Michael Kerrisk noticed that creating SCHED_DEADLINE reservations
with certain parameters (e.g, a runtime of something near 2^64 ns)
can cause a system freeze for some amount of time.
The problem is that in the interface we have
u64 sched_runtime;
while internally we need to have a signed runtime (to cope with
budget overruns)
s64 runtime;
At the time we setup a new dl_entity we copy the first value in
the second. The cast turns out with negative values when
sched_runtime is too big, and this causes the scheduler to go crazy
right from the start.
Moreover, considering how we deal with deadlines wraparound
(s64)(a - b) < 0
we also have to restrict acceptable values for sched_{deadline,period}.
This patch fixes the thing checking that user parameters are always
below 2^63 ns (still large enough for everyone).
It also rewrites other conditions that we check, since in
__checkparam_dl we don't have to deal with deadline wraparounds
and what we have now erroneously fails when the difference between
values is too big.
Reported-by: Michael Kerrisk <mtk.manpages@gmail.com>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Juri Lelli <juri.lelli@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Dario Faggioli<raistlin@linux.it>
Cc: Dave Jones <davej@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/20140513141131.20d944f81633ee937f256385@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The documented[1] behavior of sched_attr() in the proposed man page text is:
sched_attr::size must be set to the size of the structure, as in
sizeof(struct sched_attr), if the provided structure is smaller
than the kernel structure, any additional fields are assumed
'0'. If the provided structure is larger than the kernel structure,
the kernel verifies all additional fields are '0' if not the
syscall will fail with -E2BIG.
As currently implemented, sched_copy_attr() returns -EFBIG for
for this case, but the logic in sys_sched_setattr() converts that
error to -EFAULT. This patch fixes the behavior.
[1] http://thread.gmane.org/gmane.linux.kernel/1615615/focus=1697760
Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
Signed-off-by: Peter Zijlstra <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Link: http://lkml.kernel.org/r/536CEC17.9070903@gmail.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull two powerpc fixes from Ben Herrenschmidt:
"Here are a couple of fixes for 3.15. One from Anton fixes a nasty
regression I introduced when trying to fix a loss of irq_work whose
consequences is that we can completely lose timer interrupts on a
CPU... not pretty.
The other one is a change to our PCIe reset hook to use a firmware
call instead of direct config space accesses to trigger a fundamental
reset on the root port. This is necessary so that the FW gets a
chance to disable the link down error monitoring, which would
otherwise trip and cause subsequent fatal EEH error"
* 'merge' of git://git.kernel.org/pub/scm/linux/kernel/git/benh/powerpc:
powerpc: irq work racing with timer interrupt can result in timer interrupt hang
powerpc/powernv: Reset root port in firmware
Pull two btrfs fixes from Chris Mason:
"This has two fixes that we've been testing for 3.16, but since both
are safe and fix real bugs, it makes sense to send for 3.15 instead"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
Btrfs: send, fix incorrect ref access when using extrefs
Btrfs: fix EIO on reading file after ioctl clone works on it
Pull two ceph fixes from Sage Weil:
"The first patch fixes a problem when we have a page count of 0 for
sendpage which is triggered by zfs. The second fixes a bug in CRUSH
that was resolved in the userland code a while back but fell through
the cracks on the kernel side"
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph-client:
crush: decode and initialize chooseleaf_vary_r
libceph: fix corruption when using page_count 0 page in rbd
Pull xfs fixes from Dave Chinner:
"Code inspection of the XFS error number sign translations found a
bunch of issues, including returning incorrectly signed errors for
some data integrity operations.
These leak to userspace and result in applications not getting the
errors correctly reported. Hence they need fixing sooner rather than
later.
A couple of the bugs are in data integrity operations, a couple more
are in the new COLLAPSE_RANGE code. One of these came in through a
recent ext4 merge and so I had to update the base tree to 3.15-rc5
before fixing the issues"
* tag 'xfs-for-linus-3.15-rc6' of git://oss.sgi.com/xfs/xfs:
xfs: list_lru_init returns a negative error
xfs: negate xfs_icsb_init_counters error value
xfs: negate mount workqueue init error value
xfs: fix wrong err sign on xfs_set_acl()
xfs: fix wrong errno from xfs_initxattrs
xfs: correct error sign on COLLAPSE_RANGE errors
xfs: xfs_commit_metadata returns wrong errno
xfs: fix incorrect error sign in xfs_file_aio_read
xfs: xfs_dir_fsync() returns positive errno
Pull renameat2 arch support from Miklos Szeredi:
"I've collected architecture patches for the renameat2 syscall that
maintainers acked and/or asked me to queue.
This adds architecture support for the renameat2 syscall to m68k,
parisc, ia64 and through asm-generic to arc, arm64, c6x, hexagon,
metag, openrisc, score, tile, unicore32"
* 'renameat2' of git://git.kernel.org/pub/scm/linux/kernel/git/mszeredi/vfs:
scripts/checksyscalls.sh: Make renameat optional
asm-generic: Add renameat2 syscall
ia64: add renameat2 syscall
parisc: add renameat2 syscall
m68k: add renameat2 syscall
Dongsheng Yang
Dietmar Eggemann
Vincent Guittot
Rik van Riel
Michael Kerrisk
Ben Segall
Ingo Molnar
Peter Zijlstra
James Hogan
Lai Jiangshan
Juri Lelli
Linus Torvalds