This patch corrects the incorrect value of per process run-queue wait
time reported by delay statistics. The anomaly was due to the following
reason. When a process leaves the CPU and immediately starts waiting for
CPU on the runqueue (which means it remains in the TASK_RUNNABLE state),
the time of re-entry into the run-queue is never recorded. Due to this,
the waiting time on the runqueue from this point of re-entry upto the
next time it hits the CPU is not accounted for. This is solved by
recording the time of re-entry of a process leaving the CPU in the
sched_info_depart() function IF the process will go back to waiting on
the run-queue. This IF condition is verified by checking whether the
process is still in the TASK_RUNNABLE state.
The patch was tested on 2.6.26-rc6 using two simple CPU hog programs.
The values noted prior to the fix did not account for the time spent on
the runqueue waiting. After the fix, the correct values were reported
back to user space.
Signed-off-by: Bharath Ravi <bharathravi1@gmail.com>
Signed-off-by: Madhava K R <madhavakr@gmail.com>
Cc: dhaval@linux.vnet.ibm.com
Cc: vatsa@in.ibm.com
Cc: balbir@in.ibm.com
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
First issue is not related to the cpusets. We're simply leaking doms_cur.
It's allocated in arch_init_sched_domains() which is called for every
hotplug event. So we just keep reallocation doms_cur without freeing it.
I introduced free_sched_domains() function that cleans things up.
Second issue is that sched domains created by the cpusets are
completely destroyed by the CPU hotplug events. For all CPU hotplug
events scheduler attaches all CPUs to the NULL domain and then puts
them all into the single domain thereby destroying domains created
by the cpusets (partition_sched_domains).
The solution is simple, when cpusets are enabled scheduler should not
create default domain and instead let cpusets do that. Which is
exactly what the patch does.
Signed-off-by: Max Krasnyansky <maxk@qualcomm.com>
Cc: pj@sgi.com
Cc: menage@google.com
Cc: rostedt@goodmis.org
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
In tick_task_rt() we first call update_curr_rt() which can dequeue a runqueue
due to it running out of runtime, and then we try to requeue it, of it also
having exhausted its RR quota. Obviously requeueing something that is no longer
on the runqueue will not have the expected result.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Daniel K. <dk@uw.no>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The bandwidth throttle code dequeues a group when it runs out of quota, and
re-queues it once the period rolls over and the quota gets refreshed.
Sadly it failed to take the hierarchy into consideration. Share more of the
enqueue/dequeue code with regular task opterations.
Also, some operations like sched_setscheduler() can dequeue/enqueue tasks that
are in throttled runqueues, we should not inadvertly re-enqueue empty runqueues
so check for that.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Daniel K. <dk@uw.no>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Don't re-set the entity's runqueue to the wrong rq after we've set it
to the right one.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Tested-by: Daniel K. <dk@uw.no>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Commit 62c96b9d09 ("agp/intel: cleanup
some serious whitespace badness") didn't just fix whitespace. It also
lost two lines.
Noticed by Linus. No more whitespace diffs for me.
Signed-off-by: Dave Airlie <airlied@redhat.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* 'agp-patches' of git://git.kernel.org/pub/scm/linux/kernel/git/airlied/agp-2.6:
agp/intel: cleanup some serious whitespace badness
[AGP] intel_agp: Add support for Intel 4 series chipsets
[AGP] intel_agp: extra stolen mem size available for IGD_GM chipset
agp: more boolean conversions.
drivers/char/agp - use bool
agp: two-stage page destruction issue
agp/via: fixup pci ids
This adds missing stolen memory size detect for IGD_GM, be sure to
detect right size as current X intel driver (2.3.2) which has already
worked out.
Signed-off-by: Zhenyu Wang <zhenyu.z.wang@intel.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
besides it apparently being useful only in 2.6.24 (the changes in 2.6.25
really mean that it could be converted back to a single-stage mechanism),
I'm seeing an issue in Xen Dom0 kernels, which is caused by the calling
of gart_to_virt() in the second stage invocations of the destroy function.
I think that besides this being a real issue with Xen (where
unmap_page_from_agp() is not just a page table attribute change), this
also is invalid from a theoretical perspective: One should not assume that
gart_to_virt() is still valid after unmapping a page. So minimally (keeping
the 2-stage mechanism) a patch like the one below would be needed.
Jan
Signed-off-by: Dave Airlie <airlied@redhat.com>
add a new PCI ID and remove an old dodgy one, include the explaination
in the commented code so nobody readds later.
(davej also sent the pci id addition).
Signed-off-by: Dave Airlie <airlied@redhat.com>
* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/roland/infiniband:
IB/uverbs: Fix check of is_closed flag check in ib_uverbs_async_handler()
RDMA/nes: Fix off-by-one in nes_reg_user_mr() error path
Commit 1ae5c187 ("IB/uverbs: Don't store struct file * for event
files") changed the way that closed files are handled in the uverbs
code. However, after the conversion, is_closed flag is checked
incorrectly in ib_uverbs_async_handler(). As a result, no async
events are ever passed to applications.
Found by: Ronni Zimmerman <ronniz@mellanox.co.il>
Signed-off-by: Jack Morgenstein <jackm@dev.mellanox.co.il>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
* git://git.kernel.org/pub/scm/linux/kernel/git/jejb/scsi-rc-fixes-2.6:
[SCSI] dpt_i2o: Add PROC_IA64 define
[SCSI] scsi_host regression: fix scsi host leak
[SCSI] sr: fix corrupt CD data after media change and delay
When we demote a slice from 64k to 4k, and we are about to insert an
HPTE for a 4k subpage and we notice that there is an existing 64k
HPTE, we first invalidate that HPTE before inserting the new 4k
subpage HPTE. Since the bits that encode which hash bucket the old
HPTE was in overlap with the bits that encode which of the 16 subpages
have HPTEs, we need to clear out the subpage HPTE-present bits before
starting to insert HPTEs for the 4k subpages. If we don't do that, we
can erroneously think that a subpage already has an HPTE when it
doesn't.
That in itself wouldn't be such a problem except that when we go to
update the HPTE that we think is present on machines with a
hypervisor, the hypervisor can tell us that the HPTE we think is there
is actually there even though it isn't, which can lead to a process
getting stuck in a loop, continually faulting. The reason for the
confusion is that the AVPN (abbreviated virtual page number) we are
looking for in the HPTE for a 4k subpage can actually match the AVPN
in a stale HPTE for another 64k page. For example, the HPTE for
the 4k subpage at 0x84000f000 will be in the same hash bucket and have
the same AVPN as the HPTE for the 64k page at 0x8400f0000.
This fixes the code to clear out the subpage HPTE-present bits.
Signed-off-by: Paul Mackerras <paulus@samba.org>
Bharath Ravi
Ingo Molnar
Max Krasnyansky
Peter Zijlstra
Dario Faggioli
Dave Airlie
Linus Torvalds
Zhenyu Wang
Joe Perches
Jan Beulich
Greg KH
Jack Morgenstein
Wim Van Sebroeck
Paul Mackerras