Optionally add a boot delay after each kernel printk() call, crudely
measured in milliseconds, with a maximum delay of 10 seconds per printk.
Enable CONFIG_BOOT_PRINTK_DELAY=y and then add (e.g.):
"lpj=loops_per_jiffy boot_delay=100"
to the kernel command line.
It has been useful in cases like "during boot, my machine just reboots or the
screen goes black" by slowing down printk, (and adding initcall_debug), we can
usually see the last thing that happened before the lights went out which is
usually a valuable clue.
[akpm@linux-foundation.org: not all architectures implement CONFIG_HZ]
[akpm@linux-foundation.org: fix lots of stuff]
[bunk@stusta.de: kernel/printk.c: make 2 variables static]
[heiko.carstens@de.ibm.com: fix slow down printk on boot compile error]
Signed-off-by: Randy Dunlap <rdunlap@xenotime.net>
Signed-off-by: Dave Jones <davej@redhat.com>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Heiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Identical handlers of PTRACE_DETACH go into ptrace_request().
Not touching compat code.
Not touching archs that don't call ptrace_request.
Signed-off-by: Alexey Dobriyan <adobriyan@sw.ru>
Acked-by: Christoph Hellwig <hch@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
* git://git.linux-nfs.org/pub/linux/nfs-2.6: (131 commits)
NFSv4: Fix a typo in nfs_inode_reclaim_delegation
NFS: Add a boot parameter to disable 64 bit inode numbers
NFS: nfs_refresh_inode should clear cache_validity flags on success
NFS: Fix a connectathon regression in NFSv3 and NFSv4
NFS: Use nfs_refresh_inode() in ops that aren't expected to change the inode
SUNRPC: Don't call xprt_release in call refresh
SUNRPC: Don't call xprt_release() if call_allocate fails
SUNRPC: Fix buggy UDP transmission
[23/37] Clean up duplicate includes in
[2.6 patch] net/sunrpc/rpcb_clnt.c: make struct rpcb_program static
SUNRPC: Use correct type in buffer length calculations
SUNRPC: Fix default hostname created in rpc_create()
nfs: add server port to rpc_pipe info file
NFS: Get rid of some obsolete macros
NFS: Simplify filehandle revalidation
NFS: Ensure that nfs_link() returns a hashed dentry
NFS: Be strict about dentry revalidation when doing exclusive create
NFS: Don't zap the readdir caches upon error
NFS: Remove the redundant nfs_reval_fsid()
NFSv3: Always use directory post-op attributes in nfs3_proc_lookup
...
Fix up trivial conflict due to sock_owned_by_user() cleanup manually in
net/sunrpc/xprtsock.c
make sure sync wakeups preempt too - the scheduler will not
overschedule as we've got various throttles against that.
As a result, sync wakeups can be used more widely in the kernel
(to signal wakeup affinity between tasks), and no arbitrary
latencies will be introduced either.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
make sync wakeups affine for cache-cold tasks: if a cache-cold task
is woken up by a sync wakeup then use the opportunity to migrate it
straight away. (the two tasks are 'related' because they communicate)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
modify account_system_time() to add cputime to cpustat->guest if we are
running a VCPU. We add this cputime to cpustat->user instead of
cpustat->system because this part of KVM code is in fact user code
although it is executed in the kernel. We duplicate VCPU time between
guest and user to allow an unmodified "top(1)" to display correct value.
A modified "top(1)" is able to display good cpu user time and cpu guest
time by subtracting cpu guest time from cpu user time. Update "gtime" in
task_struct accordingly.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Acked-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
like for cpustat, introduce the "gtime" (guest time of the task) and
"cgtime" (guest time of the task children) fields for the
tasks. Modify signal_struct and task_struct.
Modify /proc/<pid>/stat to display these new fields.
Signed-off-by: Laurent Vivier <Laurent.Vivier@bull.net>
Acked-by: Avi Kivity <avi@qumranet.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
we had an incorrect-terminator bug in sd_alloc_ctl_domain_table()
before, so add a comment that documents it.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Now that we are calling this at runtime, a more relaxed error path is
suggested. If an allocation fails, we just register the partial table,
which will show empty directories.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Unregister and free the sysctl table before destroying domains, then
rebuild and register after creating the new domains. This prevents the
sysctl table from pointing to freed memory for root to write.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
init_sched_domain_sysctl was walking cpus 0-n and referencing per_cpu
variables. If the cpus_possible mask is not contigious this will result
in a crash referencing unallocated data. If the online mask is not
contigious then we would show offline cpus and miss online ones.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
kcalloc checks for n * sizeof(element) overflows and it zeros.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
In general, struct file_operations are const in the kernel, to not have
false cacheline sharing and to catch bugs at compiletime with accidental
writes to them. The new scheduler code introduces a new non-const one;
fix this up.
Signed-off-by: Arjan van de Ven <arjan@linux.intel.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
activate task_hot() only for fair-scheduled tasks (i.e. disable it
for RT tasks).
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
reintroduce a simplified version of cache-hot/cold scheduling
affinity. This improves performance with certain SMP workloads,
such as sysbench.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
speed up context-switches a bit by not clearing p->exec_start.
(as a side-effect, this also makes p->exec_start a universal timestamp
available to cache-hot estimations.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Generate uevents when a user is being created/destroyed. These events
can be used to configure cpu share of a new user.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
do not normalize kernel threads via SysRq-N: the migration threads,
softlockup threads, etc. might be essential for the system to
function properly. So only zap user tasks.
pointed out by Andi Kleen.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
remove stale comment from sched_group_set_shares().
Function never returns -EINVAL.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Replace a particularly ugly ifdef with an inline and a new macro.
Also split up the function to be easier to read.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Refactor common code of sleep_on / wait_for_completion
These functions were largely cut'n'pasted. This moves
the common code into single helpers instead. Advantage
is about 1k less code on x86-64 and 91 lines of code removed.
It adds one function call to the non timeout version of
the functions; i don't expect this to be measurable.
Signed-off-by: Andi Kleen <ak@suse.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Prevent wakeup over-scheduling. Once a task has been preempted by a
task of the same or lower priority, it becomes ineligible for repeated
preemption by same until it has been ticked, or slept. Instead, the
task is marked for preemption at the next tick. Tasks of higher
priority still preempt immediately.
Signed-off-by: Mike Galbraith <efault@gmx.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Implement feature bit to disable forced preemption. This way
it can be checked whether a workload is overscheduling or not.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
The following patch (sched: disable sleeper_fairness on SCHED_BATCH)
seems to break GROUP_SCHED. Although, it may be 'oops'-less due to the
possibility of 'p' being always a valid address.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
cache_nice_tries and flags entry do not appear in proc fs sched_domain
directory, because ctl_table entry is skipped.
This patch fixes the issue.
Signed-off-by: Zou Nan hai <nanhai.zou@intel.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
yield() in wait_task_inactive(), can cause a high priority thread to be
scheduled back in, and there by loop forever while it is waiting for some
lower priority thread which is unfortunately still on the runqueue.
Use schedule_timeout_uninterruptible(1) instead.
Signed-off-by: Gautham R Shenoy <ego@in.ibm.com>
Credit: Oleg Nesterov <oleg@tv-sign.ru>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Add tunables in sysfs to modify a user's cpu share.
A directory is created in sysfs for each new user in the system.
/sys/kernel/uids/<uid>/cpu_share
Reading this file returns the cpu shares granted for the user.
Writing into this file modifies the cpu share for the user. Only an
administrator is allowed to modify a user's cpu share.
Ex:
# cd /sys/kernel/uids/
# cat 512/cpu_share
1024
# echo 2048 > 512/cpu_share
# cat 512/cpu_share
2048
#
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
disable sleeper fairness for batch tasks - they are about
batch processing after all.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
unit mis-match: wakeup_gran was used against a vruntime
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
export cpu_clock() - the preferred API instead of sched_clock().
Signed-off-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
noticed by Peter Zijlstra:
fix: move the CPU check into ->task_new_fair(), this way we
can call place_entity() and get child ->vruntime right at
initial wakeup time.
(without this there can be large latencies)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
kfree(NULL) is valid.
pointed out by checkpatch.pl.
the fix shrinks the code a bit:
text data bss dec hex filename
40024 3842 100 43966 abbe sched.o.before
40002 3842 100 43944 aba8 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
run sched_domain_debug() if CONFIG_SCHED_DEBUG=y, instead
of relying on the hand-crafted SCHED_DOMAIN_DEBUG switch.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
- make timeslices of SCHED_RR tasks constant and not
dependent on task's static_prio [1] ;
- remove obsolete code (timeslice related bits);
- make sched_rr_get_interval() return something more
meaningful [2] for SCHED_OTHER tasks.
[1] according to the following link, it's not compliant with SUSv3
(not sure though, what is the reference for us :-)
http://lkml.org/lkml/2007/3/7/656
[2] the interval is dynamic and can be depicted as follows "should a
task be one of the runnable tasks at this particular moment, it would
expect to run for this interval of time before being re-scheduled by the
scheduler tick".
(i.e. it's more precise if a task is runnable at the moment)
yeah, this seems to require task_rq_lock/unlock() but this is not a hot
path.
results:
(SCHED_FIFO)
dimm@earth:~/storage/prog$ sudo chrt -f 10 ./rr_interval
time_slice: 0 : 0
(SCHED_RR)
dimm@earth:~/storage/prog$ sudo chrt 10 ./rr_interval
time_slice: 0 : 99984800
(SCHED_NORMAL)
dimm@earth:~/storage/prog$ ./rr_interval
time_slice: 0 : 19996960
(SCHED_NORMAL + a cpu_hog of similar 'weight' on the same CPU --- so should be a half of the previous result)
dimm@earth:~/storage/prog$ taskset 1 ./rr_interval
time_slice: 0 : 9998480
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
optimize schedule() a bit on SMP, by moving the rq-clock update
outside the rq lock.
code size is the same:
text data bss dec hex filename
25725 2666 96 28487 6f47 sched.o.before
25725 2666 96 28487 6f47 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
The thing is that __pick_next_entity() must never be called when
first_fair(cfs_rq) == NULL. It wouldn't be a problem, should 'run_node'
be the very first field of 'struct sched_entity' (and it's the second).
The 'nr_running != 0' check is _not_ enough, due to the fact that
'current' is not within the tree. Generic paths are ok (e.g. schedule()
as put_prev_task() is called previously)... I'm more worried about e.g.
migration_call() -> CPU_DEAD_FROZEN -> migrate_dead_tasks()... if
'current' == rq->idle, no problems.. if it's one of the SCHED_NORMAL
tasks (or imagine, some other use-cases in the future -- i.e. we should
not make outer world dependent on internal details of sched_fair class)
-- it may be "Houston, we've got a problem" case.
it's +16 bytes to the ".text". Another variant is to make 'run_node' the
first data member of 'struct sched_entity' but an additional check (se !
= NULL) is still needed in pick_next_entity().
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Make vslice accurate wrt nice levels, and add some comments
while we're at it.
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
mark scheduling classes as const. The speeds up the code
a bit and shrinks it:
text data bss dec hex filename
40027 4018 292 44337 ad31 sched.o.before
40190 3842 292 44324 ad24 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
There is a possibility that because of task of a group moving from one
cpu to another, it may gain more cpu time that desired. See
http://marc.info/?l=linux-kernel&m=119073197730334 for details.
This is an attempt to fix that problem. Basically it simulates dequeue
of higher level entities as if they are going to sleep. Similarly it
simulate wakeup of higher level entities as if they are waking up from
sleep.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
group scheduler SMP migration fix: use task_cfs_rq(p) to get
to the relevant fair-scheduling runqueue of a task, rq->cfs
is not the right one.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
rename all 'cnt' fields and variables to the less yucky 'count' name.
yuckage noticed by Andrew Morton.
no change in code, other than the /proc/sched_debug bkl_count string got
a bit larger:
text data bss dec hex filename
38236 3506 24 41766 a326 sched.o.before
38240 3506 24 41770 a32a sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix yield bugs due to the current-not-in-rbtree changes: the task is
not in the rbtree so rbtree-removal is a no-no.
[ From: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>: build fix. ]
also, nice code size reduction:
kernel/sched.o:
text data bss dec hex filename
38323 3506 24 41853 a37d sched.o.before
38236 3506 24 41766 a326 sched.o.after
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
group scheduler wakeup latency fix: when checking for preemption
we must check cross-group too, not just intra-group.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Lee Schermerhorn noticed that set_leftmost() contains dead code,
remove this.
Reported-by: Lee Schermerhorn <Lee.Schermerhorn@hp.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
The adjusting sched_class is a missing part of the already existing "do
not leak PI boosting priority to the child" at the sched_fork(). This
patch moves the adjusting sched_class from wake_up_new_task() to
sched_fork().
this also shrinks the code a bit:
text data bss dec hex filename
40111 4018 292 44421 ad85 sched.o.before
40102 4018 292 44412 ad7c sched.o.after
Signed-off-by: Hiroshi Shimamoto <h-shimamoto@ct.jp.nec.com>
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix sched_fork(): large latencies at new task creation time because
the ->vruntime was not fixed up cross-CPU, if the parent got migrated
after the child's CPU got set up.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix sign check error in place_entity() - we'd get excessive
latencies due to negatives being converted to large u64's.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
undo some of the recent changes that are not needed after all,
such as last_min_vruntime.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
remove condition from set_task_cpu(). Now that ->vruntime
is not global anymore, it should (and does) work fine without
it too.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
entity_key() fix - we'd occasionally end up with a 0 vruntime
in the !initial case.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
debug feature: check how well we schedule within a reasonable
vruntime 'spread' range. (note that CPU overload can increase
the spread, so this is not a hard condition, but normal loads
should be within the spread.)
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
more width for parameter printouts in /proc/sched_debug.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
add vslice: the load-dependent "virtual slice" a task should
run ideally, so that the observed latency stays within the
sched_latency window.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
print the current value of all tunables in /proc/sched_debug output.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
add per task and per rq BKL usage statistics.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Enable user-id based fair group scheduling. This is useful for anyone
who wants to test the group scheduler w/o having to enable
CONFIG_CGROUPS.
A separate scheduling group (i.e struct task_grp) is automatically created for
every new user added to the system. Upon uid change for a task, it is made to
move to the corresponding scheduling group.
A /proc tunable (/proc/root_user_share) is also provided to tune root
user's quota of cpu bandwidth.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
With the view of supporting user-id based fair scheduling (and not just
container-based fair scheduling), this patch renames several functions
and makes them independent of whether they are being used for container
or user-id based fair scheduling.
Also fix a problem reported by KAMEZAWA Hiroyuki (wrt allocating
less-sized array for tg->cfs_rq[] and tf->se[]).
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
- Print &rq->cfs statistics as well (useful for group scheduling)
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
- print nr_running and load information for cfs_rq in /proc/sched_debug
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
- fix a minor bug in yield (seen for CONFIG_FAIR_GROUP_SCHED),
group scheduling would skew when yield was called.
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
enhance debug output by changing 12345678 nsecs to 12.345678 output,
this is more human-readable.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
print the correct amount of dashes in /proc/sched_debug.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
the 'p' (task_struct) parameter in the sched_class :: yield_task() is
redundant as the caller is always the 'current'. Get rid of it.
text data bss dec hex filename
24341 2734 20 27095 69d7 sched.o.before
24330 2734 20 27084 69cc sched.o.after
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
due to the fact that we no longer keep the 'current' within the tree,
dequeue/enqueue_entity() is useless for the 'current' in
task_new_fair(). We are about to reschedule and
sched_class->put_prev_task() will put the 'current' back into the tree,
based on its new key.
text data bss dec hex filename
24388 2734 20 27142 6a06 sched.o.before
24341 2734 20 27095 69d7 sched.o.after
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
fix delay accounting performance regression - those sched_clock()
calls are not needed.
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Get rid of 'sched_entity::fair_key'.
As a side effect, 'current' is not kept withing the tree for
SCHED_NORMAL/BATCH tasks anymore. This simplifies some parts of code
(e.g. entity_tick() and yield_task_fair()) and also somewhat optimizes
them (e.g. a single update_curr() now vs. dequeue/enqueue() before in
entity_tick()).
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
p->sched_class->set_curr_task() has to be called before
activate_task()/enqueue_task() in rt_mutex_setprio(),
sched_setschedule() and sched_move_task() in order to set up
'cfs_rq->curr'. The logic of enqueueing depends on whether a task to be
inserted is 'current' or not.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Fix a problem in the 'sched-group' patch for !CONFIG_FAIR_GROUP_SCHED.
description:
sched_setscheduler()
{
...
if (task_running()) p->sched_class->put_prev_entity();
[ this one sets up cfs_rq->curr to NULL ]
...
if (task_running) p->sched_class->set_curr_task();
[ and this one is a _NOP_ (empty) for !CONFIG_FAIR_GROUP_SCHED ]
As a result, the task continues to run with cfs_rq->curr == NULL... no
crashes (due to checks for !NULL in place) but e.g. update_curr()
effectively becomes a NOP... i.e. runtime statistics for this task is
not accounted untill it's rescheduled anew.
Signed-off-by: Dmitry Adamushko <dmitry.adamushko@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Add interface to control cpu bandwidth allocation to task-groups.
(not yet configurable, due to missing CONFIG_CONTAINERS)
Signed-off-by: Srivatsa Vaddagiri <vatsa@linux.vnet.ibm.com>
Signed-off-by: Dhaval Giani <dhaval@linux.vnet.ibm.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>