Miao Xie cb4ad1ffc7 sched: fair-group: fix a Div0 error of the fair group scheduler ...

When I echoed 0 into the "cpu.shares" file, a Div0 error occured.

We found it is caused by the following calling.

   sched_group_set_shares(tg, shares)
       set_se_shares(tg->se[i], shares/nr_cpu_ids)
           __set_se_shares(se, shares)
               div64_64((1ULL<<32), shares)

When the echoed value was less than the number of processores, the result of the
sentence "shares/nr_cpu_ids" was 0, and then the system called div64() to divide
the result, the Div0 error occured.

It is unnecessary that the shares value is divided by nr_cpu_ids, I think.
Because in the function  __update_group_shares_cpu() and init_tg_cfs_entry(),
the shares value isn't divided by nr_cpu_ids when setting shares of the sched
entity.

This patch fixes this bug. And echoing ULONG_MAX value into cpu.shares also
causes Div0 error, so we set a macro MAX_SHARES to limit the max value of
shares.

Signed-off-by: Miao Xie <miaox@cn.fujitsu.com>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

2008-05-05 23:56:18 +02:00

..

irq

genirq: reenable a nobody cared disabled irq when a new driver arrives

2008-05-02 13:40:34 +02:00

power

Merge branches 'release', 'acpica', 'bugzilla-10224', 'bugzilla-9772', 'bugzilla-9916', 'ec', 'eeepc', 'idle', 'misc', 'pm-legacy', 'sysfs-links-2.6.26', 'thermal', 'thinkpad' and 'video' into release

2008-04-30 13:58:00 -04:00

time

clocksource: allow read access to available/current_clocksource

2008-05-03 18:11:48 +02:00

.gitignore

Update kernel/.gitignore with new auto-generated files

2008-02-09 23:27:01 -08:00

acct.c

bsd_acct: using task_struct->tgid is not right in pid-namespaces

2008-03-24 19:22:20 -07:00

audit_tree.c

Introduce path_put()

2008-02-14 21:13:33 -08:00

audit.c

[patch 2/2] Use find_task_by_vpid in audit code

2008-04-28 06:28:30 -04:00

audit.h

[PATCH 1/2] audit: move extern declarations to audit.h

2008-04-28 06:28:04 -04:00

auditfilter.c

Merge branch 'audit.b50' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/audit-current

2008-04-29 11:41:22 -07:00

auditsc.c

[PATCH] new predicate - AUDIT_FILETYPE

2008-04-28 06:28:37 -04:00

backtracetest.c

x86: add a simple backtrace test module

2008-01-30 13:33:08 +01:00

bounds.c

Add kbuild.h that contains common definitions for kbuild users

2008-04-29 08:06:29 -07:00

capability.c

Add 64-bit capability support to the kernel

2008-02-05 09:44:20 -08:00

cgroup_debug.c

CGroup API files: move "releasable" to cgroup_debug subsystem

2008-04-29 08:06:09 -07:00

cgroup.c

mm: bdi: add separate writeback accounting capability

2008-04-30 08:29:50 -07:00

compat.c

ntp: support for TAI

2008-05-01 08:03:59 -07:00

configs.c

kernel: use non-racy method for proc entries creation

2008-04-29 08:06:22 -07:00

cpu.c

kernel: replace remaining __FUNCTION__ occurrences

2008-04-30 08:29:54 -07:00

cpuset.c

Cpuset hardwall flag: add a mem_hardwall flag to cpusets

2008-04-29 08:06:11 -07:00

delayacct.c

Add scaled time to taskstats based process accounting

2007-10-18 14:37:28 -07:00

dma.c

kernel: use non-racy method for proc entries creation

2008-04-29 08:06:22 -07:00

exec_domain.c

whitespace fixes: execution domains

2007-10-18 14:37:26 -07:00

exit.c

[PATCH] split linux/file.h

2008-05-01 13:08:16 -04:00

extable.c

module: Don't report discarded init pages as kernel text.

2008-01-29 17:13:18 +11:00

fork.c

[PATCH] split linux/file.h

2008-05-01 13:08:16 -04:00

futex_compat.c

futex_compat __user annotation

2008-03-30 14:18:41 -07:00

futex.c

Removal of FUTEX_FD

2008-05-05 08:18:45 -07:00

hrtimer.c

hrtimer: remove duplicate helper function

2008-05-03 18:11:48 +02:00

itimer.c

ITIMER_REAL: convert to use struct pid

2008-02-08 09:22:29 -08:00

kallsyms.c

kernel: use non-racy method for proc entries creation

2008-04-29 08:06:22 -07:00

Kconfig.hz

sched: high-res preemption tick

2008-01-25 21:08:29 +01:00

Kconfig.preempt

rcu: move PREEMPT_RCU config option back under PREEMPT

2008-03-10 18:01:20 -07:00

kexec.c

kexec: make extended crashkernel= syntax less confusing

2008-05-01 08:04:00 -07:00

kfifo.c

is_power_of_2: kernel/kfifo.c

2007-07-16 09:05:50 -07:00

kgdb.c

kgdb: fix signedness mixmatches, add statics, add declaration to header

2008-05-05 07:13:21 -05:00

kmod.c

[PATCH] split linux/file.h

2008-05-01 13:08:16 -04:00

kprobes.c

kprobes: add (un)register_jprobes for batch registration

2008-04-28 08:58:32 -07:00

ksysfs.c

Kobject: convert remaining kobject_unregister() to kobject_put()

2008-01-24 20:40:40 -08:00

kthread.c

Deprecate find_task_by_pid()

2008-04-30 08:29:48 -07:00

latencytop.c

kernel: use non-racy method for proc entries creation

2008-04-29 08:06:22 -07:00

lockdep_internals.h

[PATCH] lockdep: more chains

2006-12-07 08:39:43 -08:00

lockdep_proc.c

kernel: use non-racy method for proc entries creation

2008-04-29 08:06:22 -07:00

lockdep.c

Subject: lockdep: include all lock classes in all_lock_classes

2008-02-25 23:03:02 +01:00

Makefile

sysctl: allow embedded targets to disable sysctl_check.c

2008-04-29 08:06:22 -07:00

marker.c

make marker_debug static

2008-04-30 08:29:49 -07:00

module.c

Make forced module loading optional

2008-05-04 17:04:16 -07:00

mutex-debug.c

kernel: remove fastcall in kernel/*

2008-02-08 09:22:31 -08:00

mutex-debug.h

[PATCH] lockdep: better lock debugging

2006-07-03 15:27:01 -07:00

mutex.c

kernel: remove fastcall in kernel/*

2008-02-08 09:22:31 -08:00

mutex.h

[PATCH] lockdep: prove mutex locking correctness

2006-07-03 15:27:04 -07:00

notifier.c

ipc: re-enable msgmni automatic recomputing msgmni if set to negative

2008-04-29 08:06:13 -07:00

ns_cgroup.c

cgroups: kernel/ns_cgroup.c should #include <linux/nsproxy.h>

2008-04-29 08:06:07 -07:00

nsproxy.c

ipc: sysvsem: refuse clone(CLONE_SYSVSEM|CLONE_NEWIPC)

2008-04-29 08:06:14 -07:00

panic.c

Taint kernel after WARN_ON(condition)

2008-04-29 08:05:59 -07:00

params.c

Add new string functions strict_strto* and convert kernel params to use them

2008-02-08 09:22:41 -08:00

pid_namespace.c

pidns: make pid->level and pid_ns->level unsigned

2008-04-30 08:29:49 -07:00

pid.c

pids: introduce change_pid() helper

2008-04-30 08:29:48 -07:00

pm_qos_params.c

pm qos infrastructure and interface

2008-02-05 09:44:22 -08:00

posix-cpu-timers.c

remove div_long_long_rem

2008-05-01 08:03:58 -07:00

posix-timers.c

signals: join send_sigqueue() with send_group_sigqueue()

2008-04-30 08:29:36 -07:00

printk.c

printk: don't read beyond string arguments' terminating zero

2008-04-30 08:29:52 -07:00

profile.c

kernel: use non-racy method for proc entries creation

2008-04-29 08:06:22 -07:00

ptrace.c

make generic sys_ptrace unconditional

2008-05-01 10:21:54 -07:00

rcuclassic.c

Preempt-RCU: implementation

2008-01-25 21:08:24 +01:00

rcupdate.c

rcupdate: fix comment

2008-02-13 16:21:18 -08:00

rcupreempt_trace.c

Preempt-RCU: implementation

2008-01-25 21:08:24 +01:00

rcupreempt.c

generic: reduce stack pressure in sched_affinity

2008-04-19 19:44:59 +02:00

rcutorture.c

kernel: explicitly include required header files under kernel/

2008-04-29 08:06:04 -07:00

relay.c

Merge branch 'for-linus' of git://git.kernel.dk/linux-2.6-block

2008-04-29 08:18:03 -07:00

res_counter.c

memcgroup: add the max_usage member on the res_counter

2008-04-29 08:06:10 -07:00

resource.c

kernel: use non-racy method for proc entries creation

2008-04-29 08:06:22 -07:00

rtmutex_common.h

Don't operate with pid_t in rtmutex tester

2008-02-08 09:22:41 -08:00

rtmutex-debug.c

Don't operate with pid_t in rtmutex tester

2008-02-08 09:22:41 -08:00

rtmutex-debug.h

[PATCH] lockdep: better lock debugging

2006-07-03 15:27:01 -07:00

rtmutex-tester.c

Driver core: change sysdev classes to use dynamic kobject names

2008-01-24 20:40:40 -08:00

rtmutex.c

hrtimer: more hrtimer_init_sleeper() fallout.

2008-02-13 15:45:36 +01:00

rtmutex.h

[PATCH] lockdep: better lock debugging

2006-07-03 15:27:01 -07:00

rwsem.c

sched: mark rwsem functions as __sched for wchan/profiling

2007-12-18 15:21:13 +01:00

sched_debug.c

rename div64_64 to div64_u64

2008-05-01 08:03:58 -07:00

sched_fair.c

sched: fix debugging

2008-05-05 23:56:18 +02:00

sched_features.h

sched: /debug/sched_features

2008-04-19 19:45:00 +02:00

sched_idletask.c

sched: make rt_sched_class, idle_sched_class static

2008-05-05 23:56:17 +02:00

sched_rt.c

sched: fix RT task-wakeup logic

2008-05-05 23:56:18 +02:00

sched_stats.h

cpumask: use new cpus_scnprintf function

2008-04-19 19:44:59 +02:00

sched.c

sched: fair-group: fix a Div0 error of the fair group scheduler

2008-05-05 23:56:18 +02:00

seccomp.c

make seccomp zerocost in schedule

2007-07-16 09:05:50 -07:00

semaphore.c

Improve semaphore documentation

2008-04-17 10:43:01 -04:00

signal.c

signals: add set_restore_sigmask

2008-04-30 08:29:37 -07:00

softirq.c

Fix cpu hotplug problem in softirq code

2008-05-01 08:03:58 -07:00

softlockup.c

softlockup: fix task state setting

2008-02-29 18:46:53 +01:00

spinlock.c

spinlock: lockbreak cleanup

2008-01-30 13:31:20 +01:00

srcu.c

make srcu_readers_active() static

2008-02-06 10:41:02 -08:00

stacktrace.c

[PATCH] lockdep: stacktrace subsystem, core

2006-07-03 15:27:02 -07:00

stop_machine.c

Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/juhl/trivial

2008-04-21 16:36:46 -07:00

sys_ni.c

timerfd: new timerfd API

2008-02-05 09:44:07 -08:00

sys.c

pids: sys_getpgid: fix unsafe *pid usage, s/tasklist/rcu/

2008-04-30 08:29:49 -07:00

sysctl_check.c

constify tables in kernel/sysctl_check.c

2008-02-08 09:22:31 -08:00

sysctl.c

sysctl: add the ->permissions callback on the ctl_table_root

2008-04-29 08:06:23 -07:00

taskstats.c

Use find_task_by_vpid in taskstats

2008-04-30 08:29:48 -07:00

test_kprobes.c

kprobes: kretprobe user entry-handler

2008-02-06 10:41:11 -08:00

time.c

Make constants in kernel/timeconst.h fixed 64 bits

2008-05-02 16:18:42 -07:00

timeconst.pl

Make constants in kernel/timeconst.h fixed 64 bits

2008-05-02 16:18:42 -07:00

timer.c

debugobjects: add timer specific object debugging code

2008-04-30 08:29:53 -07:00

tsacct.c

Add scaled time to taskstats based process accounting

2007-10-18 14:37:28 -07:00

uid16.c

asmlinkage_protect replaces prevent_tail_call

2008-04-10 17:28:26 -07:00

user_namespace.c

eCryptfs: make key module subsystem respect namespaces

2008-04-29 08:06:07 -07:00

user.c

alloc_uid: cleanup

2008-04-30 08:29:53 -07:00

utsname_sysctl.c

Isolate the UTS namespace's domainname and hostname back

2007-11-29 09:24:53 -08:00

utsname.c

kernel: explicitly include required header files under kernel/

2008-04-29 08:06:04 -07:00

wait.c

kernel: remove fastcall in kernel/*

2008-02-08 09:22:31 -08:00

workqueue.c

workqueue: remove redundant function invocation

2008-05-01 08:04:02 -07:00