Vincent Guittot
f519a3f1c6
sched/core: Fix find_idlest_group() for fork ...
During fork, the utilization of a task is init once the rq has been
selected because the current utilization level of the rq is used to
set the utilization of the fork task. As the task's utilization is
still 0 at this step of the fork sequence, it doesn't make sense to
look for some spare capacity that can fit the task's utilization.
Furthermore, I can see perf regressions for the test:
hackbench -P -g 1
because the least loaded policy is always bypassed and tasks are not
spread during fork.
With this patch and the fix below, we are back to same performances as
for v4.8. The fix below is only a temporary one used for the test
until a smarter solution is found because we can't simply remove the
test which is useful for others benchmarks
| @@ -5708,13 +5708,6 @@ static int select_idle_cpu(struct task_struct *p, struct sched_domain *sd, int t
|
| avg_cost = this_sd->avg_scan_cost;
|
| - /*
| - * Due to large variance we need a large fuzz factor; hackbench in
| - * particularly is sensitive here.
| - */
| - if ((avg_idle / 512) < avg_cost)
| - return -1;
| -
| time = local_clock();
|
| for_each_cpu_wrap(cpu, sched_domain_span(sd), target, wrap) {
Tested-by: Matt Fleming <matt@codeblueprint.co.uk>
Signed-off-by: Vincent Guittot <vincent.guittot@linaro.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Matt Fleming <matt@codeblueprint.co.uk>
Acked-by: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: dietmar.eggemann@arm.com
Cc: kernellwp@gmail.com
Cc: umgwanakikbuti@gmail.com
Cc: yuyang.du@intel.comc
Link: http://lkml.kernel.org/r/1481216215-24651-2-git-send-email-vincent.guittot@linaro.org
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-12-11 13:10:56 +01:00
bpf: fix states equal logic for varlen access
2016-11-30 14:50:52 -05:00
config: android: enable CONFIG_SECCOMP
2016-10-11 15:06:32 -07:00
perf/core: Remove invalid warning from list_update_cgroup_even()t
2016-12-06 09:44:29 +01:00
gcov: add support for gcc version >= 6
2016-07-15 14:54:27 +09:00
genirq: Use irq type from irqdata instead of irqdesc
2016-11-08 15:15:19 +01:00
livepatch/module: make TAINT_LIVEPATCH module-specific
2016-08-26 14:42:08 +02:00
lockdep: Fix report formatting
2016-12-06 10:40:08 +01:00
PM / sleep: fix device reference leak in test_suspend
2016-11-02 05:10:04 +01:00
Revert "printk: make reading the kernel log flush pending lines"
2016-11-14 09:31:52 -08:00
This adds a new gcc plugin named "latent_entropy". It is designed to
2016-10-15 10:03:15 -07:00
sched/core: Fix find_idlest_group() for fork
2016-12-11 13:10:56 +01:00
sched/cputime: Simplify task_cputime()
2016-11-15 09:51:05 +01:00
ftrace: Add more checks for FTRACE_FL_DISABLED in processing ip records
2016-11-14 16:31:49 -05:00
Merge branch 'stable-4.9' of git://git.infradead.org/users/pcmoore/audit
2016-10-04 14:21:41 -07:00
Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
2016-07-29 17:54:17 -07:00
audit: cleanup prune_tree_thread
2016-04-04 09:46:47 -04:00
Merge branch 'stable-4.8' of git://git.infradead.org/users/pcmoore/audit
2016-09-01 15:55:56 -07:00
audit: add fields to exclude filter by reusing user filter
2016-06-27 11:01:00 -04:00
Merge branch 'stable-4.9' of git://git.infradead.org/users/pcmoore/audit
2016-10-04 14:21:41 -07:00
kernel: Add noaudit variant of ns_capable()
2016-06-06 20:16:18 +10:00
Merge branch 'for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
2016-10-14 12:18:50 -07:00
cgroup: Use lld instead of ld when printing pids controller events_limit
2016-06-21 15:03:36 -04:00
cpu/hotplug: Use distinct name for cpu_hotplug.dep_map
2016-10-16 11:09:32 +02:00
Merge branch 'for-4.9' of git://git.kernel.org/pub/scm/linux/kernel/git/tj/cgroup
2016-10-14 12:18:50 -07:00
cred: Reject inodes with invalid ids in set_create_file_as()
2016-06-30 18:05:09 -05:00
sched/autogroup: Do not use autogroup->tg in zombie threads
2016-11-22 12:33:43 +01:00
kthread: Make struct kthread kmalloc'ed
2016-12-08 14:36:18 +01:00
freezer, oom: check TIF_MEMDIE on the correct task
2016-07-28 16:07:41 -07:00
futex: Add some more function commentry
2016-09-05 17:20:18 +02:00
cred: simpler, 1D supplementary groups
2016-10-07 18:46:30 -07:00
hung_task: allow hung_task_panic when hung_task_warnings is 0
2016-10-11 15:06:33 -07:00
powerpc updates for 4.8 #2
2016-08-05 09:00:54 -04:00
kcov: add missing #include <linux/sched.h>
2016-12-07 17:10:00 -08:00
kexec: allow architectures to override boot mapping
2016-08-02 19:35:27 -04:00
kexec: add restriction on kexec_load() segment sizes
2016-08-02 19:35:31 -04:00
kexec: fix double-free when failing to relocate the purgatory
2016-09-01 17:52:01 -07:00
kprobes: include <asm/sections.h> instead of <asm-generic/sections.h>
2016-10-11 15:06:31 -07:00
kexec: add a kexec_crash_loaded() function
2016-08-02 19:35:30 -04:00
kthread: Don't abuse kthread_create_on_cpu() in __kthread_create_worker()
2016-12-08 14:36:20 +01:00
userns: Add per user namespace sysctls.
2016-08-08 13:18:58 -05:00
mm: fix cache mode of dax pmd mappings
2016-09-09 17:34:46 -07:00
Re-enable CONFIG_MODVERSIONS in a slightly weaker form
2016-11-29 16:01:30 -08:00
KEYS: Move the point of trust determination to __key_link()
2016-04-11 22:43:43 +01:00
padata: Convert to hotplug state machine
2016-09-19 21:44:30 +02:00
x86/panic: replace smp_send_stop() with kdump friendly version in panic path
2016-10-11 15:06:32 -07:00
remove lots of IS_ERR_VALUE abuses
2016-05-27 15:26:11 -07:00
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
profile: Convert to hotplug state machine
2016-07-15 10:41:42 +02:00
mm: replace access_process_vm() write parameter with gup_flags
2016-10-19 08:31:25 -07:00
relay: Use irq_work instead of plain timer for deferred wakeup
2016-10-11 15:06:32 -07:00
/proc/iomem: only expose physical resource addresses to privileged users
2016-04-14 12:56:09 -07:00
seccomp: Fix tracer exit notifications during fatal signals
2016-08-30 16:12:46 -07:00
x86/signal: Add SA_{X32,IA32}_ABI sa_flags
2016-09-14 21:28:11 +02:00
smp: Allocate smp_call_on_cpu() workqueue on stack too
2016-09-22 14:49:10 +02:00
kthread/smpboot: do not park in kthread_create_on_cpu()
2016-10-11 15:06:33 -07:00
softirq: Display IRQ_POLL for irq-poll statistics
2016-10-21 15:45:47 -06:00
Merge branch 'sched-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
2016-10-03 13:39:00 -07:00
prctl: make PR_SET_THP_DISABLE wait for mmap_sem killable
2016-05-23 17:04:14 -07:00
x86/pkeys: Fix pkeys build breakage for some non-x86 arches
2016-09-13 14:41:36 +02:00
sched/fair: Kill the unused 'sched_shares_window_ns' tunable
2016-10-20 08:44:57 +02:00
kernel/sysctl_binary.c: use generic UUID library
2016-05-20 17:58:30 -07:00
task_work: use READ_ONCE/lockless_dereference, avoid pi_lock if !task_works
2016-08-02 19:35:02 -04:00
taskstats: fix the length of cgroupstats_cmd_get_policy
2016-11-03 16:55:58 -04:00
torture: Convert torture_shutdown() to hrtimer
2016-08-22 10:01:49 -07:00
mntns: Add a limit on the number of mount namespaces.
2016-08-31 07:28:35 -05:00
cred: simpler, 1D supplementary groups
2016-10-07 18:46:30 -07:00
smp: Add function to execute a function synchronously on a CPU
2016-09-05 13:52:39 +02:00
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
Merge branch 'nsfs-ioctls' into HEAD
2016-09-22 20:00:36 -05:00
Revert "perf/x86/intel, watchdog: Switch NMI watchdog to ref cycles on x86"
2016-07-10 20:58:36 +02:00
kthread: rename probe_kthread_data() to kthread_probe_data()
2016-10-11 15:06:33 -07:00
f519a3f1c6