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switch-linux/include
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Peter Zijlstra b7e7ade34e sched/core: Fix remote wakeups 
Commit:

  b5179ac70d ("sched/fair: Prepare to fix fairness problems on migration")

... introduced a bug: Mike Galbraith found that it introduced a
performance regression, while Paul E. McKenney reported lost
wakeups and bisected it to this commit.

The reason is that I mis-read ttwu_queue() such that I assumed any
wakeup that got a remote queue must have had the task migrated.

Since this is not so; we need to transfer this information between
queueing the wakeup and actually doing the wakeup. Use a new
task_struct::sched_flag for this, we already write to
sched_contributes_to_load in the wakeup path so this is a hot and
modified cacheline.

Reported-by: Paul E. McKenney <paulmck@linux.vnet.ibm.com>
Reported-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Tested-by: Mike Galbraith <umgwanakikbuti@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Andrew Hunter <ahh@google.com>
Cc: Andy Lutomirski <luto@amacapital.net>
Cc: Ben Segall <bsegall@google.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Brian Gerst <brgerst@gmail.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Denys Vlasenko <dvlasenk@redhat.com>
Cc: Fenghua Yu <fenghua.yu@intel.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Matt Fleming <matt@codeblueprint.co.uk>
Cc: Morten Rasmussen <morten.rasmussen@arm.com>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Paul Turner <pjt@google.com>
Cc: Pavan Kondeti <pkondeti@codeaurora.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Quentin Casasnovas <quentin.casasnovas@oracle.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: byungchul.park@lge.com
Fixes: b5179ac70d ("sched/fair: Prepare to fix fairness problems on migration")
Link: http://lkml.kernel.org/r/20160523091907.GD15728@worktop.ger.corp.intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2016-05-25 08:35:18 +02:00
..
acpi device property: Avoid potential dereferences of invalid pointers 2016-04-27 23:40:02 +02:00
asm-generic sched/preempt: Fix preempt_count manipulations 2016-05-17 12:24:21 +02:00
clocksource
crypto
drm drm: Loongson-3 doesn't fully support wc memory 2016-04-22 10:24:11 +10:00
dt-bindings The clk changes for this release cycle are mostly dominated by 2016-03-23 06:06:45 -07:00
keys
kvm
linux sched/core: Fix remote wakeups 2016-05-25 08:35:18 +02:00
math-emu
media [media] media: vb2: Fix regression on poll() for RW mode 2016-04-25 10:21:23 -03:00
memory
misc
net udp_tunnel: Remove redundant udp_tunnel_gro_complete(). 2016-05-06 18:25:26 -04:00
pcmcia
ras
rdma IB/security: Restrict use of the write() interface 2016-04-28 12:03:16 -04:00
rxrpc
scsi Merge branch 'fixes-base' into fixes 2016-04-05 06:56:47 -04:00
soc IOMMU Updates for Linux v4.6 2016-03-22 11:57:43 -07:00
sound ALSA: hda - Update BCLK also at hotplug for i915 HSW/BDW 2016-04-26 10:11:11 +02:00
target target: add a new add_wwn_groups fabrics method 2016-03-30 20:06:44 -07:00
trace Merge branch 'for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/paulmck/linux-rcu into core/rcu 2016-04-27 16:57:36 +02:00
uapi Merge branch 'perf-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2016-05-16 14:08:43 -07:00
video gpu: ipu-v3: ipu-dmfc: Rename ipu_dmfc_init_channel to ipu_dmfc_config_wait4eot 2016-03-31 11:24:33 +02:00
xen xen: Fix page <-> pfn conversion on 32 bit systems 2016-04-06 11:18:17 +01:00
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