Athira Rajeev ef17515a8e selftests/powerpc/pmu/ebb: fix lost_exception_test hang with sched yield change ... commit 79104becf4 ("sched/fair: Forfeit vruntime on yield") changed yield_task_fair() to only bump the deadline when the entity is eligible (vruntime <= avg_vruntime). When the entity is ineligible the yield becomes a complete no-op from scheduling perspective. lost_exception_test calls sched_yield() 100,000 times per iteration to race the EBB exception delivery with a context switch to the eat_cpu companion process. After enough iterations the test process's vruntime races ahead of avg_vruntime (each eligible yield bumps vruntime to deadline, then advances deadline by one slice). Once ineligible, yield_task_fair() does nothing: so the scheduler won't pick the eat_cpu child. No context switch occurs, the PMAO race is never triggered, and ebb_count stays at 0 forever causing the test to hang until timeout. Fix by replacing sched_yield() with nanosleep(0, 1ns). nanosleep() goes through hrtimer_nanosleep() -> do_nanosleep(), which puts the task into TASK_INTERRUPTIBLE and removes it from the run queue entirely. This guarantees the scheduler picks the eat_cpu child, restoring the context-switch guarantee the test requires. The 1ns duration is enough to engage the hrtimer path while keeping the sleep effectively instantaneous; the same race window between PMU overflow and context switch is preserved. Reported-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com> Signed-off-by: Athira Rajeev <atrajeev@linux.ibm.com> Tested-by: Venkat Rao Bagalkote <venkat88@linux.ibm.com> Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com> Link: https://patch.msgid.link/20260903074036.63309-1-atrajeev@linux.ibm.com		2026-09-10 08:58:40 +05:30
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accounting
arch	- Remove the smp_locks alternatives machinery which was used to patch out lock	2026-08-18 18:11:25 -07:00
bootconfig	Bootconfig updates for v7.3:	2026-08-25 08:59:09 -07:00
bpf	perf tools updates for v7.3	2026-08-22 08:47:50 -07:00
build	perf build: Remove leftover feature tests for removed cxx and clang support	2026-08-12 06:17:49 -07:00
certs
cgroup
counter
crypto
debugging
dma
docs	doc tools: fix 'path' typos	2026-08-11 10:43:16 -06:00
firewire
firmware
gpio
hv
iio
include	Including fixes from Bluetooth, IPSec and Netfilter.	2026-08-27 13:53:43 -07:00
kvm/kvm_stat
laptop
leds
lib	More thermal control updates for 7.3-rc1	2026-08-26 14:21:30 -07:00
memory-model
mm	mm.git review status for master..mm-nonmm-stable	2026-08-23 08:07:11 -07:00
net	Including fixes from Bluetooth, IPSec and Netfilter.	2026-08-27 13:53:43 -07:00
objtool	Rust fixes for v7.3	2026-08-30 09:47:39 -07:00
pcmcia
perf	perf tools updates for v7.3	2026-08-22 08:47:50 -07:00
platform/x86/amd
power	linux-cpupower-7.3-rc1	2026-08-05 13:53:51 +02:00
rcu
sched
sched_ext	sched_ext: Merge branch 'for-7.3-arena-args' into for-7.3	2026-08-17 11:20:34 -10:00
scripts	perf tools updates for v7.3	2026-08-22 08:47:50 -07:00
sound
spi
testing	selftests/powerpc/pmu/ebb: fix lost_exception_test hang with sched yield change	2026-09-10 08:58:40 +05:30
thermal
time
tracing
unittests
usb
verification	verification/rvgen: Use .old instead of .bak for kunit backup files	2026-08-25 13:56:53 +02:00
virtio	tools/virtio: Fix control typo in trace agent comment	2026-08-19 06:38:48 -04:00
wmi
workqueue	workqueue: allocate attrs for all workqueues	2026-08-10 11:47:20 -10:00
writeback
Makefile