Sebastian Andrzej Siewior 3c118547f8 u64_stats: Disable preemption on 32bit UP+SMP PREEMPT_RT during updates. ... On PREEMPT_RT the seqcount_t for synchronisation is required on 32bit architectures even on UP because the softirq (and the threaded IRQ handler) can be preempted. With the seqcount_t for synchronisation, a reader with higher priority can preempt the writer and then spin endlessly in read_seqcount_begin() while the writer can't make progress. To avoid such a lock up on PREEMPT_RT the writer must disable preemption during the update. There is no need to disable interrupts because no writer is using this API in hard-IRQ context on PREEMPT_RT. Disable preemption on 32bit-RT within the u64_stats write section. Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by: David S. Miller <davem@davemloft.net>		2021-12-13 12:42:08 +00:00
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acpi
asm-generic
clocksource
crypto
drm
dt-bindings
keys
kunit
kvm
linux	u64_stats: Disable preemption on 32bit UP+SMP PREEMPT_RT during updates.	2021-12-13 12:42:08 +00:00
math-emu
media
memory
misc
net	bareudp: Move definition of struct bareudp_conf to bareudp.c	2021-12-13 12:34:09 +00:00
pcmcia
ras
rdma
scsi
soc	net: ocelot: add FDMA support	2021-12-10 20:56:58 -08:00
sound
target
trace
uapi	Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next	2021-12-10 15:56:13 -08:00
vdso
video
xen