Linus Torvalds f7ce765744 asm-generic: qspinlock: fix queued_spin_value_unlocked() implementation ... [ Upstream commit 125b0bb95d ] We really don't want to do atomic_read() or anything like that, since we already have the value, not the lock. The whole point of this is that we've loaded the lock from memory, and we want to check whether the value we loaded was a locked one or not. The main use of this is the lockref code, which loads both the lock and the reference count in one atomic operation, and then works on that combined value. With the atomic_read(), the compiler would pointlessly spill the value to the stack, in order to then be able to read it back "atomically". This is the qspinlock version of commit c6f4a90022 ("asm-generic: ticket-lock: Optimize arch_spin_value_unlocked()") which fixed this same bug for ticket locks. Cc: Guo Ren <guoren@kernel.org> Cc: Ingo Molnar <mingo@kernel.org> Cc: Waiman Long <longman@redhat.com> Link: https://lore.kernel.org/all/CAHk-=whNRv0v6kQiV5QO6DJhjH4KEL36vWQ6Re8Csrnh4zbRkQ@mail.gmail.com/ Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2023-12-20 17:00:24 +01:00
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acpi
asm-generic	asm-generic: qspinlock: fix queued_spin_value_unlocked() implementation	2023-12-20 17:00:24 +01:00
clocksource
crypto
drm
dt-bindings
keys
kunit	kunit: add macro to allow conditionally exposing static symbols to tests	2023-11-20 11:52:08 +01:00
kvm
linux	cred: switch to using atomic_long_t	2023-12-20 17:00:20 +01:00
math-emu
media
memory
misc
net	net: ipv6: support reporting otherwise unknown prefix flags in RTM_NEWPREFIX	2023-12-20 17:00:15 +01:00
pcmcia
ras
rdma	RDMA/core: Fix umem iterator when PAGE_SIZE is greater then HCA pgsz	2023-12-13 18:39:15 +01:00
rv
scsi	scsi: sd: Fix system start for ATA devices	2023-12-08 08:51:14 +01:00
soc
sound	ASoC: SOF: Pass PCI SSID to machine driver	2023-11-28 17:06:58 +00:00
target
trace
uapi	netfilter: nft_exthdr: add boolean DCCP option matching	2023-12-13 18:39:10 +01:00
ufs
vdso
video
xen	xen: simplify evtchn_do_upcall() call maze	2023-12-08 08:51:20 +01:00