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
..
bitops	wait_on_bit: add an acquire memory barrier	2022-08-26 09:30:25 -07:00
vdso	lib/vdso: Avoid highres update if clocksource is not VDSO capable	2020-02-17 20:12:17 +01:00
access_ok.h	uaccess: remove CONFIG_SET_FS	2022-02-25 09:36:06 +01:00
archrandom.h	random: handle archrandom with multiple longs	2022-07-25 13:26:14 +02:00
asm-offsets.h
asm-prototypes.h
atomic.h	locking/atomic: delete !ARCH_ATOMIC remnants	2021-05-26 13:20:52 +02:00
atomic64.h	locking/atomic: delete !ARCH_ATOMIC remnants	2021-05-26 13:20:52 +02:00
audit_change_attr.h
audit_dir_write.h
audit_read.h
audit_signal.h
audit_write.h
barrier.h	asm-generic: Add memory barrier dma_mb()	2022-06-23 18:34:58 +01:00
bitops.h	include: move find.h from asm_generic to linux	2022-01-15 08:47:31 -08:00
bitsperlong.h	lib: extend the scope of small_const_nbits() macro	2021-05-06 19:24:11 -07:00
bug.h	treewide: Drop WARN_ON_FUNCTION_MISMATCH	2022-09-26 10:13:14 -07:00
cache.h
cacheflush.h	asm-generic: instrument usercopy in cacheflush.h	2022-10-03 14:03:18 -07:00
checksum.h	unify generic instances of csum_partial_copy_nocheck()	2020-08-20 15:45:14 -04:00
cmpxchg-local.h	locking/atomic: cmpxchg: make generic a prefix	2021-05-26 13:20:50 +02:00
cmpxchg.h	locking/atomic: delete !ARCH_ATOMIC remnants	2021-05-26 13:20:52 +02:00
compat.h	asm-generic: compat: fix compat_arg_u64() and compat_arg_u64_dual()	2022-11-01 10:20:11 +11:00
current.h
delay.h
device.h
div64.h	ARM: 9117/1: asm-generic: div64: Remove always-true __div64_const32_is_OK()	2021-08-20 11:39:28 +01:00
dma-mapping.h
dma.h
early_ioremap.h	mm/early_ioremap.c: remove redundant early_ioremap_shutdown()	2021-09-08 11:50:24 -07:00
emergency-restart.h
error-injection.h	asm-generic/error-injection.h: fix a spelling mistake, and a coding style issue	2021-12-17 14:12:14 +01:00
exec.h
export.h	kbuild: link symbol CRCs at final link, removing CONFIG_MODULE_REL_CRCS	2022-05-24 16:33:20 +09:00
extable.h
fb.h
fixmap.h
flat.h
ftrace.h
futex.h	futex: Fix additional regressions	2021-12-11 23:31:51 +01:00
getorder.h	asm-generic: force inlining of get_order() to work around gcc10 poor decision	2020-12-15 22:46:15 -08:00
gpio.h	gpio: Avoid kernel.h inclusion where it's possible	2020-02-10 12:58:36 +01:00
hardirq.h	irqstat: Move declaration into asm-generic/hardirq.h	2020-11-23 10:31:06 +01:00
hugetlb.h	mm: change huge_ptep_clear_flush() to return the original pte	2022-05-13 16:48:55 -07:00
hw_irq.h
hyperv-tlfs.h	clocksource/drivers/hyperv: add data structure for reference TSC MSR	2022-11-03 15:50:28 +00:00
ide_iops.h
int-ll64.h
io.h	asm-generic/io.h: suppress endianness warnings for readq() and writeq()	2023-05-11 23:02:58 +09:00
ioctl.h
iomap.h	parisc: Declare pci_iounmap() parisc version only when CONFIG_PCI enabled	2021-09-19 10:36:09 -07:00
irq.h
irq_regs.h
irq_work.h
irqflags.h
Kbuild	xen: branch for v6.0-rc1	2022-08-04 15:10:55 -07:00
kdebug.h
kmap_size.h	mm/highmem: Provide and use CONFIG_DEBUG_KMAP_LOCAL	2020-11-24 14:42:08 +01:00
kprobes.h	treewide: Convert macro and uses of __section(foo) to __section("foo")	2020-10-25 14:51:49 -07:00
kvm_para.h
kvm_types.h	KVM: Move x86's version of struct kvm_mmu_memory_cache to common code	2020-07-09 13:29:42 -04:00
linkage.h
local.h
local64.h
logic_io.h	logic_io instance of iounmap() needs volatile on argument	2021-12-21 21:31:08 +01:00
mcs_spinlock.h
memory_model.h	mm: remove CONFIG_DISCONTIGMEM	2021-06-29 10:53:55 -07:00
mm_hooks.h	mm: remove arch_bprm_mm_init() hook	2020-01-23 10:41:16 -08:00
mmiowb.h	asm-generic/mmiowb: Allow mmiowb_set_pending() when preemptible()	2020-07-17 10:02:03 +01:00
mmiowb_types.h
mmu.h
mmu_context.h	asm-generic: add generic MMU versions of mmu context functions	2020-10-26 16:45:03 +01:00
module.h
module.lds.h	kbuild: preprocess module linker script	2020-09-25 00:36:41 +09:00
mshyperv.h	hyperv: simplify and rename generate_guest_id	2022-09-28 13:36:56 +00:00
msi.h	Generic interrupt and irqchips subsystem:	2020-12-15 15:03:31 -08:00
nommu_context.h	asm-generic: add generic MMU versions of mmu context functions	2020-10-26 16:45:03 +01:00
numa.h	numa: Move numa implementation to common code	2021-01-14 15:08:55 -08:00
page.h	c6x: remove architecture	2021-01-20 09:30:45 +01:00
param.h
parport.h
pci.h	asm-generic: Add new pci.h and use it	2022-07-22 17:34:57 -05:00
pci_iomap.h	PCI: Stub __pci_ioport_map() for arches that don't support it at all	2022-07-29 12:01:00 -05:00
percpu.h	asm-generic: percpu: avoid Wshadow warning	2020-10-26 23:54:48 +00:00
pgalloc.h	asm-generic: Prepare for riscv use of pud_alloc_one and pud_free	2022-01-19 17:54:08 -08:00
pgtable-nop4d.h	mm: rename p4d_page_vaddr to p4d_pgtable and make it return pud_t *	2021-07-08 11:48:22 -07:00
pgtable-nopmd.h	riscv/mm: fix two page table check related issues	2022-05-19 14:08:48 -07:00
pgtable-nopud.h	mm: rename p4d_page_vaddr to p4d_pgtable and make it return pud_t *	2021-07-08 11:48:22 -07:00
pgtable_uffd.h	userfaultfd: wp: add pmd_swp_*uffd_wp() helpers	2020-04-07 10:43:39 -07:00
preempt.h	sched/core: Initialize the idle task with preemption disabled	2021-05-12 13:01:45 +02:00
qrwlock.h	asm-generic changes for 5.19	2022-05-26 10:50:30 -07:00
qrwlock_types.h	locking/qrwlock: Change "queue rwlock" to "queued rwlock"	2022-05-11 16:27:04 +02:00
qspinlock.h	asm-generic: qspinlock: fix queued_spin_value_unlocked() implementation	2023-12-20 17:00:24 +01:00
qspinlock_types.h	locking/qspinlock: Do not include atomic.h from qspinlock_types.h	2020-07-29 16:14:19 +02:00
resource.h
rwonce.h	asm/rwonce: Don't pull <asm/barrier.h> into 'asm-generic/rwonce.h'	2020-07-21 10:50:36 +01:00
seccomp.h	seccomp: Use -1 marker for end of mode 1 syscall list	2020-07-10 16:01:52 -07:00
sections.h	asm-generic: sections: refactor memory_intersects	2022-08-28 14:02:45 -07:00
serial.h
set_memory.h
shmparam.h
signal.h	asm-generic: Remove empty #ifdef SA_RESTORER	2022-09-10 09:56:53 +02:00
simd.h
softirq_stack.h	asm-generic: Conditionally enable do_softirq_own_stack() via Kconfig.	2022-09-05 17:20:55 +02:00
spinlock.h	asm-generic: ticket-lock: New generic ticket-based spinlock	2022-05-11 11:49:38 -07:00
spinlock_types.h	asm-generic: ticket-lock: New generic ticket-based spinlock	2022-05-11 11:49:38 -07:00
statfs.h
string.h
switch_to.h
syscall.h	ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h	2022-03-10 13:35:08 -06:00
syscalls.h
timex.h
tlb.h	mm/khugepaged: fix GUP-fast interaction by sending IPI	2022-11-30 14:49:42 -08:00
tlbflush.h
topology.h	mm: replace CONFIG_NEED_MULTIPLE_NODES with CONFIG_NUMA	2021-06-29 10:53:55 -07:00
trace_clock.h
uaccess.h	uaccess: remove CONFIG_SET_FS	2022-02-25 09:36:06 +01:00
unaligned.h	asm-generic: make parameter types consistent in _unaligned_be48()	2022-09-11 21:55:12 -07:00
user.h
vermagic.h	arch: split MODULE_ARCH_VERMAGIC definitions out to <asm/vermagic.h>	2020-04-23 10:50:26 +09:00
vga.h
vmlinux.lds.h	arch: fix broken BuildID for arm64 and riscv	2023-02-25 11:25:42 +01:00
vtime.h
word-at-a-time.h	word-at-a-time: use the same return type for has_zero regardless of endianness	2023-08-11 12:08:11 +02:00
xor.h	lib/xor: make xor prototypes more friendly to compiler vectorization	2022-02-11 20:39:39 +11:00