Files
android/arch/alpha/lib/dec_and_lock.c
T
threeeye bc1d038eac REVVL 6 Pro kernel bring-up: full working tree snapshot (2026-09-12)
Squashed backup commit (no shallow-clone history issues) of
xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2 branch, upstream
commit 9eece662e) plus all fixes applied to get everpal_defconfig building
clean against a modern (GCC 15.2.0) toolchain -- see the previous commit
message on the lineage-23.2 branch (also in this repo history is not
available here since this is a squashed snapshot; full incremental history
lives in the local DL380 checkout and the upstream GitHub remote).

Upstream: https://github.com/xiaomi-mt6833-dev/kernel_xiaomi_mt6833 (lineage-23.2)
2026-09-12 13:36:46 +00:00

45 lines
910 B
C

// SPDX-License-Identifier: GPL-2.0
/*
* arch/alpha/lib/dec_and_lock.c
*
* ll/sc version of atomic_dec_and_lock()
*
*/
#include <linux/spinlock.h>
#include <linux/atomic.h>
#include <linux/export.h>
asm (".text \n\
.global _atomic_dec_and_lock \n\
.ent _atomic_dec_and_lock \n\
.align 4 \n\
_atomic_dec_and_lock: \n\
.prologue 0 \n\
1: ldl_l $1, 0($16) \n\
subl $1, 1, $1 \n\
beq $1, 2f \n\
stl_c $1, 0($16) \n\
beq $1, 4f \n\
mb \n\
clr $0 \n\
ret \n\
2: br $29, 3f \n\
3: ldgp $29, 0($29) \n\
br $atomic_dec_and_lock_1..ng \n\
.subsection 2 \n\
4: br 1b \n\
.previous \n\
.end _atomic_dec_and_lock");
static int __used atomic_dec_and_lock_1(atomic_t *atomic, spinlock_t *lock)
{
/* Slow path */
spin_lock(lock);
if (atomic_dec_and_test(atomic))
return 1;
spin_unlock(lock);
return 0;
}
EXPORT_SYMBOL(_atomic_dec_and_lock);