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authorLinus Torvalds <torvalds@linux-foundation.org>2022-05-31 14:10:54 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2022-05-31 14:10:54 -0700
commit35b51afd23c98e2f055ac563aca36173a12588b9 (patch)
treecadaa21cf4063afa7d2e420e97c1c8d186fb9795 /arch/riscv/include/asm/atomic.h
parente1cbc3b96a9974746b2a80c3a6c8a0f7eff7b1b5 (diff)
parent7699f7aacf3ebfee51c670b6f796b2797f0f7487 (diff)
Merge tag 'riscv-for-linus-5.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux
Pull RISC-V updates from Palmer Dabbelt: - Support for the Svpbmt extension, which allows memory attributes to be encoded in pages - Support for the Allwinner D1's implementation of page-based memory attributes - Support for running rv32 binaries on rv64 systems, via the compat subsystem - Support for kexec_file() - Support for the new generic ticket-based spinlocks, which allows us to also move to qrwlock. These should have already gone in through the asm-geneic tree as well - A handful of cleanups and fixes, include some larger ones around atomics and XIP * tag 'riscv-for-linus-5.19-mw0' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) RISC-V: Prepare dropping week attribute from arch_kexec_apply_relocations[_add] riscv: compat: Using seperated vdso_maps for compat_vdso_info RISC-V: Fix the XIP build RISC-V: Split out the XIP fixups into their own file RISC-V: ignore xipImage RISC-V: Avoid empty create_*_mapping definitions riscv: Don't output a bogus mmu-type on a no MMU kernel riscv: atomic: Add custom conditional atomic operation implementation riscv: atomic: Optimize dec_if_positive functions riscv: atomic: Cleanup unnecessary definition RISC-V: Load purgatory in kexec_file RISC-V: Add purgatory RISC-V: Support for kexec_file on panic RISC-V: Add kexec_file support RISC-V: use memcpy for kexec_file mode kexec_file: Fix kexec_file.c build error for riscv platform riscv: compat: Add COMPAT Kbuild skeletal support riscv: compat: ptrace: Add compat_arch_ptrace implement riscv: compat: signal: Add rt_frame implementation riscv: add memory-type errata for T-Head ...
Diffstat (limited to 'arch/riscv/include/asm/atomic.h')
-rw-r--r--arch/riscv/include/asm/atomic.h102
1 files changed, 92 insertions, 10 deletions
diff --git a/arch/riscv/include/asm/atomic.h b/arch/riscv/include/asm/atomic.h
index ac9bdf4fc404..0dfe9d857a76 100644
--- a/arch/riscv/include/asm/atomic.h
+++ b/arch/riscv/include/asm/atomic.h
@@ -310,47 +310,129 @@ ATOMIC_OPS()
#undef ATOMIC_OPS
#undef ATOMIC_OP
-static __always_inline int arch_atomic_sub_if_positive(atomic_t *v, int offset)
+static __always_inline bool arch_atomic_inc_unless_negative(atomic_t *v)
+{
+ int prev, rc;
+
+ __asm__ __volatile__ (
+ "0: lr.w %[p], %[c]\n"
+ " bltz %[p], 1f\n"
+ " addi %[rc], %[p], 1\n"
+ " sc.w.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev < 0);
+}
+
+#define arch_atomic_inc_unless_negative arch_atomic_inc_unless_negative
+
+static __always_inline bool arch_atomic_dec_unless_positive(atomic_t *v)
+{
+ int prev, rc;
+
+ __asm__ __volatile__ (
+ "0: lr.w %[p], %[c]\n"
+ " bgtz %[p], 1f\n"
+ " addi %[rc], %[p], -1\n"
+ " sc.w.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev > 0);
+}
+
+#define arch_atomic_dec_unless_positive arch_atomic_dec_unless_positive
+
+static __always_inline int arch_atomic_dec_if_positive(atomic_t *v)
{
int prev, rc;
__asm__ __volatile__ (
"0: lr.w %[p], %[c]\n"
- " sub %[rc], %[p], %[o]\n"
+ " addi %[rc], %[p], -1\n"
" bltz %[rc], 1f\n"
" sc.w.rl %[rc], %[rc], %[c]\n"
" bnez %[rc], 0b\n"
" fence rw, rw\n"
"1:\n"
: [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
- : [o]"r" (offset)
+ :
: "memory");
- return prev - offset;
+ return prev - 1;
}
-#define arch_atomic_dec_if_positive(v) arch_atomic_sub_if_positive(v, 1)
+#define arch_atomic_dec_if_positive arch_atomic_dec_if_positive
#ifndef CONFIG_GENERIC_ATOMIC64
-static __always_inline s64 arch_atomic64_sub_if_positive(atomic64_t *v, s64 offset)
+static __always_inline bool arch_atomic64_inc_unless_negative(atomic64_t *v)
+{
+ s64 prev;
+ long rc;
+
+ __asm__ __volatile__ (
+ "0: lr.d %[p], %[c]\n"
+ " bltz %[p], 1f\n"
+ " addi %[rc], %[p], 1\n"
+ " sc.d.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev < 0);
+}
+
+#define arch_atomic64_inc_unless_negative arch_atomic64_inc_unless_negative
+
+static __always_inline bool arch_atomic64_dec_unless_positive(atomic64_t *v)
+{
+ s64 prev;
+ long rc;
+
+ __asm__ __volatile__ (
+ "0: lr.d %[p], %[c]\n"
+ " bgtz %[p], 1f\n"
+ " addi %[rc], %[p], -1\n"
+ " sc.d.rl %[rc], %[rc], %[c]\n"
+ " bnez %[rc], 0b\n"
+ " fence rw, rw\n"
+ "1:\n"
+ : [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
+ :
+ : "memory");
+ return !(prev > 0);
+}
+
+#define arch_atomic64_dec_unless_positive arch_atomic64_dec_unless_positive
+
+static __always_inline s64 arch_atomic64_dec_if_positive(atomic64_t *v)
{
s64 prev;
long rc;
__asm__ __volatile__ (
"0: lr.d %[p], %[c]\n"
- " sub %[rc], %[p], %[o]\n"
+ " addi %[rc], %[p], -1\n"
" bltz %[rc], 1f\n"
" sc.d.rl %[rc], %[rc], %[c]\n"
" bnez %[rc], 0b\n"
" fence rw, rw\n"
"1:\n"
: [p]"=&r" (prev), [rc]"=&r" (rc), [c]"+A" (v->counter)
- : [o]"r" (offset)
+ :
: "memory");
- return prev - offset;
+ return prev - 1;
}
-#define arch_atomic64_dec_if_positive(v) arch_atomic64_sub_if_positive(v, 1)
+#define arch_atomic64_dec_if_positive arch_atomic64_dec_if_positive
#endif
#endif /* _ASM_RISCV_ATOMIC_H */