[PATCH V2]: MIPS: fix and clean up

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* [PATCH V2]: MIPS: fix and clean up
@ 2021-09-08  9:08 Huang Pei
  2021-09-08  9:08 ` [PATCH 1/2] MIPS: rework local_t operation on MIPS64 Huang Pei
  2021-09-08  9:08 ` [PATCH 2/2] MIPS: retire "asm/llsc.h" Huang Pei
  0 siblings, 2 replies; 3+ messages in thread
From: Huang Pei @ 2021-09-08  9:08 UTC (permalink / raw)
  To: Thomas Bogendoerfer, ambrosehua
  Cc: Bibo Mao, linux-mips, linux-rt-users, Jiaxun Yang, Li Xuefeng,
	Yang Tiezhu, Gao Juxin, Huacai Chen, Jinyang He,
	Maciej W . Rozycki

[PATCH 1/2]: 

+. use daddu/dsubu for 64bit operation 

+. clean up 

[PATCH 2/2]:

+. retire "asm/llsc.h", following PATCH 1/2



^ permalink raw reply	[flat|nested] 3+ messages in thread

* [PATCH 1/2] MIPS: rework local_t operation on MIPS64
  2021-09-08  9:08 [PATCH V2]: MIPS: fix and clean up Huang Pei
@ 2021-09-08  9:08 ` Huang Pei
  2021-09-08  9:08 ` [PATCH 2/2] MIPS: retire "asm/llsc.h" Huang Pei
  1 sibling, 0 replies; 3+ messages in thread
From: Huang Pei @ 2021-09-08  9:08 UTC (permalink / raw)
  To: Thomas Bogendoerfer, ambrosehua
  Cc: Bibo Mao, linux-mips, linux-rt-users, Jiaxun Yang, Li Xuefeng,
	Yang Tiezhu, Gao Juxin, Huacai Chen, Jinyang He,
	Maciej W . Rozycki

+. Use daddu/dsubu for long int on MIPS64.

+. remove "asm/war.h" since R10000_LLSC_WAR became a config option

+. clean up, no function changed

Suggested-by:  "Maciej W. Rozycki" <macro@orcam.me.uk>
Signed-off-by: Huang Pei <huangpei@loongson.cn>
---
 arch/mips/include/asm/asm.h   | 18 +++++++++++
 arch/mips/include/asm/local.h | 60 ++++++++---------------------------
 2 files changed, 31 insertions(+), 47 deletions(-)

diff --git a/arch/mips/include/asm/asm.h b/arch/mips/include/asm/asm.h
index 2f8ce94ebaaf..f3302b13d3e0 100644
--- a/arch/mips/include/asm/asm.h
+++ b/arch/mips/include/asm/asm.h
@@ -19,6 +19,7 @@
 
 #include <asm/sgidefs.h>
 #include <asm/asm-eva.h>
+#include <asm/isa-rev.h>
 
 #ifndef __VDSO__
 /*
@@ -211,6 +212,8 @@ symbol		=	value
 #define LONG_SUB	sub
 #define LONG_SUBU	subu
 #define LONG_L		lw
+#define LONG_LL		ll
+#define LONG_SC		sc
 #define LONG_S		sw
 #define LONG_SP		swp
 #define LONG_SLL	sll
@@ -236,6 +239,8 @@ symbol		=	value
 #define LONG_SUB	dsub
 #define LONG_SUBU	dsubu
 #define LONG_L		ld
+#define LONG_LL		lld
+#define LONG_SC		scd
 #define LONG_S		sd
 #define LONG_SP		sdp
 #define LONG_SLL	dsll
@@ -320,6 +325,19 @@ symbol		=	value
 
 #define SSNOP		sll zero, zero, 1
 
+/*
+ * Using a branch-likely instruction to check the result of an sc instruction
+ * works around a bug present in R10000 CPUs prior to revision 3.0 that could
+ * cause ll-sc sequences to execute non-atomically.
+ */
+#ifdef CONFIG_WAR_R10000_LLSC
+# define SC_BEQZ	beqzl
+#elif MIPS_ISA_REV >= 6
+# define SC_BEQZ	beqzc
+#else
+# define SC_BEQZ	beqz
+#endif
+
 #ifdef CONFIG_SGI_IP28
 /* Inhibit speculative stores to volatile (e.g.DMA) or invalid addresses. */
 #include <asm/cacheops.h>
diff --git a/arch/mips/include/asm/local.h b/arch/mips/include/asm/local.h
index ecda7295ddcd..44b320583f04 100644
--- a/arch/mips/include/asm/local.h
+++ b/arch/mips/include/asm/local.h
@@ -7,7 +7,7 @@
 #include <linux/atomic.h>
 #include <asm/cmpxchg.h>
 #include <asm/compiler.h>
-#include <asm/war.h>
+#include <asm/asm.h>
 
 typedef struct
 {
@@ -31,34 +31,17 @@ static __inline__ long local_add_return(long i, local_t * l)
 {
 	unsigned long result;
 
-	if (kernel_uses_llsc && IS_ENABLED(CONFIG_WAR_R10000_LLSC)) {
-		unsigned long temp;
-
-		__asm__ __volatile__(
-		"	.set	push					\n"
-		"	.set	arch=r4000				\n"
-			__SYNC(full, loongson3_war) "			\n"
-		"1:"	__LL	"%1, %2		# local_add_return	\n"
-		"	addu	%0, %1, %3				\n"
-			__SC	"%0, %2					\n"
-		"	beqzl	%0, 1b					\n"
-		"	addu	%0, %1, %3				\n"
-		"	.set	pop					\n"
-		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
-		: "Ir" (i), "m" (l->a.counter)
-		: "memory");
-	} else if (kernel_uses_llsc) {
+	if (kernel_uses_llsc) {
 		unsigned long temp;
 
 		__asm__ __volatile__(
 		"	.set	push					\n"
 		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
-			__SYNC(full, loongson3_war) "			\n"
-		"1:"	__LL	"%1, %2		# local_add_return	\n"
-		"	addu	%0, %1, %3				\n"
-			__SC	"%0, %2					\n"
-		"	beqz	%0, 1b					\n"
-		"	addu	%0, %1, %3				\n"
+		"1:"	__stringify(LONG_LL)	"	%1, %2		\n"
+		"	"__stringify(LONG_ADDU)	"	%0, %1, %3	\n"
+		"	"__stringify(LONG_SC)	"	%0, %2		\n"
+		"	"__stringify(SC_BEQZ)	"	%0, 1b		\n"
+		"	"__stringify(LONG_ADDU)	"	%0, %1, %3	\n"
 		"	.set	pop					\n"
 		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
 		: "Ir" (i), "m" (l->a.counter)
@@ -80,34 +63,17 @@ static __inline__ long local_sub_return(long i, local_t * l)
 {
 	unsigned long result;
 
-	if (kernel_uses_llsc && IS_ENABLED(CONFIG_WAR_R10000_LLSC)) {
-		unsigned long temp;
-
-		__asm__ __volatile__(
-		"	.set	push					\n"
-		"	.set	arch=r4000				\n"
-			__SYNC(full, loongson3_war) "			\n"
-		"1:"	__LL	"%1, %2		# local_sub_return	\n"
-		"	subu	%0, %1, %3				\n"
-			__SC	"%0, %2					\n"
-		"	beqzl	%0, 1b					\n"
-		"	subu	%0, %1, %3				\n"
-		"	.set	pop					\n"
-		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
-		: "Ir" (i), "m" (l->a.counter)
-		: "memory");
-	} else if (kernel_uses_llsc) {
+	if (kernel_uses_llsc) {
 		unsigned long temp;
 
 		__asm__ __volatile__(
 		"	.set	push					\n"
 		"	.set	"MIPS_ISA_ARCH_LEVEL"			\n"
-			__SYNC(full, loongson3_war) "			\n"
-		"1:"	__LL	"%1, %2		# local_sub_return	\n"
-		"	subu	%0, %1, %3				\n"
-			__SC	"%0, %2					\n"
-		"	beqz	%0, 1b					\n"
-		"	subu	%0, %1, %3				\n"
+		"1:"	__stringify(LONG_LL)	"	%1, %2		\n"
+		"	"__stringify(LONG_SUBU)	"	%0, %1, %3	\n"
+		"	"__stringify(LONG_SC)	"	%0, %2		\n"
+		"	"__stringify(SC_BEQZ)	"	%0, 1b		\n"
+		"	"__stringify(LONG_SUBU)	"	%0, %1, %3	\n"
 		"	.set	pop					\n"
 		: "=&r" (result), "=&r" (temp), "=m" (l->a.counter)
 		: "Ir" (i), "m" (l->a.counter)
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

* [PATCH 2/2] MIPS: retire "asm/llsc.h"
  2021-09-08  9:08 [PATCH V2]: MIPS: fix and clean up Huang Pei
  2021-09-08  9:08 ` [PATCH 1/2] MIPS: rework local_t operation on MIPS64 Huang Pei
@ 2021-09-08  9:08 ` Huang Pei
  1 sibling, 0 replies; 3+ messages in thread
From: Huang Pei @ 2021-09-08  9:08 UTC (permalink / raw)
  To: Thomas Bogendoerfer, ambrosehua
  Cc: Bibo Mao, linux-mips, linux-rt-users, Jiaxun Yang, Li Xuefeng,
	Yang Tiezhu, Gao Juxin, Huacai Chen, Jinyang He,
	Maciej W . Rozycki

all that "asm/llsc.h" does is just to help inline asm, which can be
stringifyed from "asm/asm.h"

+. Since "asm/asm.h" has all we need, just stringify it and retire
   "asm/llsc.h"

+. remove unused header file

Inspired-by:   "Maciej W. Rozycki" <macro@orcam.me.uk>
Signed-off-by: Huang Pei <huangpei@loongson.cn>
---
 arch/mips/include/asm/asm.h      |  4 ++++
 arch/mips/include/asm/atomic.h   | 10 ++++------
 arch/mips/include/asm/bitops.h   | 24 +++++++++++-------------
 arch/mips/include/asm/cmpxchg.h  |  8 +++-----
 arch/mips/include/asm/kvm_host.h | 12 ++++++------
 5 files changed, 28 insertions(+), 30 deletions(-)

diff --git a/arch/mips/include/asm/asm.h b/arch/mips/include/asm/asm.h
index f3302b13d3e0..6ffdd4b5e1d0 100644
--- a/arch/mips/include/asm/asm.h
+++ b/arch/mips/include/asm/asm.h
@@ -222,6 +222,8 @@ symbol		=	value
 #define LONG_SRLV	srlv
 #define LONG_SRA	sra
 #define LONG_SRAV	srav
+#define LONG_INS	ins
+#define LONG_EXT	ext
 
 #ifdef __ASSEMBLY__
 #define LONG		.word
@@ -249,6 +251,8 @@ symbol		=	value
 #define LONG_SRLV	dsrlv
 #define LONG_SRA	dsra
 #define LONG_SRAV	dsrav
+#define LONG_INS	dins
+#define LONG_EXT	dext
 
 #ifdef __ASSEMBLY__
 #define LONG		.dword
diff --git a/arch/mips/include/asm/atomic.h b/arch/mips/include/asm/atomic.h
index 95e1f7f3597f..ebeda04cb0e3 100644
--- a/arch/mips/include/asm/atomic.h
+++ b/arch/mips/include/asm/atomic.h
@@ -20,9 +20,7 @@
 #include <asm/compiler.h>
 #include <asm/cpu-features.h>
 #include <asm/cmpxchg.h>
-#include <asm/llsc.h>
 #include <asm/sync.h>
-#include <asm/war.h>
 
 #define ATOMIC_OPS(pfx, type)						\
 static __always_inline type arch_##pfx##_read(const pfx##_t *v)		\
@@ -74,7 +72,7 @@ static __inline__ void arch_##pfx##_##op(type i, pfx##_t * v)		\
 	"1:	" #ll "	%0, %1		# " #pfx "_" #op "	\n"	\
 	"	" #asm_op " %0, %2				\n"	\
 	"	" #sc "	%0, %1					\n"	\
-	"\t" __SC_BEQZ "%0, 1b					\n"	\
+	"\t" __stringify(SC_BEQZ) "	%0, 1b			\n"	\
 	"	.set	pop					\n"	\
 	: "=&r" (temp), "+" GCC_OFF_SMALL_ASM() (v->counter)		\
 	: "Ir" (i) : __LLSC_CLOBBER);					\
@@ -104,7 +102,7 @@ arch_##pfx##_##op##_return_relaxed(type i, pfx##_t * v)			\
 	"1:	" #ll "	%1, %2		# " #pfx "_" #op "_return\n"	\
 	"	" #asm_op " %0, %1, %3				\n"	\
 	"	" #sc "	%0, %2					\n"	\
-	"\t" __SC_BEQZ "%0, 1b					\n"	\
+	"\t" __stringify(SC_BEQZ) "	%0, 1b			\n"	\
 	"	" #asm_op " %0, %1, %3				\n"	\
 	"	.set	pop					\n"	\
 	: "=&r" (result), "=&r" (temp),					\
@@ -137,7 +135,7 @@ arch_##pfx##_fetch_##op##_relaxed(type i, pfx##_t * v)			\
 	"1:	" #ll "	%1, %2		# " #pfx "_fetch_" #op "\n"	\
 	"	" #asm_op " %0, %1, %3				\n"	\
 	"	" #sc "	%0, %2					\n"	\
-	"\t" __SC_BEQZ "%0, 1b					\n"	\
+	"\t" __stringify(SC_BEQZ) "	%0, 1b			\n"	\
 	"	.set	pop					\n"	\
 	"	move	%0, %1					\n"	\
 	: "=&r" (result), "=&r" (temp),					\
@@ -237,7 +235,7 @@ static __inline__ int arch_##pfx##_sub_if_positive(type i, pfx##_t * v)	\
 	"	.set	push					\n"	\
 	"	.set	" MIPS_ISA_LEVEL "			\n"	\
 	"	" #sc "	%1, %2					\n"	\
-	"	" __SC_BEQZ "%1, 1b				\n"	\
+	"	" __stringify(SC_BEQZ) "	%1, 1b		\n"	\
 	"2:	" __SYNC(full, loongson3_war) "			\n"	\
 	"	.set	pop					\n"	\
 	: "=&r" (result), "=&r" (temp),					\
diff --git a/arch/mips/include/asm/bitops.h b/arch/mips/include/asm/bitops.h
index dc2a6234dd3c..3812082b8295 100644
--- a/arch/mips/include/asm/bitops.h
+++ b/arch/mips/include/asm/bitops.h
@@ -16,14 +16,12 @@
 #include <linux/bits.h>
 #include <linux/compiler.h>
 #include <linux/types.h>
+#include <asm/asm.h>
 #include <asm/barrier.h>
 #include <asm/byteorder.h>		/* sigh ... */
 #include <asm/compiler.h>
 #include <asm/cpu-features.h>
-#include <asm/isa-rev.h>
-#include <asm/llsc.h>
 #include <asm/sgidefs.h>
-#include <asm/war.h>
 
 #define __bit_op(mem, insn, inputs...) do {			\
 	unsigned long __temp;					\
@@ -32,10 +30,10 @@
 	"	.set		push			\n"	\
 	"	.set		" MIPS_ISA_LEVEL "	\n"	\
 	"	" __SYNC(full, loongson3_war) "		\n"	\
-	"1:	" __LL		"%0, %1			\n"	\
+	"1:	" __stringify(LONG_LL)	"	%0, %1	\n"	\
 	"	" insn		"			\n"	\
-	"	" __SC		"%0, %1			\n"	\
-	"	" __SC_BEQZ	"%0, 1b			\n"	\
+	"	" __stringify(LONG_SC)	"	%0, %1	\n"	\
+	"	" __stringify(SC_BEQZ)	"	%0, 1b	\n"	\
 	"	.set		pop			\n"	\
 	: "=&r"(__temp), "+" GCC_OFF_SMALL_ASM()(mem)		\
 	: inputs						\
@@ -49,10 +47,10 @@
 	"	.set		push			\n"	\
 	"	.set		" MIPS_ISA_LEVEL "	\n"	\
 	"	" __SYNC(full, loongson3_war) "		\n"	\
-	"1:	" __LL		ll_dst ", %2		\n"	\
+	"1:	" __stringify(LONG_LL) " "	ll_dst ", %2\n"	\
 	"	" insn		"			\n"	\
-	"	" __SC		"%1, %2			\n"	\
-	"	" __SC_BEQZ	"%1, 1b			\n"	\
+	"	" __stringify(LONG_SC)	"	%1, %2	\n"	\
+	"	" __stringify(SC_BEQZ)	"	%1, 1b	\n"	\
 	"	.set		pop			\n"	\
 	: "=&r"(__orig), "=&r"(__temp),				\
 	  "+" GCC_OFF_SMALL_ASM()(mem)				\
@@ -98,7 +96,7 @@ static inline void set_bit(unsigned long nr, volatile unsigned long *addr)
 	}
 
 	if ((MIPS_ISA_REV >= 2) && __builtin_constant_p(bit) && (bit >= 16)) {
-		__bit_op(*m, __INS "%0, %3, %2, 1", "i"(bit), "r"(~0));
+		__bit_op(*m, __stringify(LONG_INS) " %0, %3, %2, 1", "i"(bit), "r"(~0));
 		return;
 	}
 
@@ -126,7 +124,7 @@ static inline void clear_bit(unsigned long nr, volatile unsigned long *addr)
 	}
 
 	if ((MIPS_ISA_REV >= 2) && __builtin_constant_p(bit)) {
-		__bit_op(*m, __INS "%0, $0, %2, 1", "i"(bit));
+		__bit_op(*m, __stringify(LONG_INS) " %0, $0, %2, 1", "i"(bit));
 		return;
 	}
 
@@ -234,8 +232,8 @@ static inline int test_and_clear_bit(unsigned long nr,
 		res = __mips_test_and_clear_bit(nr, addr);
 	} else if ((MIPS_ISA_REV >= 2) && __builtin_constant_p(nr)) {
 		res = __test_bit_op(*m, "%1",
-				    __EXT "%0, %1, %3, 1;"
-				    __INS "%1, $0, %3, 1",
+				    __stringify(LONG_EXT) " %0, %1, %3, 1;"
+				    __stringify(LONG_INS) " %1, $0, %3, 1",
 				    "i"(bit));
 	} else {
 		orig = __test_bit_op(*m, "%0",
diff --git a/arch/mips/include/asm/cmpxchg.h b/arch/mips/include/asm/cmpxchg.h
index 0b983800f48b..fbfd5c5667e0 100644
--- a/arch/mips/include/asm/cmpxchg.h
+++ b/arch/mips/include/asm/cmpxchg.h
@@ -11,9 +11,7 @@
 #include <linux/bug.h>
 #include <linux/irqflags.h>
 #include <asm/compiler.h>
-#include <asm/llsc.h>
 #include <asm/sync.h>
-#include <asm/war.h>
 
 /*
  * These functions doesn't exist, so if they are called you'll either:
@@ -48,7 +46,7 @@ extern unsigned long __xchg_called_with_bad_pointer(void)
 		"	move	$1, %z3				\n"	\
 		"	.set	" MIPS_ISA_ARCH_LEVEL "		\n"	\
 		"	" st "	$1, %1				\n"	\
-		"\t" __SC_BEQZ	"$1, 1b				\n"	\
+		"\t" __stringify(SC_BEQZ)	"	$1, 1b	\n"	\
 		"	.set	pop				\n"	\
 		: "=&r" (__ret), "=" GCC_OFF_SMALL_ASM() (*m)		\
 		: GCC_OFF_SMALL_ASM() (*m), "Jr" (val)			\
@@ -127,7 +125,7 @@ unsigned long __xchg(volatile void *ptr, unsigned long x, int size)
 		"	move	$1, %z4				\n"	\
 		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"	\
 		"	" st "	$1, %1				\n"	\
-		"\t" __SC_BEQZ	"$1, 1b				\n"	\
+		"\t" __stringify(SC_BEQZ)	"	$1, 1b	\n"	\
 		"	.set	pop				\n"	\
 		"2:	" __SYNC(full, loongson3_war) "		\n"	\
 		: "=&r" (__ret), "=" GCC_OFF_SMALL_ASM() (*m)		\
@@ -279,7 +277,7 @@ static inline unsigned long __cmpxchg64(volatile void *ptr,
 	/* Attempt to store new at ptr */
 	"	scd	%L1, %2				\n"
 	/* If we failed, loop! */
-	"\t" __SC_BEQZ "%L1, 1b				\n"
+	"\t" __stringify(SC_BEQZ) "	%L1, 1b		\n"
 	"	.set	pop				\n"
 	"2:	" __SYNC(full, loongson3_war) "		\n"
 	: "=&r"(ret),
diff --git a/arch/mips/include/asm/kvm_host.h b/arch/mips/include/asm/kvm_host.h
index 696f6b009377..12202521dfbd 100644
--- a/arch/mips/include/asm/kvm_host.h
+++ b/arch/mips/include/asm/kvm_host.h
@@ -379,9 +379,9 @@ static inline void _kvm_atomic_set_c0_guest_reg(unsigned long *reg,
 		__asm__ __volatile__(
 		"	.set	push				\n"
 		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-		"	" __LL "%0, %1				\n"
+		"	"__stringify(LONG_LL)	" %0, %1	\n"
 		"	or	%0, %2				\n"
-		"	" __SC	"%0, %1				\n"
+		"	"__stringify(LONG_SC)	" %0, %1	\n"
 		"	.set	pop				\n"
 		: "=&r" (temp), "+m" (*reg)
 		: "r" (val));
@@ -396,9 +396,9 @@ static inline void _kvm_atomic_clear_c0_guest_reg(unsigned long *reg,
 		__asm__ __volatile__(
 		"	.set	push				\n"
 		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-		"	" __LL "%0, %1				\n"
+		"	"__stringify(LONG_LL)	" %0, %1	\n"
 		"	and	%0, %2				\n"
-		"	" __SC	"%0, %1				\n"
+		"	"__stringify(LONG_SC)	" %0, %1	\n"
 		"	.set	pop				\n"
 		: "=&r" (temp), "+m" (*reg)
 		: "r" (~val));
@@ -414,10 +414,10 @@ static inline void _kvm_atomic_change_c0_guest_reg(unsigned long *reg,
 		__asm__ __volatile__(
 		"	.set	push				\n"
 		"	.set	"MIPS_ISA_ARCH_LEVEL"		\n"
-		"	" __LL "%0, %1				\n"
+		"	"__stringify(LONG_LL) "	%0, %1		\n"
 		"	and	%0, %2				\n"
 		"	or	%0, %3				\n"
-		"	" __SC	"%0, %1				\n"
+		"	"__stringify(LONG_SC) " %0, %1		\n"
 		"	.set	pop				\n"
 		: "=&r" (temp), "+m" (*reg)
 		: "r" (~change), "r" (val & change));
-- 
2.25.1


^ permalink raw reply related	[flat|nested] 3+ messages in thread

end of thread, other threads:[~2021-09-08  9:09 UTC | newest]

Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-09-08  9:08 [PATCH V2]: MIPS: fix and clean up Huang Pei
2021-09-08  9:08 ` [PATCH 1/2] MIPS: rework local_t operation on MIPS64 Huang Pei
2021-09-08  9:08 ` [PATCH 2/2] MIPS: retire "asm/llsc.h" Huang Pei

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