2023-10-04 15:14:54

by Clément Léger

Subject: [PATCH v2 1/8] riscv: remove unused functions in traps_misaligned.c

Replace macros by the only two function calls that are done from this
file, store_u8() and load_u8().

Signed-off-by: Clément Léger <[email protected]>
---
arch/riscv/kernel/traps_misaligned.c | 46 +++++-----------------------
1 file changed, 7 insertions(+), 39 deletions(-)

diff --git a/arch/riscv/kernel/traps_misaligned.c b/arch/riscv/kernel/traps_misaligned.c
index 378f5b151443..e7bfb33089c1 100644
--- a/arch/riscv/kernel/traps_misaligned.c
+++ b/arch/riscv/kernel/traps_misaligned.c
@@ -151,51 +151,19 @@
#define PRECISION_S 0
#define PRECISION_D 1

-#define DECLARE_UNPRIVILEGED_LOAD_FUNCTION(type, insn) \
-static inline type load_##type(const type *addr) \
-{ \
- type val; \
- asm (#insn " %0, %1" \
- : "=&r" (val) : "m" (*addr)); \
- return val; \
-}
+static inline u8 load_u8(const u8 *addr)
+{
+ u8 val;

-#define DECLARE_UNPRIVILEGED_STORE_FUNCTION(type, insn) \
-static inline void store_##type(type *addr, type val) \
-{ \
- asm volatile (#insn " %0, %1\n" \
- : : "r" (val), "m" (*addr)); \
-}
+ asm volatile("lbu %0, %1" : "=&r" (val) : "m" (*addr));

-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u8, lbu)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u16, lhu)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s8, lb)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s16, lh)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(s32, lw)
-DECLARE_UNPRIVILEGED_STORE_FUNCTION(u8, sb)
-DECLARE_UNPRIVILEGED_STORE_FUNCTION(u16, sh)
-DECLARE_UNPRIVILEGED_STORE_FUNCTION(u32, sw)
-#if defined(CONFIG_64BIT)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u32, lwu)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u64, ld)
-DECLARE_UNPRIVILEGED_STORE_FUNCTION(u64, sd)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(ulong, ld)
-#else
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(u32, lw)
-DECLARE_UNPRIVILEGED_LOAD_FUNCTION(ulong, lw)
-
-static inline u64 load_u64(const u64 *addr)
-{
- return load_u32((u32 *)addr)
- + ((u64)load_u32((u32 *)addr + 1) << 32);
+ return val;
}

-static inline void store_u64(u64 *addr, u64 val)
+static inline void store_u8(u8 *addr, u8 val)
{
- store_u32((u32 *)addr, val);
- store_u32((u32 *)addr + 1, val >> 32);
+ asm volatile ("sb %0, %1\n" : : "r" (val), "m" (*addr));
}
-#endif

static inline ulong get_insn(ulong mepc)
{
--
2.42.0

2023-10-04 16:52:07

by Björn Töpel

Subject: Re: [PATCH v2 1/8] riscv: remove unused functions in traps_misaligned.c

Clément Léger <[email protected]> writes:

> Replace macros by the only two function calls that are done from this
> file, store_u8() and load_u8().
>
> Signed-off-by: Clément Léger <[email protected]>
> ---
> arch/riscv/kernel/traps_misaligned.c | 46 +++++-----------------------
> 1 file changed, 7 insertions(+), 39 deletions(-)
>
> diff --git a/arch/riscv/kernel/traps_misaligned.c b/arch/riscv/kernel/traps_misaligned.c
> index 378f5b151443..e7bfb33089c1 100644
> --- a/arch/riscv/kernel/traps_misaligned.c
> +++ b/arch/riscv/kernel/traps_misaligned.c
> @@ -151,51 +151,19 @@
> #define PRECISION_S 0
> #define PRECISION_D 1
>
> -#define DECLARE_UNPRIVILEGED_LOAD_FUNCTION(type, insn) \
> -static inline type load_##type(const type *addr) \
> -{ \
> - type val; \
> - asm (#insn " %0, %1" \
> - : "=&r" (val) : "m" (*addr)); \
> - return val; \
> -}
> +static inline u8 load_u8(const u8 *addr)

Really a nit, and applies to the whole file: "static inline" in a .c
file is just useless.

> +{
> + u8 val;
>
> -#define DECLARE_UNPRIVILEGED_STORE_FUNCTION(type, insn) \
> -static inline void store_##type(type *addr, type val) \
> -{ \
> - asm volatile (#insn " %0, %1\n" \
> - : : "r" (val), "m" (*addr)); \
> -}
> + asm volatile("lbu %0, %1" : "=&r" (val) : "m" (*addr));

Why do you need early clobber here?


Björn

2023-10-09 13:03:11

by Clément Léger

Subject: Re: [PATCH v2 1/8] riscv: remove unused functions in traps_misaligned.c

On 04/10/2023 18:51, Björn Töpel wrote:
> Clément Léger <[email protected]> writes:
>
>> Replace macros by the only two function calls that are done from this
>> file, store_u8() and load_u8().
>>
>> Signed-off-by: Clément Léger <[email protected]>
>> ---
>> arch/riscv/kernel/traps_misaligned.c | 46 +++++-----------------------
>> 1 file changed, 7 insertions(+), 39 deletions(-)
>>
>> diff --git a/arch/riscv/kernel/traps_misaligned.c b/arch/riscv/kernel/traps_misaligned.c
>> index 378f5b151443..e7bfb33089c1 100644
>> --- a/arch/riscv/kernel/traps_misaligned.c
>> +++ b/arch/riscv/kernel/traps_misaligned.c
>> @@ -151,51 +151,19 @@
>> #define PRECISION_S 0
>> #define PRECISION_D 1
>>
>> -#define DECLARE_UNPRIVILEGED_LOAD_FUNCTION(type, insn) \
>> -static inline type load_##type(const type *addr) \
>> -{ \
>> - type val; \
>> - asm (#insn " %0, %1" \
>> - : "=&r" (val) : "m" (*addr)); \
>> - return val; \
>> -}
>> +static inline u8 load_u8(const u8 *addr)
>
> Really a nit, and applies to the whole file: "static inline" in a .c
> file is just useless.

Oh yes clearly, I should have fixed that while factorizing, I simply
kept them from the previous code.

>
>> +{
>> + u8 val;
>>
>> -#define DECLARE_UNPRIVILEGED_STORE_FUNCTION(type, insn) \
>> -static inline void store_##type(type *addr, type val) \
>> -{ \
>> - asm volatile (#insn " %0, %1\n" \
>> - : : "r" (val), "m" (*addr)); \
>> -}
>> + asm volatile("lbu %0, %1" : "=&r" (val) : "m" (*addr));
>
> Why do you need early clobber here?

Ditto, copy pasted from existing code but I don't think there is a need
for early clobber here.

Clément

>
>
> Björn