This reduces the number of variables and makes the code easier to parse.

Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
---

Changes in v2:
 - Further simplify patch_insn_set()/patch_insn_write() loop conditions
 - Use min() instead of min_t() since both sides are unsigned long

 arch/riscv/kernel/patch.c | 37 +++++++++++++++++++++----------------
 1 file changed, 21 insertions(+), 16 deletions(-)

diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
index 9a1bce1adf5a..0d1700d1934c 100644
--- a/arch/riscv/kernel/patch.c
+++ b/arch/riscv/kernel/patch.c
@@ -155,22 +155,24 @@ NOKPROBE_SYMBOL(__patch_insn_write);
 
 static int patch_insn_set(void *addr, u8 c, size_t len)
 {
-	size_t patched = 0;
 	size_t size;
-	int ret = 0;
+	int ret;
 
 	/*
 	 * __patch_insn_set() can only work on 2 pages at a time so call it in a
 	 * loop with len <= 2 * PAGE_SIZE.
 	 */
-	while (patched < len && !ret) {
-		size = min_t(size_t, PAGE_SIZE * 2 - offset_in_page(addr + patched), len - patched);
-		ret = __patch_insn_set(addr + patched, c, size);
-
-		patched += size;
+	while (len) {
+		size = min(len, PAGE_SIZE * 2 - offset_in_page(addr));
+		ret = __patch_insn_set(addr, c, size);
+		if (ret)
+			return ret;
+
+		addr += size;
+		len -= size;
 	}
 
-	return ret;
+	return 0;
 }
 NOKPROBE_SYMBOL(patch_insn_set);
 
@@ -190,22 +192,25 @@ NOKPROBE_SYMBOL(patch_text_set_nosync);
 
 int patch_insn_write(void *addr, const void *insn, size_t len)
 {
-	size_t patched = 0;
 	size_t size;
-	int ret = 0;
+	int ret;
 
 	/*
 	 * Copy the instructions to the destination address, two pages at a time
 	 * because __patch_insn_write() can only handle len <= 2 * PAGE_SIZE.
 	 */
-	while (patched < len && !ret) {
-		size = min_t(size_t, PAGE_SIZE * 2 - offset_in_page(addr + patched), len - patched);
-		ret = __patch_insn_write(addr + patched, insn + patched, size);
-
-		patched += size;
+	while (len) {
+		size = min(len, PAGE_SIZE * 2 - offset_in_page(addr));
+		ret = __patch_insn_write(addr, insn, size);
+		if (ret)
+			return ret;
+
+		addr += size;
+		insn += size;
+		len -= size;
 	}
 
-	return ret;
+	return 0;
 }
 NOKPROBE_SYMBOL(patch_insn_write);
 
-- 
2.43.1

On Wed, Mar 27, 2024 at 09:04:43AM -0700, Samuel Holland wrote:
> This reduces the number of variables and makes the code easier to parse.
> 
> Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
> ---
> 
> Changes in v2:
>  - Further simplify patch_insn_set()/patch_insn_write() loop conditions
>  - Use min() instead of min_t() since both sides are unsigned long
> 
>  arch/riscv/kernel/patch.c | 37 +++++++++++++++++++++----------------
>  1 file changed, 21 insertions(+), 16 deletions(-)
> 
> diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
> index 9a1bce1adf5a..0d1700d1934c 100644
> --- a/arch/riscv/kernel/patch.c
> +++ b/arch/riscv/kernel/patch.c
> @@ -155,22 +155,24 @@ NOKPROBE_SYMBOL(__patch_insn_write);
>  
>  static int patch_insn_set(void *addr, u8 c, size_t len)
>  {
> -	size_t patched = 0;
>  	size_t size;
> -	int ret = 0;
>  
>  	/*
>  	 * __patch_insn_set() can only work on 2 pages at a time so call it in a
>  	 * loop with len <= 2 * PAGE_SIZE.
>  	 */
> -	while (patched < len && !ret) {
> -		size = min_t(size_t, PAGE_SIZE * 2 - offset_in_page(addr + patched), len - patched);
> -		ret = __patch_insn_set(addr + patched, c, size);
> -
> -		patched += size;
>  	}
>  
> -	return ret;
>  }

Weren't these actively wrong before, if a non-ultimate
__patch_insn_set() failed we'd just ignore the error?

Reviewed-by: Conor Dooley <conor.dooley@microchip.com>

Thanks,
Conor.

On Wed, Apr 24, 2024 at 11:44:17AM +0100, Conor Dooley wrote:
> On Wed, Mar 27, 2024 at 09:04:43AM -0700, Samuel Holland wrote:
> > This reduces the number of variables and makes the code easier to parse.
> > 
> > Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
> > ---
> > 
> > Changes in v2:
> >  - Further simplify patch_insn_set()/patch_insn_write() loop conditions
> >  - Use min() instead of min_t() since both sides are unsigned long
> > 
> >  arch/riscv/kernel/patch.c | 37 +++++++++++++++++++++----------------
> >  1 file changed, 21 insertions(+), 16 deletions(-)
> > 
> > diff --git a/arch/riscv/kernel/patch.c b/arch/riscv/kernel/patch.c
> > index 9a1bce1adf5a..0d1700d1934c 100644
> > --- a/arch/riscv/kernel/patch.c
> > +++ b/arch/riscv/kernel/patch.c
> > @@ -155,22 +155,24 @@ NOKPROBE_SYMBOL(__patch_insn_write);
> >  
> >  static int patch_insn_set(void *addr, u8 c, size_t len)
> >  {
> > -	size_t patched = 0;
> >  	size_t size;
> > -	int ret = 0;
> >  
> >  	/*
> >  	 * __patch_insn_set() can only work on 2 pages at a time so call it in a
> >  	 * loop with len <= 2 * PAGE_SIZE.
> >  	 */
> > -	while (patched < len && !ret) {
> > -		size = min_t(size_t, PAGE_SIZE * 2 - offset_in_page(addr + patched), len - patched);
> > -		ret = __patch_insn_set(addr + patched, c, size);
> > -
> > -		patched += size;
> >  	}
> >  
> > -	return ret;
> >  }
> 
> Weren't these actively wrong before, if a non-ultimate
> __patch_insn_set() failed we'd just ignore the error?

nvm, failure to read on my part..

Samuel Holland <samuel.holland@sifive.com> writes:

> This reduces the number of variables and makes the code easier to parse.
>
> Signed-off-by: Samuel Holland <samuel.holland@sifive.com>
> ---
>
> Changes in v2:
>  - Further simplify patch_insn_set()/patch_insn_write() loop conditions
>  - Use min() instead of min_t() since both sides are unsigned long

Thanks for addressing the changes! Nice cleanup!

Reviewed-by: Björn Töpel <bjorn@rivosinc.com>