isa_ext_arr cannot be empty, as some of the extensions within it are
always built into the kernel.
Signed-off-by: Conor Dooley <[email protected]>
---
arch/riscv/kernel/cpu.c | 4 ----
1 file changed, 4 deletions(-)
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index 742bb42e7e86..01f7e5c62997 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -233,10 +233,6 @@ static void print_isa_ext(struct seq_file *f)
arr_sz = ARRAY_SIZE(isa_ext_arr) - 1;
- /* No extension support available */
- if (arr_sz <= 0)
- return;
-
for (i = 0; i <= arr_sz; i++) {
edata = &isa_ext_arr[i];
if (!__riscv_isa_extension_available(NULL, edata->isa_ext_id))
--
2.40.1
On Mon, Jun 26, 2023 at 12:19:40PM +0100, Conor Dooley wrote:
> isa_ext_arr cannot be empty, as some of the extensions within it are
> always built into the kernel.
This is only true since commit 07edc32779e3 ("RISC-V: always report
presence of extensions formerly part of the base ISA"), right? If
so, it might be nice to call that commit out in this commit message.
>
> Signed-off-by: Conor Dooley <[email protected]>
> ---
> arch/riscv/kernel/cpu.c | 4 ----
> 1 file changed, 4 deletions(-)
>
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index 742bb42e7e86..01f7e5c62997 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -233,10 +233,6 @@ static void print_isa_ext(struct seq_file *f)
>
> arr_sz = ARRAY_SIZE(isa_ext_arr) - 1;
>
> - /* No extension support available */
> - if (arr_sz <= 0)
> - return;
> -
> for (i = 0; i <= arr_sz; i++) {
> edata = &isa_ext_arr[i];
> if (!__riscv_isa_extension_available(NULL, edata->isa_ext_id))
> --
> 2.40.1
>
Otherwise,
Reviewed-by: Andrew Jones <[email protected]>
Thanks,
drew
On Mon, Jun 26, 2023 at 05:19:08PM +0200, Andrew Jones wrote:
> On Mon, Jun 26, 2023 at 12:19:40PM +0100, Conor Dooley wrote:
> > isa_ext_arr cannot be empty, as some of the extensions within it are
> > always built into the kernel.
>
> This is only true since commit 07edc32779e3 ("RISC-V: always report
> presence of extensions formerly part of the base ISA"), right? If
> so, it might be nice to call that commit out in this commit message.
Per my last mail, where I commented on the origins of some of this code,
there were no multi-letter extensions when this code was first added.
When the first multi-letter ones did get added, it was Sscofpmf - that
doesn't have a Kconfig symbol to disable it, so I think this has been
redundant for a long time.
Apart from the ones I recently added, there's a fair few others that
are not gated & should always be present.
It's probably not clear from the comment, but this check is for whether
the kernel supports extensions, not whether the system it is running on
does. I guess I should expand on that in my commit message.
Thanks,
Conor.
> > Signed-off-by: Conor Dooley <[email protected]>
> > ---
> > arch/riscv/kernel/cpu.c | 4 ----
> > 1 file changed, 4 deletions(-)
> >
> > diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> > index 742bb42e7e86..01f7e5c62997 100644
> > --- a/arch/riscv/kernel/cpu.c
> > +++ b/arch/riscv/kernel/cpu.c
> > @@ -233,10 +233,6 @@ static void print_isa_ext(struct seq_file *f)
> >
> > arr_sz = ARRAY_SIZE(isa_ext_arr) - 1;
> >
> > - /* No extension support available */
> > - if (arr_sz <= 0)
> > - return;
> > -
> > for (i = 0; i <= arr_sz; i++) {
> > edata = &isa_ext_arr[i];
> > if (!__riscv_isa_extension_available(NULL, edata->isa_ext_id))
> > --
> > 2.40.1
> >
>
> Otherwise,
>
> Reviewed-by: Andrew Jones <[email protected]>
>
> Thanks,
> drew
On Mon, Jun 26, 2023 at 05:08:28PM +0100, Conor Dooley wrote:
> On Mon, Jun 26, 2023 at 05:19:08PM +0200, Andrew Jones wrote:
> > On Mon, Jun 26, 2023 at 12:19:40PM +0100, Conor Dooley wrote:
> > > isa_ext_arr cannot be empty, as some of the extensions within it are
> > > always built into the kernel.
> >
> > This is only true since commit 07edc32779e3 ("RISC-V: always report
> > presence of extensions formerly part of the base ISA"), right? If
> > so, it might be nice to call that commit out in this commit message.
>
> Per my last mail, where I commented on the origins of some of this code,
> there were no multi-letter extensions when this code was first added.
> When the first multi-letter ones did get added, it was Sscofpmf - that
> doesn't have a Kconfig symbol to disable it, so I think this has been
> redundant for a long time.
>
> Apart from the ones I recently added, there's a fair few others that
> are not gated & should always be present.
> It's probably not clear from the comment, but this check is for whether
> the kernel supports extensions, not whether the system it is running on
> does. I guess I should expand on that in my commit message.
That part I understood, but I was thinking it'd be nice to call out when
the first extension was added which cannot be disabled by a config to
provide extra evidence that it's safe to remove the check.
Thanks,
drew