Re: [PATCH 1/2] powerpc/powernv: Treat an empty reboot string as default
On Mon, 2020-02-17 at 02:48:32 UTC, Oliver O'Halloran wrote: > Treat an empty reboot cmd string the same as a NULL string. This squashes a > spurious unsupported reboot message that sometimes gets out when using > xmon. > > Signed-off-by: Oliver O'Halloran Series applied to powerpc next, thanks. https://git.kernel.org/powerpc/c/16985f2d25095899685952296f128a71f0aff05c cheers
Re: [PATCH 1/2] powerpc/powernv: Treat an empty reboot string as default
On 24/02/2020 21:04, Segher Boessenkool wrote: > On Mon, Feb 24, 2020 at 01:32:28PM +1100, Alexey Kardashevskiy wrote: >> On 17/02/2020 13:48, Oliver O'Halloran wrote: >>> Treat an empty reboot cmd string the same as a NULL string. This squashes a >>> spurious unsupported reboot message that sometimes gets out when using >>> xmon. > >>> - if (!cmd) >>> + if (!cmd || !strlen(cmd)) >> >> nit: this does not matter here in practice but >> >> if (!cmd || cmd[0] == '\0') >> >> is faster (you do not care about the length anyway) and safer (@cmd can >> potentially be endless) ;) > > No it isn't, this compiles to identical machine code. (I tested with > GCC 9, and going back until 4.6 -- the generated code becomes > progressively worse (unrelated to this code, fwiw), but identical for > both cases all the time). oh cool, I did not think gcc is that smart. -- Alexey
Re: [PATCH 1/2] powerpc/powernv: Treat an empty reboot string as default
On Mon, Feb 24, 2020 at 01:32:28PM +1100, Alexey Kardashevskiy wrote: > On 17/02/2020 13:48, Oliver O'Halloran wrote: > > Treat an empty reboot cmd string the same as a NULL string. This squashes a > > spurious unsupported reboot message that sometimes gets out when using > > xmon. > > - if (!cmd) > > + if (!cmd || !strlen(cmd)) > > nit: this does not matter here in practice but > > if (!cmd || cmd[0] == '\0') > > is faster (you do not care about the length anyway) and safer (@cmd can > potentially be endless) ;) No it isn't, this compiles to identical machine code. (I tested with GCC 9, and going back until 4.6 -- the generated code becomes progressively worse (unrelated to this code, fwiw), but identical for both cases all the time). Segher
Re: [PATCH 1/2] powerpc/powernv: Treat an empty reboot string as default
On 17/2/20 1:48 pm, Oliver O'Halloran wrote: Treat an empty reboot cmd string the same as a NULL string. This squashes a spurious unsupported reboot message that sometimes gets out when using xmon. Signed-off-by: Oliver O'Halloran Pretty sure I've seen that spurious reboot message a few times and never thought to check why... this makes sense. Reviewed-by: Andrew Donnellan -- Andrew Donnellan OzLabs, ADL Canberra a...@linux.ibm.com IBM Australia Limited
Re: [PATCH 1/2] powerpc/powernv: Treat an empty reboot string as default
On 17/02/2020 13:48, Oliver O'Halloran wrote:
> Treat an empty reboot cmd string the same as a NULL string. This squashes a
> spurious unsupported reboot message that sometimes gets out when using
> xmon.
>
> Signed-off-by: Oliver O'Halloran
> ---
> arch/powerpc/platforms/powernv/setup.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/arch/powerpc/platforms/powernv/setup.c
> b/arch/powerpc/platforms/powernv/setup.c
> index 11fdae8..a8fe630 100644
> --- a/arch/powerpc/platforms/powernv/setup.c
> +++ b/arch/powerpc/platforms/powernv/setup.c
> @@ -229,7 +229,7 @@ static void __noreturn pnv_restart(char *cmd)
> pnv_prepare_going_down();
>
> do {
> - if (!cmd)
> + if (!cmd || !strlen(cmd))
nit: this does not matter here in practice but
if (!cmd || cmd[0] == '\0')
is faster (you do not care about the length anyway) and safer (@cmd can
potentially be endless) ;)
> rc = opal_cec_reboot();
> else if (strcmp(cmd, "full") == 0)
> rc = opal_cec_reboot2(OPAL_REBOOT_FULL_IPL, NULL);
>
--
Alexey
[PATCH 1/2] powerpc/powernv: Treat an empty reboot string as default
Treat an empty reboot cmd string the same as a NULL string. This squashes a
spurious unsupported reboot message that sometimes gets out when using
xmon.
Signed-off-by: Oliver O'Halloran
---
arch/powerpc/platforms/powernv/setup.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/powerpc/platforms/powernv/setup.c
b/arch/powerpc/platforms/powernv/setup.c
index 11fdae8..a8fe630 100644
--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -229,7 +229,7 @@ static void __noreturn pnv_restart(char *cmd)
pnv_prepare_going_down();
do {
- if (!cmd)
+ if (!cmd || !strlen(cmd))
rc = opal_cec_reboot();
else if (strcmp(cmd, "full") == 0)
rc = opal_cec_reboot2(OPAL_REBOOT_FULL_IPL, NULL);
--
2.9.5
