Re: [PATCH 1/2] perf arm64: Handle __NR3264_ prefixed syscall number

[Alexander Kapshuk]

On Wed, May 24, 2023 at 6:19 AM Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> wrote:
>
>
>
> On 05/23/2023 08:31 PM, Alexander Kapshuk wrote:
> > On Tue, May 23, 2023 at 1:22 PM Tiezhu Yang <yangtiezhu@xxxxxxxxxxx> wrote:
> >>
> >> After commit 9854e7ad35fe ("perf arm64: Simplify mksyscalltbl"),
> >> in the generated syscall table file syscalls.c, there exist some
> >> __NR3264_ prefixed syscall numbers such as [__NR3264_ftruncate],
> >> it looks like not so good, just do some small filter operations
> >> to handle __NR3264_ prefixed syscall number as a digital number.
> >>
> >> Without this patch:
> >>
> >>   [__NR3264_ftruncate] = "ftruncate",
> >>
> >> With this patch:
> >>
> >>   [46] = "ftruncate",
> >>
> >> Signed-off-by: Tiezhu Yang <yangtiezhu@xxxxxxxxxxx>
> >> ---
> >>  tools/perf/arch/arm64/entry/syscalls/mksyscalltbl | 7 ++++---
> >>  1 file changed, 4 insertions(+), 3 deletions(-)
> >>
> >> diff --git a/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
> >> index 22cdf91..59ab7939 100755
> >> --- a/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
> >> +++ b/tools/perf/arch/arm64/entry/syscalls/mksyscalltbl
> >> @@ -39,7 +39,8 @@ create_table()
> >>         echo "};"
> >>  }
> >>
> >> -$gcc -E -dM -x c -I $incpath/include/uapi $input \
> >> -       |sed -ne 's/^#define __NR_//p' \
> >> -       |sort -t' ' -k2 -n             \
> >> +$gcc -E -dM -x c -I $incpath/include/uapi $input               \
> >> +       |awk '{if ($2~"__NR" && $3 !~"__NR3264_") {print}}'     \
> >> +       |sed -ne 's/^#define __NR_//p;s/^#define __NR3264_//p'  \
> >> +       |sort -t' ' -k2 -n                                      \
> >>         |create_table
> >> --
> >> 2.1.0
> >>
> >
> > As an aside, the awk + sed + sort parts of the command line may be
> > reduced to the following awk script, if desired:
> > awk '$2 ~ "__NR" && $3 !~ "__NR3264_" {
> >         sub("^#define __NR_", "")
> >         sub("^#define __NR3264_", "")
> >         print | "sort -k2 -n"
> > }'
> >
>
> Hi Alexander,
>
> Thanks, it seems more simple and works well as expected.
> Let us wait for more review comments before respin.
>
> If no any objections, I will send v2 with the following
> changes based on the current patch in the next week.
>
> -$gcc -E -dM -x c -I $incpath/include/uapi $input               \
> -       |awk '{if ($2~"__NR" && $3 !~"__NR3264_") {print}}'     \
> -       |sed -ne 's/^#define __NR_//p;s/^#define __NR3264_//p'  \
> -       |sort -t' ' -k2 -n                                      \
> +$gcc -E -dM -x c -I $incpath/include/uapi $input \
> +       |awk '$2 ~ "__NR" && $3 !~ "__NR3264_" {
> +               sub("^#define __NR_", "")
> +               sub("^#define __NR3264_", "")
> +               print | "sort -k2 -n"}' \
>          |create_table
>
> Thanks,
> Tiezhu
>

Hi Tiezhu,

Thanks for your prompt feedback.
It was merely a suggestion entirely subject to your discretion.

If no other patterns are anticipated to be processed by the sub
routines, they may be combined into a single sub routine like so:
awk '$2 ~ "__NR" && $3 !~ "__NR3264_" {
        sub("^#define __NR(3264)?_", "")
        print | "sort -k2 -n"
}'