Re: [PATCH v1 0/5] perf trace: Cleanup and remove unused bpf map

[Ian Rogers]

On Sun, Nov 20, 2022 at 11:52 PM Leo Yan <leo.yan@xxxxxxxxxx> wrote:
>
> The initial purpose of this series is to cleanup the unused bpf map
> 'syscalls' in the eBPF program augmented_raw_syscalls and perf trace
> tool.  The relality is perf trace tool initializes system call table
> based on map 'syscalls' and wrongly returns syscall pointer for
> non-existed system calls based on the previous initialization.
>
> So the patch set firstly addresses the issue for handling non-existed
> system calls, then it removes unused local variable and bpf map in
> augmented_raw_syscalls.c.
>
> Patch 01 is a minor refactoring to use macro to replace number, patch 02
> is to return error if a system call doesn't exist, especially when we
> cannot find corresponding trace point in sysfs node, patch 03 is to fix
> the issue that trace__syscall_info() returns a syscall pointer even the
> system call doesn't exist, the corrected result is to always return NULL
> pointer for non-existed system call.
>
> The last two patches remove the unused local variable and bpf map
> 'syscalls'.
>
> This patch set has been tested with mainline kernel on Arm64 Ampere
> Altra platform.
>
> Leo Yan (5):
>   perf trace: Use macro RAW_SYSCALL_ARGS_NUM to replace number
>   perf trace: Return error if a system call doesn't exist
>   perf trace: Handle failure when trace point folder is missed
>   perf augmented_raw_syscalls: Remove unused variable 'syscall'
>   perf trace: Remove unused bpf map 'syscalls'


Acked-by: Ian Rogers <irogers@xxxxxxxxxx>

Thanks,
Ian

>  tools/perf/builtin-trace.c                    | 131 +++---------------
>  .../examples/bpf/augmented_raw_syscalls.c     |  18 ---
>  2 files changed, 18 insertions(+), 131 deletions(-)
>
> --
> 2.34.1
>