Re: [PATCH 5/6 v3] syscalls: Remove start and number from syscall_get_arguments() args

[Max Filippov]

On Mon, Apr 1, 2019 at 6:45 AM Steven Rostedt <rostedt@xxxxxxxxxxx> wrote:
>
> From: "Steven Rostedt (Red Hat)" <rostedt@xxxxxxxxxxx>
>
> At Linux Plumbers, Andy Lutomirski approached me and pointed out that the
> function call syscall_get_arguments() implemented in x86 was horribly
> written and not optimized for the standard case of passing in 0 and 6 for
> the starting index and the number of system calls to get. When looking at
> all the users of this function, I discovered that all instances pass in only
> 0 and 6 for these arguments. Instead of having this function handle
> different cases that are never used, simply rewrite it to return the first 6
> arguments of a system call.
>
> This should help out the performance of tracing system calls by ptrace,
> ftrace and perf.

[...]

>  arch/xtensa/include/asm/syscall.h     | 16 ++----

For xtensa changes:
Acked-by: Max Filippov <jcmvbkbc@xxxxxxxxx>

-- 
Thanks.
-- Max