Re: [RESEND PATCH v4 5/5] sysctl: delete six_hundred_forty_kb to save 4 bytes

From: Joel Granados
Date: Wed Oct 09 2024 - 04:59:20 EST


Hey

I have the last version in line for review this week. I'll ignore this
"resend" as it is the same as the previous email.
FYI: I have moved to joel.granados@xxxxxxxxxx. please send all sysctl
related stuff there, I might miss it if it lands here.

Best


On Tue, Oct 08, 2024 at 11:17:00PM +0800, Wen Yang wrote:
> By directly encoding specific numbers into the min/max field,
> unnecessary global variable six_hundred_forty_kb can be removed,
> saving 4 bytes
>
> Signed-off-by: Wen Yang <wen.yang@xxxxxxxxx>
> Cc: Luis Chamberlain <mcgrof@xxxxxxxxxx>
> Cc: Kees Cook <keescook@xxxxxxxxxxxx>
> Cc: Joel Granados <j.granados@xxxxxxxxxxx>
> Cc: Eric W. Biederman <ebiederm@xxxxxxxxxxxx>
> Cc: Christian Brauner <brauner@xxxxxxxxxx>
> Cc: Dave Young <dyoung@xxxxxxxxxx>
> Cc: linux-kernel@xxxxxxxxxxxxxxx
> ---
> kernel/sysctl.c | 13 +++----------
> 1 file changed, 3 insertions(+), 10 deletions(-)
>
> diff --git a/kernel/sysctl.c b/kernel/sysctl.c
> index 05197d46007d..c8460b5e0605 100644
> --- a/kernel/sysctl.c
> +++ b/kernel/sysctl.c
> @@ -90,13 +90,6 @@ EXPORT_SYMBOL_GPL(sysctl_long_vals);
>
> #if defined(CONFIG_SYSCTL)
>
> -/* Constants used for minimum and maximum */
> -
> -#ifdef CONFIG_PERF_EVENTS
> -static const int six_hundred_forty_kb = 640 * 1024;
> -#endif
> -
> -
> static const int ngroups_max = NGROUPS_MAX;
> static const int cap_last_cap = CAP_LAST_CAP;
>
> @@ -1964,10 +1957,10 @@ static struct ctl_table kern_table[] = {
> .procname = "perf_event_max_stack",
> .data = &sysctl_perf_event_max_stack,
> .maxlen = sizeof(sysctl_perf_event_max_stack),
> - .mode = 0644,
> + .mode = 0644 | SYSCTL_FLAG_MIN | SYSCTL_FLAG_MAX,
> .proc_handler = perf_event_max_stack_handler,
> - .extra1 = SYSCTL_ZERO,
> - .extra2 = (void *)&six_hundred_forty_kb,
> + .min = 0,
> + .max = 640 * 1024,
> },
> {
> .procname = "perf_event_max_contexts_per_stack",
> --
> 2.25.1
>

--

Joel Granados