On Thu, 8 Sep 2016, Srinivas Pandruvada wrote:
> From: Tim Chen <[email protected]>
>
> We uses ASYM_PACKING feature in the scheduler to move tasks to more
> capable cpus that can be boosted to higher frequency. This is enabled by
> Intel Turbo Boost Max Technology 3.0 (ITMT). We mark the sched domain
> topology level with SD_ASYM_PACKING flag for such systems to indicate
> scheduler can use the ASYM_PACKING feature to move load to the
> more capable cpus.
Sigh. This changelog does not tell anything about the nature of the patch,
the rationale for it etc. It's just a meaningless blurb.
> +unsigned int __read_mostly sysctl_sched_itmt_enabled;
> +
> static inline void smpboot_setup_warm_reset_vector(unsigned long start_eip)
> {
> unsigned long flags;
> @@ -471,31 +473,57 @@ static bool match_die(struct cpuinfo_x86 *c, struct
> cpuinfo_x86 *o)
> return false;
> }
>
> -static struct sched_domain_topology_level numa_inside_package_topology[] = {
> +#ifdef CONFIG_SCHED_ITMT
> +static int x86_core_flags(void)
> +{
> + int flags = cpu_core_flags();
> +
> + if (sysctl_sched_itmt_enabled)
> + flags |= SD_ASYM_PACKING;
> +
> + return flags;
> +}
> +
> +static int x86_smt_flags(void)
> +{
> + int flags = cpu_smt_flags();
> +
> + if (sysctl_sched_itmt_enabled)
> + flags |= SD_ASYM_PACKING;
> +
> + return flags;
> +}
> +#else
> +#define x86_core_flags cpu_core_flags
> +#define x86_smt_flags cpu_smt_flags
> +#endif
No. We first rework the code so that the IMT stuff can be added in a later
patch easily.
Thanks,
tglx
