Re: [PATCH v3 06/16] arch_topology: Add support to parse and detect cache attributes

[Gavin Shan]

Hi Sudeep,

On 5/25/22 4:14 PM, Sudeep Holla wrote:
> Currently ACPI populates just the minimum information about the last
> level cache from PPTT in order to feed the same to build sched_domains.
> Similar support for DT platforms is not present.
>
> In order to enable the same, the entire cache hierarchy information can
> be built as part of CPU topoplogy parsing both on ACPI and DT platforms.
>
> Note that this change builds the cacheinfo early even on ACPI systems, but
> the current mechanism of building llc_sibling mask remains unchanged.
>
> Signed-off-by: Sudeep Holla <sudeep.holla@xxxxxxx>
> ---
>   drivers/base/arch_topology.c | 23 ++++++++++++++++-------
>   1 file changed, 16 insertions(+), 7 deletions(-)

With below nits fixed:

Reviewed-by: Gavin Shan <gshan@xxxxxxxxxx>

> diff --git a/drivers/base/arch_topology.c b/drivers/base/arch_topology.c
> index f73b836047cf..765723448b10 100644
> --- a/drivers/base/arch_topology.c
> +++ b/drivers/base/arch_topology.c
> @@ -7,6 +7,7 @@
>    */
>   
>   #include <linux/acpi.h>
> +#include <linux/cacheinfo.h>
>   #include <linux/cpu.h>
>   #include <linux/cpufreq.h>
>   #include <linux/device.h>
> @@ -775,15 +776,23 @@ __weak int __init parse_acpi_topology(void)
>   #if defined(CONFIG_ARM64) || defined(CONFIG_RISCV)
>   void __init init_cpu_topology(void)
>   {
> +	int ret, cpu;
> +
>   	reset_cpu_topology();
> +	ret = parse_acpi_topology();
> +	if (!ret)
> +		ret = of_have_populated_dt() && parse_dt_topology();
>   
> -	/*
> -	 * Discard anything that was parsed if we hit an error so we
> -	 * don't use partial information.
> -	 */
> -	if (parse_acpi_topology())
> -		reset_cpu_topology();
> -	else if (of_have_populated_dt() && parse_dt_topology())
> +	if(ret) {
> +		/*
> +		 * Discard anything that was parsed if we hit an error so we
> +		 * don't use partial information.
> +		 */
>   		reset_cpu_topology();
> +		return;
> +	}
> +
> +	for_each_possible_cpu(cpu)
> +		detect_cache_attributes(cpu);
>   }
>   #endif

# ./scripts/checkpatch.pl --codespell patch/check/0006*
ERROR: space required before the open parenthesis '('
#55: FILE: drivers/base/arch_topology.c:786:
+	if(ret) {

Thanks,
Gavin