linux-kernel - Re: [PATCH v2 4/4] thermal: intel: hfi: Increase the number of CPU capabilities per netlink event

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <27ccbb20741b2a2f86074f0ac4bda61aadc9faa3.camel@intel.com>
Date: Wed, 8 May 2024 04:47:22 +0000
From: "Zhang, Rui" <rui.zhang@...el.com>
To: "ricardo.neri-calderon@...ux.intel.com"
	<ricardo.neri-calderon@...ux.intel.com>, "Wysocki, Rafael J"
	<rafael.j.wysocki@...el.com>
CC: "srinivas.pandruvada@...ux.intel.com"
	<srinivas.pandruvada@...ux.intel.com>, "Brown, Len" <len.brown@...el.com>,
	"stanislaw.gruszka@...ux.intel.com" <stanislaw.gruszka@...ux.intel.com>,
	"linux-pm@...r.kernel.org" <linux-pm@...r.kernel.org>,
	"linux-kernel@...r.kernel.org" <linux-kernel@...r.kernel.org>, "Neri,
 Ricardo" <ricardo.neri@...el.com>
Subject: Re: [PATCH v2 4/4] thermal: intel: hfi: Increase the number of CPU
 capabilities per netlink event

On Tue, 2024-05-07 at 20:43 -0700, Ricardo Neri wrote:
> The number of updated CPU capabilities per netlink event is hard-
> coded to
> 16. On systems with more than 16 CPUs (a common case), it takes more
> than
> one thermal netlink event to relay all the new capabilities after an
> HFI
> interrupt. This adds unnecessary overhead to both the kernel and user
> space
> entities.
> 
> Increase the number of CPU capabilities updated per event to 64. Any
> system
> with 64 CPUs or less can now update all the capabilities in a single
> thermal netlink event.
> 
> Signed-off-by: Ricardo Neri <ricardo.neri-calderon@...ux.intel.com>

Acked-by: Zhang Rui <rui.zhang@...el.com>

-rui
> ---
> Cc: Len Brown <len.brown@...el.com>
> Cc: Srinivas Pandruvada <srinivas.pandruvada@...ux.intel.com>
> Cc: Stanislaw Gruszka <stanislaw.gruszka@...ux.intel.com>
> Cc: Zhang Rui <rui.zhang@...el.com>
> Cc: linux-pm@...r.kernel.org
> Cc: linux-kernel@...r.kernel.org
> ---
> Changes since v2:
>  * Dropped the debugfs interface. Instead, increased the size of the
>    thermal netlink message size to 64 CPU capabilities.
> ---
>  drivers/thermal/intel/intel_hfi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/thermal/intel/intel_hfi.c
> b/drivers/thermal/intel/intel_hfi.c
> index c6658f8c5cca..a180a98bb9f1 100644
> --- a/drivers/thermal/intel/intel_hfi.c
> +++ b/drivers/thermal/intel/intel_hfi.c
> @@ -167,7 +167,7 @@ static DEFINE_MUTEX(hfi_instance_lock);
>  
>  static struct workqueue_struct *hfi_updates_wq;
>  #define HFI_UPDATE_DELAY_MS            100
> -#define HFI_THERMNL_CAPS_PER_EVENT     16
> +#define HFI_THERMNL_CAPS_PER_EVENT     64
>  
>  static void get_hfi_caps(struct hfi_instance *hfi_instance,
>                          struct thermal_genl_cpu_caps *cpu_caps)