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From: Florian Weimer <fweimer@redhat.com>
To: Adhemerval Zanella via Libc-alpha <libc-alpha@sourceware.org>
Cc: Robert O'Callahan <robert@ocallahan.org>,  Andreas Schwab
 <schwab@linux-m68k.org>,  Adhemerval Zanella
 <adhemerval.zanella@linaro.org>
Subject: Re: [PATCH] linux: Use /sys/devices/system/cpu on __get_nprocs_conf
 (BZ#28991)
References: <20220323203835.3653589-1-adhemerval.zanella@linaro.org>
Date: Mon, 16 May 2022 13:42:22 +0200
In-Reply-To: <20220323203835.3653589-1-adhemerval.zanella@linaro.org>
 (Adhemerval Zanella via Libc-alpha's message of "Wed, 23 Mar 2022
 17:38:35 -0300")
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* Adhemerval Zanella via Libc-alpha:

> @@ -239,8 +213,7 @@ get_nprocs_fallback (void)
>  int
>  __get_nprocs (void)
>  {
> -  /* Try /sys/devices/system/cpu/online first.  */
> -  int result = get_nprocs_cpu_online ();
> +  int result = read_sysfs_file ("/sys/devices/system/cpu/online");
>    if (result != 0)
>      return result;
>  
> @@ -255,8 +228,7 @@ weak_alias (__get_nprocs, get_nprocs)
>  int
>  __get_nprocs_conf (void)
>  {
> -  /* Try /sys/devices/system/cpu/ first.  */
> -  int result = get_nprocs_cpu ();
> +  int result = read_sysfs_file ("/sys/devices/system/cpu/possible");
>    if (result != 0)
>      return result;

I reviewed the kernel documentation and a tiny part of the kernel
sources, and I think this change is okay.

Reviewed-by: Florian Weimer <fweimer@redhat.com>

(It still does not give you the maximum CPU *index*, but that's okay.)

Thanks,
Florian