> -----Original Message-----
> From: linux-edac-ow...@vger.kernel.org <linux-edac-ow...@vger.kernel.org> On
> Behalf Of Borislav Petkov
> Sent: Tuesday, May 21, 2019 6:09 PM
> To: Luck, Tony <tony.l...@intel.com>
> Cc: Ghannam, Yazen <yazen.ghan...@amd.com>; linux-e...@vger.kernel.org;
> linux-kernel@vger.kernel.org; x...@kernel.org
> Subject: Re: [PATCH v3 4/6] x86/MCE: Make number of MCA banks per_cpu
>
>
> On Tue, May 21, 2019 at 01:42:40PM -0700, Luck, Tony wrote:
> > On Tue, May 21, 2019 at 10:29:02PM +0200, Borislav Petkov wrote:
> > >
> > > Can we do instead:
> > >
> > > -static DEFINE_PER_CPU_READ_MOSTLY(struct mce_bank *, mce_banks_array);
> > > +static DEFINE_PER_CPU_READ_MOSTLY(struct mce_bank,
> > > mce_banks_array[MAX_NR_BANKS]);
> > >
> > > which should be something like 9*32 = 288 bytes per CPU.
> > >
> >
> > Where did you get the "9" from? struct mce_bank looks to
> > be over 50 bytes.
>
> Patch 2/6 changes that:
>
> struct mce_bank {
> u64 ctl; /* subevents to
> enable */
> bool init; /* initialise bank? */
> +};
> +static DEFINE_PER_CPU_READ_MOSTLY(struct mce_bank *, mce_banks_percpu);
> +
> +#define ATTR_LEN 16
> +/* One object for each MCE bank, shared by all CPUs */
> +struct mce_bank_dev {
> struct device_attribute attr; /* device attribute */
> char attrname[ATTR_LEN]; /* attribute name */
> + u8 bank; /* bank number */
> };
> +static struct mce_bank_dev mce_bank_devs[MAX_NR_BANKS];
>
> > Still only 1.5K per cpu though.
>
> Yah, I think that using static per-CPU memory should be better than
> GFP_ATOMIC.
>
Okay, makes sense. I'll send a patch soon.
Thanks,
Yazen
