[AMD Official Use Only - General]
Hi Reinette,
> -----Original Message-----
> From: Reinette Chatre <reinette.chatre@xxxxxxxxx>
> Sent: Thursday, December 15, 2022 12:26 PM
> To: Moger, Babu <Babu.Moger@xxxxxxx>; corbet@xxxxxxx;
> tglx@xxxxxxxxxxxxx; mingo@xxxxxxxxxx; bp@xxxxxxxxx
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> Subject: Re: [PATCH v9 11/13] x86/resctrl: Add sysfs interface to write
> mbm_local_bytes_config
>
> Hi Babu,
>
> On 12/1/2022 7:37 AM, Babu Moger wrote:
> > The current event configuration for mbm_local_bytes can be changed by
> > the user by writing to the configuration file
> > /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config.
> >
>
> Same comments about subject line and usage of "current".
Sure,
>
> > The event configuration settings are domain specific and will affect
> > all the CPUs in the domain.
> >
> > Following are the types of events supported:
> > ====
> ===========================================================
> > Bits Description
> > ====
> ===========================================================
> > 6 Dirty Victims from the QOS domain to all types of memory
> > 5 Reads to slow memory in the non-local NUMA domain
> > 4 Reads to slow memory in the local NUMA domain
> > 3 Non-temporal writes to non-local NUMA domain
> > 2 Non-temporal writes to local NUMA domain
> > 1 Reads to memory in the non-local NUMA domain
> > 0 Reads to memory in the local NUMA domain
> > ====
> ===========================================================
> >
> > For example:
> > To change the mbm_local_bytes_config to count all the non-temporal
> > writes on domain 0, the bits 2 and 3 needs to be set which is 1100b (in hex
> 0xc).
> > Run the command.
> > $echo 0=0xc > /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config
> >
> > To change the mbm_local_bytes to count only reads to local NUMA domain
> > 1, the bit 0 needs to be set which 1b (in hex 0x1). Run the command.
> > $echo 1=0x1 > /sys/fs/resctrl/info/L3_MON/mbm_local_bytes_config
> >
> > Signed-off-by: Babu Moger <babu.moger@xxxxxxx>
> > ---
> > arch/x86/kernel/cpu/resctrl/rdtgroup.c | 29
> ++++++++++++++++++++++++++++-
> > 1 file changed, 28 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > index 8a22a652a6e8..6897c480ae55 100644
> > --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> > @@ -1641,6 +1641,32 @@ static ssize_t
> mbm_total_bytes_config_write(struct kernfs_open_file *of,
> > return ret ?: nbytes;
> > }
> >
> > +static ssize_t mbm_local_bytes_config_write(struct kernfs_open_file *of,
> > + char *buf, size_t nbytes,
> > + loff_t off)
> > +{
> > + struct rdt_resource *r = of->kn->parent->priv;
> > + int ret;
> > +
> > + /* Valid input requires a trailing newline */
> > + if (nbytes == 0 || buf[nbytes - 1] != '\n')
> > + return -EINVAL;
> > +
> > + cpus_read_lock();
> > + mutex_lock(&rdtgroup_mutex);
> > +
> > + rdt_last_cmd_clear();
> > +
> > + buf[nbytes - 1] = '\0';
> > +
> > + ret = mon_config_write(r, buf, QOS_L3_MBM_LOCAL_EVENT_ID);
> > +
> > + mutex_unlock(&rdtgroup_mutex);
> > + cpus_read_unlock();
> > +
> > + return ret ?: nbytes;
> > +}
> > +
> > /* rdtgroup information files for one cache resource. */ static
> > struct rftype res_common_files[] = {
> > {
> > @@ -1748,9 +1774,10 @@ static struct rftype res_common_files[] = {
> > },
> > {
> > .name = "mbm_local_bytes_config",
> > - .mode = 0444,
> > + .mode = 0644,
> > .kf_ops = &rdtgroup_kf_single_ops,
> > .seq_show = mbm_local_bytes_config_show,
> > + .write = mbm_local_bytes_config_write,
> > },
> > {
> > .name = "cpus",
> >
> >
>
> With the subject and changelog comments addressed:
>
> Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx>
Thanks
Babu
>
> Reinette
