| 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
| ||
|
Message-ID: <1cc4ffae-3d36-b369-7cc9-b7130701b944@amd.com>
Date: Mon, 7 Nov 2022 12:50:35 -0600
From: "Moger, Babu" <babu.moger@....com>
To: Peter Newman <peternewman@...gle.com>
Cc: akpm@...ux-foundation.org, bagasdotme@...il.com, bp@...en8.de,
chang.seok.bae@...el.com, corbet@....net,
damien.lemoal@...nsource.wdc.com, daniel.sneddon@...ux.intel.com,
dave.hansen@...ux.intel.com, eranian@...gle.com,
fenghua.yu@...el.com, hpa@...or.com, james.morse@....com,
jmattson@...gle.com, jpoimboe@...nel.org,
linux-doc@...r.kernel.org, linux-kernel@...r.kernel.org,
mingo@...hat.com, paulmck@...nel.org,
pawan.kumar.gupta@...ux.intel.com, pbonzini@...hat.com,
peterz@...radead.org, quic_neeraju@...cinc.com,
rdunlap@...radead.org, reinette.chatre@...el.com,
sandipan.das@....com, songmuchun@...edance.com, tglx@...utronix.de,
tony.luck@...el.com, x86@...nel.org
Subject: Re: [PATCH v8 10/13] x86/resctrl: Add sysfs interface to write
mbm_total_bytes_config
Hi Peter,
On 11/7/22 04:21, Peter Newman wrote:
> Hi Babu,
>
> On Fri, Nov 04, 2022 at 03:01:09PM -0500, Babu Moger wrote:
>> + /*
>> + * When an Event Configuration is changed, the bandwidth counters
>> + * for all RMIDs and Events will be cleared by the hardware. The
>> + * hardware also sets MSR_IA32_QM_CTR.Unavailable (bit 62) for
>> + * every RMID on the next read to any event for every RMID.
>> + * Subsequent reads will have MSR_IA32_QM_CTR.Unavailable (bit 62)
>> + * cleared while it is tracked by the hardware. Clear the
>> + * mbm_local and mbm_total counts for all the RMIDs.
>> + */
>> + memset(d->mbm_local, 0, sizeof(struct mbm_state) * r->num_rmid);
>> + memset(d->mbm_total, 0, sizeof(struct mbm_state) * r->num_rmid);
> Looking around, I can't find a reader for mbm_total anymore. It looks
> like the last place it was used went away in James's recent change:
>
> https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Flore.kernel.org%2Fall%2F20220902154829.30399-19-james.morse%40arm.com&data=05%7C01%7Cbabu.moger%40amd.com%7C84a9d0f934894a3031a608dac0a9db33%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C638034133003350939%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=i3isjCzxnBp4b2VblC7ZpH3hShUEe7unKiKfngG1kzE%3D&reserved=0
>
> Are we supposed to be clearing arch_mbm_total now?
Yes. You are right. We should be using resctrl_arch_reset_rmid to reset
the rmids here.
This patch should work. Will fix it in next revision after the other comments.
diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
b/arch/x86/kernel/cpu/resctrl/rdtgroup.c │
index 6b222f8e58ae..28d9d99a639e
100644 │
---
a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
│
+++
b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
│
@@ -1517,7 +1517,7 @@ static int mbm_config_write(struct rdt_resource *r,
struct rdt_domain *d, │
u32 evtid, u32
val) │
{
│
struct mon_config_info mon_info =
{0}; │
- int ret =
0;
│
+ int ret = 0,
i;
│
│
rdt_last_cmd_clear();
│
│
@@ -1557,8 +1557,10 @@ static int mbm_config_write(struct rdt_resource *r,
struct rdt_domain *d, │
* cleared while it is tracked by the hardware. Clear
the │
* mbm_local and mbm_total counts for all the
RMIDs. │
*/
│
- memset(d->mbm_local, 0, sizeof(struct mbm_state) *
r->num_rmid); │
- memset(d->mbm_total, 0, sizeof(struct mbm_state) *
r->num_rmid); │
+ for (i = 0; i < r->num_rmid; i++)
{ │
+ resctrl_arch_reset_rmid(r, d, i,
QOS_L3_MBM_TOTAL_EVENT_ID); │
+ resctrl_arch_reset_rmid(r, d, i,
QOS_L3_MBM_LOCAL_EVENT_ID); │
+
}
│
│
write_exit:
│
return ret;
Thanks
Babu
Powered by blists - more mailing lists