Hi Peter,
On 4/21/2023 7:17 AM, Peter Newman wrote:
When RMIDs are soft, __mon_event_count() only needs to report the current byte count in memory and should not touch the hardware RMIDs.
Create a parallel version for the soft RMID configuration and update __mon_event_count() to choose between it and the original depending on whether the soft RMID static key is enabled.
Please note that the changelog refers to "whether the soft RMID static key is enabled" but the patch uses a bool instead of a static key.
Signed-off-by: Peter Newman peternewman@google.com
arch/x86/kernel/cpu/resctrl/monitor.c | 33 ++++++++++++++++++++++++++- 1 file changed, 32 insertions(+), 1 deletion(-)
diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c index bb857eefa3b0..3d54a634471a 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -487,7 +487,30 @@ void resctrl_mbm_flush_cpu(void) __mbm_flush(QOS_L3_MBM_TOTAL_EVENT_ID, r, d); } -static int __mon_event_count(u32 rmid, struct rmid_read *rr) +static int __mon_event_count_soft_rmid(u32 rmid, struct rmid_read *rr) +{
- struct mbm_state *m;
- WARN_ON(!is_mbm_event(rr->evtid));
- m = get_mbm_state(rr->d, rmid, rr->evtid);
- if (!m)
/* implies !is_mbm_event(...) */return -1;- rr->val += atomic64_read(&m->soft_rmid_bytes);
- if (rr->first) {
/** Discard any bandwidth resulting from the initial HW counter* reads.*/atomic64_set(&m->soft_rmid_bytes, 0);- }
The above is not clear to me. If rr->first is true then it would read soft_rmid_bytes and then immediately reset it?
Reinette