On 8/24/22 16:16, Reinette Chatre wrote: > Hi Babu, > > On 8/22/2022 6:44 AM, Babu Moger wrote: >> The current event configuration can be viewed by the user by reading >> the sysfs configuration file. >> >> 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 >> >> By default the mbm_total_bytes configuration is set to 0x7f to count >> all the types of events and mbm_local_bytes configuration is set to >> 0x15 to count all the local memory events. >> >> $cat /sys/fs/resctrl/mon_data/mon_L3_00/mbm_total_config >> 0x7f >> >> $cat /sys/fs/resctrl/mon_data/mon_L3_00/mbm_local_config >> 0x15 >> >> Signed-off-by: Babu Moger <babu.moger@xxxxxxx> >> Reviewed-by: Ingo Molnar <mingo@xxxxxxxxxx> >> --- >> arch/x86/kernel/cpu/resctrl/internal.h | 21 ++++++++++ >> arch/x86/kernel/cpu/resctrl/rdtgroup.c | 70 ++++++++++++++++++++++++++++++++ >> 2 files changed, 91 insertions(+) >> >> diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h >> index fc725f5e9024..457666709386 100644 >> --- a/arch/x86/kernel/cpu/resctrl/internal.h >> +++ b/arch/x86/kernel/cpu/resctrl/internal.h >> @@ -15,6 +15,7 @@ >> #define MSR_IA32_MBA_THRTL_BASE 0xd50 >> #define MSR_IA32_MBA_BW_BASE 0xc0000200 >> #define MSR_IA32_SMBA_BW_BASE 0xc0000280 >> +#define MSR_IA32_EVT_CFG_BASE 0xc0000400 >> >> #define MSR_IA32_QM_CTR 0x0c8e >> #define MSR_IA32_QM_EVTSEL 0x0c8d >> @@ -50,6 +51,26 @@ >> */ >> #define MBM_CNTR_WIDTH_OFFSET_MAX (62 - MBM_CNTR_WIDTH_BASE) >> >> +/* Reads to Local DRAM Memory */ >> +#define READS_TO_LOCAL_MEM BIT(0) >> + >> +/* Reads to Remote DRAM Memory */ >> +#define READS_TO_REMOTE_MEM BIT(1) >> + >> +/* Non-Temporal Writes to Local Memory */ >> +#define NON_TEMP_WRITE_TO_LOCAL_MEM BIT(2) >> + >> +/* Non-Temporal Writes to Remote Memory */ >> +#define NON_TEMP_WRITE_TO_REMOTE_MEM BIT(3) >> + >> +/* Reads to Local Memory the system identifies as "Slow Memory" */ > Seems unexpected character slipped into "identifies". Sure. Will fix it > >> +#define READS_TO_LOCAL_S_MEM BIT(4) >> + >> +/* Reads to Remote Memory the system identifies as "Slow Memory" */ > here also sure. Will fix it. > >> +#define READS_TO_REMOTE_S_MEM BIT(5) >> + >> +/* Dirty Victims to All Types of Memory */ >> +#define DIRTY_VICTIS_TO_ALL_MEM BIT(6) > Is this intended to be "DIRTY_VICTIMS_TO_ALL_MEM" ? Yes. that is what spec says. > >> >> struct rdt_fs_context { >> struct kernfs_fs_context kfc; >> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c >> index 30d2182d4fda..e1847d49fa15 100644 >> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c >> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c >> @@ -254,8 +254,78 @@ static const struct kernfs_ops kf_mondata_ops = { >> .seq_show = rdtgroup_mondata_show, >> }; >> >> +/* >> + * This is called via IPI to read the CQM/MBM counters >> + * in a domain. >> + */ >> +void mon_event_config_read(void *info) >> +{ >> + union mon_data_bits *md = info; >> + u32 evtid = md->u.evtid; >> + u32 h, msr_index; >> + >> + switch (evtid) { >> + case QOS_L3_MBM_TOTAL_EVENT_ID: >> + msr_index = 0; >> + break; >> + case QOS_L3_MBM_LOCAL_EVENT_ID: >> + msr_index = 1; >> + break; >> + default: >> + return; /* Not expected to come here */ > Please no inline comments. Ok > >> + } >> + >> + rdmsr(MSR_IA32_EVT_CFG_BASE + msr_index, md->u.mon_config, h); >> +} >> + >> +void mondata_config_read(struct rdt_domain *d, union mon_data_bits *md) >> +{ >> + smp_call_function_any(&d->cpu_mask, mon_event_config_read, md, 1); >> +} >> + >> +int rdtgroup_mondata_config_show(struct seq_file *m, void *arg) >> +{ >> + struct kernfs_open_file *of = m->private; >> + struct rdt_hw_resource *hw_res; >> + u32 resid, evtid, domid; >> + struct rdtgroup *rdtgrp; >> + struct rdt_resource *r; >> + union mon_data_bits md; >> + struct rdt_domain *d; >> + int ret = 0; >> + >> + rdtgrp = rdtgroup_kn_lock_live(of->kn); >> + if (!rdtgrp) { >> + ret = -ENOENT; >> + goto out; >> + } >> + >> + md.priv = of->kn->priv; >> + resid = md.u.rid; >> + domid = md.u.domid; >> + evtid = md.u.evtid; >> + >> + hw_res = &rdt_resources_all[resid]; >> + r = &hw_res->r_resctrl; >> + >> + d = rdt_find_domain(r, domid, NULL); >> + if (IS_ERR_OR_NULL(d)) { >> + ret = -ENOENT; >> + goto out; >> + } >> + >> + mondata_config_read(d, &md); >> + >> + seq_printf(m, "0x%x\n", md.u.mon_config); > Looking at this patch and the next, the sysfs files are introduced to read > from and write to the configuration register. From what I can tell the > data is never used internally (what did I miss?). Why is the value of the > configuration register stored? You didn't miss anything. We don't need to store it. But we need it as part of mon_data_bits structure because, it need to be passed to mon_event_config_read and rdtgroup_mondata_config_write. In these functions we need evtid and also config value (mon_config). Thanks Babu > >> + >> +out: >> + rdtgroup_kn_unlock(of->kn); >> + return ret; >> +} >> + >> static const struct kernfs_ops kf_mondata_config_ops = { >> .atomic_write_len = PAGE_SIZE, >> + .seq_show = rdtgroup_mondata_config_show, >> }; >> >> static bool is_cpu_list(struct kernfs_open_file *of) >> >> > > Reinette -- Thanks Babu Moger