Hi James,
On 2/7/25 12:18, James Morse wrote:
> mon_event_config_{read,write}() are called via IPI and access model
> specific registers to do their work.
>
> To support another architecture, this needs abstracting.
>
> Rename mon_event_config_{read,write}() to have a "resctrl_arch_"
> prefix, and move their struct mon_config_info parameter into
> <linux/resctrl.h>. This allows another architecture to supply an
> implementation of these.
>
> As struct mon_config_info is now exposed globally, give it a 'resctrl_'
> prefix. MPAM systems need access to the domain to do this work, add
> the resource and domain to struct resctrl_mon_config_info.
>
> Co-developed-by: Dave Martin <Dave.Martin@arm.com>
> Signed-off-by: Dave Martin <Dave.Martin@arm.com>
> Signed-off-by: James Morse <james.morse@arm.com>
> Tested-by: Carl Worth <carl@os.amperecomputing.com> # arm64
> Tested-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Reviewed-by: Shaopeng Tan <tan.shaopeng@jp.fujitsu.com>
> Reviewed-by: Tony Luck <tony.luck@intel.com>
> ---
> Changes since v5:
> * Renamed info to config_info.
> * Added description of which fields are read and written in the structure.
> * Clarified comment about which CPU this is called on for both kinds of
> reader.
>
> Changes since v3:
> * Added comments over the read/write helper to explain the type of the void
> pointer.
>
> Changes since v1:
> * [Whitespace only] Re-tabbed struct resctrl_mon_config_info in
> <linux/resctrl.h> to fit the prevailing style.
>
> Non-functional change.
>
> * [Commit message only] Reword to align with the actual naming of the
> definitions and destination header file.
> ---
> arch/x86/kernel/cpu/resctrl/rdtgroup.c | 46 +++++++++++++-------------
> include/linux/resctrl.h | 31 +++++++++++++++++
> 2 files changed, 54 insertions(+), 23 deletions(-)
>
> diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> index eb32fbc3abea..e7d1d8b6983d 100644
> --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c
> @@ -1580,11 +1580,6 @@ static int rdtgroup_size_show(struct kernfs_open_file *of,
> return ret;
> }
>
> -struct mon_config_info {
> - u32 evtid;
> - u32 mon_config;
> -};
> -
> #define INVALID_CONFIG_INDEX UINT_MAX
>
> /**
> @@ -1609,31 +1604,32 @@ static inline unsigned int mon_event_config_index_get(u32 evtid)
> }
> }
>
> -static void mon_event_config_read(void *info)
> +void resctrl_arch_mon_event_config_read(void *_config_info)
> {
> - struct mon_config_info *mon_info = info;
> + struct resctrl_mon_config_info *config_info = _config_info;
> unsigned int index;
> u64 msrval;
>
> - index = mon_event_config_index_get(mon_info->evtid);
> + index = mon_event_config_index_get(config_info->evtid);
> if (index == INVALID_CONFIG_INDEX) {
> - pr_warn_once("Invalid event id %d\n", mon_info->evtid);
> + pr_warn_once("Invalid event id %d\n", config_info->evtid);
> return;
> }
> rdmsrl(MSR_IA32_EVT_CFG_BASE + index, msrval);
>
> /* Report only the valid event configuration bits */
> - mon_info->mon_config = msrval & MAX_EVT_CONFIG_BITS;
> + config_info->mon_config = msrval & MAX_EVT_CONFIG_BITS;
> }
>
> -static void mondata_config_read(struct rdt_mon_domain *d, struct mon_config_info *mon_info)
> +static void mondata_config_read(struct resctrl_mon_config_info *mon_info)
> {
> - smp_call_function_any(&d->hdr.cpu_mask, mon_event_config_read, mon_info, 1);
> + smp_call_function_any(&mon_info->d->hdr.cpu_mask,
> + resctrl_arch_mon_event_config_read, mon_info, 1);
> }
>
> static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid)
> {
> - struct mon_config_info mon_info;
> + struct resctrl_mon_config_info mon_info;
> struct rdt_mon_domain *dom;
> bool sep = false;
>
> @@ -1644,9 +1640,11 @@ static int mbm_config_show(struct seq_file *s, struct rdt_resource *r, u32 evtid
> if (sep)
> seq_puts(s, ";");
>
> - memset(&mon_info, 0, sizeof(struct mon_config_info));
> + memset(&mon_info, 0, sizeof(struct resctrl_mon_config_info));
> + mon_info.r = r;
> + mon_info.d = dom;
> mon_info.evtid = evtid;
> - mondata_config_read(dom, &mon_info);
> + mondata_config_read(&mon_info);
>
> seq_printf(s, "%d=0x%02x", dom->hdr.id, mon_info.mon_config);
> sep = true;
> @@ -1679,30 +1677,32 @@ static int mbm_local_bytes_config_show(struct kernfs_open_file *of,
> return 0;
> }
>
> -static void mon_event_config_write(void *info)
> +void resctrl_arch_mon_event_config_write(void *_config_info)
> {
> - struct mon_config_info *mon_info = info;
> + struct resctrl_mon_config_info *config_info = _config_info;
> unsigned int index;
>
> - index = mon_event_config_index_get(mon_info->evtid);
> + index = mon_event_config_index_get(config_info->evtid);
> if (index == INVALID_CONFIG_INDEX) {
> - pr_warn_once("Invalid event id %d\n", mon_info->evtid);
> + pr_warn_once("Invalid event id %d\n", config_info->evtid);
> return;
> }
> - wrmsr(MSR_IA32_EVT_CFG_BASE + index, mon_info->mon_config, 0);
> + wrmsr(MSR_IA32_EVT_CFG_BASE + index, config_info->mon_config, 0);
> }
>
> static void mbm_config_write_domain(struct rdt_resource *r,
> struct rdt_mon_domain *d, u32 evtid, u32 val)
> {
> - struct mon_config_info mon_info = {0};
> + struct resctrl_mon_config_info mon_info = {0};
>
> /*
> * Read the current config value first. If both are the same then
> * no need to write it again.
> */
> + mon_info.r = r;
> + mon_info.d = d;
> mon_info.evtid = evtid;
> - mondata_config_read(d, &mon_info);
> + mondata_config_read(&mon_info);
> if (mon_info.mon_config == val)
> return;
>
> @@ -1714,7 +1714,7 @@ static void mbm_config_write_domain(struct rdt_resource *r,
> * are scoped at the domain level. Writing any of these MSRs
> * on one CPU is observed by all the CPUs in the domain.
> */
> - smp_call_function_any(&d->hdr.cpu_mask, mon_event_config_write,
> + smp_call_function_any(&d->hdr.cpu_mask, resctrl_arch_mon_event_config_write,
> &mon_info, 1);
>
> /*
> diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h
> index 5c7b9760b63a..59d944e139f8 100644
> --- a/include/linux/resctrl.h
> +++ b/include/linux/resctrl.h
> @@ -270,6 +270,13 @@ struct resctrl_cpu_defaults {
> u32 rmid;
> };
>
> +struct resctrl_mon_config_info {
> + struct rdt_resource *r;
> + struct rdt_mon_domain *d;
> + u32 evtid;
> + u32 mon_config;
> +};
Isn't this architecture specific definition? Why is this in common
resctrl.h file.
> +
> /**
> * resctrl_arch_sync_cpu_closid_rmid() - Refresh this CPU's CLOSID and RMID.
> * Call via IPI.
> @@ -311,6 +318,30 @@ int resctrl_arch_update_domains(struct rdt_resource *r, u32 closid);
>
> bool __init resctrl_arch_is_evt_configurable(enum resctrl_event_id evt);
>
> +/**
> + * resctrl_arch_mon_event_config_write() - Write the config for an event.
> + * @config_info: struct resctrl_mon_config_info describing the resource, domain
> + * and event.
> + *
> + * Reads resource, domain and eventid from @config_info and writes the
> + * event config_info->mon_config into hardware.
> + *
> + * Called via IPI to reach a CPU that is a member of the specified domain.
> + */
> +void resctrl_arch_mon_event_config_write(void *config_info);
> +
> +/**
> + * resctrl_arch_mon_event_config_read() - Read the config for an event.
> + * @config_info: struct resctrl_mon_config_info describing the resource, domain
> + * and event.
> + *
> + * Reads resource, domain and eventid from @config_info and reads the
> + * hardware config value into config_info->mon_config.
> + *
> + * Called via IPI to reach a CPU that is a member of the specified domain.
> + */
> +void resctrl_arch_mon_event_config_read(void *config_info);
> +
> /*
> * Update the ctrl_val and apply this config right now.
> * Must be called on one of the domain's CPUs.
--
Thanks
Babu Moger