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. 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",