Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
fs/resctrl: Introduce mbm_assign_on_mkdir to enable assignments on mkdir
The "mbm_event" counter assignment mode allows users to assign a hardware
counter to an RMID, event pair and monitor the bandwidth as long as it is
assigned.
Introduce a user-configurable option that determines if a counter will
automatically be assigned to an RMID, event pair when its associated
monitor group is created via mkdir. Accessible when "mbm_event" counter
assignment mode is enabled.
Suggested-by: Peter Newman <peternewman@google.com>
Signed-off-by: Babu Moger <babu.moger@amd.com>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/cover.1757108044.git.babu.moger@amd.com
authored by
Babu Moger
and committed by
Borislav Petkov (AMD)
ac1df9bb
f9ae5913
+89
+20
Documentation/filesystems/resctrl.rst
+20
Documentation/filesystems/resctrl.rst
···
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# cat /sys/fs/resctrl/info/L3_MON/event_configs/mbm_total_bytes/event_filter
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local_reads,local_non_temporal_writes
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"mbm_assign_on_mkdir":
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Exists when "mbm_event" counter assignment mode is supported. Accessible
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only when "mbm_event" counter assignment mode is enabled.
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Determines if a counter will automatically be assigned to an RMID, MBM event
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pair when its associated monitor group is created via mkdir. Enabled by default
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on boot, also when switched from "default" mode to "mbm_event" counter assignment
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mode. Users can disable this capability by writing to the interface.
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"0":
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Auto assignment is disabled.
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"1":
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Auto assignment is enabled.
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Example::
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# echo 0 > /sys/fs/resctrl/info/L3_MON/mbm_assign_on_mkdir
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# cat /sys/fs/resctrl/info/L3_MON/mbm_assign_on_mkdir
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0
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+
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"max_threshold_occupancy":
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Read/write file provides the largest value (in
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bytes) at which a previously used LLC_occupancy
+6
fs/resctrl/internal.h
+6
fs/resctrl/internal.h
···
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ssize_t event_filter_write(struct kernfs_open_file *of, char *buf, size_t nbytes,
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loff_t off);
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int resctrl_mbm_assign_on_mkdir_show(struct kernfs_open_file *of,
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struct seq_file *s, void *v);
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ssize_t resctrl_mbm_assign_on_mkdir_write(struct kernfs_open_file *of, char *buf,
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size_t nbytes, loff_t off);
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#ifdef CONFIG_RESCTRL_FS_PSEUDO_LOCK
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int rdtgroup_locksetup_enter(struct rdtgroup *rdtgrp);
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+53
fs/resctrl/monitor.c
+53
fs/resctrl/monitor.c
···
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return ret;
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}
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int resctrl_mbm_assign_on_mkdir_show(struct kernfs_open_file *of, struct seq_file *s,
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void *v)
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{
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struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
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int ret = 0;
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mutex_lock(&rdtgroup_mutex);
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rdt_last_cmd_clear();
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if (!resctrl_arch_mbm_cntr_assign_enabled(r)) {
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rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n");
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ret = -EINVAL;
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goto out_unlock;
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}
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seq_printf(s, "%u\n", r->mon.mbm_assign_on_mkdir);
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out_unlock:
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mutex_unlock(&rdtgroup_mutex);
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return ret;
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}
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ssize_t resctrl_mbm_assign_on_mkdir_write(struct kernfs_open_file *of, char *buf,
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size_t nbytes, loff_t off)
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{
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struct rdt_resource *r = rdt_kn_parent_priv(of->kn);
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bool value;
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int ret;
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ret = kstrtobool(buf, &value);
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if (ret)
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return ret;
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mutex_lock(&rdtgroup_mutex);
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rdt_last_cmd_clear();
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if (!resctrl_arch_mbm_cntr_assign_enabled(r)) {
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rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n");
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ret = -EINVAL;
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goto out_unlock;
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}
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r->mon.mbm_assign_on_mkdir = value;
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out_unlock:
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mutex_unlock(&rdtgroup_mutex);
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return ret ?: nbytes;
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}
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/*
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* rdtgroup_assign_cntr() - Assign/unassign the counter ID for the event, RMID
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* pair in the domain.
···
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resctrl_file_fflags_init("available_mbm_cntrs",
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RFTYPE_MON_INFO | RFTYPE_RES_CACHE);
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resctrl_file_fflags_init("event_filter", RFTYPE_ASSIGN_CONFIG);
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resctrl_file_fflags_init("mbm_assign_on_mkdir", RFTYPE_MON_INFO |
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RFTYPE_RES_CACHE);
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}
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return 0;
+7
fs/resctrl/rdtgroup.c
+7
fs/resctrl/rdtgroup.c
···
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.fflags = RFTYPE_TOP_INFO,
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},
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{
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.name = "mbm_assign_on_mkdir",
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.mode = 0644,
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.kf_ops = &rdtgroup_kf_single_ops,
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.seq_show = resctrl_mbm_assign_on_mkdir_show,
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.write = resctrl_mbm_assign_on_mkdir_write,
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},
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{
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.name = "num_closids",
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.mode = 0444,
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.kf_ops = &rdtgroup_kf_single_ops,
+3
include/linux/resctrl.h
+3
include/linux/resctrl.h
···
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* monitoring events can be configured.
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* @num_mbm_cntrs: Number of assignable counters.
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* @mbm_cntr_assignable:Is system capable of supporting counter assignment?
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* @mbm_assign_on_mkdir:True if counters should automatically be assigned to MBM
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* events of monitor groups created via mkdir.
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*/
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struct resctrl_mon {
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int num_rmid;
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unsigned int mbm_cfg_mask;
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int num_mbm_cntrs;
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bool mbm_cntr_assignable;
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bool mbm_assign_on_mkdir;
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};
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/**