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Diffstat (limited to 'fs/resctrl/monitor.c')
| -rw-r--r-- | fs/resctrl/monitor.c | 1811 |
1 files changed, 1811 insertions, 0 deletions
diff --git a/fs/resctrl/monitor.c b/fs/resctrl/monitor.c new file mode 100644 index 000000000000..572a9925bd6c --- /dev/null +++ b/fs/resctrl/monitor.c @@ -0,0 +1,1811 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * Resource Director Technology(RDT) + * - Monitoring code + * + * Copyright (C) 2017 Intel Corporation + * + * Author: + * Vikas Shivappa <vikas.shivappa@intel.com> + * + * This replaces the cqm.c based on perf but we reuse a lot of + * code and datastructures originally from Peter Zijlstra and Matt Fleming. + * + * More information about RDT be found in the Intel (R) x86 Architecture + * Software Developer Manual June 2016, volume 3, section 17.17. + */ + +#define pr_fmt(fmt) "resctrl: " fmt + +#include <linux/cpu.h> +#include <linux/resctrl.h> +#include <linux/sizes.h> +#include <linux/slab.h> + +#include "internal.h" + +#define CREATE_TRACE_POINTS + +#include "monitor_trace.h" + +/** + * struct rmid_entry - dirty tracking for all RMID. + * @closid: The CLOSID for this entry. + * @rmid: The RMID for this entry. + * @busy: The number of domains with cached data using this RMID. + * @list: Member of the rmid_free_lru list when busy == 0. + * + * Depending on the architecture the correct monitor is accessed using + * both @closid and @rmid, or @rmid only. + * + * Take the rdtgroup_mutex when accessing. + */ +struct rmid_entry { + u32 closid; + u32 rmid; + int busy; + struct list_head list; +}; + +/* + * @rmid_free_lru - A least recently used list of free RMIDs + * These RMIDs are guaranteed to have an occupancy less than the + * threshold occupancy + */ +static LIST_HEAD(rmid_free_lru); + +/* + * @closid_num_dirty_rmid The number of dirty RMID each CLOSID has. + * Only allocated when CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID is defined. + * Indexed by CLOSID. Protected by rdtgroup_mutex. + */ +static u32 *closid_num_dirty_rmid; + +/* + * @rmid_limbo_count - count of currently unused but (potentially) + * dirty RMIDs. + * This counts RMIDs that no one is currently using but that + * may have a occupancy value > resctrl_rmid_realloc_threshold. User can + * change the threshold occupancy value. + */ +static unsigned int rmid_limbo_count; + +/* + * @rmid_entry - The entry in the limbo and free lists. + */ +static struct rmid_entry *rmid_ptrs; + +/* + * This is the threshold cache occupancy in bytes at which we will consider an + * RMID available for re-allocation. + */ +unsigned int resctrl_rmid_realloc_threshold; + +/* + * This is the maximum value for the reallocation threshold, in bytes. + */ +unsigned int resctrl_rmid_realloc_limit; + +/* + * x86 and arm64 differ in their handling of monitoring. + * x86's RMID are independent numbers, there is only one source of traffic + * with an RMID value of '1'. + * arm64's PMG extends the PARTID/CLOSID space, there are multiple sources of + * traffic with a PMG value of '1', one for each CLOSID, meaning the RMID + * value is no longer unique. + * To account for this, resctrl uses an index. On x86 this is just the RMID, + * on arm64 it encodes the CLOSID and RMID. This gives a unique number. + * + * The domain's rmid_busy_llc and rmid_ptrs[] are sized by index. The arch code + * must accept an attempt to read every index. + */ +static inline struct rmid_entry *__rmid_entry(u32 idx) +{ + struct rmid_entry *entry; + u32 closid, rmid; + + entry = &rmid_ptrs[idx]; + resctrl_arch_rmid_idx_decode(idx, &closid, &rmid); + + WARN_ON_ONCE(entry->closid != closid); + WARN_ON_ONCE(entry->rmid != rmid); + + return entry; +} + +static void limbo_release_entry(struct rmid_entry *entry) +{ + lockdep_assert_held(&rdtgroup_mutex); + + rmid_limbo_count--; + list_add_tail(&entry->list, &rmid_free_lru); + + if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) + closid_num_dirty_rmid[entry->closid]--; +} + +/* + * Check the RMIDs that are marked as busy for this domain. If the + * reported LLC occupancy is below the threshold clear the busy bit and + * decrement the count. If the busy count gets to zero on an RMID, we + * free the RMID + */ +void __check_limbo(struct rdt_mon_domain *d, bool force_free) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + u32 idx_limit = resctrl_arch_system_num_rmid_idx(); + struct rmid_entry *entry; + u32 idx, cur_idx = 1; + void *arch_mon_ctx; + bool rmid_dirty; + u64 val = 0; + + arch_mon_ctx = resctrl_arch_mon_ctx_alloc(r, QOS_L3_OCCUP_EVENT_ID); + if (IS_ERR(arch_mon_ctx)) { + pr_warn_ratelimited("Failed to allocate monitor context: %ld", + PTR_ERR(arch_mon_ctx)); + return; + } + + /* + * Skip RMID 0 and start from RMID 1 and check all the RMIDs that + * are marked as busy for occupancy < threshold. If the occupancy + * is less than the threshold decrement the busy counter of the + * RMID and move it to the free list when the counter reaches 0. + */ + for (;;) { + idx = find_next_bit(d->rmid_busy_llc, idx_limit, cur_idx); + if (idx >= idx_limit) + break; + + entry = __rmid_entry(idx); + if (resctrl_arch_rmid_read(r, d, entry->closid, entry->rmid, + QOS_L3_OCCUP_EVENT_ID, &val, + arch_mon_ctx)) { + rmid_dirty = true; + } else { + rmid_dirty = (val >= resctrl_rmid_realloc_threshold); + + /* + * x86's CLOSID and RMID are independent numbers, so the entry's + * CLOSID is an empty CLOSID (X86_RESCTRL_EMPTY_CLOSID). On Arm the + * RMID (PMG) extends the CLOSID (PARTID) space with bits that aren't + * used to select the configuration. It is thus necessary to track both + * CLOSID and RMID because there may be dependencies between them + * on some architectures. + */ + trace_mon_llc_occupancy_limbo(entry->closid, entry->rmid, d->hdr.id, val); + } + + if (force_free || !rmid_dirty) { + clear_bit(idx, d->rmid_busy_llc); + if (!--entry->busy) + limbo_release_entry(entry); + } + cur_idx = idx + 1; + } + + resctrl_arch_mon_ctx_free(r, QOS_L3_OCCUP_EVENT_ID, arch_mon_ctx); +} + +bool has_busy_rmid(struct rdt_mon_domain *d) +{ + u32 idx_limit = resctrl_arch_system_num_rmid_idx(); + + return find_first_bit(d->rmid_busy_llc, idx_limit) != idx_limit; +} + +static struct rmid_entry *resctrl_find_free_rmid(u32 closid) +{ + struct rmid_entry *itr; + u32 itr_idx, cmp_idx; + + if (list_empty(&rmid_free_lru)) + return rmid_limbo_count ? ERR_PTR(-EBUSY) : ERR_PTR(-ENOSPC); + + list_for_each_entry(itr, &rmid_free_lru, list) { + /* + * Get the index of this free RMID, and the index it would need + * to be if it were used with this CLOSID. + * If the CLOSID is irrelevant on this architecture, the two + * index values are always the same on every entry and thus the + * very first entry will be returned. + */ + itr_idx = resctrl_arch_rmid_idx_encode(itr->closid, itr->rmid); + cmp_idx = resctrl_arch_rmid_idx_encode(closid, itr->rmid); + + if (itr_idx == cmp_idx) + return itr; + } + + return ERR_PTR(-ENOSPC); +} + +/** + * resctrl_find_cleanest_closid() - Find a CLOSID where all the associated + * RMID are clean, or the CLOSID that has + * the most clean RMID. + * + * MPAM's equivalent of RMID are per-CLOSID, meaning a freshly allocated CLOSID + * may not be able to allocate clean RMID. To avoid this the allocator will + * choose the CLOSID with the most clean RMID. + * + * When the CLOSID and RMID are independent numbers, the first free CLOSID will + * be returned. + */ +int resctrl_find_cleanest_closid(void) +{ + u32 cleanest_closid = ~0; + int i = 0; + + lockdep_assert_held(&rdtgroup_mutex); + + if (!IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) + return -EIO; + + for (i = 0; i < closids_supported(); i++) { + int num_dirty; + + if (closid_allocated(i)) + continue; + + num_dirty = closid_num_dirty_rmid[i]; + if (num_dirty == 0) + return i; + + if (cleanest_closid == ~0) + cleanest_closid = i; + + if (num_dirty < closid_num_dirty_rmid[cleanest_closid]) + cleanest_closid = i; + } + + if (cleanest_closid == ~0) + return -ENOSPC; + + return cleanest_closid; +} + +/* + * For MPAM the RMID value is not unique, and has to be considered with + * the CLOSID. The (CLOSID, RMID) pair is allocated on all domains, which + * allows all domains to be managed by a single free list. + * Each domain also has a rmid_busy_llc to reduce the work of the limbo handler. + */ +int alloc_rmid(u32 closid) +{ + struct rmid_entry *entry; + + lockdep_assert_held(&rdtgroup_mutex); + + entry = resctrl_find_free_rmid(closid); + if (IS_ERR(entry)) + return PTR_ERR(entry); + + list_del(&entry->list); + return entry->rmid; +} + +static void add_rmid_to_limbo(struct rmid_entry *entry) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + struct rdt_mon_domain *d; + u32 idx; + + lockdep_assert_held(&rdtgroup_mutex); + + /* Walking r->domains, ensure it can't race with cpuhp */ + lockdep_assert_cpus_held(); + + idx = resctrl_arch_rmid_idx_encode(entry->closid, entry->rmid); + + entry->busy = 0; + list_for_each_entry(d, &r->mon_domains, hdr.list) { + /* + * For the first limbo RMID in the domain, + * setup up the limbo worker. + */ + if (!has_busy_rmid(d)) + cqm_setup_limbo_handler(d, CQM_LIMBOCHECK_INTERVAL, + RESCTRL_PICK_ANY_CPU); + set_bit(idx, d->rmid_busy_llc); + entry->busy++; + } + + rmid_limbo_count++; + if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) + closid_num_dirty_rmid[entry->closid]++; +} + +void free_rmid(u32 closid, u32 rmid) +{ + u32 idx = resctrl_arch_rmid_idx_encode(closid, rmid); + struct rmid_entry *entry; + + lockdep_assert_held(&rdtgroup_mutex); + + /* + * Do not allow the default rmid to be free'd. Comparing by index + * allows architectures that ignore the closid parameter to avoid an + * unnecessary check. + */ + if (!resctrl_arch_mon_capable() || + idx == resctrl_arch_rmid_idx_encode(RESCTRL_RESERVED_CLOSID, + RESCTRL_RESERVED_RMID)) + return; + + entry = __rmid_entry(idx); + + if (resctrl_is_mon_event_enabled(QOS_L3_OCCUP_EVENT_ID)) + add_rmid_to_limbo(entry); + else + list_add_tail(&entry->list, &rmid_free_lru); +} + +static struct mbm_state *get_mbm_state(struct rdt_mon_domain *d, u32 closid, + u32 rmid, enum resctrl_event_id evtid) +{ + u32 idx = resctrl_arch_rmid_idx_encode(closid, rmid); + struct mbm_state *state; + + if (!resctrl_is_mbm_event(evtid)) + return NULL; + + state = d->mbm_states[MBM_STATE_IDX(evtid)]; + + return state ? &state[idx] : NULL; +} + +/* + * mbm_cntr_get() - Return the counter ID for the matching @evtid and @rdtgrp. + * + * Return: + * Valid counter ID on success, or -ENOENT on failure. + */ +static int mbm_cntr_get(struct rdt_resource *r, struct rdt_mon_domain *d, + struct rdtgroup *rdtgrp, enum resctrl_event_id evtid) +{ + int cntr_id; + + if (!r->mon.mbm_cntr_assignable) + return -ENOENT; + + if (!resctrl_is_mbm_event(evtid)) + return -ENOENT; + + for (cntr_id = 0; cntr_id < r->mon.num_mbm_cntrs; cntr_id++) { + if (d->cntr_cfg[cntr_id].rdtgrp == rdtgrp && + d->cntr_cfg[cntr_id].evtid == evtid) + return cntr_id; + } + + return -ENOENT; +} + +/* + * mbm_cntr_alloc() - Initialize and return a new counter ID in the domain @d. + * Caller must ensure that the specified event is not assigned already. + * + * Return: + * Valid counter ID on success, or -ENOSPC on failure. + */ +static int mbm_cntr_alloc(struct rdt_resource *r, struct rdt_mon_domain *d, + struct rdtgroup *rdtgrp, enum resctrl_event_id evtid) +{ + int cntr_id; + + for (cntr_id = 0; cntr_id < r->mon.num_mbm_cntrs; cntr_id++) { + if (!d->cntr_cfg[cntr_id].rdtgrp) { + d->cntr_cfg[cntr_id].rdtgrp = rdtgrp; + d->cntr_cfg[cntr_id].evtid = evtid; + return cntr_id; + } + } + + return -ENOSPC; +} + +/* + * mbm_cntr_free() - Clear the counter ID configuration details in the domain @d. + */ +static void mbm_cntr_free(struct rdt_mon_domain *d, int cntr_id) +{ + memset(&d->cntr_cfg[cntr_id], 0, sizeof(*d->cntr_cfg)); +} + +static int __mon_event_count(struct rdtgroup *rdtgrp, struct rmid_read *rr) +{ + int cpu = smp_processor_id(); + u32 closid = rdtgrp->closid; + u32 rmid = rdtgrp->mon.rmid; + struct rdt_mon_domain *d; + int cntr_id = -ENOENT; + struct mbm_state *m; + int err, ret; + u64 tval = 0; + + if (rr->is_mbm_cntr) { + cntr_id = mbm_cntr_get(rr->r, rr->d, rdtgrp, rr->evtid); + if (cntr_id < 0) { + rr->err = -ENOENT; + return -EINVAL; + } + } + + if (rr->first) { + if (rr->is_mbm_cntr) + resctrl_arch_reset_cntr(rr->r, rr->d, closid, rmid, cntr_id, rr->evtid); + else + resctrl_arch_reset_rmid(rr->r, rr->d, closid, rmid, rr->evtid); + m = get_mbm_state(rr->d, closid, rmid, rr->evtid); + if (m) + memset(m, 0, sizeof(struct mbm_state)); + return 0; + } + + if (rr->d) { + /* Reading a single domain, must be on a CPU in that domain. */ + if (!cpumask_test_cpu(cpu, &rr->d->hdr.cpu_mask)) + return -EINVAL; + if (rr->is_mbm_cntr) + rr->err = resctrl_arch_cntr_read(rr->r, rr->d, closid, rmid, cntr_id, + rr->evtid, &tval); + else + rr->err = resctrl_arch_rmid_read(rr->r, rr->d, closid, rmid, + rr->evtid, &tval, rr->arch_mon_ctx); + if (rr->err) + return rr->err; + + rr->val += tval; + + return 0; + } + + /* Summing domains that share a cache, must be on a CPU for that cache. */ + if (!cpumask_test_cpu(cpu, &rr->ci->shared_cpu_map)) + return -EINVAL; + + /* + * Legacy files must report the sum of an event across all + * domains that share the same L3 cache instance. + * Report success if a read from any domain succeeds, -EINVAL + * (translated to "Unavailable" for user space) if reading from + * all domains fail for any reason. + */ + ret = -EINVAL; + list_for_each_entry(d, &rr->r->mon_domains, hdr.list) { + if (d->ci_id != rr->ci->id) + continue; + if (rr->is_mbm_cntr) + err = resctrl_arch_cntr_read(rr->r, d, closid, rmid, cntr_id, + rr->evtid, &tval); + else + err = resctrl_arch_rmid_read(rr->r, d, closid, rmid, + rr->evtid, &tval, rr->arch_mon_ctx); + if (!err) { + rr->val += tval; + ret = 0; + } + } + + if (ret) + rr->err = ret; + + return ret; +} + +/* + * mbm_bw_count() - Update bw count from values previously read by + * __mon_event_count(). + * @rdtgrp: resctrl group associated with the CLOSID and RMID to identify + * the cached mbm_state. + * @rr: The struct rmid_read populated by __mon_event_count(). + * + * Supporting function to calculate the memory bandwidth + * and delta bandwidth in MBps. The chunks value previously read by + * __mon_event_count() is compared with the chunks value from the previous + * invocation. This must be called once per second to maintain values in MBps. + */ +static void mbm_bw_count(struct rdtgroup *rdtgrp, struct rmid_read *rr) +{ + u64 cur_bw, bytes, cur_bytes; + u32 closid = rdtgrp->closid; + u32 rmid = rdtgrp->mon.rmid; + struct mbm_state *m; + + m = get_mbm_state(rr->d, closid, rmid, rr->evtid); + if (WARN_ON_ONCE(!m)) + return; + + cur_bytes = rr->val; + bytes = cur_bytes - m->prev_bw_bytes; + m->prev_bw_bytes = cur_bytes; + + cur_bw = bytes / SZ_1M; + + m->prev_bw = cur_bw; +} + +/* + * This is scheduled by mon_event_read() to read the CQM/MBM counters + * on a domain. + */ +void mon_event_count(void *info) +{ + struct rdtgroup *rdtgrp, *entry; + struct rmid_read *rr = info; + struct list_head *head; + int ret; + + rdtgrp = rr->rgrp; + + ret = __mon_event_count(rdtgrp, rr); + + /* + * For Ctrl groups read data from child monitor groups and + * add them together. Count events which are read successfully. + * Discard the rmid_read's reporting errors. + */ + head = &rdtgrp->mon.crdtgrp_list; + + if (rdtgrp->type == RDTCTRL_GROUP) { + list_for_each_entry(entry, head, mon.crdtgrp_list) { + if (__mon_event_count(entry, rr) == 0) + ret = 0; + } + } + + /* + * __mon_event_count() calls for newly created monitor groups may + * report -EINVAL/Unavailable if the monitor hasn't seen any traffic. + * Discard error if any of the monitor event reads succeeded. + */ + if (ret == 0) + rr->err = 0; +} + +static struct rdt_ctrl_domain *get_ctrl_domain_from_cpu(int cpu, + struct rdt_resource *r) +{ + struct rdt_ctrl_domain *d; + + lockdep_assert_cpus_held(); + + list_for_each_entry(d, &r->ctrl_domains, hdr.list) { + /* Find the domain that contains this CPU */ + if (cpumask_test_cpu(cpu, &d->hdr.cpu_mask)) + return d; + } + + return NULL; +} + +/* + * Feedback loop for MBA software controller (mba_sc) + * + * mba_sc is a feedback loop where we periodically read MBM counters and + * adjust the bandwidth percentage values via the IA32_MBA_THRTL_MSRs so + * that: + * + * current bandwidth(cur_bw) < user specified bandwidth(user_bw) + * + * This uses the MBM counters to measure the bandwidth and MBA throttle + * MSRs to control the bandwidth for a particular rdtgrp. It builds on the + * fact that resctrl rdtgroups have both monitoring and control. + * + * The frequency of the checks is 1s and we just tag along the MBM overflow + * timer. Having 1s interval makes the calculation of bandwidth simpler. + * + * Although MBA's goal is to restrict the bandwidth to a maximum, there may + * be a need to increase the bandwidth to avoid unnecessarily restricting + * the L2 <-> L3 traffic. + * + * Since MBA controls the L2 external bandwidth where as MBM measures the + * L3 external bandwidth the following sequence could lead to such a + * situation. + * + * Consider an rdtgroup which had high L3 <-> memory traffic in initial + * phases -> mba_sc kicks in and reduced bandwidth percentage values -> but + * after some time rdtgroup has mostly L2 <-> L3 traffic. + * + * In this case we may restrict the rdtgroup's L2 <-> L3 traffic as its + * throttle MSRs already have low percentage values. To avoid + * unnecessarily restricting such rdtgroups, we also increase the bandwidth. + */ +static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_mon_domain *dom_mbm) +{ + u32 closid, rmid, cur_msr_val, new_msr_val; + struct mbm_state *pmbm_data, *cmbm_data; + struct rdt_ctrl_domain *dom_mba; + enum resctrl_event_id evt_id; + struct rdt_resource *r_mba; + struct list_head *head; + struct rdtgroup *entry; + u32 cur_bw, user_bw; + + r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA); + evt_id = rgrp->mba_mbps_event; + + closid = rgrp->closid; + rmid = rgrp->mon.rmid; + pmbm_data = get_mbm_state(dom_mbm, closid, rmid, evt_id); + if (WARN_ON_ONCE(!pmbm_data)) + return; + + dom_mba = get_ctrl_domain_from_cpu(smp_processor_id(), r_mba); + if (!dom_mba) { + pr_warn_once("Failure to get domain for MBA update\n"); + return; + } + + cur_bw = pmbm_data->prev_bw; + user_bw = dom_mba->mbps_val[closid]; + + /* MBA resource doesn't support CDP */ + cur_msr_val = resctrl_arch_get_config(r_mba, dom_mba, closid, CDP_NONE); + + /* + * For Ctrl groups read data from child monitor groups. + */ + head = &rgrp->mon.crdtgrp_list; + list_for_each_entry(entry, head, mon.crdtgrp_list) { + cmbm_data = get_mbm_state(dom_mbm, entry->closid, entry->mon.rmid, evt_id); + if (WARN_ON_ONCE(!cmbm_data)) + return; + cur_bw += cmbm_data->prev_bw; + } + + /* + * Scale up/down the bandwidth linearly for the ctrl group. The + * bandwidth step is the bandwidth granularity specified by the + * hardware. + * Always increase throttling if current bandwidth is above the + * target set by user. + * But avoid thrashing up and down on every poll by checking + * whether a decrease in throttling is likely to push the group + * back over target. E.g. if currently throttling to 30% of bandwidth + * on a system with 10% granularity steps, check whether moving to + * 40% would go past the limit by multiplying current bandwidth by + * "(30 + 10) / 30". + */ + if (cur_msr_val > r_mba->membw.min_bw && user_bw < cur_bw) { + new_msr_val = cur_msr_val - r_mba->membw.bw_gran; + } else if (cur_msr_val < MAX_MBA_BW && + (user_bw > (cur_bw * (cur_msr_val + r_mba->membw.min_bw) / cur_msr_val))) { + new_msr_val = cur_msr_val + r_mba->membw.bw_gran; + } else { + return; + } + + resctrl_arch_update_one(r_mba, dom_mba, closid, CDP_NONE, new_msr_val); +} + +static void mbm_update_one_event(struct rdt_resource *r, struct rdt_mon_domain *d, + struct rdtgroup *rdtgrp, enum resctrl_event_id evtid) +{ + struct rmid_read rr = {0}; + + rr.r = r; + rr.d = d; + rr.evtid = evtid; + if (resctrl_arch_mbm_cntr_assign_enabled(r)) { + rr.is_mbm_cntr = true; + } else { + rr.arch_mon_ctx = resctrl_arch_mon_ctx_alloc(rr.r, rr.evtid); + if (IS_ERR(rr.arch_mon_ctx)) { + pr_warn_ratelimited("Failed to allocate monitor context: %ld", + PTR_ERR(rr.arch_mon_ctx)); + return; + } + } + + __mon_event_count(rdtgrp, &rr); + + /* + * If the software controller is enabled, compute the + * bandwidth for this event id. + */ + if (is_mba_sc(NULL)) + mbm_bw_count(rdtgrp, &rr); + + if (rr.arch_mon_ctx) + resctrl_arch_mon_ctx_free(rr.r, rr.evtid, rr.arch_mon_ctx); +} + +static void mbm_update(struct rdt_resource *r, struct rdt_mon_domain *d, + struct rdtgroup *rdtgrp) +{ + /* + * This is protected from concurrent reads from user as both + * the user and overflow handler hold the global mutex. + */ + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_TOTAL_EVENT_ID)) + mbm_update_one_event(r, d, rdtgrp, QOS_L3_MBM_TOTAL_EVENT_ID); + + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_LOCAL_EVENT_ID)) + mbm_update_one_event(r, d, rdtgrp, QOS_L3_MBM_LOCAL_EVENT_ID); +} + +/* + * Handler to scan the limbo list and move the RMIDs + * to free list whose occupancy < threshold_occupancy. + */ +void cqm_handle_limbo(struct work_struct *work) +{ + unsigned long delay = msecs_to_jiffies(CQM_LIMBOCHECK_INTERVAL); + struct rdt_mon_domain *d; + + cpus_read_lock(); + mutex_lock(&rdtgroup_mutex); + + d = container_of(work, struct rdt_mon_domain, cqm_limbo.work); + + __check_limbo(d, false); + + if (has_busy_rmid(d)) { + d->cqm_work_cpu = cpumask_any_housekeeping(&d->hdr.cpu_mask, + RESCTRL_PICK_ANY_CPU); + schedule_delayed_work_on(d->cqm_work_cpu, &d->cqm_limbo, + delay); + } + + mutex_unlock(&rdtgroup_mutex); + cpus_read_unlock(); +} + +/** + * cqm_setup_limbo_handler() - Schedule the limbo handler to run for this + * domain. + * @dom: The domain the limbo handler should run for. + * @delay_ms: How far in the future the handler should run. + * @exclude_cpu: Which CPU the handler should not run on, + * RESCTRL_PICK_ANY_CPU to pick any CPU. + */ +void cqm_setup_limbo_handler(struct rdt_mon_domain *dom, unsigned long delay_ms, + int exclude_cpu) +{ + unsigned long delay = msecs_to_jiffies(delay_ms); + int cpu; + + cpu = cpumask_any_housekeeping(&dom->hdr.cpu_mask, exclude_cpu); + dom->cqm_work_cpu = cpu; + + if (cpu < nr_cpu_ids) + schedule_delayed_work_on(cpu, &dom->cqm_limbo, delay); +} + +void mbm_handle_overflow(struct work_struct *work) +{ + unsigned long delay = msecs_to_jiffies(MBM_OVERFLOW_INTERVAL); + struct rdtgroup *prgrp, *crgrp; + struct rdt_mon_domain *d; + struct list_head *head; + struct rdt_resource *r; + + cpus_read_lock(); + mutex_lock(&rdtgroup_mutex); + + /* + * If the filesystem has been unmounted this work no longer needs to + * run. + */ + if (!resctrl_mounted || !resctrl_arch_mon_capable()) + goto out_unlock; + + r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + d = container_of(work, struct rdt_mon_domain, mbm_over.work); + + list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) { + mbm_update(r, d, prgrp); + + head = &prgrp->mon.crdtgrp_list; + list_for_each_entry(crgrp, head, mon.crdtgrp_list) + mbm_update(r, d, crgrp); + + if (is_mba_sc(NULL)) + update_mba_bw(prgrp, d); + } + + /* + * Re-check for housekeeping CPUs. This allows the overflow handler to + * move off a nohz_full CPU quickly. + */ + d->mbm_work_cpu = cpumask_any_housekeeping(&d->hdr.cpu_mask, + RESCTRL_PICK_ANY_CPU); + schedule_delayed_work_on(d->mbm_work_cpu, &d->mbm_over, delay); + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + cpus_read_unlock(); +} + +/** + * mbm_setup_overflow_handler() - Schedule the overflow handler to run for this + * domain. + * @dom: The domain the overflow handler should run for. + * @delay_ms: How far in the future the handler should run. + * @exclude_cpu: Which CPU the handler should not run on, + * RESCTRL_PICK_ANY_CPU to pick any CPU. + */ +void mbm_setup_overflow_handler(struct rdt_mon_domain *dom, unsigned long delay_ms, + int exclude_cpu) +{ + unsigned long delay = msecs_to_jiffies(delay_ms); + int cpu; + + /* + * When a domain comes online there is no guarantee the filesystem is + * mounted. If not, there is no need to catch counter overflow. + */ + if (!resctrl_mounted || !resctrl_arch_mon_capable()) + return; + cpu = cpumask_any_housekeeping(&dom->hdr.cpu_mask, exclude_cpu); + dom->mbm_work_cpu = cpu; + + if (cpu < nr_cpu_ids) + schedule_delayed_work_on(cpu, &dom->mbm_over, delay); +} + +static int dom_data_init(struct rdt_resource *r) +{ + u32 idx_limit = resctrl_arch_system_num_rmid_idx(); + u32 num_closid = resctrl_arch_get_num_closid(r); + struct rmid_entry *entry = NULL; + int err = 0, i; + u32 idx; + + mutex_lock(&rdtgroup_mutex); + if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) { + u32 *tmp; + + /* + * If the architecture hasn't provided a sanitised value here, + * this may result in larger arrays than necessary. Resctrl will + * use a smaller system wide value based on the resources in + * use. + */ + tmp = kcalloc(num_closid, sizeof(*tmp), GFP_KERNEL); + if (!tmp) { + err = -ENOMEM; + goto out_unlock; + } + + closid_num_dirty_rmid = tmp; + } + + rmid_ptrs = kcalloc(idx_limit, sizeof(struct rmid_entry), GFP_KERNEL); + if (!rmid_ptrs) { + if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) { + kfree(closid_num_dirty_rmid); + closid_num_dirty_rmid = NULL; + } + err = -ENOMEM; + goto out_unlock; + } + + for (i = 0; i < idx_limit; i++) { + entry = &rmid_ptrs[i]; + INIT_LIST_HEAD(&entry->list); + + resctrl_arch_rmid_idx_decode(i, &entry->closid, &entry->rmid); + list_add_tail(&entry->list, &rmid_free_lru); + } + + /* + * RESCTRL_RESERVED_CLOSID and RESCTRL_RESERVED_RMID are special and + * are always allocated. These are used for the rdtgroup_default + * control group, which will be setup later in resctrl_init(). + */ + idx = resctrl_arch_rmid_idx_encode(RESCTRL_RESERVED_CLOSID, + RESCTRL_RESERVED_RMID); + entry = __rmid_entry(idx); + list_del(&entry->list); + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + + return err; +} + +static void dom_data_exit(struct rdt_resource *r) +{ + mutex_lock(&rdtgroup_mutex); + + if (!r->mon_capable) + goto out_unlock; + + if (IS_ENABLED(CONFIG_RESCTRL_RMID_DEPENDS_ON_CLOSID)) { + kfree(closid_num_dirty_rmid); + closid_num_dirty_rmid = NULL; + } + + kfree(rmid_ptrs); + rmid_ptrs = NULL; + +out_unlock: + mutex_unlock(&rdtgroup_mutex); +} + +/* + * All available events. Architecture code marks the ones that + * are supported by a system using resctrl_enable_mon_event() + * to set .enabled. + */ +struct mon_evt mon_event_all[QOS_NUM_EVENTS] = { + [QOS_L3_OCCUP_EVENT_ID] = { + .name = "llc_occupancy", + .evtid = QOS_L3_OCCUP_EVENT_ID, + .rid = RDT_RESOURCE_L3, + }, + [QOS_L3_MBM_TOTAL_EVENT_ID] = { + .name = "mbm_total_bytes", + .evtid = QOS_L3_MBM_TOTAL_EVENT_ID, + .rid = RDT_RESOURCE_L3, + }, + [QOS_L3_MBM_LOCAL_EVENT_ID] = { + .name = "mbm_local_bytes", + .evtid = QOS_L3_MBM_LOCAL_EVENT_ID, + .rid = RDT_RESOURCE_L3, + }, +}; + +void resctrl_enable_mon_event(enum resctrl_event_id eventid) +{ + if (WARN_ON_ONCE(eventid < QOS_FIRST_EVENT || eventid >= QOS_NUM_EVENTS)) + return; + if (mon_event_all[eventid].enabled) { + pr_warn("Duplicate enable for event %d\n", eventid); + return; + } + + mon_event_all[eventid].enabled = true; +} + +bool resctrl_is_mon_event_enabled(enum resctrl_event_id eventid) +{ + return eventid >= QOS_FIRST_EVENT && eventid < QOS_NUM_EVENTS && + mon_event_all[eventid].enabled; +} + +u32 resctrl_get_mon_evt_cfg(enum resctrl_event_id evtid) +{ + return mon_event_all[evtid].evt_cfg; +} + +/** + * struct mbm_transaction - Memory transaction an MBM event can be configured with. + * @name: Name of memory transaction (read, write ...). + * @val: The bit (eg. READS_TO_LOCAL_MEM or READS_TO_REMOTE_MEM) used to + * represent the memory transaction within an event's configuration. + */ +struct mbm_transaction { + char name[32]; + u32 val; +}; + +/* Decoded values for each type of memory transaction. */ +static struct mbm_transaction mbm_transactions[NUM_MBM_TRANSACTIONS] = { + {"local_reads", READS_TO_LOCAL_MEM}, + {"remote_reads", READS_TO_REMOTE_MEM}, + {"local_non_temporal_writes", NON_TEMP_WRITE_TO_LOCAL_MEM}, + {"remote_non_temporal_writes", NON_TEMP_WRITE_TO_REMOTE_MEM}, + {"local_reads_slow_memory", READS_TO_LOCAL_S_MEM}, + {"remote_reads_slow_memory", READS_TO_REMOTE_S_MEM}, + {"dirty_victim_writes_all", DIRTY_VICTIMS_TO_ALL_MEM}, +}; + +int event_filter_show(struct kernfs_open_file *of, struct seq_file *seq, void *v) +{ + struct mon_evt *mevt = rdt_kn_parent_priv(of->kn); + struct rdt_resource *r; + bool sep = false; + int ret = 0, i; + + mutex_lock(&rdtgroup_mutex); + rdt_last_cmd_clear(); + + r = resctrl_arch_get_resource(mevt->rid); + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) { + rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n"); + ret = -EINVAL; + goto out_unlock; + } + + for (i = 0; i < NUM_MBM_TRANSACTIONS; i++) { + if (mevt->evt_cfg & mbm_transactions[i].val) { + if (sep) + seq_putc(seq, ','); + seq_printf(seq, "%s", mbm_transactions[i].name); + sep = true; + } + } + seq_putc(seq, '\n'); + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + + return ret; +} + +int resctrl_mbm_assign_on_mkdir_show(struct kernfs_open_file *of, struct seq_file *s, + void *v) +{ + struct rdt_resource *r = rdt_kn_parent_priv(of->kn); + int ret = 0; + + mutex_lock(&rdtgroup_mutex); + rdt_last_cmd_clear(); + + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) { + rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n"); + ret = -EINVAL; + goto out_unlock; + } + + seq_printf(s, "%u\n", r->mon.mbm_assign_on_mkdir); + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + + return ret; +} + +ssize_t resctrl_mbm_assign_on_mkdir_write(struct kernfs_open_file *of, char *buf, + size_t nbytes, loff_t off) +{ + struct rdt_resource *r = rdt_kn_parent_priv(of->kn); + bool value; + int ret; + + ret = kstrtobool(buf, &value); + if (ret) + return ret; + + mutex_lock(&rdtgroup_mutex); + rdt_last_cmd_clear(); + + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) { + rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n"); + ret = -EINVAL; + goto out_unlock; + } + + r->mon.mbm_assign_on_mkdir = value; + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + + return ret ?: nbytes; +} + +/* + * mbm_cntr_free_all() - Clear all the counter ID configuration details in the + * domain @d. Called when mbm_assign_mode is changed. + */ +static void mbm_cntr_free_all(struct rdt_resource *r, struct rdt_mon_domain *d) +{ + memset(d->cntr_cfg, 0, sizeof(*d->cntr_cfg) * r->mon.num_mbm_cntrs); +} + +/* + * resctrl_reset_rmid_all() - Reset all non-architecture states for all the + * supported RMIDs. + */ +static void resctrl_reset_rmid_all(struct rdt_resource *r, struct rdt_mon_domain *d) +{ + u32 idx_limit = resctrl_arch_system_num_rmid_idx(); + enum resctrl_event_id evt; + int idx; + + for_each_mbm_event_id(evt) { + if (!resctrl_is_mon_event_enabled(evt)) + continue; + idx = MBM_STATE_IDX(evt); + memset(d->mbm_states[idx], 0, sizeof(*d->mbm_states[0]) * idx_limit); + } +} + +/* + * rdtgroup_assign_cntr() - Assign/unassign the counter ID for the event, RMID + * pair in the domain. + * + * Assign the counter if @assign is true else unassign the counter. Reset the + * associated non-architectural state. + */ +static void rdtgroup_assign_cntr(struct rdt_resource *r, struct rdt_mon_domain *d, + enum resctrl_event_id evtid, u32 rmid, u32 closid, + u32 cntr_id, bool assign) +{ + struct mbm_state *m; + + resctrl_arch_config_cntr(r, d, evtid, rmid, closid, cntr_id, assign); + + m = get_mbm_state(d, closid, rmid, evtid); + if (m) + memset(m, 0, sizeof(*m)); +} + +/* + * rdtgroup_alloc_assign_cntr() - Allocate a counter ID and assign it to the event + * pointed to by @mevt and the resctrl group @rdtgrp within the domain @d. + * + * Return: + * 0 on success, < 0 on failure. + */ +static int rdtgroup_alloc_assign_cntr(struct rdt_resource *r, struct rdt_mon_domain *d, + struct rdtgroup *rdtgrp, struct mon_evt *mevt) +{ + int cntr_id; + + /* No action required if the counter is assigned already. */ + cntr_id = mbm_cntr_get(r, d, rdtgrp, mevt->evtid); + if (cntr_id >= 0) + return 0; + + cntr_id = mbm_cntr_alloc(r, d, rdtgrp, mevt->evtid); + if (cntr_id < 0) { + rdt_last_cmd_printf("Failed to allocate counter for %s in domain %d\n", + mevt->name, d->hdr.id); + return cntr_id; + } + + rdtgroup_assign_cntr(r, d, mevt->evtid, rdtgrp->mon.rmid, rdtgrp->closid, cntr_id, true); + + return 0; +} + +/* + * rdtgroup_assign_cntr_event() - Assign a hardware counter for the event in + * @mevt to the resctrl group @rdtgrp. Assign counters to all domains if @d is + * NULL; otherwise, assign the counter to the specified domain @d. + * + * If all counters in a domain are already in use, rdtgroup_alloc_assign_cntr() + * will fail. The assignment process will abort at the first failure encountered + * during domain traversal, which may result in the event being only partially + * assigned. + * + * Return: + * 0 on success, < 0 on failure. + */ +static int rdtgroup_assign_cntr_event(struct rdt_mon_domain *d, struct rdtgroup *rdtgrp, + struct mon_evt *mevt) +{ + struct rdt_resource *r = resctrl_arch_get_resource(mevt->rid); + int ret = 0; + + if (!d) { + list_for_each_entry(d, &r->mon_domains, hdr.list) { + ret = rdtgroup_alloc_assign_cntr(r, d, rdtgrp, mevt); + if (ret) + return ret; + } + } else { + ret = rdtgroup_alloc_assign_cntr(r, d, rdtgrp, mevt); + } + + return ret; +} + +/* + * rdtgroup_assign_cntrs() - Assign counters to MBM events. Called when + * a new group is created. + * + * Each group can accommodate two counters per domain: one for the total + * event and one for the local event. Assignments may fail due to the limited + * number of counters. However, it is not necessary to fail the group creation + * and thus no failure is returned. Users have the option to modify the + * counter assignments after the group has been created. + */ +void rdtgroup_assign_cntrs(struct rdtgroup *rdtgrp) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + + if (!r->mon_capable || !resctrl_arch_mbm_cntr_assign_enabled(r) || + !r->mon.mbm_assign_on_mkdir) + return; + + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_TOTAL_EVENT_ID)) + rdtgroup_assign_cntr_event(NULL, rdtgrp, + &mon_event_all[QOS_L3_MBM_TOTAL_EVENT_ID]); + + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_LOCAL_EVENT_ID)) + rdtgroup_assign_cntr_event(NULL, rdtgrp, + &mon_event_all[QOS_L3_MBM_LOCAL_EVENT_ID]); +} + +/* + * rdtgroup_free_unassign_cntr() - Unassign and reset the counter ID configuration + * for the event pointed to by @mevt within the domain @d and resctrl group @rdtgrp. + */ +static void rdtgroup_free_unassign_cntr(struct rdt_resource *r, struct rdt_mon_domain *d, + struct rdtgroup *rdtgrp, struct mon_evt *mevt) +{ + int cntr_id; + + cntr_id = mbm_cntr_get(r, d, rdtgrp, mevt->evtid); + + /* If there is no cntr_id assigned, nothing to do */ + if (cntr_id < 0) + return; + + rdtgroup_assign_cntr(r, d, mevt->evtid, rdtgrp->mon.rmid, rdtgrp->closid, cntr_id, false); + + mbm_cntr_free(d, cntr_id); +} + +/* + * rdtgroup_unassign_cntr_event() - Unassign a hardware counter associated with + * the event structure @mevt from the domain @d and the group @rdtgrp. Unassign + * the counters from all the domains if @d is NULL else unassign from @d. + */ +static void rdtgroup_unassign_cntr_event(struct rdt_mon_domain *d, struct rdtgroup *rdtgrp, + struct mon_evt *mevt) +{ + struct rdt_resource *r = resctrl_arch_get_resource(mevt->rid); + + if (!d) { + list_for_each_entry(d, &r->mon_domains, hdr.list) + rdtgroup_free_unassign_cntr(r, d, rdtgrp, mevt); + } else { + rdtgroup_free_unassign_cntr(r, d, rdtgrp, mevt); + } +} + +/* + * rdtgroup_unassign_cntrs() - Unassign the counters associated with MBM events. + * Called when a group is deleted. + */ +void rdtgroup_unassign_cntrs(struct rdtgroup *rdtgrp) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + + if (!r->mon_capable || !resctrl_arch_mbm_cntr_assign_enabled(r)) + return; + + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_TOTAL_EVENT_ID)) + rdtgroup_unassign_cntr_event(NULL, rdtgrp, + &mon_event_all[QOS_L3_MBM_TOTAL_EVENT_ID]); + + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_LOCAL_EVENT_ID)) + rdtgroup_unassign_cntr_event(NULL, rdtgrp, + &mon_event_all[QOS_L3_MBM_LOCAL_EVENT_ID]); +} + +static int resctrl_parse_mem_transactions(char *tok, u32 *val) +{ + u32 temp_val = 0; + char *evt_str; + bool found; + int i; + +next_config: + if (!tok || tok[0] == '\0') { + *val = temp_val; + return 0; + } + + /* Start processing the strings for each memory transaction type */ + evt_str = strim(strsep(&tok, ",")); + found = false; + for (i = 0; i < NUM_MBM_TRANSACTIONS; i++) { + if (!strcmp(mbm_transactions[i].name, evt_str)) { + temp_val |= mbm_transactions[i].val; + found = true; + break; + } + } + + if (!found) { + rdt_last_cmd_printf("Invalid memory transaction type %s\n", evt_str); + return -EINVAL; + } + + goto next_config; +} + +/* + * rdtgroup_update_cntr_event - Update the counter assignments for the event + * in a group. + * @r: Resource to which update needs to be done. + * @rdtgrp: Resctrl group. + * @evtid: MBM monitor event. + */ +static void rdtgroup_update_cntr_event(struct rdt_resource *r, struct rdtgroup *rdtgrp, + enum resctrl_event_id evtid) +{ + struct rdt_mon_domain *d; + int cntr_id; + + list_for_each_entry(d, &r->mon_domains, hdr.list) { + cntr_id = mbm_cntr_get(r, d, rdtgrp, evtid); + if (cntr_id >= 0) + rdtgroup_assign_cntr(r, d, evtid, rdtgrp->mon.rmid, + rdtgrp->closid, cntr_id, true); + } +} + +/* + * resctrl_update_cntr_allrdtgrp - Update the counter assignments for the event + * for all the groups. + * @mevt MBM Monitor event. + */ +static void resctrl_update_cntr_allrdtgrp(struct mon_evt *mevt) +{ + struct rdt_resource *r = resctrl_arch_get_resource(mevt->rid); + struct rdtgroup *prgrp, *crgrp; + + /* + * Find all the groups where the event is assigned and update the + * configuration of existing assignments. + */ + list_for_each_entry(prgrp, &rdt_all_groups, rdtgroup_list) { + rdtgroup_update_cntr_event(r, prgrp, mevt->evtid); + + list_for_each_entry(crgrp, &prgrp->mon.crdtgrp_list, mon.crdtgrp_list) + rdtgroup_update_cntr_event(r, crgrp, mevt->evtid); + } +} + +ssize_t event_filter_write(struct kernfs_open_file *of, char *buf, size_t nbytes, + loff_t off) +{ + struct mon_evt *mevt = rdt_kn_parent_priv(of->kn); + struct rdt_resource *r; + u32 evt_cfg = 0; + int ret = 0; + + /* Valid input requires a trailing newline */ + if (nbytes == 0 || buf[nbytes - 1] != '\n') + return -EINVAL; + + buf[nbytes - 1] = '\0'; + + cpus_read_lock(); + mutex_lock(&rdtgroup_mutex); + + rdt_last_cmd_clear(); + + r = resctrl_arch_get_resource(mevt->rid); + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) { + rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n"); + ret = -EINVAL; + goto out_unlock; + } + + ret = resctrl_parse_mem_transactions(buf, &evt_cfg); + if (!ret && mevt->evt_cfg != evt_cfg) { + mevt->evt_cfg = evt_cfg; + resctrl_update_cntr_allrdtgrp(mevt); + } + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + cpus_read_unlock(); + + return ret ?: nbytes; +} + +int resctrl_mbm_assign_mode_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct rdt_resource *r = rdt_kn_parent_priv(of->kn); + bool enabled; + + mutex_lock(&rdtgroup_mutex); + enabled = resctrl_arch_mbm_cntr_assign_enabled(r); + + if (r->mon.mbm_cntr_assignable) { + if (enabled) + seq_puts(s, "[mbm_event]\n"); + else + seq_puts(s, "[default]\n"); + + if (!IS_ENABLED(CONFIG_RESCTRL_ASSIGN_FIXED)) { + if (enabled) + seq_puts(s, "default\n"); + else + seq_puts(s, "mbm_event\n"); + } + } else { + seq_puts(s, "[default]\n"); + } + + mutex_unlock(&rdtgroup_mutex); + + return 0; +} + +ssize_t resctrl_mbm_assign_mode_write(struct kernfs_open_file *of, char *buf, + size_t nbytes, loff_t off) +{ + struct rdt_resource *r = rdt_kn_parent_priv(of->kn); + struct rdt_mon_domain *d; + int ret = 0; + bool enable; + + /* Valid input requires a trailing newline */ + if (nbytes == 0 || buf[nbytes - 1] != '\n') + return -EINVAL; + + buf[nbytes - 1] = '\0'; + + cpus_read_lock(); + mutex_lock(&rdtgroup_mutex); + + rdt_last_cmd_clear(); + + if (!strcmp(buf, "default")) { + enable = 0; + } else if (!strcmp(buf, "mbm_event")) { + if (r->mon.mbm_cntr_assignable) { + enable = 1; + } else { + ret = -EINVAL; + rdt_last_cmd_puts("mbm_event mode is not supported\n"); + goto out_unlock; + } + } else { + ret = -EINVAL; + rdt_last_cmd_puts("Unsupported assign mode\n"); + goto out_unlock; + } + + if (enable != resctrl_arch_mbm_cntr_assign_enabled(r)) { + ret = resctrl_arch_mbm_cntr_assign_set(r, enable); + if (ret) + goto out_unlock; + + /* Update the visibility of BMEC related files */ + resctrl_bmec_files_show(r, NULL, !enable); + + /* + * Initialize the default memory transaction values for + * total and local events. + */ + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_TOTAL_EVENT_ID)) + mon_event_all[QOS_L3_MBM_TOTAL_EVENT_ID].evt_cfg = r->mon.mbm_cfg_mask; + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_LOCAL_EVENT_ID)) + mon_event_all[QOS_L3_MBM_LOCAL_EVENT_ID].evt_cfg = r->mon.mbm_cfg_mask & + (READS_TO_LOCAL_MEM | + READS_TO_LOCAL_S_MEM | + NON_TEMP_WRITE_TO_LOCAL_MEM); + /* Enable auto assignment when switching to "mbm_event" mode */ + if (enable) + r->mon.mbm_assign_on_mkdir = true; + /* + * Reset all the non-achitectural RMID state and assignable counters. + */ + list_for_each_entry(d, &r->mon_domains, hdr.list) { + mbm_cntr_free_all(r, d); + resctrl_reset_rmid_all(r, d); + } + } + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + cpus_read_unlock(); + + return ret ?: nbytes; +} + +int resctrl_num_mbm_cntrs_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct rdt_resource *r = rdt_kn_parent_priv(of->kn); + struct rdt_mon_domain *dom; + bool sep = false; + + cpus_read_lock(); + mutex_lock(&rdtgroup_mutex); + + list_for_each_entry(dom, &r->mon_domains, hdr.list) { + if (sep) + seq_putc(s, ';'); + + seq_printf(s, "%d=%d", dom->hdr.id, r->mon.num_mbm_cntrs); + sep = true; + } + seq_putc(s, '\n'); + + mutex_unlock(&rdtgroup_mutex); + cpus_read_unlock(); + return 0; +} + +int resctrl_available_mbm_cntrs_show(struct kernfs_open_file *of, + struct seq_file *s, void *v) +{ + struct rdt_resource *r = rdt_kn_parent_priv(of->kn); + struct rdt_mon_domain *dom; + bool sep = false; + u32 cntrs, i; + int ret = 0; + + cpus_read_lock(); + mutex_lock(&rdtgroup_mutex); + + rdt_last_cmd_clear(); + + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) { + rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n"); + ret = -EINVAL; + goto out_unlock; + } + + list_for_each_entry(dom, &r->mon_domains, hdr.list) { + if (sep) + seq_putc(s, ';'); + + cntrs = 0; + for (i = 0; i < r->mon.num_mbm_cntrs; i++) { + if (!dom->cntr_cfg[i].rdtgrp) + cntrs++; + } + + seq_printf(s, "%d=%u", dom->hdr.id, cntrs); + sep = true; + } + seq_putc(s, '\n'); + +out_unlock: + mutex_unlock(&rdtgroup_mutex); + cpus_read_unlock(); + + return ret; +} + +int mbm_L3_assignments_show(struct kernfs_open_file *of, struct seq_file *s, void *v) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + struct rdt_mon_domain *d; + struct rdtgroup *rdtgrp; + struct mon_evt *mevt; + int ret = 0; + bool sep; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (!rdtgrp) { + ret = -ENOENT; + goto out_unlock; + } + + rdt_last_cmd_clear(); + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) { + rdt_last_cmd_puts("mbm_event counter assignment mode is not enabled\n"); + ret = -EINVAL; + goto out_unlock; + } + + for_each_mon_event(mevt) { + if (mevt->rid != r->rid || !mevt->enabled || !resctrl_is_mbm_event(mevt->evtid)) + continue; + + sep = false; + seq_printf(s, "%s:", mevt->name); + list_for_each_entry(d, &r->mon_domains, hdr.list) { + if (sep) + seq_putc(s, ';'); + + if (mbm_cntr_get(r, d, rdtgrp, mevt->evtid) < 0) + seq_printf(s, "%d=_", d->hdr.id); + else + seq_printf(s, "%d=e", d->hdr.id); + + sep = true; + } + seq_putc(s, '\n'); + } + +out_unlock: + rdtgroup_kn_unlock(of->kn); + + return ret; +} + +/* + * mbm_get_mon_event_by_name() - Return the mon_evt entry for the matching + * event name. + */ +static struct mon_evt *mbm_get_mon_event_by_name(struct rdt_resource *r, char *name) +{ + struct mon_evt *mevt; + + for_each_mon_event(mevt) { + if (mevt->rid == r->rid && mevt->enabled && + resctrl_is_mbm_event(mevt->evtid) && + !strcmp(mevt->name, name)) + return mevt; + } + + return NULL; +} + +static int rdtgroup_modify_assign_state(char *assign, struct rdt_mon_domain *d, + struct rdtgroup *rdtgrp, struct mon_evt *mevt) +{ + int ret = 0; + + if (!assign || strlen(assign) != 1) + return -EINVAL; + + switch (*assign) { + case 'e': + ret = rdtgroup_assign_cntr_event(d, rdtgrp, mevt); + break; + case '_': + rdtgroup_unassign_cntr_event(d, rdtgrp, mevt); + break; + default: + ret = -EINVAL; + break; + } + + return ret; +} + +static int resctrl_parse_mbm_assignment(struct rdt_resource *r, struct rdtgroup *rdtgrp, + char *event, char *tok) +{ + struct rdt_mon_domain *d; + unsigned long dom_id = 0; + char *dom_str, *id_str; + struct mon_evt *mevt; + int ret; + + mevt = mbm_get_mon_event_by_name(r, event); + if (!mevt) { + rdt_last_cmd_printf("Invalid event %s\n", event); + return -ENOENT; + } + +next: + if (!tok || tok[0] == '\0') + return 0; + + /* Start processing the strings for each domain */ + dom_str = strim(strsep(&tok, ";")); + + id_str = strsep(&dom_str, "="); + + /* Check for domain id '*' which means all domains */ + if (id_str && *id_str == '*') { + ret = rdtgroup_modify_assign_state(dom_str, NULL, rdtgrp, mevt); + if (ret) + rdt_last_cmd_printf("Assign operation '%s:*=%s' failed\n", + event, dom_str); + return ret; + } else if (!id_str || kstrtoul(id_str, 10, &dom_id)) { + rdt_last_cmd_puts("Missing domain id\n"); + return -EINVAL; + } + + /* Verify if the dom_id is valid */ + list_for_each_entry(d, &r->mon_domains, hdr.list) { + if (d->hdr.id == dom_id) { + ret = rdtgroup_modify_assign_state(dom_str, d, rdtgrp, mevt); + if (ret) { + rdt_last_cmd_printf("Assign operation '%s:%ld=%s' failed\n", + event, dom_id, dom_str); + return ret; + } + goto next; + } + } + + rdt_last_cmd_printf("Invalid domain id %ld\n", dom_id); + return -EINVAL; +} + +ssize_t mbm_L3_assignments_write(struct kernfs_open_file *of, char *buf, + size_t nbytes, loff_t off) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + struct rdtgroup *rdtgrp; + char *token, *event; + int ret = 0; + + /* Valid input requires a trailing newline */ + if (nbytes == 0 || buf[nbytes - 1] != '\n') + return -EINVAL; + + buf[nbytes - 1] = '\0'; + + rdtgrp = rdtgroup_kn_lock_live(of->kn); + if (!rdtgrp) { + rdtgroup_kn_unlock(of->kn); + return -ENOENT; + } + rdt_last_cmd_clear(); + + if (!resctrl_arch_mbm_cntr_assign_enabled(r)) { + rdt_last_cmd_puts("mbm_event mode is not enabled\n"); + rdtgroup_kn_unlock(of->kn); + return -EINVAL; + } + + while ((token = strsep(&buf, "\n")) != NULL) { + /* + * The write command follows the following format: + * "<Event>:<Domain ID>=<Assignment state>" + * Extract the event name first. + */ + event = strsep(&token, ":"); + + ret = resctrl_parse_mbm_assignment(r, rdtgrp, event, token); + if (ret) + break; + } + + rdtgroup_kn_unlock(of->kn); + + return ret ?: nbytes; +} + +/** + * resctrl_mon_resource_init() - Initialise global monitoring structures. + * + * Allocate and initialise global monitor resources that do not belong to a + * specific domain. i.e. the rmid_ptrs[] used for the limbo and free lists. + * Called once during boot after the struct rdt_resource's have been configured + * but before the filesystem is mounted. + * Resctrl's cpuhp callbacks may be called before this point to bring a domain + * online. + * + * Returns 0 for success, or -ENOMEM. + */ +int resctrl_mon_resource_init(void) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + int ret; + + if (!r->mon_capable) + return 0; + + ret = dom_data_init(r); + if (ret) + return ret; + + if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_TOTAL_EVENT_ID)) { + mon_event_all[QOS_L3_MBM_TOTAL_EVENT_ID].configurable = true; + resctrl_file_fflags_init("mbm_total_bytes_config", + RFTYPE_MON_INFO | RFTYPE_RES_CACHE); + } + if (resctrl_arch_is_evt_configurable(QOS_L3_MBM_LOCAL_EVENT_ID)) { + mon_event_all[QOS_L3_MBM_LOCAL_EVENT_ID].configurable = true; + resctrl_file_fflags_init("mbm_local_bytes_config", + RFTYPE_MON_INFO | RFTYPE_RES_CACHE); + } + + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_LOCAL_EVENT_ID)) + mba_mbps_default_event = QOS_L3_MBM_LOCAL_EVENT_ID; + else if (resctrl_is_mon_event_enabled(QOS_L3_MBM_TOTAL_EVENT_ID)) + mba_mbps_default_event = QOS_L3_MBM_TOTAL_EVENT_ID; + + if (r->mon.mbm_cntr_assignable) { + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_TOTAL_EVENT_ID)) + mon_event_all[QOS_L3_MBM_TOTAL_EVENT_ID].evt_cfg = r->mon.mbm_cfg_mask; + if (resctrl_is_mon_event_enabled(QOS_L3_MBM_LOCAL_EVENT_ID)) + mon_event_all[QOS_L3_MBM_LOCAL_EVENT_ID].evt_cfg = r->mon.mbm_cfg_mask & + (READS_TO_LOCAL_MEM | + READS_TO_LOCAL_S_MEM | + NON_TEMP_WRITE_TO_LOCAL_MEM); + r->mon.mbm_assign_on_mkdir = true; + resctrl_file_fflags_init("num_mbm_cntrs", + RFTYPE_MON_INFO | RFTYPE_RES_CACHE); + resctrl_file_fflags_init("available_mbm_cntrs", + RFTYPE_MON_INFO | RFTYPE_RES_CACHE); + resctrl_file_fflags_init("event_filter", RFTYPE_ASSIGN_CONFIG); + resctrl_file_fflags_init("mbm_assign_on_mkdir", RFTYPE_MON_INFO | + RFTYPE_RES_CACHE); + resctrl_file_fflags_init("mbm_L3_assignments", RFTYPE_MON_BASE); + } + + return 0; +} + +void resctrl_mon_resource_exit(void) +{ + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); + + dom_data_exit(r); +} |