The following commit has been merged into the x86/cache branch of tip: Commit-ID: 3c021531131c9ee5df5da739819a515326ee9570 Gitweb: https://git.kernel.org/tip/3c021531131c9ee5df5da739819a515326ee9570 Author: James Morse <james.morse@xxxxxxx> AuthorDate: Tue, 11 Mar 2025 18:36:47 Committer: Borislav Petkov (AMD) <bp@xxxxxxxxx> CommitterDate: Wed, 12 Mar 2025 12:22:22 +01:00 x86/resctrl: Add a helper to avoid reaching into the arch code resource list Resctrl occasionally wants to know something about a specific resource, in these cases it reaches into the arch code's rdt_resources_all[] array. Once the filesystem parts of resctrl are moved to /fs/, this means it will need visibility of the architecture specific struct rdt_hw_resource definition, and the array of all resources. All architectures would also need a r_resctrl member in this struct. Instead, abstract this via a helper to allow architectures to do different things here. Move the level enum to the resctrl header and add a helper to retrieve the struct rdt_resource by 'rid'. resctrl_arch_get_resource() should not return NULL for any value in the enum, it may instead return a dummy resource that is !alloc_enabled && !mon_enabled. Co-developed-by: Dave Martin <Dave.Martin@xxxxxxx> Signed-off-by: Dave Martin <Dave.Martin@xxxxxxx> Signed-off-by: James Morse <james.morse@xxxxxxx> Signed-off-by: Borislav Petkov (AMD) <bp@xxxxxxxxx> Reviewed-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx> Reviewed-by: Reinette Chatre <reinette.chatre@xxxxxxxxx> Reviewed-by: Tony Luck <tony.luck@xxxxxxxxx> Reviewed-by: Fenghua Yu <fenghuay@xxxxxxxxxx> Reviewed-by: Babu Moger <babu.moger@xxxxxxx> Tested-by: Peter Newman <peternewman@xxxxxxxxxx> Tested-by: Carl Worth <carl@xxxxxxxxxxxxxxxxxxxxxx> # arm64 Tested-by: Shaopeng Tan <tan.shaopeng@xxxxxxxxxxxxxx> Tested-by: Amit Singh Tomar <amitsinght@xxxxxxxxxxx> # arm64 Tested-by: Shanker Donthineni <sdonthineni@xxxxxxxxxx> # arm64 Tested-by: Babu Moger <babu.moger@xxxxxxx> Link: https://lore.kernel.org/r/20250311183715.16445-3-james.morse@xxxxxxx --- arch/x86/kernel/cpu/resctrl/core.c | 12 ++++++++++-- arch/x86/kernel/cpu/resctrl/ctrlmondata.c | 2 +- arch/x86/kernel/cpu/resctrl/internal.h | 10 ---------- arch/x86/kernel/cpu/resctrl/monitor.c | 8 ++++---- arch/x86/kernel/cpu/resctrl/rdtgroup.c | 14 +++++++------- include/linux/resctrl.h | 17 +++++++++++++++++ 6 files changed, 39 insertions(+), 24 deletions(-) diff --git a/arch/x86/kernel/cpu/resctrl/core.c b/arch/x86/kernel/cpu/resctrl/core.c index 3d1735e..12b4131 100644 --- a/arch/x86/kernel/cpu/resctrl/core.c +++ b/arch/x86/kernel/cpu/resctrl/core.c @@ -62,7 +62,7 @@ static void mba_wrmsr_amd(struct msr_param *m); #define ctrl_domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].r_resctrl.ctrl_domains) #define mon_domain_init(id) LIST_HEAD_INIT(rdt_resources_all[id].r_resctrl.mon_domains) -struct rdt_hw_resource rdt_resources_all[] = { +struct rdt_hw_resource rdt_resources_all[RDT_NUM_RESOURCES] = { [RDT_RESOURCE_L3] = { .r_resctrl = { @@ -127,6 +127,14 @@ u32 resctrl_arch_system_num_rmid_idx(void) return r->num_rmid; } +struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l) +{ + if (l >= RDT_NUM_RESOURCES) + return NULL; + + return &rdt_resources_all[l].r_resctrl; +} + /* * cache_alloc_hsw_probe() - Have to probe for Intel haswell server CPUs * as they do not have CPUID enumeration support for Cache allocation. @@ -174,7 +182,7 @@ static inline void cache_alloc_hsw_probe(void) bool is_mba_sc(struct rdt_resource *r) { if (!r) - return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.mba_sc; + r = resctrl_arch_get_resource(RDT_RESOURCE_MBA); /* * The software controller support is only applicable to MBA resource. diff --git a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c index 5363511..4af27ef 100644 --- a/arch/x86/kernel/cpu/resctrl/ctrlmondata.c +++ b/arch/x86/kernel/cpu/resctrl/ctrlmondata.c @@ -649,7 +649,7 @@ int rdtgroup_mondata_show(struct seq_file *m, void *arg) resid = md.u.rid; domid = md.u.domid; evtid = md.u.evtid; - r = &rdt_resources_all[resid].r_resctrl; + r = resctrl_arch_get_resource(resid); if (md.u.sum) { /* diff --git a/arch/x86/kernel/cpu/resctrl/internal.h b/arch/x86/kernel/cpu/resctrl/internal.h index 20c898f..75252a7 100644 --- a/arch/x86/kernel/cpu/resctrl/internal.h +++ b/arch/x86/kernel/cpu/resctrl/internal.h @@ -512,16 +512,6 @@ extern struct rdtgroup rdtgroup_default; extern struct dentry *debugfs_resctrl; extern enum resctrl_event_id mba_mbps_default_event; -enum resctrl_res_level { - RDT_RESOURCE_L3, - RDT_RESOURCE_L2, - RDT_RESOURCE_MBA, - RDT_RESOURCE_SMBA, - - /* Must be the last */ - RDT_NUM_RESOURCES, -}; - static inline struct rdt_resource *resctrl_inc(struct rdt_resource *res) { struct rdt_hw_resource *hw_res = resctrl_to_arch_res(res); diff --git a/arch/x86/kernel/cpu/resctrl/monitor.c b/arch/x86/kernel/cpu/resctrl/monitor.c index 94a1d97..58b5b21 100644 --- a/arch/x86/kernel/cpu/resctrl/monitor.c +++ b/arch/x86/kernel/cpu/resctrl/monitor.c @@ -365,7 +365,7 @@ static void limbo_release_entry(struct rmid_entry *entry) */ void __check_limbo(struct rdt_mon_domain *d, bool force_free) { - struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; + 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; @@ -521,7 +521,7 @@ int alloc_rmid(u32 closid) static void add_rmid_to_limbo(struct rmid_entry *entry) { - struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_L3); struct rdt_mon_domain *d; u32 idx; @@ -761,7 +761,7 @@ static void update_mba_bw(struct rdtgroup *rgrp, struct rdt_mon_domain *dom_mbm) struct rdtgroup *entry; u32 cur_bw, user_bw; - r_mba = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl; + r_mba = resctrl_arch_get_resource(RDT_RESOURCE_MBA); evt_id = rgrp->mba_mbps_event; closid = rgrp->closid; @@ -925,7 +925,7 @@ void mbm_handle_overflow(struct work_struct *work) if (!resctrl_mounted || !resctrl_arch_mon_capable()) goto out_unlock; - r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; + 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) { diff --git a/arch/x86/kernel/cpu/resctrl/rdtgroup.c b/arch/x86/kernel/cpu/resctrl/rdtgroup.c index 04b653d..45093b9 100644 --- a/arch/x86/kernel/cpu/resctrl/rdtgroup.c +++ b/arch/x86/kernel/cpu/resctrl/rdtgroup.c @@ -2256,7 +2256,7 @@ static void l2_qos_cfg_update(void *arg) static inline bool is_mba_linear(void) { - return rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl.membw.delay_linear; + return resctrl_arch_get_resource(RDT_RESOURCE_MBA)->membw.delay_linear; } static int set_cache_qos_cfg(int level, bool enable) @@ -2346,8 +2346,8 @@ static void mba_sc_domain_destroy(struct rdt_resource *r, */ static bool supports_mba_mbps(void) { - struct rdt_resource *rmbm = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; - struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl; + struct rdt_resource *rmbm = resctrl_arch_get_resource(RDT_RESOURCE_L3); + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA); return (is_mbm_enabled() && r->alloc_capable && is_mba_linear() && @@ -2360,7 +2360,7 @@ static bool supports_mba_mbps(void) */ static int set_mba_sc(bool mba_sc) { - struct rdt_resource *r = &rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl; + struct rdt_resource *r = resctrl_arch_get_resource(RDT_RESOURCE_MBA); u32 num_closid = resctrl_arch_get_num_closid(r); struct rdt_ctrl_domain *d; unsigned long fflags; @@ -2714,7 +2714,7 @@ static int rdt_get_tree(struct fs_context *fc) resctrl_mounted = true; if (is_mbm_enabled()) { - r = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; + r = resctrl_arch_get_resource(RDT_RESOURCE_L3); list_for_each_entry(dom, &r->mon_domains, hdr.list) mbm_setup_overflow_handler(dom, MBM_OVERFLOW_INTERVAL, RESCTRL_PICK_ANY_CPU); @@ -3951,7 +3951,7 @@ static int rdtgroup_show_options(struct seq_file *seq, struct kernfs_root *kf) if (resctrl_arch_get_cdp_enabled(RDT_RESOURCE_L2)) seq_puts(seq, ",cdpl2"); - if (is_mba_sc(&rdt_resources_all[RDT_RESOURCE_MBA].r_resctrl)) + if (is_mba_sc(resctrl_arch_get_resource(RDT_RESOURCE_MBA))) seq_puts(seq, ",mba_MBps"); if (resctrl_debug) @@ -4151,7 +4151,7 @@ static void clear_childcpus(struct rdtgroup *r, unsigned int cpu) void resctrl_offline_cpu(unsigned int cpu) { - struct rdt_resource *l3 = &rdt_resources_all[RDT_RESOURCE_L3].r_resctrl; + struct rdt_resource *l3 = resctrl_arch_get_resource(RDT_RESOURCE_L3); struct rdt_mon_domain *d; struct rdtgroup *rdtgrp; diff --git a/include/linux/resctrl.h b/include/linux/resctrl.h index d94abba..37279e2 100644 --- a/include/linux/resctrl.h +++ b/include/linux/resctrl.h @@ -37,6 +37,16 @@ enum resctrl_conf_type { CDP_DATA, }; +enum resctrl_res_level { + RDT_RESOURCE_L3, + RDT_RESOURCE_L2, + RDT_RESOURCE_MBA, + RDT_RESOURCE_SMBA, + + /* Must be the last */ + RDT_NUM_RESOURCES, +}; + #define CDP_NUM_TYPES (CDP_DATA + 1) /* @@ -226,6 +236,13 @@ struct rdt_resource { bool cdp_capable; }; +/* + * Get the resource that exists at this level. If the level is not supported + * a dummy/not-capable resource can be returned. Levels >= RDT_NUM_RESOURCES + * will return NULL. + */ +struct rdt_resource *resctrl_arch_get_resource(enum resctrl_res_level l); + /** * struct resctrl_schema - configuration abilities of a resource presented to * user-space
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