1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Performance event support for s390x 4 * 5 * Copyright IBM Corp. 2012, 2013 6 * Author(s): Hendrik Brueckner <brueckner@linux.vnet.ibm.com> 7 */ 8 #define KMSG_COMPONENT "perf" 9 #define pr_fmt(fmt) KMSG_COMPONENT ": " fmt 10 11 #include <linux/kernel.h> 12 #include <linux/perf_event.h> 13 #include <linux/kvm_host.h> 14 #include <linux/percpu.h> 15 #include <linux/export.h> 16 #include <linux/seq_file.h> 17 #include <linux/spinlock.h> 18 #include <linux/sysfs.h> 19 #include <asm/irq.h> 20 #include <asm/cpu_mf.h> 21 #include <asm/lowcore.h> 22 #include <asm/processor.h> 23 #include <asm/sysinfo.h> 24 #include <asm/unwind.h> 25 26 static struct kvm_s390_sie_block *sie_block(struct pt_regs *regs) 27 { 28 struct stack_frame *stack = (struct stack_frame *) regs->gprs[15]; 29 30 if (!stack) 31 return NULL; 32 33 return (struct kvm_s390_sie_block *)stack->sie_control_block; 34 } 35 36 static bool is_in_guest(struct pt_regs *regs) 37 { 38 if (user_mode(regs)) 39 return false; 40 #if IS_ENABLED(CONFIG_KVM) 41 return instruction_pointer(regs) == (unsigned long) &sie_exit; 42 #else 43 return false; 44 #endif 45 } 46 47 static unsigned long guest_is_user_mode(struct pt_regs *regs) 48 { 49 return sie_block(regs)->gpsw.mask & PSW_MASK_PSTATE; 50 } 51 52 static unsigned long instruction_pointer_guest(struct pt_regs *regs) 53 { 54 return sie_block(regs)->gpsw.addr; 55 } 56 57 unsigned long perf_instruction_pointer(struct pt_regs *regs) 58 { 59 return is_in_guest(regs) ? instruction_pointer_guest(regs) 60 : instruction_pointer(regs); 61 } 62 63 static unsigned long perf_misc_guest_flags(struct pt_regs *regs) 64 { 65 return guest_is_user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER 66 : PERF_RECORD_MISC_GUEST_KERNEL; 67 } 68 69 static unsigned long perf_misc_flags_sf(struct pt_regs *regs) 70 { 71 struct perf_sf_sde_regs *sde_regs; 72 unsigned long flags; 73 74 sde_regs = (struct perf_sf_sde_regs *) ®s->int_parm_long; 75 if (sde_regs->in_guest) 76 flags = user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER 77 : PERF_RECORD_MISC_GUEST_KERNEL; 78 else 79 flags = user_mode(regs) ? PERF_RECORD_MISC_USER 80 : PERF_RECORD_MISC_KERNEL; 81 return flags; 82 } 83 84 unsigned long perf_misc_flags(struct pt_regs *regs) 85 { 86 /* Check if the cpum_sf PMU has created the pt_regs structure. 87 * In this case, perf misc flags can be easily extracted. Otherwise, 88 * do regular checks on the pt_regs content. 89 */ 90 if (regs->int_code == 0x1407 && regs->int_parm == CPU_MF_INT_SF_PRA) 91 if (!regs->gprs[15]) 92 return perf_misc_flags_sf(regs); 93 94 if (is_in_guest(regs)) 95 return perf_misc_guest_flags(regs); 96 97 return user_mode(regs) ? PERF_RECORD_MISC_USER 98 : PERF_RECORD_MISC_KERNEL; 99 } 100 101 static void print_debug_cf(void) 102 { 103 struct cpumf_ctr_info cf_info; 104 int cpu = smp_processor_id(); 105 106 memset(&cf_info, 0, sizeof(cf_info)); 107 if (!qctri(&cf_info)) 108 pr_info("CPU[%i] CPUM_CF: ver=%u.%u A=%04x E=%04x C=%04x\n", 109 cpu, cf_info.cfvn, cf_info.csvn, 110 cf_info.auth_ctl, cf_info.enable_ctl, cf_info.act_ctl); 111 } 112 113 static void print_debug_sf(void) 114 { 115 struct hws_qsi_info_block si; 116 int cpu = smp_processor_id(); 117 118 memset(&si, 0, sizeof(si)); 119 if (qsi(&si)) 120 return; 121 122 pr_info("CPU[%i] CPUM_SF: basic=%i diag=%i min=%lu max=%lu cpu_speed=%u\n", 123 cpu, si.as, si.ad, si.min_sampl_rate, si.max_sampl_rate, 124 si.cpu_speed); 125 126 if (si.as) 127 pr_info("CPU[%i] CPUM_SF: Basic-sampling: a=%i e=%i c=%i" 128 " bsdes=%i tear=%016lx dear=%016lx\n", cpu, 129 si.as, si.es, si.cs, si.bsdes, si.tear, si.dear); 130 if (si.ad) 131 pr_info("CPU[%i] CPUM_SF: Diagnostic-sampling: a=%i e=%i c=%i" 132 " dsdes=%i tear=%016lx dear=%016lx\n", cpu, 133 si.ad, si.ed, si.cd, si.dsdes, si.tear, si.dear); 134 } 135 136 void perf_event_print_debug(void) 137 { 138 unsigned long flags; 139 140 local_irq_save(flags); 141 if (cpum_cf_avail()) 142 print_debug_cf(); 143 if (cpum_sf_avail()) 144 print_debug_sf(); 145 local_irq_restore(flags); 146 } 147 148 /* Service level infrastructure */ 149 static void sl_print_counter(struct seq_file *m) 150 { 151 struct cpumf_ctr_info ci; 152 153 memset(&ci, 0, sizeof(ci)); 154 if (qctri(&ci)) 155 return; 156 157 seq_printf(m, "CPU-MF: Counter facility: version=%u.%u " 158 "authorization=%04x\n", ci.cfvn, ci.csvn, ci.auth_ctl); 159 } 160 161 static void sl_print_sampling(struct seq_file *m) 162 { 163 struct hws_qsi_info_block si; 164 165 memset(&si, 0, sizeof(si)); 166 if (qsi(&si)) 167 return; 168 169 if (!si.as && !si.ad) 170 return; 171 172 seq_printf(m, "CPU-MF: Sampling facility: min_rate=%lu max_rate=%lu" 173 " cpu_speed=%u\n", si.min_sampl_rate, si.max_sampl_rate, 174 si.cpu_speed); 175 if (si.as) 176 seq_printf(m, "CPU-MF: Sampling facility: mode=basic" 177 " sample_size=%u\n", si.bsdes); 178 if (si.ad) 179 seq_printf(m, "CPU-MF: Sampling facility: mode=diagnostic" 180 " sample_size=%u\n", si.dsdes); 181 } 182 183 static void service_level_perf_print(struct seq_file *m, 184 struct service_level *sl) 185 { 186 if (cpum_cf_avail()) 187 sl_print_counter(m); 188 if (cpum_sf_avail()) 189 sl_print_sampling(m); 190 } 191 192 static struct service_level service_level_perf = { 193 .seq_print = service_level_perf_print, 194 }; 195 196 static int __init service_level_perf_register(void) 197 { 198 return register_service_level(&service_level_perf); 199 } 200 arch_initcall(service_level_perf_register); 201 202 void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, 203 struct pt_regs *regs) 204 { 205 struct unwind_state state; 206 unsigned long addr; 207 208 unwind_for_each_frame(&state, current, regs, 0) { 209 addr = unwind_get_return_address(&state); 210 if (!addr || perf_callchain_store(entry, addr)) 211 return; 212 } 213 } 214 215 /* Perf definitions for PMU event attributes in sysfs */ 216 ssize_t cpumf_events_sysfs_show(struct device *dev, 217 struct device_attribute *attr, char *page) 218 { 219 struct perf_pmu_events_attr *pmu_attr; 220 221 pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); 222 return sprintf(page, "event=0x%04llx\n", pmu_attr->id); 223 } 224