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/uaccess.h> |
19 | #include <linux/compat.h> |
20 | #include <linux/sysfs.h> |
21 | #include <asm/stacktrace.h> |
22 | #include <asm/irq.h> |
23 | #include <asm/cpu_mf.h> |
24 | #include <asm/lowcore.h> |
25 | #include <asm/processor.h> |
26 | #include <asm/sysinfo.h> |
27 | #include <asm/unwind.h> |
28 | |
29 | static struct kvm_s390_sie_block *sie_block(struct pt_regs *regs) |
30 | { |
31 | struct stack_frame *stack = (struct stack_frame *) regs->gprs[15]; |
32 | |
33 | if (!stack) |
34 | return NULL; |
35 | |
36 | return (struct kvm_s390_sie_block *)stack->sie_control_block; |
37 | } |
38 | |
39 | static bool is_in_guest(struct pt_regs *regs) |
40 | { |
41 | if (user_mode(regs)) |
42 | return false; |
43 | #if IS_ENABLED(CONFIG_KVM) |
44 | return instruction_pointer(regs) == (unsigned long) &sie_exit; |
45 | #else |
46 | return false; |
47 | #endif |
48 | } |
49 | |
50 | static unsigned long guest_is_user_mode(struct pt_regs *regs) |
51 | { |
52 | return sie_block(regs)->gpsw.mask & PSW_MASK_PSTATE; |
53 | } |
54 | |
55 | static unsigned long instruction_pointer_guest(struct pt_regs *regs) |
56 | { |
57 | return sie_block(regs)->gpsw.addr; |
58 | } |
59 | |
60 | unsigned long perf_instruction_pointer(struct pt_regs *regs) |
61 | { |
62 | return is_in_guest(regs) ? instruction_pointer_guest(regs) |
63 | : instruction_pointer(regs); |
64 | } |
65 | |
66 | static unsigned long perf_misc_guest_flags(struct pt_regs *regs) |
67 | { |
68 | return guest_is_user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER |
69 | : PERF_RECORD_MISC_GUEST_KERNEL; |
70 | } |
71 | |
72 | static unsigned long perf_misc_flags_sf(struct pt_regs *regs) |
73 | { |
74 | struct perf_sf_sde_regs *sde_regs; |
75 | unsigned long flags; |
76 | |
77 | sde_regs = (struct perf_sf_sde_regs *) ®s->int_parm_long; |
78 | if (sde_regs->in_guest) |
79 | flags = user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER |
80 | : PERF_RECORD_MISC_GUEST_KERNEL; |
81 | else |
82 | flags = user_mode(regs) ? PERF_RECORD_MISC_USER |
83 | : PERF_RECORD_MISC_KERNEL; |
84 | return flags; |
85 | } |
86 | |
87 | unsigned long perf_misc_flags(struct pt_regs *regs) |
88 | { |
89 | /* Check if the cpum_sf PMU has created the pt_regs structure. |
90 | * In this case, perf misc flags can be easily extracted. Otherwise, |
91 | * do regular checks on the pt_regs content. |
92 | */ |
93 | if (regs->int_code == 0x1407 && regs->int_parm == CPU_MF_INT_SF_PRA) |
94 | if (!regs->gprs[15]) |
95 | return perf_misc_flags_sf(regs); |
96 | |
97 | if (is_in_guest(regs)) |
98 | return perf_misc_guest_flags(regs); |
99 | |
100 | return user_mode(regs) ? PERF_RECORD_MISC_USER |
101 | : PERF_RECORD_MISC_KERNEL; |
102 | } |
103 | |
104 | static void print_debug_cf(void) |
105 | { |
106 | struct cpumf_ctr_info cf_info; |
107 | int cpu = smp_processor_id(); |
108 | |
109 | memset(&cf_info, 0, sizeof(cf_info)); |
110 | if (!qctri(&cf_info)) |
111 | pr_info("CPU[%i] CPUM_CF: ver=%u.%u A=%04x E=%04x C=%04x\n" , |
112 | cpu, cf_info.cfvn, cf_info.csvn, |
113 | cf_info.auth_ctl, cf_info.enable_ctl, cf_info.act_ctl); |
114 | } |
115 | |
116 | static void print_debug_sf(void) |
117 | { |
118 | struct hws_qsi_info_block si; |
119 | int cpu = smp_processor_id(); |
120 | |
121 | memset(&si, 0, sizeof(si)); |
122 | if (qsi(&si)) |
123 | return; |
124 | |
125 | pr_info("CPU[%i] CPUM_SF: basic=%i diag=%i min=%lu max=%lu cpu_speed=%u\n" , |
126 | cpu, si.as, si.ad, si.min_sampl_rate, si.max_sampl_rate, |
127 | si.cpu_speed); |
128 | |
129 | if (si.as) |
130 | pr_info("CPU[%i] CPUM_SF: Basic-sampling: a=%i e=%i c=%i" |
131 | " bsdes=%i tear=%016lx dear=%016lx\n" , cpu, |
132 | si.as, si.es, si.cs, si.bsdes, si.tear, si.dear); |
133 | if (si.ad) |
134 | pr_info("CPU[%i] CPUM_SF: Diagnostic-sampling: a=%i e=%i c=%i" |
135 | " dsdes=%i tear=%016lx dear=%016lx\n" , cpu, |
136 | si.ad, si.ed, si.cd, si.dsdes, si.tear, si.dear); |
137 | } |
138 | |
139 | void perf_event_print_debug(void) |
140 | { |
141 | unsigned long flags; |
142 | |
143 | local_irq_save(flags); |
144 | if (cpum_cf_avail()) |
145 | print_debug_cf(); |
146 | if (cpum_sf_avail()) |
147 | print_debug_sf(); |
148 | local_irq_restore(flags); |
149 | } |
150 | |
151 | /* Service level infrastructure */ |
152 | static void sl_print_counter(struct seq_file *m) |
153 | { |
154 | struct cpumf_ctr_info ci; |
155 | |
156 | memset(&ci, 0, sizeof(ci)); |
157 | if (qctri(&ci)) |
158 | return; |
159 | |
160 | seq_printf(m, fmt: "CPU-MF: Counter facility: version=%u.%u " |
161 | "authorization=%04x\n" , ci.cfvn, ci.csvn, ci.auth_ctl); |
162 | } |
163 | |
164 | static void sl_print_sampling(struct seq_file *m) |
165 | { |
166 | struct hws_qsi_info_block si; |
167 | |
168 | memset(&si, 0, sizeof(si)); |
169 | if (qsi(&si)) |
170 | return; |
171 | |
172 | if (!si.as && !si.ad) |
173 | return; |
174 | |
175 | seq_printf(m, fmt: "CPU-MF: Sampling facility: min_rate=%lu max_rate=%lu" |
176 | " cpu_speed=%u\n" , si.min_sampl_rate, si.max_sampl_rate, |
177 | si.cpu_speed); |
178 | if (si.as) |
179 | seq_printf(m, fmt: "CPU-MF: Sampling facility: mode=basic" |
180 | " sample_size=%u\n" , si.bsdes); |
181 | if (si.ad) |
182 | seq_printf(m, fmt: "CPU-MF: Sampling facility: mode=diagnostic" |
183 | " sample_size=%u\n" , si.dsdes); |
184 | } |
185 | |
186 | static void service_level_perf_print(struct seq_file *m, |
187 | struct service_level *sl) |
188 | { |
189 | if (cpum_cf_avail()) |
190 | sl_print_counter(m); |
191 | if (cpum_sf_avail()) |
192 | sl_print_sampling(m); |
193 | } |
194 | |
195 | static struct service_level service_level_perf = { |
196 | .seq_print = service_level_perf_print, |
197 | }; |
198 | |
199 | static int __init service_level_perf_register(void) |
200 | { |
201 | return register_service_level(&service_level_perf); |
202 | } |
203 | arch_initcall(service_level_perf_register); |
204 | |
205 | void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry, |
206 | struct pt_regs *regs) |
207 | { |
208 | struct unwind_state state; |
209 | unsigned long addr; |
210 | |
211 | unwind_for_each_frame(&state, current, regs, 0) { |
212 | addr = unwind_get_return_address(state: &state); |
213 | if (!addr || perf_callchain_store(ctx: entry, ip: addr)) |
214 | return; |
215 | } |
216 | } |
217 | |
218 | void perf_callchain_user(struct perf_callchain_entry_ctx *entry, |
219 | struct pt_regs *regs) |
220 | { |
221 | struct stack_frame_user __user *sf; |
222 | unsigned long ip, sp; |
223 | bool first = true; |
224 | |
225 | if (is_compat_task()) |
226 | return; |
227 | perf_callchain_store(ctx: entry, ip: instruction_pointer(regs)); |
228 | sf = (void __user *)user_stack_pointer(regs); |
229 | pagefault_disable(); |
230 | while (entry->nr < entry->max_stack) { |
231 | if (__get_user(sp, &sf->back_chain)) |
232 | break; |
233 | if (__get_user(ip, &sf->gprs[8])) |
234 | break; |
235 | if (ip & 0x1) { |
236 | /* |
237 | * If the instruction address is invalid, and this |
238 | * is the first stack frame, assume r14 has not |
239 | * been written to the stack yet. Otherwise exit. |
240 | */ |
241 | if (first && !(regs->gprs[14] & 0x1)) |
242 | ip = regs->gprs[14]; |
243 | else |
244 | break; |
245 | } |
246 | perf_callchain_store(ctx: entry, ip); |
247 | /* Sanity check: ABI requires SP to be aligned 8 bytes. */ |
248 | if (!sp || sp & 0x7) |
249 | break; |
250 | sf = (void __user *)sp; |
251 | first = false; |
252 | } |
253 | pagefault_enable(); |
254 | } |
255 | |
256 | /* Perf definitions for PMU event attributes in sysfs */ |
257 | ssize_t cpumf_events_sysfs_show(struct device *dev, |
258 | struct device_attribute *attr, char *page) |
259 | { |
260 | struct perf_pmu_events_attr *pmu_attr; |
261 | |
262 | pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr); |
263 | return sprintf(buf: page, fmt: "event=0x%04llx\n" , pmu_attr->id); |
264 | } |
265 | |