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
 25const char *perf_pmu_name(void)
 26{
 27	if (cpum_cf_avail() || cpum_sf_avail())
 28		return "CPU-Measurement Facilities (CPU-MF)";
 29	return "pmu";
 30}
 31EXPORT_SYMBOL(perf_pmu_name);
 32
 33int perf_num_counters(void)
 34{
 35	int num = 0;
 36
 37	if (cpum_cf_avail())
 38		num += PERF_CPUM_CF_MAX_CTR;
 39	if (cpum_sf_avail())
 40		num += PERF_CPUM_SF_MAX_CTR;
 41
 42	return num;
 43}
 44EXPORT_SYMBOL(perf_num_counters);
 45
 46static struct kvm_s390_sie_block *sie_block(struct pt_regs *regs)
 47{
 48	struct stack_frame *stack = (struct stack_frame *) regs->gprs[15];
 49
 50	if (!stack)
 51		return NULL;
 52
 53	return (struct kvm_s390_sie_block *) stack->empty1[0];
 54}
 55
 56static bool is_in_guest(struct pt_regs *regs)
 57{
 58	if (user_mode(regs))
 59		return false;
 60#if IS_ENABLED(CONFIG_KVM)
 61	return instruction_pointer(regs) == (unsigned long) &sie_exit;
 62#else
 63	return false;
 64#endif
 65}
 66
 67static unsigned long guest_is_user_mode(struct pt_regs *regs)
 68{
 69	return sie_block(regs)->gpsw.mask & PSW_MASK_PSTATE;
 70}
 71
 72static unsigned long instruction_pointer_guest(struct pt_regs *regs)
 73{
 74	return sie_block(regs)->gpsw.addr;
 75}
 76
 77unsigned long perf_instruction_pointer(struct pt_regs *regs)
 78{
 79	return is_in_guest(regs) ? instruction_pointer_guest(regs)
 80				 : instruction_pointer(regs);
 81}
 82
 83static unsigned long perf_misc_guest_flags(struct pt_regs *regs)
 84{
 85	return guest_is_user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER
 86					: PERF_RECORD_MISC_GUEST_KERNEL;
 87}
 88
 89static unsigned long perf_misc_flags_sf(struct pt_regs *regs)
 90{
 91	struct perf_sf_sde_regs *sde_regs;
 92	unsigned long flags;
 93
 94	sde_regs = (struct perf_sf_sde_regs *) &regs->int_parm_long;
 95	if (sde_regs->in_guest)
 96		flags = user_mode(regs) ? PERF_RECORD_MISC_GUEST_USER
 97					: PERF_RECORD_MISC_GUEST_KERNEL;
 98	else
 99		flags = user_mode(regs) ? PERF_RECORD_MISC_USER
100					: PERF_RECORD_MISC_KERNEL;
101	return flags;
102}
103
104unsigned long perf_misc_flags(struct pt_regs *regs)
105{
106	/* Check if the cpum_sf PMU has created the pt_regs structure.
107	 * In this case, perf misc flags can be easily extracted.  Otherwise,
108	 * do regular checks on the pt_regs content.
109	 */
110	if (regs->int_code == 0x1407 && regs->int_parm == CPU_MF_INT_SF_PRA)
111		if (!regs->gprs[15])
112			return perf_misc_flags_sf(regs);
113
114	if (is_in_guest(regs))
115		return perf_misc_guest_flags(regs);
116
117	return user_mode(regs) ? PERF_RECORD_MISC_USER
118			       : PERF_RECORD_MISC_KERNEL;
119}
120
121static void print_debug_cf(void)
122{
123	struct cpumf_ctr_info cf_info;
124	int cpu = smp_processor_id();
125
126	memset(&cf_info, 0, sizeof(cf_info));
127	if (!qctri(&cf_info))
128		pr_info("CPU[%i] CPUM_CF: ver=%u.%u A=%04x E=%04x C=%04x\n",
129			cpu, cf_info.cfvn, cf_info.csvn,
130			cf_info.auth_ctl, cf_info.enable_ctl, cf_info.act_ctl);
131}
132
133static void print_debug_sf(void)
134{
135	struct hws_qsi_info_block si;
136	int cpu = smp_processor_id();
137
138	memset(&si, 0, sizeof(si));
139	if (qsi(&si))
140		return;
141
142	pr_info("CPU[%i] CPUM_SF: basic=%i diag=%i min=%lu max=%lu cpu_speed=%u\n",
143		cpu, si.as, si.ad, si.min_sampl_rate, si.max_sampl_rate,
144		si.cpu_speed);
145
146	if (si.as)
147		pr_info("CPU[%i] CPUM_SF: Basic-sampling: a=%i e=%i c=%i"
148			" bsdes=%i tear=%016lx dear=%016lx\n", cpu,
149			si.as, si.es, si.cs, si.bsdes, si.tear, si.dear);
150	if (si.ad)
151		pr_info("CPU[%i] CPUM_SF: Diagnostic-sampling: a=%i e=%i c=%i"
152			" dsdes=%i tear=%016lx dear=%016lx\n", cpu,
153			si.ad, si.ed, si.cd, si.dsdes, si.tear, si.dear);
154}
155
156void perf_event_print_debug(void)
157{
158	unsigned long flags;
159
160	local_irq_save(flags);
161	if (cpum_cf_avail())
162		print_debug_cf();
163	if (cpum_sf_avail())
164		print_debug_sf();
165	local_irq_restore(flags);
166}
167
168/* Service level infrastructure */
169static void sl_print_counter(struct seq_file *m)
170{
171	struct cpumf_ctr_info ci;
172
173	memset(&ci, 0, sizeof(ci));
174	if (qctri(&ci))
175		return;
176
177	seq_printf(m, "CPU-MF: Counter facility: version=%u.%u "
178		   "authorization=%04x\n", ci.cfvn, ci.csvn, ci.auth_ctl);
179}
180
181static void sl_print_sampling(struct seq_file *m)
182{
183	struct hws_qsi_info_block si;
184
185	memset(&si, 0, sizeof(si));
186	if (qsi(&si))
187		return;
188
189	if (!si.as && !si.ad)
190		return;
191
192	seq_printf(m, "CPU-MF: Sampling facility: min_rate=%lu max_rate=%lu"
193		   " cpu_speed=%u\n", si.min_sampl_rate, si.max_sampl_rate,
194		   si.cpu_speed);
195	if (si.as)
196		seq_printf(m, "CPU-MF: Sampling facility: mode=basic"
197			   " sample_size=%u\n", si.bsdes);
198	if (si.ad)
199		seq_printf(m, "CPU-MF: Sampling facility: mode=diagnostic"
200			   " sample_size=%u\n", si.dsdes);
201}
202
203static void service_level_perf_print(struct seq_file *m,
204				     struct service_level *sl)
205{
206	if (cpum_cf_avail())
207		sl_print_counter(m);
208	if (cpum_sf_avail())
209		sl_print_sampling(m);
210}
211
212static struct service_level service_level_perf = {
213	.seq_print = service_level_perf_print,
214};
215
216static int __init service_level_perf_register(void)
217{
218	return register_service_level(&service_level_perf);
219}
220arch_initcall(service_level_perf_register);
221
222static int __perf_callchain_kernel(void *data, unsigned long address, int reliable)
223{
224	struct perf_callchain_entry_ctx *entry = data;
225
226	perf_callchain_store(entry, address);
227	return 0;
228}
229
230void perf_callchain_kernel(struct perf_callchain_entry_ctx *entry,
231			   struct pt_regs *regs)
232{
233	if (user_mode(regs))
234		return;
235	dump_trace(__perf_callchain_kernel, entry, NULL, regs->gprs[15]);
236}
237
238/* Perf definitions for PMU event attributes in sysfs */
239ssize_t cpumf_events_sysfs_show(struct device *dev,
240				struct device_attribute *attr, char *page)
241{
242	struct perf_pmu_events_attr *pmu_attr;
243
244	pmu_attr = container_of(attr, struct perf_pmu_events_attr, attr);
245	return sprintf(page, "event=0x%04llx\n", pmu_attr->id);
246}