1 // SPDX-License-Identifier: GPL-2.0-or-later
3 * Copyright (C) 2006 Mike Kravetz IBM Corporation
5 * Hypervisor Call Instrumentation
8 #include <linux/kernel.h>
9 #include <linux/percpu.h>
10 #include <linux/debugfs.h>
11 #include <linux/seq_file.h>
12 #include <linux/cpumask.h>
13 #include <asm/hvcall.h>
14 #include <asm/firmware.h>
15 #include <asm/cputable.h>
16 #include <asm/trace.h>
17 #include <asm/machdep.h>
19 /* For hcall instrumentation. One structure per-hcall, per-CPU */
21 unsigned long num_calls; /* number of calls (on this CPU) */
22 unsigned long tb_total; /* total wall time (mftb) of calls. */
23 unsigned long purr_total; /* total cpu time (PURR) of calls. */
24 unsigned long tb_start;
25 unsigned long purr_start;
27 #define HCALL_STAT_ARRAY_SIZE ((MAX_HCALL_OPCODE >> 2) + 1)
29 DEFINE_PER_CPU(struct hcall_stats[HCALL_STAT_ARRAY_SIZE], hcall_stats);
32 * Routines for displaying the statistics in debugfs
34 static void *hc_start(struct seq_file *m, loff_t *pos)
36 if ((int)*pos < (HCALL_STAT_ARRAY_SIZE-1))
37 return (void *)(unsigned long)(*pos + 1);
42 static void *hc_next(struct seq_file *m, void *p, loff_t * pos)
46 return hc_start(m, pos);
49 static void hc_stop(struct seq_file *m, void *p)
53 static int hc_show(struct seq_file *m, void *p)
55 unsigned long h_num = (unsigned long)p;
56 struct hcall_stats *hs = m->private;
58 if (hs[h_num].num_calls) {
59 if (cpu_has_feature(CPU_FTR_PURR))
60 seq_printf(m, "%lu %lu %lu %lu\n", h_num<<2,
63 hs[h_num].purr_total);
65 seq_printf(m, "%lu %lu %lu\n", h_num<<2,
73 static const struct seq_operations hcall_inst_seq_ops = {
80 static int hcall_inst_seq_open(struct inode *inode, struct file *file)
85 rc = seq_open(file, &hcall_inst_seq_ops);
86 seq = file->private_data;
87 seq->private = file_inode(file)->i_private;
92 static const struct file_operations hcall_inst_seq_fops = {
93 .open = hcall_inst_seq_open,
96 .release = seq_release,
99 #define HCALL_ROOT_DIR "hcall_inst"
100 #define CPU_NAME_BUF_SIZE 32
103 static void probe_hcall_entry(void *ignored, unsigned long opcode, unsigned long *args)
105 struct hcall_stats *h;
107 if (opcode > MAX_HCALL_OPCODE)
110 h = this_cpu_ptr(&hcall_stats[opcode / 4]);
111 h->tb_start = mftb();
112 h->purr_start = mfspr(SPRN_PURR);
115 static void probe_hcall_exit(void *ignored, unsigned long opcode, long retval,
116 unsigned long *retbuf)
118 struct hcall_stats *h;
120 if (opcode > MAX_HCALL_OPCODE)
123 h = this_cpu_ptr(&hcall_stats[opcode / 4]);
125 h->tb_total += mftb() - h->tb_start;
126 h->purr_total += mfspr(SPRN_PURR) - h->purr_start;
129 static int __init hcall_inst_init(void)
131 struct dentry *hcall_root;
132 struct dentry *hcall_file;
133 char cpu_name_buf[CPU_NAME_BUF_SIZE];
136 if (!firmware_has_feature(FW_FEATURE_LPAR))
139 if (register_trace_hcall_entry(probe_hcall_entry, NULL))
142 if (register_trace_hcall_exit(probe_hcall_exit, NULL)) {
143 unregister_trace_hcall_entry(probe_hcall_entry, NULL);
147 hcall_root = debugfs_create_dir(HCALL_ROOT_DIR, NULL);
151 for_each_possible_cpu(cpu) {
152 snprintf(cpu_name_buf, CPU_NAME_BUF_SIZE, "cpu%d", cpu);
153 hcall_file = debugfs_create_file(cpu_name_buf, 0444,
155 per_cpu(hcall_stats, cpu),
156 &hcall_inst_seq_fops);
163 machine_device_initcall(pseries, hcall_inst_init);