blob: bcc1b67417a84b066d65ac9e37a851acf893e10d [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0-or-later
/*
* Copyright (C) 2006 Mike Kravetz IBM Corporation
*
* Hypervisor Call Instrumentation
*/
#include <linux/kernel.h>
#include <linux/percpu.h>
#include <linux/debugfs.h>
#include <linux/seq_file.h>
#include <linux/cpumask.h>
#include <asm/hvcall.h>
#include <asm/firmware.h>
#include <asm/cputable.h>
#include <asm/trace.h>
#include <asm/machdep.h>
/* For hcall instrumentation. One structure per-hcall, per-CPU */
struct hcall_stats {
unsigned long num_calls; /* number of calls (on this CPU) */
unsigned long tb_total; /* total wall time (mftb) of calls. */
unsigned long purr_total; /* total cpu time (PURR) of calls. */
unsigned long tb_start;
unsigned long purr_start;
};
#define HCALL_STAT_ARRAY_SIZE ((MAX_HCALL_OPCODE >> 2) + 1)
DEFINE_PER_CPU(struct hcall_stats[HCALL_STAT_ARRAY_SIZE], hcall_stats);
/*
* Routines for displaying the statistics in debugfs
*/
static void *hc_start(struct seq_file *m, loff_t *pos)
{
if ((int)*pos < (HCALL_STAT_ARRAY_SIZE-1))
return (void *)(unsigned long)(*pos + 1);
return NULL;
}
static void *hc_next(struct seq_file *m, void *p, loff_t * pos)
{
++*pos;
return hc_start(m, pos);
}
static void hc_stop(struct seq_file *m, void *p)
{
}
static int hc_show(struct seq_file *m, void *p)
{
unsigned long h_num = (unsigned long)p;
struct hcall_stats *hs = m->private;
if (hs[h_num].num_calls) {
if (cpu_has_feature(CPU_FTR_PURR))
seq_printf(m, "%lu %lu %lu %lu\n", h_num<<2,
hs[h_num].num_calls,
hs[h_num].tb_total,
hs[h_num].purr_total);
else
seq_printf(m, "%lu %lu %lu\n", h_num<<2,
hs[h_num].num_calls,
hs[h_num].tb_total);
}
return 0;
}
static const struct seq_operations hcall_inst_seq_ops = {
.start = hc_start,
.next = hc_next,
.stop = hc_stop,
.show = hc_show
};
static int hcall_inst_seq_open(struct inode *inode, struct file *file)
{
int rc;
struct seq_file *seq;
rc = seq_open(file, &hcall_inst_seq_ops);
seq = file->private_data;
seq->private = file_inode(file)->i_private;
return rc;
}
static const struct file_operations hcall_inst_seq_fops = {
.open = hcall_inst_seq_open,
.read = seq_read,
.llseek = seq_lseek,
.release = seq_release,
};
#define HCALL_ROOT_DIR "hcall_inst"
#define CPU_NAME_BUF_SIZE 32
static void probe_hcall_entry(void *ignored, unsigned long opcode, unsigned long *args)
{
struct hcall_stats *h;
if (opcode > MAX_HCALL_OPCODE)
return;
h = this_cpu_ptr(&hcall_stats[opcode / 4]);
h->tb_start = mftb();
h->purr_start = mfspr(SPRN_PURR);
}
static void probe_hcall_exit(void *ignored, unsigned long opcode, long retval,
unsigned long *retbuf)
{
struct hcall_stats *h;
if (opcode > MAX_HCALL_OPCODE)
return;
h = this_cpu_ptr(&hcall_stats[opcode / 4]);
h->num_calls++;
h->tb_total += mftb() - h->tb_start;
h->purr_total += mfspr(SPRN_PURR) - h->purr_start;
}
static int __init hcall_inst_init(void)
{
struct dentry *hcall_root;
struct dentry *hcall_file;
char cpu_name_buf[CPU_NAME_BUF_SIZE];
int cpu;
if (!firmware_has_feature(FW_FEATURE_LPAR))
return 0;
if (register_trace_hcall_entry(probe_hcall_entry, NULL))
return -EINVAL;
if (register_trace_hcall_exit(probe_hcall_exit, NULL)) {
unregister_trace_hcall_entry(probe_hcall_entry, NULL);
return -EINVAL;
}
hcall_root = debugfs_create_dir(HCALL_ROOT_DIR, NULL);
if (!hcall_root)
return -ENOMEM;
for_each_possible_cpu(cpu) {
snprintf(cpu_name_buf, CPU_NAME_BUF_SIZE, "cpu%d", cpu);
hcall_file = debugfs_create_file(cpu_name_buf, 0444,
hcall_root,
per_cpu(hcall_stats, cpu),
&hcall_inst_seq_fops);
if (!hcall_file)
return -ENOMEM;
}
return 0;
}
machine_device_initcall(pseries, hcall_inst_init);