arch/powerpc/platforms/pseries/hvCall_inst.c

   1 /*
   2  * Copyright (C) 2006 Mike Kravetz IBM Corporation
   3  *
   4  * Hypervisor Call Instrumentation
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  19  */
  20
  21 #include <linux/kernel.h>
  22 #include <linux/percpu.h>
  23 #include <linux/debugfs.h>
  24 #include <linux/seq_file.h>
  25 #include <linux/cpumask.h>
  26 #include <asm/hvcall.h>
  27 #include <asm/firmware.h>
  28 #include <asm/cputable.h>
  29 #include <asm/trace.h>
  30 #include <asm/machdep.h>
  31
  32 DEFINE_PER_CPU(struct hcall_stats[HCALL_STAT_ARRAY_SIZE], hcall_stats);
  33
  34 /*
  35  * Routines for displaying the statistics in debugfs
  36  */
  37 static void *hc_start(struct seq_file *m, loff_t *pos)
  38 {
  39         if ((int)*pos < (HCALL_STAT_ARRAY_SIZE-1))
  40                 return (void *)(unsigned long)(*pos + 1);
  41
  42         return NULL;
  43 }
  44
  45 static void *hc_next(struct seq_file *m, void *p, loff_t * pos)
  46 {
  47         ++*pos;
  48
  49         return hc_start(m, pos);
  50 }
  51
  52 static void hc_stop(struct seq_file *m, void *p)
  53 {
  54 }
  55
  56 static int hc_show(struct seq_file *m, void *p)
  57 {
  58         unsigned long h_num = (unsigned long)p;
  59         struct hcall_stats *hs = m->private;
  60
  61         if (hs[h_num].num_calls) {
  62                 if (cpu_has_feature(CPU_FTR_PURR))
  63                         seq_printf(m, "%lu %lu %lu %lu\n", h_num<<2,
  64                                    hs[h_num].num_calls,
  65                                    hs[h_num].tb_total,
  66                                    hs[h_num].purr_total);
  67                 else
  68                         seq_printf(m, "%lu %lu %lu\n", h_num<<2,
  69                                    hs[h_num].num_calls,
  70                                    hs[h_num].tb_total);
  71         }
  72
  73         return 0;
  74 }
  75
  76 static const struct seq_operations hcall_inst_seq_ops = {
  77         .start = hc_start,
  78         .next  = hc_next,
  79         .stop  = hc_stop,
  80         .show  = hc_show
  81 };
  82
  83 static int hcall_inst_seq_open(struct inode *inode, struct file *file)
  84 {
  85         int rc;
  86         struct seq_file *seq;
  87
  88         rc = seq_open(file, &hcall_inst_seq_ops);
  89         seq = file->private_data;
  90         seq->private = file_inode(file)->i_private;
  91
  92         return rc;
  93 }
  94
  95 static const struct file_operations hcall_inst_seq_fops = {
  96         .open = hcall_inst_seq_open,
  97         .read = seq_read,
  98         .llseek = seq_lseek,
  99         .release = seq_release,
 100 };
 101
 102 #define HCALL_ROOT_DIR          "hcall_inst"
 103 #define CPU_NAME_BUF_SIZE       32
 104
 105
 106 static void probe_hcall_entry(void *ignored, unsigned long opcode, unsigned long *args)
 107 {
 108         struct hcall_stats *h;
 109
 110         if (opcode > MAX_HCALL_OPCODE)
 111                 return;
 112
 113         h = this_cpu_ptr(&hcall_stats[opcode / 4]);
 114         h->tb_start = mftb();
 115         h->purr_start = mfspr(SPRN_PURR);
 116 }
 117
 118 static void probe_hcall_exit(void *ignored, unsigned long opcode, unsigned long retval,
 119                              unsigned long *retbuf)
 120 {
 121         struct hcall_stats *h;
 122
 123         if (opcode > MAX_HCALL_OPCODE)
 124                 return;
 125
 126         h = this_cpu_ptr(&hcall_stats[opcode / 4]);
 127         h->num_calls++;
 128         h->tb_total += mftb() - h->tb_start;
 129         h->purr_total += mfspr(SPRN_PURR) - h->purr_start;
 130 }
 131
 132 static int __init hcall_inst_init(void)
 133 {
 134         struct dentry *hcall_root;
 135         struct dentry *hcall_file;
 136         char cpu_name_buf[CPU_NAME_BUF_SIZE];
 137         int cpu;
 138
 139         if (!firmware_has_feature(FW_FEATURE_LPAR))
 140                 return 0;
 141
 142         if (register_trace_hcall_entry(probe_hcall_entry, NULL))
 143                 return -EINVAL;
 144
 145         if (register_trace_hcall_exit(probe_hcall_exit, NULL)) {
 146                 unregister_trace_hcall_entry(probe_hcall_entry, NULL);
 147                 return -EINVAL;
 148         }
 149
 150         hcall_root = debugfs_create_dir(HCALL_ROOT_DIR, NULL);
 151         if (!hcall_root)
 152                 return -ENOMEM;
 153
 154         for_each_possible_cpu(cpu) {
 155                 snprintf(cpu_name_buf, CPU_NAME_BUF_SIZE, "cpu%d", cpu);
 156                 hcall_file = debugfs_create_file(cpu_name_buf, S_IRUGO,
 157                                                  hcall_root,
 158                                                  per_cpu(hcall_stats, cpu),
 159                                                  &hcall_inst_seq_fops);
 160                 if (!hcall_file)
 161                         return -ENOMEM;
 162         }
 163
 164         return 0;
 165 }
 166 machine_device_initcall(pseries, hcall_inst_init);