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
  31 DEFINE_PER_CPU(struct hcall_stats[HCALL_STAT_ARRAY_SIZE], hcall_stats);
  32
  33 /*
  34  * Routines for displaying the statistics in debugfs
  35  */
  36 static void *hc_start(struct seq_file *m, loff_t *pos)
  37 {
  38         if ((int)*pos < (HCALL_STAT_ARRAY_SIZE-1))
  39                 return (void *)(unsigned long)(*pos + 1);
  40
  41         return NULL;
  42 }
  43
  44 static void *hc_next(struct seq_file *m, void *p, loff_t * pos)
  45 {
  46         ++*pos;
  47
  48         return hc_start(m, pos);
  49 }
  50
  51 static void hc_stop(struct seq_file *m, void *p)
  52 {
  53 }
  54
  55 static int hc_show(struct seq_file *m, void *p)
  56 {
  57         unsigned long h_num = (unsigned long)p;
  58         struct hcall_stats *hs = m->private;
  59
  60         if (hs[h_num].num_calls) {
  61                 if (cpu_has_feature(CPU_FTR_PURR))
  62                         seq_printf(m, "%lu %lu %lu %lu\n", h_num<<2,
  63                                    hs[h_num].num_calls,
  64                                    hs[h_num].tb_total,
  65                                    hs[h_num].purr_total);
  66                 else
  67                         seq_printf(m, "%lu %lu %lu\n", h_num<<2,
  68                                    hs[h_num].num_calls,
  69                                    hs[h_num].tb_total);
  70         }
  71
  72         return 0;
  73 }
  74
  75 static const struct seq_operations hcall_inst_seq_ops = {
  76         .start = hc_start,
  77         .next  = hc_next,
  78         .stop  = hc_stop,
  79         .show  = hc_show
  80 };
  81
  82 static int hcall_inst_seq_open(struct inode *inode, struct file *file)
  83 {
  84         int rc;
  85         struct seq_file *seq;
  86
  87         rc = seq_open(file, &hcall_inst_seq_ops);
  88         seq = file->private_data;
  89         seq->private = file->f_path.dentry->d_inode->i_private;
  90
  91         return rc;
  92 }
  93
  94 static const struct file_operations hcall_inst_seq_fops = {
  95         .open = hcall_inst_seq_open,
  96         .read = seq_read,
  97         .llseek = seq_lseek,
  98         .release = seq_release,
  99 };
 100
 101 #define HCALL_ROOT_DIR          "hcall_inst"
 102 #define CPU_NAME_BUF_SIZE       32
 103
 104
 105 static void probe_hcall_entry(void *ignored, unsigned long opcode, unsigned long *args)
 106 {
 107         struct hcall_stats *h;
 108
 109         if (opcode > MAX_HCALL_OPCODE)
 110                 return;
 111
 112         h = &__get_cpu_var(hcall_stats)[opcode / 4];
 113         h->tb_start = mftb();
 114         h->purr_start = mfspr(SPRN_PURR);
 115 }
 116
 117 static void probe_hcall_exit(void *ignored, unsigned long opcode, unsigned long retval,
 118                              unsigned long *retbuf)
 119 {
 120         struct hcall_stats *h;
 121
 122         if (opcode > MAX_HCALL_OPCODE)
 123                 return;
 124
 125         h = &__get_cpu_var(hcall_stats)[opcode / 4];
 126         h->num_calls++;
 127         h->tb_total += mftb() - h->tb_start;
 128         h->purr_total += mfspr(SPRN_PURR) - h->purr_start;
 129 }
 130
 131 static int __init hcall_inst_init(void)
 132 {
 133         struct dentry *hcall_root;
 134         struct dentry *hcall_file;
 135         char cpu_name_buf[CPU_NAME_BUF_SIZE];
 136         int cpu;
 137
 138         if (!firmware_has_feature(FW_FEATURE_LPAR))
 139                 return 0;
 140
 141         if (register_trace_hcall_entry(probe_hcall_entry, NULL))
 142                 return -EINVAL;
 143
 144         if (register_trace_hcall_exit(probe_hcall_exit, NULL)) {
 145                 unregister_trace_hcall_entry(probe_hcall_entry, NULL);
 146                 return -EINVAL;
 147         }
 148
 149         hcall_root = debugfs_create_dir(HCALL_ROOT_DIR, NULL);
 150         if (!hcall_root)
 151                 return -ENOMEM;
 152
 153         for_each_possible_cpu(cpu) {
 154                 snprintf(cpu_name_buf, CPU_NAME_BUF_SIZE, "cpu%d", cpu);
 155                 hcall_file = debugfs_create_file(cpu_name_buf, S_IRUGO,
 156                                                  hcall_root,
 157                                                  per_cpu(hcall_stats, cpu),
 158                                                  &hcall_inst_seq_fops);
 159                 if (!hcall_file)
 160                         return -ENOMEM;
 161         }
 162
 163         return 0;
 164 }
 165 __initcall(hcall_inst_init);