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 /* For hcall instrumentation. One structure per-hcall, per-CPU */ 33 struct hcall_stats { 34 unsigned long num_calls; /* number of calls (on this CPU) */ 35 unsigned long tb_total; /* total wall time (mftb) of calls. */ 36 unsigned long purr_total; /* total cpu time (PURR) of calls. */ 37 unsigned long tb_start; 38 unsigned long purr_start; 39 }; 40 #define HCALL_STAT_ARRAY_SIZE ((MAX_HCALL_OPCODE >> 2) + 1) 41 42 DEFINE_PER_CPU(struct hcall_stats[HCALL_STAT_ARRAY_SIZE], hcall_stats); 43 44 /* 45 * Routines for displaying the statistics in debugfs 46 */ 47 static void *hc_start(struct seq_file *m, loff_t *pos) 48 { 49 if ((int)*pos < (HCALL_STAT_ARRAY_SIZE-1)) 50 return (void *)(unsigned long)(*pos + 1); 51 52 return NULL; 53 } 54 55 static void *hc_next(struct seq_file *m, void *p, loff_t * pos) 56 { 57 ++*pos; 58 59 return hc_start(m, pos); 60 } 61 62 static void hc_stop(struct seq_file *m, void *p) 63 { 64 } 65 66 static int hc_show(struct seq_file *m, void *p) 67 { 68 unsigned long h_num = (unsigned long)p; 69 struct hcall_stats *hs = m->private; 70 71 if (hs[h_num].num_calls) { 72 if (cpu_has_feature(CPU_FTR_PURR)) 73 seq_printf(m, "%lu %lu %lu %lu\n", h_num<<2, 74 hs[h_num].num_calls, 75 hs[h_num].tb_total, 76 hs[h_num].purr_total); 77 else 78 seq_printf(m, "%lu %lu %lu\n", h_num<<2, 79 hs[h_num].num_calls, 80 hs[h_num].tb_total); 81 } 82 83 return 0; 84 } 85 86 static const struct seq_operations hcall_inst_seq_ops = { 87 .start = hc_start, 88 .next = hc_next, 89 .stop = hc_stop, 90 .show = hc_show 91 }; 92 93 static int hcall_inst_seq_open(struct inode *inode, struct file *file) 94 { 95 int rc; 96 struct seq_file *seq; 97 98 rc = seq_open(file, &hcall_inst_seq_ops); 99 seq = file->private_data; 100 seq->private = file_inode(file)->i_private; 101 102 return rc; 103 } 104 105 static const struct file_operations hcall_inst_seq_fops = { 106 .open = hcall_inst_seq_open, 107 .read = seq_read, 108 .llseek = seq_lseek, 109 .release = seq_release, 110 }; 111 112 #define HCALL_ROOT_DIR "hcall_inst" 113 #define CPU_NAME_BUF_SIZE 32 114 115 116 static void probe_hcall_entry(void *ignored, unsigned long opcode, unsigned long *args) 117 { 118 struct hcall_stats *h; 119 120 if (opcode > MAX_HCALL_OPCODE) 121 return; 122 123 h = this_cpu_ptr(&hcall_stats[opcode / 4]); 124 h->tb_start = mftb(); 125 h->purr_start = mfspr(SPRN_PURR); 126 } 127 128 static void probe_hcall_exit(void *ignored, unsigned long opcode, long retval, 129 unsigned long *retbuf) 130 { 131 struct hcall_stats *h; 132 133 if (opcode > MAX_HCALL_OPCODE) 134 return; 135 136 h = this_cpu_ptr(&hcall_stats[opcode / 4]); 137 h->num_calls++; 138 h->tb_total += mftb() - h->tb_start; 139 h->purr_total += mfspr(SPRN_PURR) - h->purr_start; 140 } 141 142 static int __init hcall_inst_init(void) 143 { 144 struct dentry *hcall_root; 145 struct dentry *hcall_file; 146 char cpu_name_buf[CPU_NAME_BUF_SIZE]; 147 int cpu; 148 149 if (!firmware_has_feature(FW_FEATURE_LPAR)) 150 return 0; 151 152 if (register_trace_hcall_entry(probe_hcall_entry, NULL)) 153 return -EINVAL; 154 155 if (register_trace_hcall_exit(probe_hcall_exit, NULL)) { 156 unregister_trace_hcall_entry(probe_hcall_entry, NULL); 157 return -EINVAL; 158 } 159 160 hcall_root = debugfs_create_dir(HCALL_ROOT_DIR, NULL); 161 if (!hcall_root) 162 return -ENOMEM; 163 164 for_each_possible_cpu(cpu) { 165 snprintf(cpu_name_buf, CPU_NAME_BUF_SIZE, "cpu%d", cpu); 166 hcall_file = debugfs_create_file(cpu_name_buf, 0444, 167 hcall_root, 168 per_cpu(hcall_stats, cpu), 169 &hcall_inst_seq_fops); 170 if (!hcall_file) 171 return -ENOMEM; 172 } 173 174 return 0; 175 } 176 machine_device_initcall(pseries, hcall_inst_init); 177