Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Debug Store support |
| 3 | * |
| 4 | * This provides a low-level interface to the hardware's Debug Store |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 5 | * feature that is used for branch trace store (BTS) and |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 6 | * precise-event based sampling (PEBS). |
| 7 | * |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 8 | * It manages: |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 9 | * - DS and BTS hardware configuration |
Markus Metzger | 6abb11a | 2008-11-25 09:05:27 +0100 | [diff] [blame] | 10 | * - buffer overflow handling (to be done) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 11 | * - buffer access |
| 12 | * |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 13 | * It does not do: |
| 14 | * - security checking (is the caller allowed to trace the task) |
| 15 | * - buffer allocation (memory accounting) |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 16 | * |
| 17 | * |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 18 | * Copyright (C) 2007-2009 Intel Corporation. |
| 19 | * Markus Metzger <markus.t.metzger@intel.com>, 2007-2009 |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 20 | */ |
| 21 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 22 | #include <linux/kernel.h> |
| 23 | #include <linux/string.h> |
| 24 | #include <linux/errno.h> |
| 25 | #include <linux/sched.h> |
| 26 | #include <linux/slab.h> |
| 27 | #include <linux/mm.h> |
Markus Metzger | 15879d0 | 2009-04-03 16:43:38 +0200 | [diff] [blame] | 28 | #include <linux/trace_clock.h> |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 29 | |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 30 | #include <asm/ds.h> |
| 31 | |
Markus Metzger | 8a327f6 | 2009-03-13 10:45:07 +0100 | [diff] [blame] | 32 | #include "ds_selftest.h" |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 33 | |
| 34 | /* |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 35 | * The configuration for a particular DS hardware implementation: |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 36 | */ |
| 37 | struct ds_configuration { |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 38 | /* The name of the configuration: */ |
| 39 | const char *name; |
| 40 | |
| 41 | /* The size of pointer-typed fields in DS, BTS, and PEBS: */ |
| 42 | unsigned char sizeof_ptr_field; |
| 43 | |
| 44 | /* The size of a BTS/PEBS record in bytes: */ |
| 45 | unsigned char sizeof_rec[2]; |
| 46 | |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 47 | /* The number of pebs counter reset values in the DS structure. */ |
| 48 | unsigned char nr_counter_reset; |
| 49 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 50 | /* Control bit-masks indexed by enum ds_feature: */ |
| 51 | unsigned long ctl[dsf_ctl_max]; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 52 | }; |
Markus Metzger | ee81151 | 2009-04-03 16:43:47 +0200 | [diff] [blame] | 53 | static struct ds_configuration ds_cfg __read_mostly; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 54 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 55 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 56 | /* Maximal size of a DS configuration: */ |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 57 | #define MAX_SIZEOF_DS 0x80 |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 58 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 59 | /* Maximal size of a BTS record: */ |
| 60 | #define MAX_SIZEOF_BTS (3 * 8) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 61 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 62 | /* BTS and PEBS buffer alignment: */ |
| 63 | #define DS_ALIGNMENT (1 << 3) |
| 64 | |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 65 | /* Number of buffer pointers in DS: */ |
| 66 | #define NUM_DS_PTR_FIELDS 8 |
| 67 | |
| 68 | /* Size of a pebs reset value in DS: */ |
| 69 | #define PEBS_RESET_FIELD_SIZE 8 |
| 70 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 71 | /* Mask of control bits in the DS MSR register: */ |
| 72 | #define BTS_CONTROL \ |
| 73 | ( ds_cfg.ctl[dsf_bts] | \ |
| 74 | ds_cfg.ctl[dsf_bts_kernel] | \ |
| 75 | ds_cfg.ctl[dsf_bts_user] | \ |
| 76 | ds_cfg.ctl[dsf_bts_overflow] ) |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 77 | |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 78 | /* |
| 79 | * A BTS or PEBS tracer. |
| 80 | * |
| 81 | * This holds the configuration of the tracer and serves as a handle |
| 82 | * to identify tracers. |
| 83 | */ |
| 84 | struct ds_tracer { |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 85 | /* The DS context (partially) owned by this tracer. */ |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 86 | struct ds_context *context; |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 87 | /* The buffer provided on ds_request() and its size in bytes. */ |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 88 | void *buffer; |
| 89 | size_t size; |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 90 | }; |
| 91 | |
| 92 | struct bts_tracer { |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 93 | /* The common DS part: */ |
| 94 | struct ds_tracer ds; |
| 95 | |
| 96 | /* The trace including the DS configuration: */ |
| 97 | struct bts_trace trace; |
| 98 | |
| 99 | /* Buffer overflow notification function: */ |
| 100 | bts_ovfl_callback_t ovfl; |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 101 | |
| 102 | /* Active flags affecting trace collection. */ |
| 103 | unsigned int flags; |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 104 | }; |
| 105 | |
| 106 | struct pebs_tracer { |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 107 | /* The common DS part: */ |
| 108 | struct ds_tracer ds; |
| 109 | |
| 110 | /* The trace including the DS configuration: */ |
| 111 | struct pebs_trace trace; |
| 112 | |
| 113 | /* Buffer overflow notification function: */ |
| 114 | pebs_ovfl_callback_t ovfl; |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 115 | }; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 116 | |
| 117 | /* |
| 118 | * Debug Store (DS) save area configuration (see Intel64 and IA32 |
| 119 | * Architectures Software Developer's Manual, section 18.5) |
| 120 | * |
| 121 | * The DS configuration consists of the following fields; different |
| 122 | * architetures vary in the size of those fields. |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 123 | * |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 124 | * - double-word aligned base linear address of the BTS buffer |
| 125 | * - write pointer into the BTS buffer |
| 126 | * - end linear address of the BTS buffer (one byte beyond the end of |
| 127 | * the buffer) |
| 128 | * - interrupt pointer into BTS buffer |
| 129 | * (interrupt occurs when write pointer passes interrupt pointer) |
| 130 | * - double-word aligned base linear address of the PEBS buffer |
| 131 | * - write pointer into the PEBS buffer |
| 132 | * - end linear address of the PEBS buffer (one byte beyond the end of |
| 133 | * the buffer) |
| 134 | * - interrupt pointer into PEBS buffer |
| 135 | * (interrupt occurs when write pointer passes interrupt pointer) |
| 136 | * - value to which counter is reset following counter overflow |
| 137 | * |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 138 | * Later architectures use 64bit pointers throughout, whereas earlier |
| 139 | * architectures use 32bit pointers in 32bit mode. |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 140 | * |
| 141 | * |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 142 | * We compute the base address for the first 8 fields based on: |
| 143 | * - the field size stored in the DS configuration |
| 144 | * - the relative field position |
| 145 | * - an offset giving the start of the respective region |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 146 | * |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 147 | * This offset is further used to index various arrays holding |
| 148 | * information for BTS and PEBS at the respective index. |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 149 | * |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 150 | * On later 32bit processors, we only access the lower 32bit of the |
| 151 | * 64bit pointer fields. The upper halves will be zeroed out. |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 152 | */ |
| 153 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 154 | enum ds_field { |
| 155 | ds_buffer_base = 0, |
| 156 | ds_index, |
| 157 | ds_absolute_maximum, |
| 158 | ds_interrupt_threshold, |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 159 | }; |
| 160 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 161 | enum ds_qualifier { |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 162 | ds_bts = 0, |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 163 | ds_pebs |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 164 | }; |
| 165 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 166 | static inline unsigned long |
| 167 | ds_get(const unsigned char *base, enum ds_qualifier qual, enum ds_field field) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 168 | { |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 169 | base += (ds_cfg.sizeof_ptr_field * (field + (4 * qual))); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 170 | return *(unsigned long *)base; |
| 171 | } |
| 172 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 173 | static inline void |
| 174 | ds_set(unsigned char *base, enum ds_qualifier qual, enum ds_field field, |
| 175 | unsigned long value) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 176 | { |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 177 | base += (ds_cfg.sizeof_ptr_field * (field + (4 * qual))); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 178 | (*(unsigned long *)base) = value; |
| 179 | } |
| 180 | |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 181 | |
| 182 | /* |
Markus Metzger | 6abb11a | 2008-11-25 09:05:27 +0100 | [diff] [blame] | 183 | * Locking is done only for allocating BTS or PEBS resources. |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 184 | */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 185 | static DEFINE_SPINLOCK(ds_lock); |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 186 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 187 | /* |
| 188 | * We either support (system-wide) per-cpu or per-thread allocation. |
| 189 | * We distinguish the two based on the task_struct pointer, where a |
| 190 | * NULL pointer indicates per-cpu allocation for the current cpu. |
| 191 | * |
| 192 | * Allocations are use-counted. As soon as resources are allocated, |
| 193 | * further allocations must be of the same type (per-cpu or |
| 194 | * per-thread). We model this by counting allocations (i.e. the number |
| 195 | * of tracers of a certain type) for one type negatively: |
| 196 | * =0 no tracers |
| 197 | * >0 number of per-thread tracers |
| 198 | * <0 number of per-cpu tracers |
| 199 | * |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 200 | * Tracers essentially gives the number of ds contexts for a certain |
| 201 | * type of allocation. |
| 202 | */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 203 | static atomic_t tracers = ATOMIC_INIT(0); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 204 | |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 205 | static inline int get_tracer(struct task_struct *task) |
Markus Metzger | a95d67f | 2008-01-30 13:31:20 +0100 | [diff] [blame] | 206 | { |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 207 | int error; |
| 208 | |
| 209 | spin_lock_irq(&ds_lock); |
| 210 | |
| 211 | if (task) { |
| 212 | error = -EPERM; |
| 213 | if (atomic_read(&tracers) < 0) |
| 214 | goto out; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 215 | atomic_inc(&tracers); |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 216 | } else { |
| 217 | error = -EPERM; |
| 218 | if (atomic_read(&tracers) > 0) |
| 219 | goto out; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 220 | atomic_dec(&tracers); |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 221 | } |
| 222 | |
| 223 | error = 0; |
| 224 | out: |
| 225 | spin_unlock_irq(&ds_lock); |
| 226 | return error; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 227 | } |
| 228 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 229 | static inline void put_tracer(struct task_struct *task) |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 230 | { |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 231 | if (task) |
| 232 | atomic_dec(&tracers); |
| 233 | else |
| 234 | atomic_inc(&tracers); |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 235 | } |
| 236 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 237 | /* |
| 238 | * The DS context is either attached to a thread or to a cpu: |
| 239 | * - in the former case, the thread_struct contains a pointer to the |
| 240 | * attached context. |
| 241 | * - in the latter case, we use a static array of per-cpu context |
| 242 | * pointers. |
| 243 | * |
| 244 | * Contexts are use-counted. They are allocated on first access and |
| 245 | * deallocated when the last user puts the context. |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 246 | */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 247 | struct ds_context { |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 248 | /* The DS configuration; goes into MSR_IA32_DS_AREA: */ |
| 249 | unsigned char ds[MAX_SIZEOF_DS]; |
| 250 | |
| 251 | /* The owner of the BTS and PEBS configuration, respectively: */ |
| 252 | struct bts_tracer *bts_master; |
| 253 | struct pebs_tracer *pebs_master; |
| 254 | |
| 255 | /* Use count: */ |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 256 | unsigned long count; |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 257 | |
| 258 | /* Pointer to the context pointer field: */ |
| 259 | struct ds_context **this; |
| 260 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 261 | /* The traced task; NULL for cpu tracing: */ |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 262 | struct task_struct *task; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 263 | |
| 264 | /* The traced cpu; only valid if task is NULL: */ |
| 265 | int cpu; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 266 | }; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 267 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 268 | static DEFINE_PER_CPU(struct ds_context *, cpu_context); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 269 | |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 270 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 271 | static struct ds_context *ds_get_context(struct task_struct *task, int cpu) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 272 | { |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 273 | struct ds_context **p_context = |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 274 | (task ? &task->thread.ds_ctx : &per_cpu(cpu_context, cpu)); |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 275 | struct ds_context *context = NULL; |
| 276 | struct ds_context *new_context = NULL; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 277 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 278 | /* Chances are small that we already have a context. */ |
| 279 | new_context = kzalloc(sizeof(*new_context), GFP_KERNEL); |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 280 | if (!new_context) |
| 281 | return NULL; |
| 282 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 283 | spin_lock_irq(&ds_lock); |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 284 | |
| 285 | context = *p_context; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 286 | if (likely(!context)) { |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 287 | context = new_context; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 288 | |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 289 | context->this = p_context; |
| 290 | context->task = task; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 291 | context->cpu = cpu; |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 292 | context->count = 0; |
Markus Metzger | de90add | 2008-11-25 08:52:56 +0100 | [diff] [blame] | 293 | |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 294 | *p_context = context; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 295 | } |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 296 | |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 297 | context->count++; |
| 298 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 299 | spin_unlock_irq(&ds_lock); |
Markus Metzger | cc1dc6d | 2008-12-16 15:51:03 +0100 | [diff] [blame] | 300 | |
| 301 | if (context != new_context) |
| 302 | kfree(new_context); |
| 303 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 304 | return context; |
| 305 | } |
| 306 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 307 | static void ds_put_context(struct ds_context *context) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 308 | { |
Markus Metzger | 8d99b3a | 2009-04-03 16:43:36 +0200 | [diff] [blame] | 309 | struct task_struct *task; |
Markus Metzger | de90add | 2008-11-25 08:52:56 +0100 | [diff] [blame] | 310 | unsigned long irq; |
| 311 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 312 | if (!context) |
| 313 | return; |
| 314 | |
Markus Metzger | de90add | 2008-11-25 08:52:56 +0100 | [diff] [blame] | 315 | spin_lock_irqsave(&ds_lock, irq); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 316 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 317 | if (--context->count) { |
| 318 | spin_unlock_irqrestore(&ds_lock, irq); |
| 319 | return; |
| 320 | } |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 321 | |
Cyrill Gorcunov | 573da42 | 2008-04-28 23:15:04 +0400 | [diff] [blame] | 322 | *(context->this) = NULL; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 323 | |
Markus Metzger | 8d99b3a | 2009-04-03 16:43:36 +0200 | [diff] [blame] | 324 | task = context->task; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 325 | |
Markus Metzger | 8d99b3a | 2009-04-03 16:43:36 +0200 | [diff] [blame] | 326 | if (task) |
| 327 | clear_tsk_thread_flag(task, TIF_DS_AREA_MSR); |
| 328 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 329 | /* |
| 330 | * We leave the (now dangling) pointer to the DS configuration in |
| 331 | * the DS_AREA msr. This is as good or as bad as replacing it with |
| 332 | * NULL - the hardware would crash if we enabled tracing. |
| 333 | * |
| 334 | * This saves us some problems with having to write an msr on a |
| 335 | * different cpu while preventing others from doing the same for the |
| 336 | * next context for that same cpu. |
| 337 | */ |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 338 | |
Markus Metzger | de90add | 2008-11-25 08:52:56 +0100 | [diff] [blame] | 339 | spin_unlock_irqrestore(&ds_lock, irq); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 340 | |
Markus Metzger | 8d99b3a | 2009-04-03 16:43:36 +0200 | [diff] [blame] | 341 | /* The context might still be in use for context switching. */ |
| 342 | if (task && (task != current)) |
| 343 | wait_task_context_switch(task); |
| 344 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 345 | kfree(context); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 346 | } |
| 347 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 348 | static void ds_install_ds_area(struct ds_context *context) |
| 349 | { |
| 350 | unsigned long ds; |
| 351 | |
| 352 | ds = (unsigned long)context->ds; |
| 353 | |
| 354 | /* |
| 355 | * There is a race between the bts master and the pebs master. |
| 356 | * |
| 357 | * The thread/cpu access is synchronized via get/put_cpu() for |
| 358 | * task tracing and via wrmsr_on_cpu for cpu tracing. |
| 359 | * |
| 360 | * If bts and pebs are collected for the same task or same cpu, |
| 361 | * the same confiuration is written twice. |
| 362 | */ |
| 363 | if (context->task) { |
| 364 | get_cpu(); |
| 365 | if (context->task == current) |
| 366 | wrmsrl(MSR_IA32_DS_AREA, ds); |
| 367 | set_tsk_thread_flag(context->task, TIF_DS_AREA_MSR); |
| 368 | put_cpu(); |
| 369 | } else |
| 370 | wrmsr_on_cpu(context->cpu, MSR_IA32_DS_AREA, |
| 371 | (u32)((u64)ds), (u32)((u64)ds >> 32)); |
| 372 | } |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 373 | |
| 374 | /* |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 375 | * Call the tracer's callback on a buffer overflow. |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 376 | * |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 377 | * context: the ds context |
| 378 | * qual: the buffer type |
| 379 | */ |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 380 | static void ds_overflow(struct ds_context *context, enum ds_qualifier qual) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 381 | { |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 382 | switch (qual) { |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 383 | case ds_bts: |
| 384 | if (context->bts_master && |
| 385 | context->bts_master->ovfl) |
| 386 | context->bts_master->ovfl(context->bts_master); |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 387 | break; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 388 | case ds_pebs: |
| 389 | if (context->pebs_master && |
| 390 | context->pebs_master->ovfl) |
| 391 | context->pebs_master->ovfl(context->pebs_master); |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 392 | break; |
| 393 | } |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 394 | } |
| 395 | |
| 396 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 397 | /* |
| 398 | * Write raw data into the BTS or PEBS buffer. |
| 399 | * |
| 400 | * The remainder of any partially written record is zeroed out. |
| 401 | * |
| 402 | * context: the DS context |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 403 | * qual: the buffer type |
| 404 | * record: the data to write |
| 405 | * size: the size of the data |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 406 | */ |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 407 | static int ds_write(struct ds_context *context, enum ds_qualifier qual, |
| 408 | const void *record, size_t size) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 409 | { |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 410 | int bytes_written = 0; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 411 | |
| 412 | if (!record) |
| 413 | return -EINVAL; |
| 414 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 415 | while (size) { |
| 416 | unsigned long base, index, end, write_end, int_th; |
| 417 | unsigned long write_size, adj_write_size; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 418 | |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 419 | /* |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 420 | * Write as much as possible without producing an |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 421 | * overflow interrupt. |
| 422 | * |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 423 | * Interrupt_threshold must either be |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 424 | * - bigger than absolute_maximum or |
| 425 | * - point to a record between buffer_base and absolute_maximum |
| 426 | * |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 427 | * Index points to a valid record. |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 428 | */ |
| 429 | base = ds_get(context->ds, qual, ds_buffer_base); |
| 430 | index = ds_get(context->ds, qual, ds_index); |
| 431 | end = ds_get(context->ds, qual, ds_absolute_maximum); |
| 432 | int_th = ds_get(context->ds, qual, ds_interrupt_threshold); |
| 433 | |
| 434 | write_end = min(end, int_th); |
| 435 | |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 436 | /* |
| 437 | * If we are already beyond the interrupt threshold, |
| 438 | * we fill the entire buffer. |
| 439 | */ |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 440 | if (write_end <= index) |
| 441 | write_end = end; |
| 442 | |
| 443 | if (write_end <= index) |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 444 | break; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 445 | |
| 446 | write_size = min((unsigned long) size, write_end - index); |
| 447 | memcpy((void *)index, record, write_size); |
| 448 | |
| 449 | record = (const char *)record + write_size; |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 450 | size -= write_size; |
| 451 | bytes_written += write_size; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 452 | |
| 453 | adj_write_size = write_size / ds_cfg.sizeof_rec[qual]; |
| 454 | adj_write_size *= ds_cfg.sizeof_rec[qual]; |
| 455 | |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 456 | /* Zero out trailing bytes. */ |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 457 | memset((char *)index + write_size, 0, |
| 458 | adj_write_size - write_size); |
| 459 | index += adj_write_size; |
| 460 | |
| 461 | if (index >= end) |
| 462 | index = base; |
| 463 | ds_set(context->ds, qual, ds_index, index); |
| 464 | |
| 465 | if (index >= int_th) |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 466 | ds_overflow(context, qual); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 467 | } |
| 468 | |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 469 | return bytes_written; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 470 | } |
| 471 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 472 | |
| 473 | /* |
| 474 | * Branch Trace Store (BTS) uses the following format. Different |
| 475 | * architectures vary in the size of those fields. |
| 476 | * - source linear address |
| 477 | * - destination linear address |
| 478 | * - flags |
| 479 | * |
| 480 | * Later architectures use 64bit pointers throughout, whereas earlier |
| 481 | * architectures use 32bit pointers in 32bit mode. |
| 482 | * |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 483 | * We compute the base address for the fields based on: |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 484 | * - the field size stored in the DS configuration |
| 485 | * - the relative field position |
| 486 | * |
| 487 | * In order to store additional information in the BTS buffer, we use |
| 488 | * a special source address to indicate that the record requires |
| 489 | * special interpretation. |
| 490 | * |
| 491 | * Netburst indicated via a bit in the flags field whether the branch |
| 492 | * was predicted; this is ignored. |
| 493 | * |
| 494 | * We use two levels of abstraction: |
| 495 | * - the raw data level defined here |
| 496 | * - an arch-independent level defined in ds.h |
| 497 | */ |
| 498 | |
| 499 | enum bts_field { |
| 500 | bts_from, |
| 501 | bts_to, |
| 502 | bts_flags, |
| 503 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 504 | bts_qual = bts_from, |
Markus Metzger | 15879d0 | 2009-04-03 16:43:38 +0200 | [diff] [blame] | 505 | bts_clock = bts_to, |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 506 | bts_pid = bts_flags, |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 507 | |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 508 | bts_qual_mask = (bts_qual_max - 1), |
| 509 | bts_escape = ((unsigned long)-1 & ~bts_qual_mask) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 510 | }; |
| 511 | |
| 512 | static inline unsigned long bts_get(const char *base, enum bts_field field) |
| 513 | { |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 514 | base += (ds_cfg.sizeof_ptr_field * field); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 515 | return *(unsigned long *)base; |
| 516 | } |
| 517 | |
| 518 | static inline void bts_set(char *base, enum bts_field field, unsigned long val) |
| 519 | { |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 520 | base += (ds_cfg.sizeof_ptr_field * field);; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 521 | (*(unsigned long *)base) = val; |
| 522 | } |
| 523 | |
| 524 | |
| 525 | /* |
| 526 | * The raw BTS data is architecture dependent. |
| 527 | * |
| 528 | * For higher-level users, we give an arch-independent view. |
| 529 | * - ds.h defines struct bts_struct |
| 530 | * - bts_read translates one raw bts record into a bts_struct |
| 531 | * - bts_write translates one bts_struct into the raw format and |
| 532 | * writes it into the top of the parameter tracer's buffer. |
| 533 | * |
| 534 | * return: bytes read/written on success; -Eerrno, otherwise |
| 535 | */ |
Ingo Molnar | e9a22d1 | 2009-03-13 11:54:40 +0100 | [diff] [blame] | 536 | static int |
| 537 | bts_read(struct bts_tracer *tracer, const void *at, struct bts_struct *out) |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 538 | { |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 539 | if (!tracer) |
| 540 | return -EINVAL; |
| 541 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 542 | if (at < tracer->trace.ds.begin) |
| 543 | return -EINVAL; |
| 544 | |
| 545 | if (tracer->trace.ds.end < (at + tracer->trace.ds.size)) |
| 546 | return -EINVAL; |
| 547 | |
| 548 | memset(out, 0, sizeof(*out)); |
| 549 | if ((bts_get(at, bts_qual) & ~bts_qual_mask) == bts_escape) { |
| 550 | out->qualifier = (bts_get(at, bts_qual) & bts_qual_mask); |
Markus Metzger | 15879d0 | 2009-04-03 16:43:38 +0200 | [diff] [blame] | 551 | out->variant.event.clock = bts_get(at, bts_clock); |
| 552 | out->variant.event.pid = bts_get(at, bts_pid); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 553 | } else { |
| 554 | out->qualifier = bts_branch; |
| 555 | out->variant.lbr.from = bts_get(at, bts_from); |
| 556 | out->variant.lbr.to = bts_get(at, bts_to); |
Markus Metzger | d072c25 | 2008-12-16 15:53:11 +0100 | [diff] [blame] | 557 | |
| 558 | if (!out->variant.lbr.from && !out->variant.lbr.to) |
| 559 | out->qualifier = bts_invalid; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 560 | } |
| 561 | |
| 562 | return ds_cfg.sizeof_rec[ds_bts]; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 563 | } |
| 564 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 565 | static int bts_write(struct bts_tracer *tracer, const struct bts_struct *in) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 566 | { |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 567 | unsigned char raw[MAX_SIZEOF_BTS]; |
| 568 | |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 569 | if (!tracer) |
| 570 | return -EINVAL; |
| 571 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 572 | if (MAX_SIZEOF_BTS < ds_cfg.sizeof_rec[ds_bts]) |
| 573 | return -EOVERFLOW; |
| 574 | |
| 575 | switch (in->qualifier) { |
| 576 | case bts_invalid: |
| 577 | bts_set(raw, bts_from, 0); |
| 578 | bts_set(raw, bts_to, 0); |
| 579 | bts_set(raw, bts_flags, 0); |
| 580 | break; |
| 581 | case bts_branch: |
| 582 | bts_set(raw, bts_from, in->variant.lbr.from); |
| 583 | bts_set(raw, bts_to, in->variant.lbr.to); |
| 584 | bts_set(raw, bts_flags, 0); |
| 585 | break; |
| 586 | case bts_task_arrives: |
| 587 | case bts_task_departs: |
| 588 | bts_set(raw, bts_qual, (bts_escape | in->qualifier)); |
Markus Metzger | 15879d0 | 2009-04-03 16:43:38 +0200 | [diff] [blame] | 589 | bts_set(raw, bts_clock, in->variant.event.clock); |
| 590 | bts_set(raw, bts_pid, in->variant.event.pid); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 591 | break; |
| 592 | default: |
| 593 | return -EINVAL; |
| 594 | } |
| 595 | |
| 596 | return ds_write(tracer->ds.context, ds_bts, raw, |
| 597 | ds_cfg.sizeof_rec[ds_bts]); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 598 | } |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 599 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 600 | |
| 601 | static void ds_write_config(struct ds_context *context, |
| 602 | struct ds_trace *cfg, enum ds_qualifier qual) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 603 | { |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 604 | unsigned char *ds = context->ds; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 605 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 606 | ds_set(ds, qual, ds_buffer_base, (unsigned long)cfg->begin); |
| 607 | ds_set(ds, qual, ds_index, (unsigned long)cfg->top); |
| 608 | ds_set(ds, qual, ds_absolute_maximum, (unsigned long)cfg->end); |
| 609 | ds_set(ds, qual, ds_interrupt_threshold, (unsigned long)cfg->ith); |
| 610 | } |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 611 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 612 | static void ds_read_config(struct ds_context *context, |
| 613 | struct ds_trace *cfg, enum ds_qualifier qual) |
| 614 | { |
| 615 | unsigned char *ds = context->ds; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 616 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 617 | cfg->begin = (void *)ds_get(ds, qual, ds_buffer_base); |
| 618 | cfg->top = (void *)ds_get(ds, qual, ds_index); |
| 619 | cfg->end = (void *)ds_get(ds, qual, ds_absolute_maximum); |
| 620 | cfg->ith = (void *)ds_get(ds, qual, ds_interrupt_threshold); |
| 621 | } |
| 622 | |
| 623 | static void ds_init_ds_trace(struct ds_trace *trace, enum ds_qualifier qual, |
| 624 | void *base, size_t size, size_t ith, |
| 625 | unsigned int flags) { |
| 626 | unsigned long buffer, adj; |
| 627 | |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 628 | /* |
| 629 | * Adjust the buffer address and size to meet alignment |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 630 | * constraints: |
| 631 | * - buffer is double-word aligned |
| 632 | * - size is multiple of record size |
| 633 | * |
| 634 | * We checked the size at the very beginning; we have enough |
| 635 | * space to do the adjustment. |
| 636 | */ |
| 637 | buffer = (unsigned long)base; |
| 638 | |
| 639 | adj = ALIGN(buffer, DS_ALIGNMENT) - buffer; |
| 640 | buffer += adj; |
| 641 | size -= adj; |
| 642 | |
| 643 | trace->n = size / ds_cfg.sizeof_rec[qual]; |
| 644 | trace->size = ds_cfg.sizeof_rec[qual]; |
| 645 | |
| 646 | size = (trace->n * trace->size); |
| 647 | |
| 648 | trace->begin = (void *)buffer; |
| 649 | trace->top = trace->begin; |
| 650 | trace->end = (void *)(buffer + size); |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 651 | /* |
| 652 | * The value for 'no threshold' is -1, which will set the |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 653 | * threshold outside of the buffer, just like we want it. |
| 654 | */ |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 655 | ith *= ds_cfg.sizeof_rec[qual]; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 656 | trace->ith = (void *)(buffer + size - ith); |
| 657 | |
| 658 | trace->flags = flags; |
| 659 | } |
| 660 | |
| 661 | |
| 662 | static int ds_request(struct ds_tracer *tracer, struct ds_trace *trace, |
| 663 | enum ds_qualifier qual, struct task_struct *task, |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 664 | int cpu, void *base, size_t size, size_t th) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 665 | { |
| 666 | struct ds_context *context; |
| 667 | int error; |
Markus Metzger | 150f516 | 2009-04-03 16:43:51 +0200 | [diff] [blame] | 668 | size_t req_size; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 669 | |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 670 | error = -EOPNOTSUPP; |
| 671 | if (!ds_cfg.sizeof_rec[qual]) |
| 672 | goto out; |
| 673 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 674 | error = -EINVAL; |
| 675 | if (!base) |
| 676 | goto out; |
| 677 | |
Markus Metzger | 150f516 | 2009-04-03 16:43:51 +0200 | [diff] [blame] | 678 | req_size = ds_cfg.sizeof_rec[qual]; |
| 679 | /* We might need space for alignment adjustments. */ |
| 680 | if (!IS_ALIGNED((unsigned long)base, DS_ALIGNMENT)) |
| 681 | req_size += DS_ALIGNMENT; |
| 682 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 683 | error = -EINVAL; |
Markus Metzger | 150f516 | 2009-04-03 16:43:51 +0200 | [diff] [blame] | 684 | if (size < req_size) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 685 | goto out; |
| 686 | |
| 687 | if (th != (size_t)-1) { |
| 688 | th *= ds_cfg.sizeof_rec[qual]; |
| 689 | |
| 690 | error = -EINVAL; |
| 691 | if (size <= th) |
| 692 | goto out; |
| 693 | } |
| 694 | |
| 695 | tracer->buffer = base; |
| 696 | tracer->size = size; |
| 697 | |
| 698 | error = -ENOMEM; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 699 | context = ds_get_context(task, cpu); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 700 | if (!context) |
| 701 | goto out; |
| 702 | tracer->context = context; |
| 703 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 704 | /* |
| 705 | * Defer any tracer-specific initialization work for the context until |
| 706 | * context ownership has been clarified. |
| 707 | */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 708 | |
| 709 | error = 0; |
| 710 | out: |
| 711 | return error; |
| 712 | } |
| 713 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 714 | static struct bts_tracer *ds_request_bts(struct task_struct *task, int cpu, |
| 715 | void *base, size_t size, |
| 716 | bts_ovfl_callback_t ovfl, size_t th, |
| 717 | unsigned int flags) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 718 | { |
| 719 | struct bts_tracer *tracer; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 720 | int error; |
| 721 | |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 722 | /* Buffer overflow notification is not yet implemented. */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 723 | error = -EOPNOTSUPP; |
| 724 | if (ovfl) |
| 725 | goto out; |
| 726 | |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 727 | error = get_tracer(task); |
| 728 | if (error < 0) |
| 729 | goto out; |
| 730 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 731 | error = -ENOMEM; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 732 | tracer = kzalloc(sizeof(*tracer), GFP_KERNEL); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 733 | if (!tracer) |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 734 | goto out_put_tracer; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 735 | tracer->ovfl = ovfl; |
| 736 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 737 | /* Do some more error checking and acquire a tracing context. */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 738 | error = ds_request(&tracer->ds, &tracer->trace.ds, |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 739 | ds_bts, task, cpu, base, size, th); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 740 | if (error < 0) |
| 741 | goto out_tracer; |
| 742 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 743 | /* Claim the bts part of the tracing context we acquired above. */ |
| 744 | spin_lock_irq(&ds_lock); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 745 | |
| 746 | error = -EPERM; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 747 | if (tracer->ds.context->bts_master) |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 748 | goto out_unlock; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 749 | tracer->ds.context->bts_master = tracer; |
| 750 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 751 | spin_unlock_irq(&ds_lock); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 752 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 753 | /* |
| 754 | * Now that we own the bts part of the context, let's complete the |
| 755 | * initialization for that part. |
| 756 | */ |
| 757 | ds_init_ds_trace(&tracer->trace.ds, ds_bts, base, size, th, flags); |
| 758 | ds_write_config(tracer->ds.context, &tracer->trace.ds, ds_bts); |
| 759 | ds_install_ds_area(tracer->ds.context); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 760 | |
| 761 | tracer->trace.read = bts_read; |
| 762 | tracer->trace.write = bts_write; |
| 763 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 764 | /* Start tracing. */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 765 | ds_resume_bts(tracer); |
| 766 | |
| 767 | return tracer; |
| 768 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 769 | out_unlock: |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 770 | spin_unlock_irq(&ds_lock); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 771 | ds_put_context(tracer->ds.context); |
| 772 | out_tracer: |
| 773 | kfree(tracer); |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 774 | out_put_tracer: |
| 775 | put_tracer(task); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 776 | out: |
| 777 | return ERR_PTR(error); |
| 778 | } |
| 779 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 780 | struct bts_tracer *ds_request_bts_task(struct task_struct *task, |
| 781 | void *base, size_t size, |
| 782 | bts_ovfl_callback_t ovfl, |
| 783 | size_t th, unsigned int flags) |
| 784 | { |
| 785 | return ds_request_bts(task, 0, base, size, ovfl, th, flags); |
| 786 | } |
| 787 | |
| 788 | struct bts_tracer *ds_request_bts_cpu(int cpu, void *base, size_t size, |
| 789 | bts_ovfl_callback_t ovfl, |
| 790 | size_t th, unsigned int flags) |
| 791 | { |
| 792 | return ds_request_bts(NULL, cpu, base, size, ovfl, th, flags); |
| 793 | } |
| 794 | |
| 795 | static struct pebs_tracer *ds_request_pebs(struct task_struct *task, int cpu, |
| 796 | void *base, size_t size, |
| 797 | pebs_ovfl_callback_t ovfl, size_t th, |
| 798 | unsigned int flags) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 799 | { |
| 800 | struct pebs_tracer *tracer; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 801 | int error; |
| 802 | |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 803 | /* Buffer overflow notification is not yet implemented. */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 804 | error = -EOPNOTSUPP; |
| 805 | if (ovfl) |
| 806 | goto out; |
| 807 | |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 808 | error = get_tracer(task); |
| 809 | if (error < 0) |
| 810 | goto out; |
| 811 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 812 | error = -ENOMEM; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 813 | tracer = kzalloc(sizeof(*tracer), GFP_KERNEL); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 814 | if (!tracer) |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 815 | goto out_put_tracer; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 816 | tracer->ovfl = ovfl; |
| 817 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 818 | /* Do some more error checking and acquire a tracing context. */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 819 | error = ds_request(&tracer->ds, &tracer->trace.ds, |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 820 | ds_pebs, task, cpu, base, size, th); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 821 | if (error < 0) |
| 822 | goto out_tracer; |
| 823 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 824 | /* Claim the pebs part of the tracing context we acquired above. */ |
| 825 | spin_lock_irq(&ds_lock); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 826 | |
| 827 | error = -EPERM; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 828 | if (tracer->ds.context->pebs_master) |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 829 | goto out_unlock; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 830 | tracer->ds.context->pebs_master = tracer; |
| 831 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 832 | spin_unlock_irq(&ds_lock); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 833 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 834 | /* |
| 835 | * Now that we own the pebs part of the context, let's complete the |
| 836 | * initialization for that part. |
| 837 | */ |
| 838 | ds_init_ds_trace(&tracer->trace.ds, ds_pebs, base, size, th, flags); |
Markus Metzger | 73bf1b6 | 2009-03-05 08:57:21 +0100 | [diff] [blame] | 839 | ds_write_config(tracer->ds.context, &tracer->trace.ds, ds_pebs); |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 840 | ds_install_ds_area(tracer->ds.context); |
| 841 | |
| 842 | /* Start tracing. */ |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 843 | ds_resume_pebs(tracer); |
| 844 | |
| 845 | return tracer; |
| 846 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 847 | out_unlock: |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 848 | spin_unlock_irq(&ds_lock); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 849 | ds_put_context(tracer->ds.context); |
| 850 | out_tracer: |
| 851 | kfree(tracer); |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 852 | out_put_tracer: |
| 853 | put_tracer(task); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 854 | out: |
| 855 | return ERR_PTR(error); |
| 856 | } |
| 857 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 858 | struct pebs_tracer *ds_request_pebs_task(struct task_struct *task, |
| 859 | void *base, size_t size, |
| 860 | pebs_ovfl_callback_t ovfl, |
| 861 | size_t th, unsigned int flags) |
| 862 | { |
| 863 | return ds_request_pebs(task, 0, base, size, ovfl, th, flags); |
| 864 | } |
| 865 | |
| 866 | struct pebs_tracer *ds_request_pebs_cpu(int cpu, void *base, size_t size, |
| 867 | pebs_ovfl_callback_t ovfl, |
| 868 | size_t th, unsigned int flags) |
| 869 | { |
| 870 | return ds_request_pebs(NULL, cpu, base, size, ovfl, th, flags); |
| 871 | } |
| 872 | |
| 873 | static void ds_free_bts(struct bts_tracer *tracer) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 874 | { |
Markus Metzger | 8d99b3a | 2009-04-03 16:43:36 +0200 | [diff] [blame] | 875 | struct task_struct *task; |
| 876 | |
Markus Metzger | 8d99b3a | 2009-04-03 16:43:36 +0200 | [diff] [blame] | 877 | task = tracer->ds.context->task; |
| 878 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 879 | WARN_ON_ONCE(tracer->ds.context->bts_master != tracer); |
| 880 | tracer->ds.context->bts_master = NULL; |
| 881 | |
Markus Metzger | 8d99b3a | 2009-04-03 16:43:36 +0200 | [diff] [blame] | 882 | /* Make sure tracing stopped and the tracer is not in use. */ |
| 883 | if (task && (task != current)) |
| 884 | wait_task_context_switch(task); |
| 885 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 886 | ds_put_context(tracer->ds.context); |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 887 | put_tracer(task); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 888 | |
| 889 | kfree(tracer); |
| 890 | } |
| 891 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 892 | void ds_release_bts(struct bts_tracer *tracer) |
| 893 | { |
| 894 | might_sleep(); |
| 895 | |
| 896 | if (!tracer) |
| 897 | return; |
| 898 | |
| 899 | ds_suspend_bts(tracer); |
| 900 | ds_free_bts(tracer); |
| 901 | } |
| 902 | |
| 903 | int ds_release_bts_noirq(struct bts_tracer *tracer) |
| 904 | { |
| 905 | struct task_struct *task; |
| 906 | unsigned long irq; |
| 907 | int error; |
| 908 | |
| 909 | if (!tracer) |
| 910 | return 0; |
| 911 | |
| 912 | task = tracer->ds.context->task; |
| 913 | |
| 914 | local_irq_save(irq); |
| 915 | |
| 916 | error = -EPERM; |
| 917 | if (!task && |
| 918 | (tracer->ds.context->cpu != smp_processor_id())) |
| 919 | goto out; |
| 920 | |
| 921 | error = -EPERM; |
| 922 | if (task && (task != current)) |
| 923 | goto out; |
| 924 | |
| 925 | ds_suspend_bts_noirq(tracer); |
| 926 | ds_free_bts(tracer); |
| 927 | |
| 928 | error = 0; |
| 929 | out: |
| 930 | local_irq_restore(irq); |
| 931 | return error; |
| 932 | } |
| 933 | |
| 934 | static void update_task_debugctlmsr(struct task_struct *task, |
| 935 | unsigned long debugctlmsr) |
| 936 | { |
| 937 | task->thread.debugctlmsr = debugctlmsr; |
| 938 | |
| 939 | get_cpu(); |
| 940 | if (task == current) |
| 941 | update_debugctlmsr(debugctlmsr); |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 942 | put_cpu(); |
| 943 | } |
| 944 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 945 | void ds_suspend_bts(struct bts_tracer *tracer) |
| 946 | { |
| 947 | struct task_struct *task; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 948 | unsigned long debugctlmsr; |
| 949 | int cpu; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 950 | |
| 951 | if (!tracer) |
| 952 | return; |
| 953 | |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 954 | tracer->flags = 0; |
| 955 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 956 | task = tracer->ds.context->task; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 957 | cpu = tracer->ds.context->cpu; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 958 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 959 | WARN_ON(!task && irqs_disabled()); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 960 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 961 | debugctlmsr = (task ? |
| 962 | task->thread.debugctlmsr : |
| 963 | get_debugctlmsr_on_cpu(cpu)); |
| 964 | debugctlmsr &= ~BTS_CONTROL; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 965 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 966 | if (task) |
| 967 | update_task_debugctlmsr(task, debugctlmsr); |
| 968 | else |
| 969 | update_debugctlmsr_on_cpu(cpu, debugctlmsr); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 970 | } |
| 971 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 972 | int ds_suspend_bts_noirq(struct bts_tracer *tracer) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 973 | { |
| 974 | struct task_struct *task; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 975 | unsigned long debugctlmsr, irq; |
| 976 | int cpu, error = 0; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 977 | |
| 978 | if (!tracer) |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 979 | return 0; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 980 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 981 | tracer->flags = 0; |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 982 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 983 | task = tracer->ds.context->task; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 984 | cpu = tracer->ds.context->cpu; |
| 985 | |
| 986 | local_irq_save(irq); |
| 987 | |
| 988 | error = -EPERM; |
| 989 | if (!task && (cpu != smp_processor_id())) |
| 990 | goto out; |
| 991 | |
| 992 | debugctlmsr = (task ? |
| 993 | task->thread.debugctlmsr : |
| 994 | get_debugctlmsr()); |
| 995 | debugctlmsr &= ~BTS_CONTROL; |
| 996 | |
| 997 | if (task) |
| 998 | update_task_debugctlmsr(task, debugctlmsr); |
| 999 | else |
| 1000 | update_debugctlmsr(debugctlmsr); |
| 1001 | |
| 1002 | error = 0; |
| 1003 | out: |
| 1004 | local_irq_restore(irq); |
| 1005 | return error; |
| 1006 | } |
| 1007 | |
| 1008 | static unsigned long ds_bts_control(struct bts_tracer *tracer) |
| 1009 | { |
| 1010 | unsigned long control; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1011 | |
| 1012 | control = ds_cfg.ctl[dsf_bts]; |
| 1013 | if (!(tracer->trace.ds.flags & BTS_KERNEL)) |
| 1014 | control |= ds_cfg.ctl[dsf_bts_kernel]; |
| 1015 | if (!(tracer->trace.ds.flags & BTS_USER)) |
| 1016 | control |= ds_cfg.ctl[dsf_bts_user]; |
| 1017 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1018 | return control; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1019 | } |
| 1020 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1021 | void ds_resume_bts(struct bts_tracer *tracer) |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1022 | { |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 1023 | struct task_struct *task; |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1024 | unsigned long debugctlmsr; |
| 1025 | int cpu; |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 1026 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1027 | if (!tracer) |
| 1028 | return; |
| 1029 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1030 | tracer->flags = tracer->trace.ds.flags; |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 1031 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1032 | task = tracer->ds.context->task; |
| 1033 | cpu = tracer->ds.context->cpu; |
| 1034 | |
| 1035 | WARN_ON(!task && irqs_disabled()); |
| 1036 | |
| 1037 | debugctlmsr = (task ? |
| 1038 | task->thread.debugctlmsr : |
| 1039 | get_debugctlmsr_on_cpu(cpu)); |
| 1040 | debugctlmsr |= ds_bts_control(tracer); |
| 1041 | |
| 1042 | if (task) |
| 1043 | update_task_debugctlmsr(task, debugctlmsr); |
| 1044 | else |
| 1045 | update_debugctlmsr_on_cpu(cpu, debugctlmsr); |
| 1046 | } |
| 1047 | |
| 1048 | int ds_resume_bts_noirq(struct bts_tracer *tracer) |
| 1049 | { |
| 1050 | struct task_struct *task; |
| 1051 | unsigned long debugctlmsr, irq; |
| 1052 | int cpu, error = 0; |
| 1053 | |
| 1054 | if (!tracer) |
| 1055 | return 0; |
| 1056 | |
| 1057 | tracer->flags = tracer->trace.ds.flags; |
| 1058 | |
| 1059 | task = tracer->ds.context->task; |
| 1060 | cpu = tracer->ds.context->cpu; |
| 1061 | |
| 1062 | local_irq_save(irq); |
| 1063 | |
| 1064 | error = -EPERM; |
| 1065 | if (!task && (cpu != smp_processor_id())) |
| 1066 | goto out; |
| 1067 | |
| 1068 | debugctlmsr = (task ? |
| 1069 | task->thread.debugctlmsr : |
| 1070 | get_debugctlmsr()); |
| 1071 | debugctlmsr |= ds_bts_control(tracer); |
| 1072 | |
| 1073 | if (task) |
| 1074 | update_task_debugctlmsr(task, debugctlmsr); |
| 1075 | else |
| 1076 | update_debugctlmsr(debugctlmsr); |
| 1077 | |
| 1078 | error = 0; |
| 1079 | out: |
| 1080 | local_irq_restore(irq); |
| 1081 | return error; |
| 1082 | } |
| 1083 | |
| 1084 | static void ds_free_pebs(struct pebs_tracer *tracer) |
| 1085 | { |
| 1086 | struct task_struct *task; |
| 1087 | |
| 1088 | task = tracer->ds.context->task; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1089 | |
| 1090 | WARN_ON_ONCE(tracer->ds.context->pebs_master != tracer); |
| 1091 | tracer->ds.context->pebs_master = NULL; |
| 1092 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1093 | ds_put_context(tracer->ds.context); |
Markus Metzger | 38f8011 | 2009-04-03 16:43:37 +0200 | [diff] [blame] | 1094 | put_tracer(task); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1095 | |
| 1096 | kfree(tracer); |
| 1097 | } |
| 1098 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1099 | void ds_release_pebs(struct pebs_tracer *tracer) |
| 1100 | { |
| 1101 | might_sleep(); |
| 1102 | |
| 1103 | if (!tracer) |
| 1104 | return; |
| 1105 | |
| 1106 | ds_suspend_pebs(tracer); |
| 1107 | ds_free_pebs(tracer); |
| 1108 | } |
| 1109 | |
| 1110 | int ds_release_pebs_noirq(struct pebs_tracer *tracer) |
| 1111 | { |
| 1112 | struct task_struct *task; |
| 1113 | unsigned long irq; |
| 1114 | int error; |
| 1115 | |
| 1116 | if (!tracer) |
| 1117 | return 0; |
| 1118 | |
| 1119 | task = tracer->ds.context->task; |
| 1120 | |
| 1121 | local_irq_save(irq); |
| 1122 | |
| 1123 | error = -EPERM; |
| 1124 | if (!task && |
| 1125 | (tracer->ds.context->cpu != smp_processor_id())) |
| 1126 | goto out; |
| 1127 | |
| 1128 | error = -EPERM; |
| 1129 | if (task && (task != current)) |
| 1130 | goto out; |
| 1131 | |
| 1132 | ds_suspend_pebs_noirq(tracer); |
| 1133 | ds_free_pebs(tracer); |
| 1134 | |
| 1135 | error = 0; |
| 1136 | out: |
| 1137 | local_irq_restore(irq); |
| 1138 | return error; |
| 1139 | } |
| 1140 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1141 | void ds_suspend_pebs(struct pebs_tracer *tracer) |
| 1142 | { |
| 1143 | |
| 1144 | } |
| 1145 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1146 | int ds_suspend_pebs_noirq(struct pebs_tracer *tracer) |
| 1147 | { |
| 1148 | return 0; |
| 1149 | } |
| 1150 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1151 | void ds_resume_pebs(struct pebs_tracer *tracer) |
| 1152 | { |
| 1153 | |
| 1154 | } |
| 1155 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1156 | int ds_resume_pebs_noirq(struct pebs_tracer *tracer) |
| 1157 | { |
| 1158 | return 0; |
| 1159 | } |
| 1160 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1161 | const struct bts_trace *ds_read_bts(struct bts_tracer *tracer) |
| 1162 | { |
| 1163 | if (!tracer) |
| 1164 | return NULL; |
| 1165 | |
| 1166 | ds_read_config(tracer->ds.context, &tracer->trace.ds, ds_bts); |
| 1167 | return &tracer->trace; |
| 1168 | } |
| 1169 | |
| 1170 | const struct pebs_trace *ds_read_pebs(struct pebs_tracer *tracer) |
| 1171 | { |
| 1172 | if (!tracer) |
| 1173 | return NULL; |
| 1174 | |
| 1175 | ds_read_config(tracer->ds.context, &tracer->trace.ds, ds_pebs); |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1176 | |
| 1177 | tracer->trace.counters = ds_cfg.nr_counter_reset; |
| 1178 | memcpy(tracer->trace.counter_reset, |
| 1179 | tracer->ds.context->ds + |
| 1180 | (NUM_DS_PTR_FIELDS * ds_cfg.sizeof_ptr_field), |
| 1181 | ds_cfg.nr_counter_reset * PEBS_RESET_FIELD_SIZE); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1182 | |
| 1183 | return &tracer->trace; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1184 | } |
| 1185 | |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1186 | int ds_reset_bts(struct bts_tracer *tracer) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1187 | { |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1188 | if (!tracer) |
| 1189 | return -EINVAL; |
| 1190 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1191 | tracer->trace.ds.top = tracer->trace.ds.begin; |
| 1192 | |
| 1193 | ds_set(tracer->ds.context->ds, ds_bts, ds_index, |
| 1194 | (unsigned long)tracer->trace.ds.top); |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1195 | |
| 1196 | return 0; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1197 | } |
| 1198 | |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1199 | int ds_reset_pebs(struct pebs_tracer *tracer) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1200 | { |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1201 | if (!tracer) |
| 1202 | return -EINVAL; |
| 1203 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1204 | tracer->trace.ds.top = tracer->trace.ds.begin; |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1205 | |
Markus Metzger | 608780a | 2009-04-03 16:43:50 +0200 | [diff] [blame] | 1206 | ds_set(tracer->ds.context->ds, ds_pebs, ds_index, |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1207 | (unsigned long)tracer->trace.ds.top); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1208 | |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1209 | return 0; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1210 | } |
| 1211 | |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1212 | int ds_set_pebs_reset(struct pebs_tracer *tracer, |
| 1213 | unsigned int counter, u64 value) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1214 | { |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1215 | if (!tracer) |
| 1216 | return -EINVAL; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1217 | |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1218 | if (ds_cfg.nr_counter_reset < counter) |
| 1219 | return -EINVAL; |
| 1220 | |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1221 | *(u64 *)(tracer->ds.context->ds + |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1222 | (NUM_DS_PTR_FIELDS * ds_cfg.sizeof_ptr_field) + |
| 1223 | (counter * PEBS_RESET_FIELD_SIZE)) = value; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1224 | |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1225 | return 0; |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1226 | } |
| 1227 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1228 | static const struct ds_configuration ds_cfg_netburst = { |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1229 | .name = "Netburst", |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1230 | .ctl[dsf_bts] = (1 << 2) | (1 << 3), |
| 1231 | .ctl[dsf_bts_kernel] = (1 << 5), |
| 1232 | .ctl[dsf_bts_user] = (1 << 6), |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1233 | .nr_counter_reset = 1, |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1234 | }; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1235 | static const struct ds_configuration ds_cfg_pentium_m = { |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1236 | .name = "Pentium M", |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1237 | .ctl[dsf_bts] = (1 << 6) | (1 << 7), |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1238 | .nr_counter_reset = 1, |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1239 | }; |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1240 | static const struct ds_configuration ds_cfg_core2_atom = { |
| 1241 | .name = "Core 2/Atom", |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1242 | .ctl[dsf_bts] = (1 << 6) | (1 << 7), |
| 1243 | .ctl[dsf_bts_kernel] = (1 << 9), |
| 1244 | .ctl[dsf_bts_user] = (1 << 10), |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1245 | .nr_counter_reset = 1, |
| 1246 | }; |
| 1247 | static const struct ds_configuration ds_cfg_core_i7 = { |
| 1248 | .name = "Core i7", |
| 1249 | .ctl[dsf_bts] = (1 << 6) | (1 << 7), |
| 1250 | .ctl[dsf_bts_kernel] = (1 << 9), |
| 1251 | .ctl[dsf_bts_user] = (1 << 10), |
| 1252 | .nr_counter_reset = 4, |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1253 | }; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1254 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1255 | static void |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1256 | ds_configure(const struct ds_configuration *cfg, |
| 1257 | struct cpuinfo_x86 *cpu) |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1258 | { |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1259 | unsigned long nr_pebs_fields = 0; |
| 1260 | |
| 1261 | printk(KERN_INFO "[ds] using %s configuration\n", cfg->name); |
| 1262 | |
| 1263 | #ifdef __i386__ |
| 1264 | nr_pebs_fields = 10; |
| 1265 | #else |
| 1266 | nr_pebs_fields = 18; |
| 1267 | #endif |
| 1268 | |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1269 | /* |
| 1270 | * Starting with version 2, architectural performance |
| 1271 | * monitoring supports a format specifier. |
| 1272 | */ |
| 1273 | if ((cpuid_eax(0xa) & 0xff) > 1) { |
| 1274 | unsigned long perf_capabilities, format; |
| 1275 | |
| 1276 | rdmsrl(MSR_IA32_PERF_CAPABILITIES, perf_capabilities); |
| 1277 | |
| 1278 | format = (perf_capabilities >> 8) & 0xf; |
| 1279 | |
| 1280 | switch (format) { |
| 1281 | case 0: |
| 1282 | nr_pebs_fields = 18; |
| 1283 | break; |
| 1284 | case 1: |
| 1285 | nr_pebs_fields = 22; |
| 1286 | break; |
| 1287 | default: |
| 1288 | printk(KERN_INFO |
| 1289 | "[ds] unknown PEBS format: %lu\n", format); |
| 1290 | nr_pebs_fields = 0; |
| 1291 | break; |
| 1292 | } |
| 1293 | } |
| 1294 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1295 | memset(&ds_cfg, 0, sizeof(ds_cfg)); |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1296 | ds_cfg = *cfg; |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1297 | |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1298 | ds_cfg.sizeof_ptr_field = |
| 1299 | (cpu_has(cpu, X86_FEATURE_DTES64) ? 8 : 4); |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1300 | |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1301 | ds_cfg.sizeof_rec[ds_bts] = ds_cfg.sizeof_ptr_field * 3; |
| 1302 | ds_cfg.sizeof_rec[ds_pebs] = ds_cfg.sizeof_ptr_field * nr_pebs_fields; |
| 1303 | |
| 1304 | if (!cpu_has(cpu, X86_FEATURE_BTS)) { |
| 1305 | ds_cfg.sizeof_rec[ds_bts] = 0; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1306 | printk(KERN_INFO "[ds] bts not available\n"); |
| 1307 | } |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1308 | if (!cpu_has(cpu, X86_FEATURE_PEBS)) { |
| 1309 | ds_cfg.sizeof_rec[ds_pebs] = 0; |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1310 | printk(KERN_INFO "[ds] pebs not available\n"); |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1311 | } |
| 1312 | |
| 1313 | printk(KERN_INFO "[ds] sizes: address: %u bit, ", |
| 1314 | 8 * ds_cfg.sizeof_ptr_field); |
| 1315 | printk("bts/pebs record: %u/%u bytes\n", |
| 1316 | ds_cfg.sizeof_rec[ds_bts], ds_cfg.sizeof_rec[ds_pebs]); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1317 | |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1318 | WARN_ON_ONCE(MAX_PEBS_COUNTERS < ds_cfg.nr_counter_reset); |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1319 | } |
| 1320 | |
| 1321 | void __cpuinit ds_init_intel(struct cpuinfo_x86 *c) |
| 1322 | { |
Markus Metzger | ee81151 | 2009-04-03 16:43:47 +0200 | [diff] [blame] | 1323 | /* Only configure the first cpu. Others are identical. */ |
| 1324 | if (ds_cfg.name) |
| 1325 | return; |
| 1326 | |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1327 | switch (c->x86) { |
| 1328 | case 0x6: |
| 1329 | switch (c->x86_model) { |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1330 | case 0x9: |
| 1331 | case 0xd: /* Pentium M */ |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1332 | ds_configure(&ds_cfg_pentium_m, c); |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1333 | break; |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1334 | case 0xf: |
| 1335 | case 0x17: /* Core2 */ |
| 1336 | case 0x1c: /* Atom */ |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1337 | ds_configure(&ds_cfg_core2_atom, c); |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1338 | break; |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 1339 | case 0x1a: /* Core i7 */ |
Markus Metzger | 017bc61 | 2009-04-03 16:43:52 +0200 | [diff] [blame] | 1340 | ds_configure(&ds_cfg_core_i7, c); |
| 1341 | break; |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1342 | default: |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 1343 | /* Sorry, don't know about them. */ |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1344 | break; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1345 | } |
| 1346 | break; |
Markus Metzger | ba2607f | 2009-01-19 10:38:35 +0100 | [diff] [blame] | 1347 | case 0xf: |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1348 | switch (c->x86_model) { |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1349 | case 0x0: |
| 1350 | case 0x1: |
| 1351 | case 0x2: /* Netburst */ |
Markus Metzger | bc44fb5 | 2009-03-13 10:42:18 +0100 | [diff] [blame] | 1352 | ds_configure(&ds_cfg_netburst, c); |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1353 | break; |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1354 | default: |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 1355 | /* Sorry, don't know about them. */ |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1356 | break; |
| 1357 | } |
| 1358 | break; |
| 1359 | default: |
Markus Metzger | b8e4719 | 2009-03-13 10:46:42 +0100 | [diff] [blame] | 1360 | /* Sorry, don't know about them. */ |
Markus Metzger | eee3af4 | 2008-01-30 13:31:09 +0100 | [diff] [blame] | 1361 | break; |
| 1362 | } |
| 1363 | } |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1364 | |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 1365 | static inline void ds_take_timestamp(struct ds_context *context, |
| 1366 | enum bts_qualifier qualifier, |
| 1367 | struct task_struct *task) |
| 1368 | { |
| 1369 | struct bts_tracer *tracer = context->bts_master; |
| 1370 | struct bts_struct ts; |
| 1371 | |
| 1372 | /* Prevent compilers from reading the tracer pointer twice. */ |
| 1373 | barrier(); |
| 1374 | |
| 1375 | if (!tracer || !(tracer->flags & BTS_TIMESTAMPS)) |
| 1376 | return; |
| 1377 | |
| 1378 | memset(&ts, 0, sizeof(ts)); |
Markus Metzger | 15879d0 | 2009-04-03 16:43:38 +0200 | [diff] [blame] | 1379 | ts.qualifier = qualifier; |
| 1380 | ts.variant.event.clock = trace_clock_global(); |
| 1381 | ts.variant.event.pid = task->pid; |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 1382 | |
| 1383 | bts_write(tracer, &ts); |
| 1384 | } |
| 1385 | |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1386 | /* |
| 1387 | * Change the DS configuration from tracing prev to tracing next. |
| 1388 | */ |
| 1389 | void ds_switch_to(struct task_struct *prev, struct task_struct *next) |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1390 | { |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 1391 | struct ds_context *prev_ctx = prev->thread.ds_ctx; |
| 1392 | struct ds_context *next_ctx = next->thread.ds_ctx; |
| 1393 | unsigned long debugctlmsr = next->thread.debugctlmsr; |
| 1394 | |
| 1395 | /* Make sure all data is read before we start. */ |
| 1396 | barrier(); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1397 | |
| 1398 | if (prev_ctx) { |
| 1399 | update_debugctlmsr(0); |
| 1400 | |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 1401 | ds_take_timestamp(prev_ctx, bts_task_departs, prev); |
Markus Metzger | ca0002a | 2008-11-25 09:01:25 +0100 | [diff] [blame] | 1402 | } |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1403 | |
| 1404 | if (next_ctx) { |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 1405 | ds_take_timestamp(next_ctx, bts_task_arrives, next); |
Markus Metzger | c272477 | 2008-12-11 13:49:59 +0100 | [diff] [blame] | 1406 | |
| 1407 | wrmsrl(MSR_IA32_DS_AREA, (unsigned long)next_ctx->ds); |
| 1408 | } |
| 1409 | |
Markus Metzger | cac94f9 | 2009-04-03 16:43:33 +0200 | [diff] [blame] | 1410 | update_debugctlmsr(debugctlmsr); |
Markus Metzger | 93fa763 | 2008-04-08 11:01:58 +0200 | [diff] [blame] | 1411 | } |
Markus Metzger | bf53de9 | 2008-12-19 15:10:24 +0100 | [diff] [blame] | 1412 | |
Markus Metzger | de79f54 | 2009-04-03 16:43:40 +0200 | [diff] [blame] | 1413 | static __init int ds_selftest(void) |
| 1414 | { |
| 1415 | if (ds_cfg.sizeof_rec[ds_bts]) { |
| 1416 | int error; |
| 1417 | |
| 1418 | error = ds_selftest_bts(); |
| 1419 | if (error) { |
| 1420 | WARN(1, "[ds] selftest failed. disabling bts.\n"); |
| 1421 | ds_cfg.sizeof_rec[ds_bts] = 0; |
| 1422 | } |
| 1423 | } |
| 1424 | |
| 1425 | if (ds_cfg.sizeof_rec[ds_pebs]) { |
| 1426 | int error; |
| 1427 | |
| 1428 | error = ds_selftest_pebs(); |
| 1429 | if (error) { |
| 1430 | WARN(1, "[ds] selftest failed. disabling pebs.\n"); |
| 1431 | ds_cfg.sizeof_rec[ds_pebs] = 0; |
| 1432 | } |
| 1433 | } |
| 1434 | |
| 1435 | return 0; |
| 1436 | } |
| 1437 | device_initcall(ds_selftest); |