accel/tcg/tcg-all.c

   1 /*
   2  * QEMU System Emulator, accelerator interfaces
   3  *
   4  * Copyright (c) 2003-2008 Fabrice Bellard
   5  * Copyright (c) 2014 Red Hat Inc.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #include "qemu/osdep.h"
  27 #include "sysemu/tcg.h"
  28 #include "exec/replay-core.h"
  29 #include "sysemu/cpu-timers.h"
  30 #include "tcg/tcg.h"
  31 #include "tcg/oversized-guest.h"
  32 #include "qapi/error.h"
  33 #include "qemu/error-report.h"
  34 #include "qemu/accel.h"
  35 #include "qemu/atomic.h"
  36 #include "qapi/qapi-builtin-visit.h"
  37 #include "qemu/units.h"
  38 #if !defined(CONFIG_USER_ONLY)
  39 #include "hw/boards.h"
  40 #endif
  41 #include "internal.h"
  42
  43 struct TCGState {
  44     AccelState parent_obj;
  45
  46     bool mttcg_enabled;
  47     bool one_insn_per_tb;
  48     int splitwx_enabled;
  49     unsigned long tb_size;
  50 };
  51 typedef struct TCGState TCGState;
  52
  53 #define TYPE_TCG_ACCEL ACCEL_CLASS_NAME("tcg")
  54
  55 DECLARE_INSTANCE_CHECKER(TCGState, TCG_STATE,
  56                          TYPE_TCG_ACCEL)
  57
  58 /*
  59  * We default to false if we know other options have been enabled
  60  * which are currently incompatible with MTTCG. Otherwise when each
  61  * guest (target) has been updated to support:
  62  *   - atomic instructions
  63  *   - memory ordering primitives (barriers)
  64  * they can set the appropriate CONFIG flags in ${target}-softmmu.mak
  65  *
  66  * Once a guest architecture has been converted to the new primitives
  67  * there is one remaining limitation to check:
  68  *   - The guest can't be oversized (e.g. 64 bit guest on 32 bit host)
  69  */
  70
  71 static bool default_mttcg_enabled(void)
  72 {
  73     if (icount_enabled() || TCG_OVERSIZED_GUEST) {
  74         return false;
  75     }
  76 #ifdef TARGET_SUPPORTS_MTTCG
  77 # ifndef TCG_GUEST_DEFAULT_MO
  78 #  error "TARGET_SUPPORTS_MTTCG without TCG_GUEST_DEFAULT_MO"
  79 # endif
  80     return true;
  81 #else
  82     return false;
  83 #endif
  84 }
  85
  86 static void tcg_accel_instance_init(Object *obj)
  87 {
  88     TCGState *s = TCG_STATE(obj);
  89
  90     s->mttcg_enabled = default_mttcg_enabled();
  91
  92     /* If debugging enabled, default "auto on", otherwise off. */
  93 #if defined(CONFIG_DEBUG_TCG) && !defined(CONFIG_USER_ONLY)
  94     s->splitwx_enabled = -1;
  95 #else
  96     s->splitwx_enabled = 0;
  97 #endif
  98 }
  99
 100 bool mttcg_enabled;
 101 bool one_insn_per_tb;
 102
 103 static int tcg_init_machine(MachineState *ms)
 104 {
 105     TCGState *s = TCG_STATE(current_accel());
 106 #ifdef CONFIG_USER_ONLY
 107     unsigned max_cpus = 1;
 108 #else
 109     unsigned max_cpus = ms->smp.max_cpus;
 110 #endif
 111
 112     tcg_allowed = true;
 113     mttcg_enabled = s->mttcg_enabled;
 114
 115     page_init();
 116     tb_htable_init();
 117     tcg_init(s->tb_size * MiB, s->splitwx_enabled, max_cpus);
 118
 119 #if defined(CONFIG_SOFTMMU)
 120     /*
 121      * There's no guest base to take into account, so go ahead and
 122      * initialize the prologue now.
 123      */
 124     tcg_prologue_init(tcg_ctx);
 125 #endif
 126
 127     return 0;
 128 }
 129
 130 static char *tcg_get_thread(Object *obj, Error **errp)
 131 {
 132     TCGState *s = TCG_STATE(obj);
 133
 134     return g_strdup(s->mttcg_enabled ? "multi" : "single");
 135 }
 136
 137 static void tcg_set_thread(Object *obj, const char *value, Error **errp)
 138 {
 139     TCGState *s = TCG_STATE(obj);
 140
 141     if (strcmp(value, "multi") == 0) {
 142         if (TCG_OVERSIZED_GUEST) {
 143             error_setg(errp, "No MTTCG when guest word size > hosts");
 144         } else if (icount_enabled()) {
 145             error_setg(errp, "No MTTCG when icount is enabled");
 146         } else {
 147 #ifndef TARGET_SUPPORTS_MTTCG
 148             warn_report("Guest not yet converted to MTTCG - "
 149                         "you may get unexpected results");
 150 #endif
 151             s->mttcg_enabled = true;
 152         }
 153     } else if (strcmp(value, "single") == 0) {
 154         s->mttcg_enabled = false;
 155     } else {
 156         error_setg(errp, "Invalid 'thread' setting %s", value);
 157     }
 158 }
 159
 160 static void tcg_get_tb_size(Object *obj, Visitor *v,
 161                             const char *name, void *opaque,
 162                             Error **errp)
 163 {
 164     TCGState *s = TCG_STATE(obj);
 165     uint32_t value = s->tb_size;
 166
 167     visit_type_uint32(v, name, &value, errp);
 168 }
 169
 170 static void tcg_set_tb_size(Object *obj, Visitor *v,
 171                             const char *name, void *opaque,
 172                             Error **errp)
 173 {
 174     TCGState *s = TCG_STATE(obj);
 175     uint32_t value;
 176
 177     if (!visit_type_uint32(v, name, &value, errp)) {
 178         return;
 179     }
 180
 181     s->tb_size = value;
 182 }
 183
 184 static bool tcg_get_splitwx(Object *obj, Error **errp)
 185 {
 186     TCGState *s = TCG_STATE(obj);
 187     return s->splitwx_enabled;
 188 }
 189
 190 static void tcg_set_splitwx(Object *obj, bool value, Error **errp)
 191 {
 192     TCGState *s = TCG_STATE(obj);
 193     s->splitwx_enabled = value;
 194 }
 195
 196 static bool tcg_get_one_insn_per_tb(Object *obj, Error **errp)
 197 {
 198     TCGState *s = TCG_STATE(obj);
 199     return s->one_insn_per_tb;
 200 }
 201
 202 static void tcg_set_one_insn_per_tb(Object *obj, bool value, Error **errp)
 203 {
 204     TCGState *s = TCG_STATE(obj);
 205     s->one_insn_per_tb = value;
 206     /* Set the global also: this changes the behaviour */
 207     qatomic_set(&one_insn_per_tb, value);
 208 }
 209
 210 static int tcg_gdbstub_supported_sstep_flags(void)
 211 {
 212     /*
 213      * In replay mode all events will come from the log and can't be
 214      * suppressed otherwise we would break determinism. However as those
 215      * events are tied to the number of executed instructions we won't see
 216      * them occurring every time we single step.
 217      */
 218     if (replay_mode != REPLAY_MODE_NONE) {
 219         return SSTEP_ENABLE;
 220     } else {
 221         return SSTEP_ENABLE | SSTEP_NOIRQ | SSTEP_NOTIMER;
 222     }
 223 }
 224
 225 static void tcg_accel_class_init(ObjectClass *oc, void *data)
 226 {
 227     AccelClass *ac = ACCEL_CLASS(oc);
 228     ac->name = "tcg";
 229     ac->init_machine = tcg_init_machine;
 230     ac->allowed = &tcg_allowed;
 231     ac->gdbstub_supported_sstep_flags = tcg_gdbstub_supported_sstep_flags;
 232
 233     object_class_property_add_str(oc, "thread",
 234                                   tcg_get_thread,
 235                                   tcg_set_thread);
 236
 237     object_class_property_add(oc, "tb-size", "int",
 238         tcg_get_tb_size, tcg_set_tb_size,
 239         NULL, NULL);
 240     object_class_property_set_description(oc, "tb-size",
 241         "TCG translation block cache size");
 242
 243     object_class_property_add_bool(oc, "split-wx",
 244         tcg_get_splitwx, tcg_set_splitwx);
 245     object_class_property_set_description(oc, "split-wx",
 246         "Map jit pages into separate RW and RX regions");
 247
 248     object_class_property_add_bool(oc, "one-insn-per-tb",
 249                                    tcg_get_one_insn_per_tb,
 250                                    tcg_set_one_insn_per_tb);
 251     object_class_property_set_description(oc, "one-insn-per-tb",
 252         "Only put one guest insn in each translation block");
 253 }
 254
 255 static const TypeInfo tcg_accel_type = {
 256     .name = TYPE_TCG_ACCEL,
 257     .parent = TYPE_ACCEL,
 258     .instance_init = tcg_accel_instance_init,
 259     .class_init = tcg_accel_class_init,
 260     .instance_size = sizeof(TCGState),
 261 };
 262 module_obj(TYPE_TCG_ACCEL);
 263
 264 static void register_accel_types(void)
 265 {
 266     type_register_static(&tcg_accel_type);
 267 }
 268
 269 type_init(register_accel_types);