diff options
Diffstat (limited to 'cpus.c')
| -rw-r--r-- | cpus.c | 72 |
1 files changed, 0 insertions, 72 deletions
@@ -166,78 +166,6 @@ typedef struct TimersState { static TimersState timers_state; bool mttcg_enabled; -/* - * We default to false if we know other options have been enabled - * which are currently incompatible with MTTCG. Otherwise when each - * guest (target) has been updated to support: - * - atomic instructions - * - memory ordering primitives (barriers) - * they can set the appropriate CONFIG flags in ${target}-softmmu.mak - * - * Once a guest architecture has been converted to the new primitives - * there are two remaining limitations to check. - * - * - The guest can't be oversized (e.g. 64 bit guest on 32 bit host) - * - The host must have a stronger memory order than the guest - * - * It may be possible in future to support strong guests on weak hosts - * but that will require tagging all load/stores in a guest with their - * implicit memory order requirements which would likely slow things - * down a lot. - */ - -static bool check_tcg_memory_orders_compatible(void) -{ -#if defined(TCG_GUEST_DEFAULT_MO) && defined(TCG_TARGET_DEFAULT_MO) - return (TCG_GUEST_DEFAULT_MO & ~TCG_TARGET_DEFAULT_MO) == 0; -#else - return false; -#endif -} - -static bool default_mttcg_enabled(void) -{ - if (use_icount || TCG_OVERSIZED_GUEST) { - return false; - } else { -#ifdef TARGET_SUPPORTS_MTTCG - return check_tcg_memory_orders_compatible(); -#else - return false; -#endif - } -} - -void qemu_tcg_configure(QemuOpts *opts, Error **errp) -{ - const char *t = qemu_opt_get(opts, "thread"); - if (t) { - if (strcmp(t, "multi") == 0) { - if (TCG_OVERSIZED_GUEST) { - error_setg(errp, "No MTTCG when guest word size > hosts"); - } else if (use_icount) { - error_setg(errp, "No MTTCG when icount is enabled"); - } else { -#ifndef TARGET_SUPPORTS_MTTCG - warn_report("Guest not yet converted to MTTCG - " - "you may get unexpected results"); -#endif - if (!check_tcg_memory_orders_compatible()) { - warn_report("Guest expects a stronger memory ordering " - "than the host provides"); - error_printf("This may cause strange/hard to debug errors\n"); - } - mttcg_enabled = true; - } - } else if (strcmp(t, "single") == 0) { - mttcg_enabled = false; - } else { - error_setg(errp, "Invalid 'thread' setting %s", t); - } - } else { - mttcg_enabled = default_mttcg_enabled(); - } -} /* The current number of executed instructions is based on what we * originally budgeted minus the current state of the decrementing |