We need not call tb_flush once per cpu, only once per vmload. By moving the call from cpu_common_post_load to a tcg-specific vm_change_state_handler, we do even better than that: we only flush when called from HMP triggered loadvm, when we had old state to flush.
Reviewed-by: Philippe Mathieu-Daudé <[email protected]> Reviewed-by: Pierrick Bouvier <[email protected]> Signed-off-by: Richard Henderson <[email protected]> --- accel/tcg/tcg-all.c | 21 +++++++++++++++++++++ hw/core/cpu-system.c | 9 --------- 2 files changed, 21 insertions(+), 9 deletions(-) diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c index 5125e1a4e2..18ea0c58b0 100644 --- a/accel/tcg/tcg-all.c +++ b/accel/tcg/tcg-all.c @@ -38,6 +38,8 @@ #include "qemu/target-info.h" #ifndef CONFIG_USER_ONLY #include "hw/boards.h" +#include "exec/tb-flush.h" +#include "system/runstate.h" #endif #include "accel/accel-ops.h" #include "accel/accel-cpu-ops.h" @@ -82,6 +84,23 @@ static void tcg_accel_instance_init(Object *obj) bool one_insn_per_tb; +#ifndef CONFIG_USER_ONLY +static void tcg_vm_change_state(void *opaque, bool running, RunState state) +{ + if (state == RUN_STATE_RESTORE_VM) { + /* + * loadvm will update the content of RAM, bypassing the usual + * mechanisms that ensure we flush TBs for writes to memory + * we've translated code from, so we must flush all TBs. + * + * vm_stop() has just stopped all cpus, so we are exclusive. + */ + assert(!running); + tb_flush__exclusive_or_serial(); + } +} +#endif + static int tcg_init_machine(AccelState *as, MachineState *ms) { TCGState *s = TCG_STATE(as); @@ -124,6 +143,8 @@ static int tcg_init_machine(AccelState *as, MachineState *ms) default: g_assert_not_reached(); } + + qemu_add_vm_change_state_handler(tcg_vm_change_state, NULL); #endif tcg_allowed = true; diff --git a/hw/core/cpu-system.c b/hw/core/cpu-system.c index 09c928c1f9..f601a083d1 100644 --- a/hw/core/cpu-system.c +++ b/hw/core/cpu-system.c @@ -23,7 +23,6 @@ #include "system/address-spaces.h" #include "exec/cputlb.h" #include "system/memory.h" -#include "exec/tb-flush.h" #include "qemu/target-info.h" #include "hw/qdev-core.h" #include "hw/qdev-properties.h" @@ -207,14 +206,6 @@ static int cpu_common_post_load(void *opaque, int version_id) cpu_reset_interrupt(cpu, 0x01); tlb_flush(cpu); - - /* - * loadvm has just updated the content of RAM, bypassing the - * usual mechanisms that ensure we flush TBs for writes to - * memory we've translated code from. So we must flush all TBs, - * which will now be stale. - */ - tb_flush(cpu); } return 0; -- 2.43.0
