From: Philippe Mathieu-Daudé <phi...@linaro.org>
Use the OnOffAuto type as 3-state.
Since the TCGState instance is zero-initialized, the
mttcg_enabled is initialzed as AUTO (ON_OFF_AUTO_AUTO).
In tcg_init_machine(), if mttcg_enabled is still AUTO,
set a default value (effectively inlining the
default_mttcg_enabled() method content).
In the tcg_get_thread() getter, consider AUTO / OFF states
as "single", otherwise ON is "multi".
Reviewed-by: Anton Johansson <a...@rev.ng>
Reviewed-by: Richard Henderson <richard.hender...@linaro.org>
Signed-off-by: Philippe Mathieu-Daudé <phi...@linaro.org>
Signed-off-by: Richard Henderson <richard.hender...@linaro.org>
---
accel/tcg/tcg-all.c | 74 ++++++++++++++++++++++-----------------------
1 file changed, 36 insertions(+), 38 deletions(-)
diff --git a/accel/tcg/tcg-all.c b/accel/tcg/tcg-all.c
index b754f92905..fa77a4c5a2 100644
--- a/accel/tcg/tcg-all.c
+++ b/accel/tcg/tcg-all.c
@@ -32,6 +32,7 @@
#include "qemu/error-report.h"
#include "qemu/accel.h"
#include "qemu/atomic.h"
+#include "qapi/qapi-types-common.h"
#include "qapi/qapi-builtin-visit.h"
#include "qemu/units.h"
#if defined(CONFIG_USER_ONLY)
@@ -47,7 +48,7 @@
struct TCGState {
AccelState parent_obj;
- bool mttcg_enabled;
+ OnOffAuto mttcg_enabled;
bool one_insn_per_tb;
int splitwx_enabled;
unsigned long tb_size;
@@ -63,41 +64,14 @@ DECLARE_INSTANCE_CHECKER(TCGState, TCG_STATE,
bool qemu_tcg_mttcg_enabled(void)
{
TCGState *s = TCG_STATE(current_accel());
- return s->mttcg_enabled;
+ return s->mttcg_enabled == ON_OFF_AUTO_ON;
}
#endif /* !CONFIG_USER_ONLY */
-/*
- * 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 is one remaining limitation to check:
- * - The guest can't be oversized (e.g. 64 bit guest on 32 bit host)
- */
-
-static bool default_mttcg_enabled(void)
-{
- if (icount_enabled()) {
- return false;
- }
-#ifdef TARGET_SUPPORTS_MTTCG
- return true;
-#else
- return false;
-#endif
-}
-
static void tcg_accel_instance_init(Object *obj)
{
TCGState *s = TCG_STATE(obj);
- s->mttcg_enabled = default_mttcg_enabled();
-
/* If debugging enabled, default "auto on", otherwise off. */
#if defined(CONFIG_DEBUG_TCG) && !defined(CONFIG_USER_ONLY)
s->splitwx_enabled = -1;
@@ -113,16 +87,40 @@ static int tcg_init_machine(MachineState *ms)
TCGState *s = TCG_STATE(current_accel());
unsigned max_threads = 1;
+#ifndef CONFIG_USER_ONLY
+# ifdef TARGET_SUPPORTS_MTTCG
+ bool mttcg_supported = true;
+# else
+ bool mttcg_supported = false;
+# endif
+ if (s->mttcg_enabled == ON_OFF_AUTO_AUTO) {
+ /*
+ * 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 is one remaining limitation to check:
+ * - The guest can't be oversized (e.g. 64 bit guest on 32 bit host)
+ */
+ if (mttcg_supported && !icount_enabled()) {
+ s->mttcg_enabled = ON_OFF_AUTO_ON;
+ } else {
+ s->mttcg_enabled = ON_OFF_AUTO_OFF;
+ }
+ }
+ if (s->mttcg_enabled == ON_OFF_AUTO_ON) {
+ max_threads = ms->smp.max_cpus;
+ }
+#endif
+
tcg_allowed = true;
page_init();
tb_htable_init();
-
-#ifndef CONFIG_USER_ONLY
- if (s->mttcg_enabled) {
- max_threads = ms->smp.max_cpus;
- }
-#endif
tcg_init(s->tb_size * MiB, s->splitwx_enabled, max_threads);
#if defined(CONFIG_SOFTMMU)
@@ -144,7 +142,7 @@ static char *tcg_get_thread(Object *obj, Error **errp)
{
TCGState *s = TCG_STATE(obj);
- return g_strdup(s->mttcg_enabled ? "multi" : "single");
+ return g_strdup(s->mttcg_enabled == ON_OFF_AUTO_ON ? "multi" : "single");
}
static void tcg_set_thread(Object *obj, const char *value, Error **errp)
@@ -159,10 +157,10 @@ static void tcg_set_thread(Object *obj, const char
*value, Error **errp)
warn_report("Guest not yet converted to MTTCG - "
"you may get unexpected results");
#endif
- s->mttcg_enabled = true;
+ s->mttcg_enabled = ON_OFF_AUTO_ON;
}
} else if (strcmp(value, "single") == 0) {
- s->mttcg_enabled = false;
+ s->mttcg_enabled = ON_OFF_AUTO_OFF;
} else {
error_setg(errp, "Invalid 'thread' setting %s", value);
}
--
2.43.0
