summaryrefslogtreecommitdiff
path: root/accel
diff options
context:
space:
mode:
authorPavel Dovgalyuk <pavel.dovgalyuk@ispras.ru>2020-12-08 12:10:58 +0300
committerPaolo Bonzini <pbonzini@redhat.com>2020-12-15 12:52:04 -0500
commit835cbd8d44b62217b8774b39e1bfd314750c2c51 (patch)
treedc14acd026d3904b096b646895566d2964dc229d /accel
parent90d6a086bb220bcd8b2ba3c881ac53862caa4987 (diff)
downloadqemu-835cbd8d44b62217b8774b39e1bfd314750c2c51.zip
icount: improve exec nocache usage
cpu-exec tries to execute TB without caching when current icount budget is over. But sometimes refilled budget is big enough to try executing cached blocks. This patch checks that instruction budget is big enough for next block execution instead of just running cpu_exec_nocache. It halves the number of calls of cpu_exec_nocache function during tested OS boot scenario. Signed-off-by: Pavel Dovgalyuk <pavel.dovgalyuk@ispras.ru> Message-Id: <160741865825.348476.7169239332367828943.stgit@pasha-ThinkPad-X280> Reviewed-by: Richard Henderson <richard.henderson@linaro.org> Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'accel')
-rw-r--r--accel/tcg/cpu-exec.c2
1 files changed, 1 insertions, 1 deletions
diff --git a/accel/tcg/cpu-exec.c b/accel/tcg/cpu-exec.c
index 58aea605d8..251b340fb9 100644
--- a/accel/tcg/cpu-exec.c
+++ b/accel/tcg/cpu-exec.c
@@ -685,7 +685,7 @@ static inline void cpu_loop_exec_tb(CPUState *cpu, TranslationBlock *tb,
insns_left = MIN(0xffff, cpu->icount_budget);
cpu_neg(cpu)->icount_decr.u16.low = insns_left;
cpu->icount_extra = cpu->icount_budget - insns_left;
- if (!cpu->icount_extra) {
+ if (!cpu->icount_extra && insns_left < tb->icount) {
/* Execute any remaining instructions, then let the main loop
* handle the next event.
*/