Pierrick Bouvier <pierrick.bouv...@linaro.org> writes: > The goal here is to be able to scale temporally execution of qemu-user/system, > using a given number of instructions per second. > > We define a virtual clock, that can be late or in advance compared to real > time. > When we are in advance, we slow execution (by sleeping) until catching real > time. > > Finally, we should be able to cleanup icount=auto mode completely, and keep > icount usage for determistic purposes only. > > It is built upon new TCG Plugins inline ops (store + conditional callbacks), > now > merged on master. > > Example in user-mode: > > - Retrieve number of instructions to execute /bin/true > $ ./build/qemu-x86_64 -plugin ./build/tests/plugin/libinsn.so -d plugin > /bin/true > cpu 0 insns: 120546 > total insns: 120546 > - Slow execution to match 5 seconds > $ time ./build/qemu-x86_64 -plugin > ./build/contrib/plugins/libips,ips=$((120546/5)) /bin/true > real 0m4.985s > > Tested in system mode by booting a full debian system, and using: > $ sysbench cpu run > Performance decrease linearly with the given number of ips.
Queued to plugins/next, thanks. -- Alex Bennée Virtualisation Tech Lead @ Linaro
