72db6d54a4
This plugin uses the new time control interface to make decisions about the state of time during the emulation. The algorithm is currently very simple. The user specifies an ips rate which applies per core. If the core runs ahead of its allocated execution time the plugin sleeps for a bit to let real time catch up. Either way time is updated for the emulation as a function of total executed instructions with some adjustments for cores that idle. Examples -------- Slow down execution of /bin/true: $ num_insn=$(./build/qemu-x86_64 -plugin ./build/tests/plugin/libinsn.so -d plugin /bin/true |& grep total | sed -e 's/.*: //') $ time ./build/qemu-x86_64 -plugin ./build/contrib/plugins/libips.so,ips=$(($num_insn/4)) /bin/true real 4.000s Boot a Linux kernel simulating a 250MHz cpu: $ /build/qemu-system-x86_64 -kernel /boot/vmlinuz-6.1.0-21-amd64 -append "console=ttyS0" -plugin ./build/contrib/plugins/libips.so,ips=$((250*1000*1000)) -smp 1 -m 512 check time until kernel panic on serial0 Tested in system mode by booting a full debian system, and using: $ sysbench cpu run Performance decrease linearly with the given number of ips. Signed-off-by: Pierrick Bouvier <pierrick.bouvier@linaro.org> Message-Id: <20240530220610.1245424-7-pierrick.bouvier@linaro.org> Signed-off-by: Alex Bennée <alex.bennee@linaro.org> Message-Id: <20240620152220.2192768-11-alex.bennee@linaro.org> |
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.. | ||
cache.c | ||
drcov.c | ||
execlog.c | ||
hotblocks.c | ||
hotpages.c | ||
howvec.c | ||
hwprofile.c | ||
ips.c | ||
lockstep.c | ||
Makefile | ||
win32_linker.c |