Laurent Vivier <laur...@vivier.eu> writes: > Le 24/02/2017 à 12:20, Alex Bennée a écrit : >> There are a couple of changes that occur at the same time here: >> >> - introduce a single vCPU qemu_tcg_cpu_thread_fn >> >> One of these is spawned per vCPU with its own Thread and Condition >> variables. qemu_tcg_rr_cpu_thread_fn is the new name for the old >> single threaded function. >> >> - the TLS current_cpu variable is now live for the lifetime of MTTCG >> vCPU threads. This is for future work where async jobs need to know >> the vCPU context they are operating in. >> >> The user to switch on multi-thread behaviour and spawn a thread >> per-vCPU. For a simple test kvm-unit-test like: >> >> ./arm/run ./arm/locking-test.flat -smp 4 -accel tcg,thread=multi >> >> Will now use 4 vCPU threads and have an expected FAIL (instead of the >> unexpected PASS) as the default mode of the test has no protection when >> incrementing a shared variable. >> >> We enable the parallel_cpus flag to ensure we generate correct barrier >> and atomic code if supported by the front and backends. This doesn't >> automatically enable MTTCG until default_mttcg_enabled() is updated to >> check the configuration is supported. > > This commit breaks linux-user mode: > > debian-8 with qemu-ppc on x86_64 with ltp-full-20170116 > > cd /opt/ltp > ./runltp -p -l "qemu-$(date +%FT%T).log" -f /opt/ltp/runtest/syscalls -s > setgroups03 > > setgroups03 1 TPASS : setgroups(65537) fails, Size is > > sysconf(_SC_NGROUPS_MAX), errno=22 > qemu-ppc: /home/laurent/Projects/qemu/include/qemu/rcu.h:89: > rcu_read_unlock: Assertion `p_rcu_reader->depth != 0' failed. > qemu-ppc: /home/laurent/Projects/qemu/include/qemu/rcu.h:89: > rcu_read_unlock: Assertion `p_rcu_reader->depth != 0' failed. > qemu-ppc: /home/laurent/Projects/qemu/include/qemu/rcu.h:89: > rcu_read_unlock: Assertion `p_rcu_reader->depth != 0' failed. > ...
Interesting. I can only think the current_cpu change has broken it because most of the changes in this commit affect softmmu targets only (linux-user has its own run loop). Thanks for the report - I'll look into it. -- Alex Bennée
