Lock contention in the hot path of moving between existing patched
TranslationBlocks is the main drag in multithreaded performance. This
patch pushes the tb_lock() usage down to the two places that really need
it:
- code generation (tb_gen_code)
- jump patching (tb_add_jump)
The rest of the code doesn't really need to hold a lock as it is either
using per-CPU structures, atomically updated or designed to be used in
concurrent read situations (qht_lookup).
To keep things simple I removed the #ifdef CONFIG_USER_ONLY stuff as the
locks become NOPs anyway until the MTTCG work is completed.
Signed-off-by: Alex Bennée <address@hidden>
---
v3
- fix merge conflicts with Sergey's patch
v4
- revert name tweaking
- drop test jmp_list_next outside lock
- mention lock NOPs in comments
---
cpu-exec.c | 49 ++++++++++++++++++++++---------------------------
1 file changed, 22 insertions(+), 27 deletions(-)