On 20/07/2015 19:36, Alex Bennée wrote:
fred.kon...@greensocs.com writes:
From: KONRAD Frederic <fred.kon...@greensocs.com>
This is the async_safe_work introduction bit of the Multithread TCG work.
Rebased on current upstream (6169b60285fe1ff730d840a49527e721bfb30899).
(Currently untested as I need to rebase MTTCG first.)
It can be cloned here:
http://git.greensocs.com/fkonrad/mttcg.git branch async_work_v3
The first patch introduces a mutex to protect the existing queued_work_*
CPUState members against multiple (concurent) access.
The second patch introduces a tcg_exec_flag which will be 1 when we are inside
cpu_exec(), -1 when we must not enter the cpu execution and 0 when we are
allowed to do so. This is required as safe work need to be sure that's all vCPU
are outside cpu_exec().
The last patch introduces async_safe_work. It allows to add some work which will
be done asynchronously but only when all vCPUs are outside cpu_exec(). The tcg
thread will wait that no vCPUs have any pending safe work before reentering
cpu-exec().
Changes V2 -> V3:
* Check atomically we are not in the executiong loop to fix the race
condition
which might happen.
Changes V1 -> V2:
* Release the lock while running the callback for both async and safe work.
KONRAD Frederic (3):
cpus: protect queued_work_* with work_mutex.
cpus: add tcg_exec_flag.
cpus: introduce async_run_safe_work_on_cpu.
Also currently breaks a lot of targets:
https://travis-ci.org/stsquad/qemu/builds/71797143
oops yes, seems linux-user is not happy at all.
Will fix that.
Thanks,
Fred
cpu-exec.c | 10 ++++
cpus.c | 160 ++++++++++++++++++++++++++++++++++++++++--------------
include/qom/cpu.h | 57 +++++++++++++++++++
qom/cpu.c | 20 +++++++
4 files changed, 207 insertions(+), 40 deletions(-)
