diff options
| author | Liu Ping Fan <qemulist@gmail.com> | 2013-09-25 14:20:58 +0800 |
|---|---|---|
| committer | Paolo Bonzini <pbonzini@redhat.com> | 2013-10-17 17:30:52 +0200 |
| commit | cb365646a942ed58aae053064b2048a415337ba2 (patch) | |
| tree | 1c032ed0e7f61274484dcd13b7d73684649d3331 /include | |
| parent | ea753d81e8b085d679f13e4a6023e003e9854d51 (diff) | |
timer: protect timers_state's clock with seqlock
QEMU_CLOCK_VIRTUAL may be read outside BQL. This will make its
foundation, i.e. cpu_clock_offset exposed to race condition.
Using private lock to protect it.
After this patch, reading QEMU_CLOCK_VIRTUAL is thread safe
unless use_icount is true, in which case the existing callers
still rely on the BQL.
Lock rule: private lock innermost, ie BQL->"this lock"
Signed-off-by: Liu Ping Fan <pingfank@linux.vnet.ibm.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/qemu/timer.h | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/include/qemu/timer.h b/include/qemu/timer.h index b58903bef5..016e29ae95 100644 --- a/include/qemu/timer.h +++ b/include/qemu/timer.h @@ -653,7 +653,9 @@ static inline int64_t qemu_soonest_timeout(int64_t timeout1, int64_t timeout2) void init_clocks(void); int64_t cpu_get_ticks(void); +/* Caller must hold BQL */ void cpu_enable_ticks(void); +/* Caller must hold BQL */ void cpu_disable_ticks(void); static inline int64_t get_ticks_per_sec(void) |