[29/31] kvm: Do not use qemu_fair_mutex

Message ID b66042c722e4e7b2811a08873b1ecf2c2c1e5f0a.1295859760.git.mtosatti@redhat.com
State New
Headers show

Commit Message

Marcelo Tosatti Jan. 24, 2011, 9:02 a.m.
From: Jan Kiszka <jan.kiszka@siemens.com>

The imbalance in the hold time of qemu_global_mutex only exists in TCG
mode. In contrast to TCG VCPUs, KVM drops the global lock during guest
execution. We already avoid touching the fairness lock from the
IO-thread in KVM mode, so also stop using it from the VCPU threads.

Signed-off-by: Jan Kiszka <jan.kiszka@siemens.com>
Signed-off-by: Marcelo Tosatti <mtosatti@redhat.com>
 cpus.c |    2 --
 1 files changed, 0 insertions(+), 2 deletions(-)


diff --git a/cpus.c b/cpus.c
index 0309189..4c9928e 100644
--- a/cpus.c
+++ b/cpus.c
@@ -735,9 +735,7 @@  static sigset_t block_io_signals(void)
 void qemu_mutex_lock_iothread(void)
     if (kvm_enabled()) {
-        qemu_mutex_lock(&qemu_fair_mutex);
-        qemu_mutex_unlock(&qemu_fair_mutex);
     } else {
         if (qemu_mutex_trylock(&qemu_global_mutex)) {