diff options
| author | Paolo Bonzini <pbonzini@redhat.com> | 2013-09-10 12:58:35 +0200 |
|---|---|---|
| committer | Christoffer Dall <christoffer.dall@linaro.org> | 2014-10-02 17:18:06 +0200 |
| commit | 753f251708b5322430cf4902264d432a5daf06e4 (patch) | |
| tree | 2f041eddb0a034fd18283b1f6a71085c2bc7f5ee /virt/kvm/kvm_main.c | |
| parent | ae0e4b34f8d96028faefddb83994cfd2c8cb8681 (diff) | |
KVM: protect kvm_usage_count with its own spinlock
The VM list need not be protected by a raw spinlock. Separate the
two so that kvm_lock can be made non-raw.
Cc: kvm@vger.kernel.org
Cc: gleb@redhat.com
Cc: jan.kiszka@siemens.com
Reviewed-by: Gleb Natapov <gleb@redhat.com>
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
(cherry picked from commit 4a937f96f3a29c58b7edd349d2e4dfac371efdf2)
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>
Diffstat (limited to 'virt/kvm/kvm_main.c')
| -rw-r--r-- | virt/kvm/kvm_main.c | 19 |
1 files changed, 10 insertions, 9 deletions
diff --git a/virt/kvm/kvm_main.c b/virt/kvm/kvm_main.c index 7103b989ba54..6bc0481bf8e5 100644 --- a/virt/kvm/kvm_main.c +++ b/virt/kvm/kvm_main.c @@ -71,6 +71,7 @@ MODULE_LICENSE("GPL"); */ DEFINE_RAW_SPINLOCK(kvm_lock); +static DEFINE_RAW_SPINLOCK(kvm_count_lock); LIST_HEAD(vm_list); static cpumask_var_t cpus_hardware_enabled; @@ -2683,10 +2684,10 @@ static void hardware_enable_nolock(void *junk) static void hardware_enable(void) { - raw_spin_lock(&kvm_lock); + raw_spin_lock(&kvm_count_lock); if (kvm_usage_count) hardware_enable_nolock(NULL); - raw_spin_unlock(&kvm_lock); + raw_spin_unlock(&kvm_count_lock); } static void hardware_disable_nolock(void *junk) @@ -2701,10 +2702,10 @@ static void hardware_disable_nolock(void *junk) static void hardware_disable(void) { - raw_spin_lock(&kvm_lock); + raw_spin_lock(&kvm_count_lock); if (kvm_usage_count) hardware_disable_nolock(NULL); - raw_spin_unlock(&kvm_lock); + raw_spin_unlock(&kvm_count_lock); } static void hardware_disable_all_nolock(void) @@ -2718,16 +2719,16 @@ static void hardware_disable_all_nolock(void) static void hardware_disable_all(void) { - raw_spin_lock(&kvm_lock); + raw_spin_lock(&kvm_count_lock); hardware_disable_all_nolock(); - raw_spin_unlock(&kvm_lock); + raw_spin_unlock(&kvm_count_lock); } static int hardware_enable_all(void) { int r = 0; - raw_spin_lock(&kvm_lock); + raw_spin_lock(&kvm_count_lock); kvm_usage_count++; if (kvm_usage_count == 1) { @@ -2740,7 +2741,7 @@ static int hardware_enable_all(void) } } - raw_spin_unlock(&kvm_lock); + raw_spin_unlock(&kvm_count_lock); return r; } @@ -3050,7 +3051,7 @@ static int kvm_suspend(void) static void kvm_resume(void) { if (kvm_usage_count) { - WARN_ON(raw_spin_is_locked(&kvm_lock)); + WARN_ON(raw_spin_is_locked(&kvm_count_lock)); hardware_enable_nolock(NULL); } } |