cpufreq: fix statistic lock problem
cpufreq_statistic_lock should not only protect the statistic memory pointed by
cpufreq_statistic_data[cpu], but also have to protect the pointer in
cpufreq_statistic_data[cpu] itself. So move the read operation of
cpufreq_statistic_data[cpu] after spin_lock(cpufreq_statistic_lock).
Signed-off-by: Wei Gang <gang.wei@intel.com>
diff -r f7aeab5b7796 xen/drivers/cpufreq/utility.c
--- a/xen/drivers/cpufreq/utility.c Wed Mar 24 17:05:16 2010 +0800
+++ b/xen/drivers/cpufreq/utility.c Thu Mar 25 16:58:44 2010 +0800
@@ -63,13 +63,14 @@ void cpufreq_residency_update(unsigned i
void cpufreq_statistic_update(unsigned int cpu, uint8_t from, uint8_t to)
{
- struct pm_px *pxpt = cpufreq_statistic_data[cpu];
+ struct pm_px *pxpt;
struct processor_pminfo *pmpt = processor_pminfo[cpu];
spinlock_t *cpufreq_statistic_lock =
&per_cpu(cpufreq_statistic_lock, cpu);
spin_lock(cpufreq_statistic_lock);
+ pxpt = cpufreq_statistic_data[cpu];
if ( !pxpt || !pmpt ) {
spin_unlock(cpufreq_statistic_lock);
return;
@@ -89,7 +90,7 @@ int cpufreq_statistic_init(unsigned int
int cpufreq_statistic_init(unsigned int cpuid)
{
uint32_t i, count;
- struct pm_px *pxpt = cpufreq_statistic_data[cpuid];
+ struct pm_px *pxpt;
const struct processor_pminfo *pmpt = processor_pminfo[cpuid];
spinlock_t *cpufreq_statistic_lock =
&per_cpu(cpufreq_statistic_lock, cpuid);
@@ -99,6 +100,7 @@ int cpufreq_statistic_init(unsigned int
spin_lock(cpufreq_statistic_lock);
+ pxpt = cpufreq_statistic_data[cpuid];
if ( pxpt ) {
spin_unlock(cpufreq_statistic_lock);
return 0;
@@ -148,12 +150,13 @@ int cpufreq_statistic_init(unsigned int
void cpufreq_statistic_exit(unsigned int cpuid)
{
- struct pm_px *pxpt = cpufreq_statistic_data[cpuid];
+ struct pm_px *pxpt;
spinlock_t *cpufreq_statistic_lock =
&per_cpu(cpufreq_statistic_lock, cpuid);
spin_lock(cpufreq_statistic_lock);
+ pxpt = cpufreq_statistic_data[cpuid];
if (!pxpt) {
spin_unlock(cpufreq_statistic_lock);
return;
@@ -170,13 +173,14 @@ void cpufreq_statistic_reset(unsigned in
void cpufreq_statistic_reset(unsigned int cpuid)
{
uint32_t i, j, count;
- struct pm_px *pxpt = cpufreq_statistic_data[cpuid];
+ struct pm_px *pxpt;
const struct processor_pminfo *pmpt = processor_pminfo[cpuid];
spinlock_t *cpufreq_statistic_lock =
&per_cpu(cpufreq_statistic_lock, cpuid);
spin_lock(cpufreq_statistic_lock);
+ pxpt = cpufreq_statistic_data[cpuid];
if ( !pmpt || !pxpt || !pxpt->u.pt || !pxpt->u.trans_pt ) {
spin_unlock(cpufreq_statistic_lock);
return;
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