From 56d00aa7945e01291b40d05c60dde4b4dab0ce4c Mon Sep 17 00:00:00 2001 From: Keir Fraser Date: Fri, 26 Mar 2010 08:49:13 +0000 Subject: [PATCH] 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 --- xen/drivers/cpufreq/utility.c | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) diff --git a/xen/drivers/cpufreq/utility.c b/xen/drivers/cpufreq/utility.c index 2d9921dcc5..c730df951f 100644 --- a/xen/drivers/cpufreq/utility.c +++ b/xen/drivers/cpufreq/utility.c @@ -63,13 +63,14 @@ void cpufreq_residency_update(unsigned int cpu, uint8_t state) 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 @@ void cpufreq_statistic_update(unsigned int cpu, uint8_t from, uint8_t to) 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 cpuid) 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 cpuid) 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_exit(unsigned int cpuid) 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; -- 2.30.2