@@ -23,6 +23,7 @@
#include <asm/types.h>
#include <asm/mmu.h>
#include <asm/firmware.h>
+#include <asm/paca.h>
/*
* The lppaca is the "virtual processor area" registered with the hypervisor,
@@ -105,14 +106,20 @@ struct lppaca {
*/
#define LPPACA_OLD_SHARED_PROC 2
-static inline bool lppaca_shared_proc(struct lppaca *l)
+#ifdef CONFIG_PPC_PSERIES
+/*
+ * All CPUs should have the same shared proc value, so directly access the PACA
+ * to avoid false positives from DEBUG_PREEMPT.
+ */
+static inline bool lppaca_shared_proc(void)
{
+ struct lppaca *l = local_paca->lppaca_ptr;
+
if (!firmware_has_feature(FW_FEATURE_SPLPAR))
return false;
return !!(l->__old_status & LPPACA_OLD_SHARED_PROC);
}
-#ifdef CONFIG_PPC_PSERIES
#define get_lppaca() (get_paca()->lppaca_ptr)
#endif
@@ -640,16 +640,8 @@ static const struct proc_ops vcpudispatch_stats_freq_proc_ops = {
static int __init vcpudispatch_stats_procfs_init(void)
{
- /*
- * Avoid smp_processor_id while preemptible. All CPUs should have
- * the same value for lppaca_shared_proc.
- */
- preempt_disable();
- if (!lppaca_shared_proc(get_lppaca())) {
- preempt_enable();
+ if (!lppaca_shared_proc())
return 0;
- }
- preempt_enable();
if (!proc_create("powerpc/vcpudispatch_stats", 0600, NULL,
&vcpudispatch_stats_proc_ops))
@@ -206,7 +206,7 @@ static void parse_ppp_data(struct seq_file *m)
ppp_data.active_system_procs);
/* pool related entries are appropriate for shared configs */
- if (lppaca_shared_proc(get_lppaca())) {
+ if (lppaca_shared_proc()) {
unsigned long pool_idle_time, pool_procs;
seq_printf(m, "pool=%d\n", ppp_data.pool_num);
@@ -560,7 +560,7 @@ static int pseries_lparcfg_data(struct seq_file *m, void *v)
partition_potential_processors);
seq_printf(m, "shared_processor_mode=%d\n",
- lppaca_shared_proc(get_lppaca()));
+ lppaca_shared_proc());
#ifdef CONFIG_PPC_64S_HASH_MMU
if (!radix_enabled())
@@ -849,7 +849,7 @@ static void __init pSeries_setup_arch(void)
if (firmware_has_feature(FW_FEATURE_LPAR)) {
vpa_init(boot_cpuid);
- if (lppaca_shared_proc(get_lppaca())) {
+ if (lppaca_shared_proc()) {
static_branch_enable(&shared_processor);
pv_spinlocks_init();
#ifdef CONFIG_PARAVIRT_TIME_ACCOUNTING
@@ -414,13 +414,7 @@ static int __init pseries_idle_probe(void)
return -ENODEV;
if (firmware_has_feature(FW_FEATURE_SPLPAR)) {
- /*
- * Use local_paca instead of get_lppaca() since
- * preemption is not disabled, and it is not required in
- * fact, since lppaca_ptr does not need to be the value
- * associated to the current CPU, it can be from any CPU.
- */
- if (lppaca_shared_proc(local_paca->lppaca_ptr)) {
+ if (lppaca_shared_proc()) {
cpuidle_state_table = shared_states;
max_idle_state = ARRAY_SIZE(shared_states);
} else {