/* Take the mutex lock for this node and then decrement the reference count */
mutex_lock(&ref->lock);
+ if (ref->refc == 0) {
+ /*
+ * The scenario where this is true is, when perf session is
+ * started, followed by offlining of all cpus in a given node.
+ *
+ * In the cpuhotplug offline path, ppc_nest_imc_cpu_offline()
+ * function set the ref->count to zero, if the cpu which is
+ * about to offline is the last cpu in a given node and make
+ * an OPAL call to disable the engine in that node.
+ *
+ */
+ mutex_unlock(&ref->lock);
+ return;
+ }
ref->refc--;
if (ref->refc == 0) {
rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_NEST,
/* We need only vbase for core counters */
mem_info->vbase = page_address(alloc_pages_node(phys_id,
- GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE,
- get_order(size)));
+ GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
+ __GFP_NOWARN, get_order(size)));
if (!mem_info->vbase)
return -ENOMEM;
if (!cpumask_test_and_clear_cpu(cpu, &core_imc_cpumask))
return 0;
+ /*
+ * Check whether core_imc is registered. We could end up here
+ * if the cpuhotplug callback registration fails. i.e, callback
+ * invokes the offline path for all sucessfully registered cpus.
+ * At this stage, core_imc pmu will not be registered and we
+ * should return here.
+ *
+ * We return with a zero since this is not an offline failure.
+ * And cpuhp_setup_state() returns the actual failure reason
+ * to the caller, which inturn will call the cleanup routine.
+ */
+ if (!core_imc_pmu->pmu.event_init)
+ return 0;
+
/* Find any online cpu in that core except the current "cpu" */
ncpu = cpumask_any_but(cpu_sibling_mask(cpu), cpu);
return;
mutex_lock(&ref->lock);
+ if (ref->refc == 0) {
+ /*
+ * The scenario where this is true is, when perf session is
+ * started, followed by offlining of all cpus in a given core.
+ *
+ * In the cpuhotplug offline path, ppc_core_imc_cpu_offline()
+ * function set the ref->count to zero, if the cpu which is
+ * about to offline is the last cpu in a given core and make
+ * an OPAL call to disable the engine in that core.
+ *
+ */
+ mutex_unlock(&ref->lock);
+ return;
+ }
ref->refc--;
if (ref->refc == 0) {
rc = opal_imc_counters_stop(OPAL_IMC_COUNTERS_CORE,
* free the memory in cpu offline path.
*/
local_mem = page_address(alloc_pages_node(phys_id,
- GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE,
- get_order(size)));
+ GFP_KERNEL | __GFP_ZERO | __GFP_THISNODE |
+ __GFP_NOWARN, get_order(size)));
if (!local_mem)
return -ENOMEM;
static void cleanup_all_core_imc_memory(void)
{
- int i, nr_cores = num_present_cpus() / threads_per_core;
+ int i, nr_cores = DIV_ROUND_UP(num_present_cpus(), threads_per_core);
struct imc_mem_info *ptr = core_imc_pmu->mem_info;
int size = core_imc_pmu->counter_mem_size;
}
/* Only free the attr_groups which are dynamically allocated */
- kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs);
+ if (pmu_ptr->attr_groups[IMC_EVENT_ATTR])
+ kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]->attrs);
kfree(pmu_ptr->attr_groups[IMC_EVENT_ATTR]);
kfree(pmu_ptr);
return;
if (!pmu_ptr->pmu.name)
return -ENOMEM;
- nr_cores = num_present_cpus() / threads_per_core;
+ nr_cores = DIV_ROUND_UP(num_present_cpus(), threads_per_core);
pmu_ptr->mem_info = kcalloc(nr_cores, sizeof(struct imc_mem_info),
GFP_KERNEL);