#include <linux/smp.h>
#include <linux/hw_breakpoint.h>
-
-
/*
* Constraints data
*/
+struct bp_cpuinfo {
+ /* Number of pinned cpu breakpoints in a cpu */
+ unsigned int cpu_pinned;
+ /* tsk_pinned[n] is the number of tasks having n+1 breakpoints */
+ unsigned int *tsk_pinned;
+ /* Number of non-pinned cpu/task breakpoints in a cpu */
+ unsigned int flexible; /* XXX: placeholder, see fetch_this_slot() */
+};
-/* Number of pinned cpu breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_cpu_bp_pinned[TYPE_MAX]);
-
-/* Number of pinned task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int *, nr_task_bp_pinned[TYPE_MAX]);
-
-/* Number of non-pinned cpu/task breakpoints in a cpu */
-static DEFINE_PER_CPU(unsigned int, nr_bp_flexible[TYPE_MAX]);
-
+static DEFINE_PER_CPU(struct bp_cpuinfo, bp_cpuinfo[TYPE_MAX]);
static int nr_slots[TYPE_MAX];
+static struct bp_cpuinfo *get_bp_info(int cpu, enum bp_type_idx type)
+{
+ return per_cpu_ptr(bp_cpuinfo + type, cpu);
+}
+
/* Keep track of the breakpoints attached to tasks */
static LIST_HEAD(bp_task_head);
*/
static unsigned int max_task_bp_pinned(int cpu, enum bp_type_idx type)
{
+ unsigned int *tsk_pinned = get_bp_info(cpu, type)->tsk_pinned;
int i;
- unsigned int *tsk_pinned = per_cpu(nr_task_bp_pinned[type], cpu);
for (i = nr_slots[type] - 1; i >= 0; i--) {
if (tsk_pinned[i] > 0)
return count;
}
+static const struct cpumask *cpumask_of_bp(struct perf_event *bp)
+{
+ if (bp->cpu >= 0)
+ return cpumask_of(bp->cpu);
+ return cpu_possible_mask;
+}
+
/*
* Report the number of pinned/un-pinned breakpoints we have in
* a given cpu (cpu > -1) or in all of them (cpu = -1).
fetch_bp_busy_slots(struct bp_busy_slots *slots, struct perf_event *bp,
enum bp_type_idx type)
{
- int cpu = bp->cpu;
- struct task_struct *tsk = bp->hw.bp_target;
-
- if (cpu >= 0) {
- slots->pinned = per_cpu(nr_cpu_bp_pinned[type], cpu);
- if (!tsk)
- slots->pinned += max_task_bp_pinned(cpu, type);
- else
- slots->pinned += task_bp_pinned(cpu, bp, type);
- slots->flexible = per_cpu(nr_bp_flexible[type], cpu);
-
- return;
- }
+ const struct cpumask *cpumask = cpumask_of_bp(bp);
+ int cpu;
- for_each_possible_cpu(cpu) {
- unsigned int nr;
+ for_each_cpu(cpu, cpumask) {
+ struct bp_cpuinfo *info = get_bp_info(cpu, type);
+ int nr;
- nr = per_cpu(nr_cpu_bp_pinned[type], cpu);
- if (!tsk)
+ nr = info->cpu_pinned;
+ if (!bp->hw.bp_target)
nr += max_task_bp_pinned(cpu, type);
else
nr += task_bp_pinned(cpu, bp, type);
if (nr > slots->pinned)
slots->pinned = nr;
- nr = per_cpu(nr_bp_flexible[type], cpu);
-
+ nr = info->flexible;
if (nr > slots->flexible)
slots->flexible = nr;
}
/*
* Add a pinned breakpoint for the given task in our constraint table
*/
-static void toggle_bp_task_slot(struct perf_event *bp, int cpu, bool enable,
+static void toggle_bp_task_slot(struct perf_event *bp, int cpu,
enum bp_type_idx type, int weight)
{
- unsigned int *tsk_pinned;
- int old_count = 0;
- int old_idx = 0;
- int idx = 0;
-
- old_count = task_bp_pinned(cpu, bp, type);
- old_idx = old_count - 1;
- idx = old_idx + weight;
-
- /* tsk_pinned[n] is the number of tasks having n breakpoints */
- tsk_pinned = per_cpu(nr_task_bp_pinned[type], cpu);
- if (enable) {
- tsk_pinned[idx]++;
- if (old_count > 0)
- tsk_pinned[old_idx]--;
- } else {
- tsk_pinned[idx]--;
- if (old_count > 0)
- tsk_pinned[old_idx]++;
- }
+ unsigned int *tsk_pinned = get_bp_info(cpu, type)->tsk_pinned;
+ int old_idx, new_idx;
+
+ old_idx = task_bp_pinned(cpu, bp, type) - 1;
+ new_idx = old_idx + weight;
+
+ if (old_idx >= 0)
+ tsk_pinned[old_idx]--;
+ if (new_idx >= 0)
+ tsk_pinned[new_idx]++;
}
/*
toggle_bp_slot(struct perf_event *bp, bool enable, enum bp_type_idx type,
int weight)
{
- int cpu = bp->cpu;
- struct task_struct *tsk = bp->hw.bp_target;
+ const struct cpumask *cpumask = cpumask_of_bp(bp);
+ int cpu;
- /* Pinned counter cpu profiling */
- if (!tsk) {
+ if (!enable)
+ weight = -weight;
- if (enable)
- per_cpu(nr_cpu_bp_pinned[type], bp->cpu) += weight;
- else
- per_cpu(nr_cpu_bp_pinned[type], bp->cpu) -= weight;
+ /* Pinned counter cpu profiling */
+ if (!bp->hw.bp_target) {
+ get_bp_info(bp->cpu, type)->cpu_pinned += weight;
return;
}
/* Pinned counter task profiling */
-
- if (!enable)
- list_del(&bp->hw.bp_list);
-
- if (cpu >= 0) {
- toggle_bp_task_slot(bp, cpu, enable, type, weight);
- } else {
- for_each_possible_cpu(cpu)
- toggle_bp_task_slot(bp, cpu, enable, type, weight);
- }
+ for_each_cpu(cpu, cpumask)
+ toggle_bp_task_slot(bp, cpu, type, weight);
if (enable)
list_add_tail(&bp->hw.bp_list, &bp_task_head);
+ else
+ list_del(&bp->hw.bp_list);
}
/*
*
* - If attached to a single cpu, check:
*
- * (per_cpu(nr_bp_flexible, cpu) || (per_cpu(nr_cpu_bp_pinned, cpu)
- * + max(per_cpu(nr_task_bp_pinned, cpu)))) < HBP_NUM
+ * (per_cpu(info->flexible, cpu) || (per_cpu(info->cpu_pinned, cpu)
+ * + max(per_cpu(info->tsk_pinned, cpu)))) < HBP_NUM
*
* -> If there are already non-pinned counters in this cpu, it means
* there is already a free slot for them.
*
* - If attached to every cpus, check:
*
- * (per_cpu(nr_bp_flexible, *) || (max(per_cpu(nr_cpu_bp_pinned, *))
- * + max(per_cpu(nr_task_bp_pinned, *)))) < HBP_NUM
+ * (per_cpu(info->flexible, *) || (max(per_cpu(info->cpu_pinned, *))
+ * + max(per_cpu(info->tsk_pinned, *)))) < HBP_NUM
*
* -> This is roughly the same, except we check the number of per cpu
* bp for every cpu and we keep the max one. Same for the per tasks
*
* - If attached to a single cpu, check:
*
- * ((per_cpu(nr_bp_flexible, cpu) > 1) + per_cpu(nr_cpu_bp_pinned, cpu)
- * + max(per_cpu(nr_task_bp_pinned, cpu))) < HBP_NUM
+ * ((per_cpu(info->flexible, cpu) > 1) + per_cpu(info->cpu_pinned, cpu)
+ * + max(per_cpu(info->tsk_pinned, cpu))) < HBP_NUM
*
- * -> Same checks as before. But now the nr_bp_flexible, if any, must keep
+ * -> Same checks as before. But now the info->flexible, if any, must keep
* one register at least (or they will never be fed).
*
* - If attached to every cpus, check:
*
- * ((per_cpu(nr_bp_flexible, *) > 1) + max(per_cpu(nr_cpu_bp_pinned, *))
- * + max(per_cpu(nr_task_bp_pinned, *))) < HBP_NUM
+ * ((per_cpu(info->flexible, *) > 1) + max(per_cpu(info->cpu_pinned, *))
+ * + max(per_cpu(info->tsk_pinned, *))) < HBP_NUM
*/
static int __reserve_bp_slot(struct perf_event *bp)
{
perf_overflow_handler_t triggered,
void *context)
{
- struct perf_event * __percpu *cpu_events, **pevent, *bp;
- long err;
+ struct perf_event * __percpu *cpu_events, *bp;
+ long err = 0;
int cpu;
cpu_events = alloc_percpu(typeof(*cpu_events));
get_online_cpus();
for_each_online_cpu(cpu) {
- pevent = per_cpu_ptr(cpu_events, cpu);
bp = perf_event_create_kernel_counter(attr, cpu, NULL,
triggered, context);
-
- *pevent = bp;
-
if (IS_ERR(bp)) {
err = PTR_ERR(bp);
- goto fail;
+ break;
}
- }
- put_online_cpus();
- return cpu_events;
-
-fail:
- for_each_online_cpu(cpu) {
- pevent = per_cpu_ptr(cpu_events, cpu);
- if (IS_ERR(*pevent))
- break;
- unregister_hw_breakpoint(*pevent);
+ per_cpu(*cpu_events, cpu) = bp;
}
put_online_cpus();
- free_percpu(cpu_events);
+ if (likely(!err))
+ return cpu_events;
+
+ unregister_wide_hw_breakpoint(cpu_events);
return (void __percpu __force *)ERR_PTR(err);
}
EXPORT_SYMBOL_GPL(register_wide_hw_breakpoint);
void unregister_wide_hw_breakpoint(struct perf_event * __percpu *cpu_events)
{
int cpu;
- struct perf_event **pevent;
- for_each_possible_cpu(cpu) {
- pevent = per_cpu_ptr(cpu_events, cpu);
- unregister_hw_breakpoint(*pevent);
- }
+ for_each_possible_cpu(cpu)
+ unregister_hw_breakpoint(per_cpu(*cpu_events, cpu));
+
free_percpu(cpu_events);
}
EXPORT_SYMBOL_GPL(unregister_wide_hw_breakpoint);
if (!(flags & PERF_EF_START))
bp->hw.state = PERF_HES_STOPPED;
+ if (is_sampling_event(bp)) {
+ bp->hw.last_period = bp->hw.sample_period;
+ perf_swevent_set_period(bp);
+ }
+
return arch_install_hw_breakpoint(bp);
}
int __init init_hw_breakpoint(void)
{
- unsigned int **task_bp_pinned;
int cpu, err_cpu;
int i;
for_each_possible_cpu(cpu) {
for (i = 0; i < TYPE_MAX; i++) {
- task_bp_pinned = &per_cpu(nr_task_bp_pinned[i], cpu);
- *task_bp_pinned = kzalloc(sizeof(int) * nr_slots[i],
- GFP_KERNEL);
- if (!*task_bp_pinned)
+ struct bp_cpuinfo *info = get_bp_info(cpu, i);
+
+ info->tsk_pinned = kcalloc(nr_slots[i], sizeof(int),
+ GFP_KERNEL);
+ if (!info->tsk_pinned)
goto err_alloc;
}
}
err_alloc:
for_each_possible_cpu(err_cpu) {
for (i = 0; i < TYPE_MAX; i++)
- kfree(per_cpu(nr_task_bp_pinned[i], err_cpu));
+ kfree(get_bp_info(err_cpu, i)->tsk_pinned);
if (err_cpu == cpu)
break;
}
projects / cascardo / linux.git / blobdiff