struct ring_buffer_per_cpu {
int cpu;
atomic_t record_disabled;
+ atomic_t resize_disabled;
struct trace_buffer *buffer;
raw_spinlock_t reader_lock; /* serialize readers */
arch_spinlock_t lock;
unsigned flags;
int cpus;
atomic_t record_disabled;
- atomic_t resize_disabled;
cpumask_var_t cpumask;
struct lock_class_key *reader_lock_key;
size = nr_pages * BUF_PAGE_SIZE;
- /*
- * Don't succeed if resizing is disabled, as a reader might be
- * manipulating the ring buffer and is expecting a sane state while
- * this is true.
- */
- if (atomic_read(&buffer->resize_disabled))
- return -EBUSY;
-
/* prevent another thread from changing buffer sizes */
mutex_lock(&buffer->mutex);
+
if (cpu_id == RING_BUFFER_ALL_CPUS) {
+ /*
+ * Don't succeed if resizing is disabled, as a reader might be
+ * manipulating the ring buffer and is expecting a sane state while
+ * this is true.
+ */
+ for_each_buffer_cpu(buffer, cpu) {
+ cpu_buffer = buffer->buffers[cpu];
+ if (atomic_read(&cpu_buffer->resize_disabled)) {
+ err = -EBUSY;
+ goto out_err_unlock;
+ }
+ }
+
/* calculate the pages to update */
for_each_buffer_cpu(buffer, cpu) {
cpu_buffer = buffer->buffers[cpu];
if (nr_pages == cpu_buffer->nr_pages)
goto out;
+ /*
+ * Don't succeed if resizing is disabled, as a reader might be
+ * manipulating the ring buffer and is expecting a sane state while
+ * this is true.
+ */
+ if (atomic_read(&cpu_buffer->resize_disabled)) {
+ err = -EBUSY;
+ goto out_err_unlock;
+ }
+
cpu_buffer->nr_pages_to_update = nr_pages -
cpu_buffer->nr_pages;
free_buffer_page(bpage);
}
}
+ out_err_unlock:
mutex_unlock(&buffer->mutex);
return err;
}
iter->cpu_buffer = cpu_buffer;
- atomic_inc(&buffer->resize_disabled);
+ atomic_inc(&cpu_buffer->resize_disabled);
atomic_inc(&cpu_buffer->record_disabled);
return iter;
raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
atomic_dec(&cpu_buffer->record_disabled);
- atomic_dec(&cpu_buffer->buffer->resize_disabled);
+ atomic_dec(&cpu_buffer->resize_disabled);
kfree(iter->event);
kfree(iter);
}
if (!cpumask_test_cpu(cpu, buffer->cpumask))
return;
- atomic_inc(&buffer->resize_disabled);
+ atomic_inc(&cpu_buffer->resize_disabled);
atomic_inc(&cpu_buffer->record_disabled);
/* Make sure all commits have finished */
raw_spin_unlock_irqrestore(&cpu_buffer->reader_lock, flags);
atomic_dec(&cpu_buffer->record_disabled);
- atomic_dec(&buffer->resize_disabled);
+ atomic_dec(&cpu_buffer->resize_disabled);
}
EXPORT_SYMBOL_GPL(ring_buffer_reset_cpu);