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-rw-r--r--kernel/events/ring_buffer.c84
1 files changed, 40 insertions, 44 deletions
diff --git a/kernel/events/ring_buffer.c b/kernel/events/ring_buffer.c
index 4a9937076331..674b35383491 100644
--- a/kernel/events/ring_buffer.c
+++ b/kernel/events/ring_buffer.c
@@ -1,3 +1,4 @@
+// SPDX-License-Identifier: GPL-2.0
/*
* Performance events ring-buffer code:
*
@@ -5,8 +6,6 @@
* Copyright (C) 2008-2011 Red Hat, Inc., Ingo Molnar
* Copyright (C) 2008-2011 Red Hat, Inc., Peter Zijlstra
* Copyright © 2009 Paul Mackerras, IBM Corp. <paulus@au1.ibm.com>
- *
- * For licensing details see kernel-base/COPYING
*/
#include <linux/perf_event.h>
@@ -285,7 +284,7 @@ ring_buffer_init(struct ring_buffer *rb, long watermark, int flags)
else
rb->overwrite = 1;
- atomic_set(&rb->refcount, 1);
+ refcount_set(&rb->refcount, 1);
INIT_LIST_HEAD(&rb->event_list);
spin_lock_init(&rb->event_lock);
@@ -358,7 +357,7 @@ void *perf_aux_output_begin(struct perf_output_handle *handle,
if (!atomic_read(&rb->aux_mmap_count))
goto err;
- if (!atomic_inc_not_zero(&rb->aux_refcount))
+ if (!refcount_inc_not_zero(&rb->aux_refcount))
goto err;
/*
@@ -393,7 +392,7 @@ void *perf_aux_output_begin(struct perf_output_handle *handle,
* store that will be enabled on successful return
*/
if (!handle->size) { /* A, matches D */
- event->pending_disable = 1;
+ event->pending_disable = smp_processor_id();
perf_output_wakeup(handle);
local_set(&rb->aux_nest, 0);
goto err_put;
@@ -456,24 +455,21 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
rb->aux_head += size;
}
- if (size || handle->aux_flags) {
- /*
- * Only send RECORD_AUX if we have something useful to communicate
- *
- * Note: the OVERWRITE records by themselves are not considered
- * useful, as they don't communicate any *new* information,
- * aside from the short-lived offset, that becomes history at
- * the next event sched-in and therefore isn't useful.
- * The userspace that needs to copy out AUX data in overwrite
- * mode should know to use user_page::aux_head for the actual
- * offset. So, from now on we don't output AUX records that
- * have *only* OVERWRITE flag set.
- */
-
- if (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE)
- perf_event_aux_event(handle->event, aux_head, size,
- handle->aux_flags);
- }
+ /*
+ * Only send RECORD_AUX if we have something useful to communicate
+ *
+ * Note: the OVERWRITE records by themselves are not considered
+ * useful, as they don't communicate any *new* information,
+ * aside from the short-lived offset, that becomes history at
+ * the next event sched-in and therefore isn't useful.
+ * The userspace that needs to copy out AUX data in overwrite
+ * mode should know to use user_page::aux_head for the actual
+ * offset. So, from now on we don't output AUX records that
+ * have *only* OVERWRITE flag set.
+ */
+ if (size || (handle->aux_flags & ~(u64)PERF_AUX_FLAG_OVERWRITE))
+ perf_event_aux_event(handle->event, aux_head, size,
+ handle->aux_flags);
rb->user_page->aux_head = rb->aux_head;
if (rb_need_aux_wakeup(rb))
@@ -481,7 +477,7 @@ void perf_aux_output_end(struct perf_output_handle *handle, unsigned long size)
if (wakeup) {
if (handle->aux_flags & PERF_AUX_FLAG_TRUNCATED)
- handle->event->pending_disable = 1;
+ handle->event->pending_disable = smp_processor_id();
perf_output_wakeup(handle);
}
@@ -599,29 +595,26 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
{
bool overwrite = !(flags & RING_BUFFER_WRITABLE);
int node = (event->cpu == -1) ? -1 : cpu_to_node(event->cpu);
- int ret = -ENOMEM, max_order = 0;
+ int ret = -ENOMEM, max_order;
if (!has_aux(event))
return -EOPNOTSUPP;
- if (event->pmu->capabilities & PERF_PMU_CAP_AUX_NO_SG) {
- /*
- * We need to start with the max_order that fits in nr_pages,
- * not the other way around, hence ilog2() and not get_order.
- */
- max_order = ilog2(nr_pages);
+ /*
+ * We need to start with the max_order that fits in nr_pages,
+ * not the other way around, hence ilog2() and not get_order.
+ */
+ max_order = ilog2(nr_pages);
- /*
- * PMU requests more than one contiguous chunks of memory
- * for SW double buffering
- */
- if ((event->pmu->capabilities & PERF_PMU_CAP_AUX_SW_DOUBLEBUF) &&
- !overwrite) {
- if (!max_order)
- return -EINVAL;
+ /*
+ * PMU requests more than one contiguous chunks of memory
+ * for SW double buffering
+ */
+ if (!overwrite) {
+ if (!max_order)
+ return -EINVAL;
- max_order--;
- }
+ max_order--;
}
rb->aux_pages = kcalloc_node(nr_pages, sizeof(void *), GFP_KERNEL,
@@ -658,7 +651,7 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
goto out;
}
- rb->aux_priv = event->pmu->setup_aux(event->cpu, rb->aux_pages, nr_pages,
+ rb->aux_priv = event->pmu->setup_aux(event, rb->aux_pages, nr_pages,
overwrite);
if (!rb->aux_priv)
goto out;
@@ -671,7 +664,7 @@ int rb_alloc_aux(struct ring_buffer *rb, struct perf_event *event,
* we keep a refcount here to make sure either of the two can
* reference them safely.
*/
- atomic_set(&rb->aux_refcount, 1);
+ refcount_set(&rb->aux_refcount, 1);
rb->aux_overwrite = overwrite;
rb->aux_watermark = watermark;
@@ -690,7 +683,7 @@ out:
void rb_free_aux(struct ring_buffer *rb)
{
- if (atomic_dec_and_test(&rb->aux_refcount))
+ if (refcount_dec_and_test(&rb->aux_refcount))
__rb_free_aux(rb);
}
@@ -734,6 +727,9 @@ struct ring_buffer *rb_alloc(int nr_pages, long watermark, int cpu, int flags)
size = sizeof(struct ring_buffer);
size += nr_pages * sizeof(void *);
+ if (order_base_2(size) >= PAGE_SHIFT+MAX_ORDER)
+ goto fail;
+
rb = kzalloc(size, GFP_KERNEL);
if (!rb)
goto fail;
generated by cgit v1.2.3 (git 2.0.4) at 2025-11-25 22:31:55 +0000