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Diffstat (limited to 'kernel/trace/ring_buffer.c')
-rw-r--r--kernel/trace/ring_buffer.c60
1 files changed, 29 insertions, 31 deletions
diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c
index 04bb94c29f58..9c4e40847e43 100644
--- a/kernel/trace/ring_buffer.c
+++ b/kernel/trace/ring_buffer.c
@@ -2380,6 +2380,9 @@ int ring_buffer_meta_seq_init(struct file *file, struct trace_buffer *buffer, in
struct seq_file *m;
int ret;
+ if (!cpumask_test_cpu(cpu, buffer->cpumask))
+ return -ENODEV;
+
ret = seq_open(file, &rb_meta_seq_ops);
if (ret)
return ret;
@@ -2440,22 +2443,33 @@ static int __rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
unsigned long nr_pages, struct list_head *pages)
{
struct trace_buffer *buffer = cpu_buffer->buffer;
+ unsigned int subbuf_order = buffer->subbuf_order;
struct ring_buffer_cpu_meta *meta = NULL;
struct buffer_page *bpage, *tmp;
- bool user_thread = current->mm != NULL;
struct ring_buffer_desc *desc = NULL;
+ bool user_thread = false;
long i;
- /*
- * Check if the available memory is there first.
- * Note, si_mem_available() only gives us a rough estimate of available
- * memory. It may not be accurate. But we don't care, we just want
- * to prevent doing any allocation when it is obvious that it is
- * not going to succeed.
- */
- i = si_mem_available();
- if (i < nr_pages)
- return -ENOMEM;
+ if (buffer->range_addr_start) {
+ meta = rb_range_meta(buffer, nr_pages, cpu_buffer->cpu);
+ } else if (buffer->remote) {
+ desc = ring_buffer_desc(buffer->remote->desc, cpu_buffer->cpu);
+ if (!desc || WARN_ON(desc->nr_page_va != (nr_pages + 1)))
+ return -EINVAL;
+ } else {
+ /*
+ * Check if the available memory is there first.
+ * Note, si_mem_available() only gives us a rough estimate of available
+ * memory. It may not be accurate. But we don't care, we just want
+ * to prevent doing any allocation when it is obvious that it is
+ * not going to succeed.
+ */
+ i = si_mem_available();
+ if (i < (nr_pages << subbuf_order))
+ return -ENOMEM;
+
+ user_thread = current->mm != NULL;
+ }
/*
* If a user thread allocates too much, and si_mem_available()
@@ -2469,15 +2483,6 @@ static int __rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
if (user_thread)
set_current_oom_origin();
- if (buffer->range_addr_start)
- meta = rb_range_meta(buffer, nr_pages, cpu_buffer->cpu);
-
- if (buffer->remote) {
- desc = ring_buffer_desc(buffer->remote->desc, cpu_buffer->cpu);
- if (!desc || WARN_ON(desc->nr_page_va != (nr_pages + 1)))
- return -EINVAL;
- }
-
for (i = 0; i < nr_pages; i++) {
bpage = alloc_cpu_page(cpu_buffer->cpu);
@@ -2513,12 +2518,11 @@ static int __rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer,
bpage->id = i + 1;
cpu_buffer->subbuf_ids[i + 1] = bpage;
} else {
- bpage->page = alloc_cpu_data(cpu_buffer->cpu,
- cpu_buffer->buffer->subbuf_order);
+ bpage->page = alloc_cpu_data(cpu_buffer->cpu, subbuf_order);
if (!bpage->page)
goto free_pages;
}
- bpage->order = cpu_buffer->buffer->subbuf_order;
+ bpage->order = subbuf_order;
if (user_thread && fatal_signal_pending(current))
goto free_pages;
@@ -3627,10 +3631,8 @@ static void rb_inc_iter(struct ring_buffer_iter *iter)
/* Return the index into the sub-buffers for a given sub-buffer */
static int rb_meta_subbuf_idx(struct ring_buffer_cpu_meta *meta, void *subbuf)
{
- void *subbuf_array;
+ void *subbuf_array = rb_subbufs_from_meta(meta);
- subbuf_array = (void *)meta + sizeof(int) * meta->nr_subbufs;
- subbuf_array = (void *)ALIGN((unsigned long)subbuf_array, meta->subbuf_size);
return (subbuf - subbuf_array) / meta->subbuf_size;
}
@@ -7997,12 +7999,8 @@ consume:
goto out;
}
- /* Did the reader catch up with the writer? */
- if (cpu_buffer->reader_page == cpu_buffer->commit_page)
- goto out;
-
reader = rb_get_reader_page(cpu_buffer);
- if (WARN_ON(!reader))
+ if (!reader)
goto out;
/* Check if any events were dropped */