From: Steven Rostedt <[email protected]> The function rb_allocate_pages() allocates cpu_buffer and on error needs to free it. It has a single return. Use __free(kfree) and return directly on errors and have the return use return_ptr(cpu_buffer).
The function alloc_buffer() allocates buffer and on error needs to free it. It has a single return. Use __free(kfree) and return directly on errors and have the return use return_ptr(buffer). The function __rb_map_vma() allocates a temporary array "pages". Have it use __free() and not worry about freeing it when returning. Signed-off-by: Steven Rostedt (Google) <[email protected]> --- kernel/trace/ring_buffer.c | 27 +++++++++------------------ 1 file changed, 9 insertions(+), 18 deletions(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index f3aa18c89166..10a4b26929ae 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -2226,7 +2226,7 @@ static int rb_allocate_pages(struct ring_buffer_per_cpu *cpu_buffer, static struct ring_buffer_per_cpu * rb_allocate_cpu_buffer(struct trace_buffer *buffer, long nr_pages, int cpu) { - struct ring_buffer_per_cpu *cpu_buffer; + struct ring_buffer_per_cpu *cpu_buffer __free(kfree) = NULL; struct ring_buffer_cpu_meta *meta; struct buffer_page *bpage; struct page *page; @@ -2252,7 +2252,7 @@ rb_allocate_cpu_buffer(struct trace_buffer *buffer, long nr_pages, int cpu) bpage = kzalloc_node(ALIGN(sizeof(*bpage), cache_line_size()), GFP_KERNEL, cpu_to_node(cpu)); if (!bpage) - goto fail_free_buffer; + return NULL; rb_check_bpage(cpu_buffer, bpage); @@ -2318,13 +2318,11 @@ rb_allocate_cpu_buffer(struct trace_buffer *buffer, long nr_pages, int cpu) rb_head_page_activate(cpu_buffer); } - return cpu_buffer; + return_ptr(cpu_buffer); fail_free_reader: free_buffer_page(cpu_buffer->reader_page); - fail_free_buffer: - kfree(cpu_buffer); return NULL; } @@ -2359,7 +2357,7 @@ static struct trace_buffer *alloc_buffer(unsigned long size, unsigned flags, unsigned long scratch_size, struct lock_class_key *key) { - struct trace_buffer *buffer; + struct trace_buffer *buffer __free(kfree) = NULL; long nr_pages; int subbuf_size; int bsize; @@ -2373,7 +2371,7 @@ static struct trace_buffer *alloc_buffer(unsigned long size, unsigned flags, return NULL; if (!zalloc_cpumask_var(&buffer->cpumask, GFP_KERNEL)) - goto fail_free_buffer; + return NULL; buffer->subbuf_order = order; subbuf_size = (PAGE_SIZE << order); @@ -2472,7 +2470,7 @@ static struct trace_buffer *alloc_buffer(unsigned long size, unsigned flags, mutex_init(&buffer->mutex); - return buffer; + return_ptr(buffer); fail_free_buffers: for_each_buffer_cpu(buffer, cpu) { @@ -2484,8 +2482,6 @@ static struct trace_buffer *alloc_buffer(unsigned long size, unsigned flags, fail_free_cpumask: free_cpumask_var(buffer->cpumask); - fail_free_buffer: - kfree(buffer); return NULL; } @@ -7076,7 +7072,7 @@ static int __rb_map_vma(struct ring_buffer_per_cpu *cpu_buffer, { unsigned long nr_subbufs, nr_pages, nr_vma_pages, pgoff = vma->vm_pgoff; unsigned int subbuf_pages, subbuf_order; - struct page **pages; + struct page **pages __free(kfree) = NULL; int p = 0, s = 0; int err; @@ -7144,10 +7140,8 @@ static int __rb_map_vma(struct ring_buffer_per_cpu *cpu_buffer, struct page *page; int off = 0; - if (WARN_ON_ONCE(s >= nr_subbufs)) { - err = -EINVAL; - goto out; - } + if (WARN_ON_ONCE(s >= nr_subbufs)) + return -EINVAL; page = virt_to_page((void *)cpu_buffer->subbuf_ids[s]); @@ -7162,9 +7156,6 @@ static int __rb_map_vma(struct ring_buffer_per_cpu *cpu_buffer, err = vm_insert_pages(vma, vma->vm_start, pages, &nr_pages); -out: - kfree(pages); - return err; } #else -- 2.47.2
