Re: [PATCH] ring-buffer: Include dropped pages in counting dirty patches

On Mon, 24 Oct 2022 22:13:28 +0900
Masami Hiramatsu (Google) [off-list ref] wrote:

quoted

@@ -2020,6 +2029,7 @@ rb_remove_pages(struct ring_buffer_per_cpu *cpu_buffer, unsigned long nr_pages)
 			 */
 			local_add(page_entries, &cpu_buffer->overrun);
 			local_sub(BUF_PAGE_SIZE, &cpu_buffer->entries_bytes);
+			local_inc(&cpu_buffer->pages_lost);  

Maybe we can make this part a static helper function so that we don't
repeat it below?

Makes sense. I'll send a v2.

-- Steve

quoted

 		}
 
 		/*

@@ -2504,6 +2514,7 @@ rb_handle_head_page(struct ring_buffer_per_cpu *cpu_buffer,
 		 */
 		local_add(entries, &cpu_buffer->overrun);
 		local_sub(BUF_PAGE_SIZE, &cpu_buffer->entries_bytes);
+		local_inc(&cpu_buffer->pages_lost);