From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-13.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id D4822C433DB for ; Tue, 16 Mar 2021 16:42:31 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 96F6B6510C for ; Tue, 16 Mar 2021 16:42:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S238848AbhCPQmA (ORCPT ); Tue, 16 Mar 2021 12:42:00 -0400 Received: from mail.kernel.org ([198.145.29.99]:43968 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S238780AbhCPQlP (ORCPT ); Tue, 16 Mar 2021 12:41:15 -0400 Received: from gandalf.local.home (cpe-66-24-58-225.stny.res.rr.com [66.24.58.225]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.kernel.org (Postfix) with ESMTPSA id 8031265110; Tue, 16 Mar 2021 16:41:14 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94) (envelope-from ) id 1lMCkr-000lwj-Gi; Tue, 16 Mar 2021 12:41:13 -0400 Message-ID: <20210316164113.399089673@goodmis.org> User-Agent: quilt/0.66 Date: Tue, 16 Mar 2021 12:41:02 -0400 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , "Zanussi, Tom" , Tom Zanussi , Masami Hiramatsu , "Yordan Karadzhov" Subject: [PATCH 2/7 v2] ring-buffer: Add a event_stamp to cpu_buffer for each level of nesting References: <20210316164100.546961804@goodmis.org> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "Steven Rostedt (VMware)" Add a place to save the current event time stamp for each level of nesting. This will be used to retrieve the time stamp of the current event before it is committed. Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/ring_buffer.c | 11 ++++++++++- 1 file changed, 10 insertions(+), 1 deletion(-) diff --git a/kernel/trace/ring_buffer.c b/kernel/trace/ring_buffer.c index 941ac2021b97..470d97169081 100644 --- a/kernel/trace/ring_buffer.c +++ b/kernel/trace/ring_buffer.c @@ -492,6 +492,8 @@ struct rb_time_struct { #endif typedef struct rb_time_struct rb_time_t; +#define MAX_NEST 5 + /* * head_page == tail_page && head == tail then buffer is empty. */ @@ -529,6 +531,7 @@ struct ring_buffer_per_cpu { unsigned long read_bytes; rb_time_t write_stamp; rb_time_t before_stamp; + u64 event_stamp[MAX_NEST]; u64 read_stamp; /* ring buffer pages to update, > 0 to add, < 0 to remove */ long nr_pages_to_update; @@ -2715,6 +2718,10 @@ rb_update_event(struct ring_buffer_per_cpu *cpu_buffer, { unsigned length = info->length; u64 delta = info->delta; + unsigned int nest = local_read(&cpu_buffer->committing) - 1; + + if (nest < MAX_NEST) + cpu_buffer->event_stamp[nest] = info->ts; /* * If we need to add a timestamp, then we @@ -3456,7 +3463,6 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer, info->after, ts)) { /* Nothing came after this event between C and E */ info->delta = ts - info->after; - info->ts = ts; } else { /* * Interrupted between C and E: @@ -3468,6 +3474,7 @@ __rb_reserve_next(struct ring_buffer_per_cpu *cpu_buffer, */ info->delta = 0; } + info->ts = ts; info->add_timestamp &= ~RB_ADD_STAMP_FORCE; } @@ -5026,6 +5033,8 @@ rb_reset_cpu(struct ring_buffer_per_cpu *cpu_buffer) rb_time_set(&cpu_buffer->write_stamp, 0); rb_time_set(&cpu_buffer->before_stamp, 0); + memset(cpu_buffer->event_stamp, 0, sizeof(cpu_buffer->event_stamp)); + cpu_buffer->lost_events = 0; cpu_buffer->last_overrun = 0; -- 2.30.1