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 48A38C433E6 for ; Fri, 12 Mar 2021 21:15:42 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 0E49B64F86 for ; Fri, 12 Mar 2021 21:15:42 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235198AbhCLVPQ (ORCPT ); Fri, 12 Mar 2021 16:15:16 -0500 Received: from mail.kernel.org ([198.145.29.99]:41998 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235179AbhCLVPH (ORCPT ); Fri, 12 Mar 2021 16:15:07 -0500 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 AAFB964FB2; Fri, 12 Mar 2021 21:15:06 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.94) (envelope-from ) id 1lKp7h-000LrI-LA; Fri, 12 Mar 2021 16:15:05 -0500 Message-ID: <20210312211505.535493567@goodmis.org> User-Agent: quilt/0.66 Date: Fri, 12 Mar 2021 16:13:58 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Ingo Molnar , Andrew Morton , "Zanussi, Tom" , Masami Hiramatsu , "Yordan Karadzhov" Subject: [PATCH 5/7] tracing: Use a no_filter_buffering_ref to stop using the filter buffer References: <20210312211353.422067021@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)" Currently, the trace histograms relies on it using absolute time stamps to trigger the tracing to not use the temp buffer if filters are set. That's because the histograms need the full timestamp that is saved in the ring buffer. That is no longer the case, as the ring_buffer_event_time_stamp() can now return the time stamp for all events without all triggering a full absolute time stamp. Now that the absolute time stamp is an unrelated dependency to not using the filters. There's nothing about having absolute timestamps to keep from using the filter buffer. Instead, change the interface to explicitly state to disable filter buffering that the histogram logic can use. Signed-off-by: Steven Rostedt (VMware) --- kernel/trace/trace.c | 28 ++++++++++++---------------- kernel/trace/trace.h | 4 ++-- kernel/trace/trace_events_hist.c | 6 +++--- 3 files changed, 17 insertions(+), 21 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index c138891eab86..8cf7397f3f56 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -2737,12 +2737,13 @@ trace_event_buffer_lock_reserve(struct trace_buffer **current_rb, unsigned int trace_ctx) { struct ring_buffer_event *entry; + struct trace_array *tr = trace_file->tr; int val; - *current_rb = trace_file->tr->array_buffer.buffer; + *current_rb = tr->array_buffer.buffer; - if (!ring_buffer_time_stamp_abs(*current_rb) && (trace_file->flags & - (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && + if (!tr->no_filter_buffering_ref && + (trace_file->flags & (EVENT_FILE_FL_SOFT_DISABLED | EVENT_FILE_FL_FILTERED)) && (entry = this_cpu_read(trace_buffered_event))) { /* Try to use the per cpu buffer first */ val = this_cpu_inc_return(trace_buffered_event_cnt); @@ -7119,31 +7120,26 @@ static int tracing_time_stamp_mode_open(struct inode *inode, struct file *file) return ret; } -int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs) +/* + * Set or disable using the per CPU trace_buffer_event when possible. + */ +int tracing_set_filter_buffering(struct trace_array *tr, bool set) { int ret = 0; mutex_lock(&trace_types_lock); - if (abs && tr->time_stamp_abs_ref++) + if (set && tr->no_filter_buffering_ref++) goto out; - if (!abs) { - if (WARN_ON_ONCE(!tr->time_stamp_abs_ref)) { + if (!set) { + if (WARN_ON_ONCE(!tr->no_filter_buffering_ref)) { ret = -EINVAL; goto out; } - if (--tr->time_stamp_abs_ref) - goto out; + --tr->no_filter_buffering_ref; } - - ring_buffer_set_time_stamp_abs(tr->array_buffer.buffer, abs); - -#ifdef CONFIG_TRACER_MAX_TRACE - if (tr->max_buffer.buffer) - ring_buffer_set_time_stamp_abs(tr->max_buffer.buffer, abs); -#endif out: mutex_unlock(&trace_types_lock); diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 16bedaaface4..de717706e863 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -352,7 +352,7 @@ struct trace_array { /* function tracing enabled */ int function_enabled; #endif - int time_stamp_abs_ref; + int no_filter_buffering_ref; struct list_head hist_vars; #ifdef CONFIG_TRACER_SNAPSHOT struct cond_snapshot *cond_snapshot; @@ -372,7 +372,7 @@ extern int tracing_check_open_get_tr(struct trace_array *tr); extern struct trace_array *trace_array_find(const char *instance); extern struct trace_array *trace_array_find_get(const char *instance); -extern int tracing_set_time_stamp_abs(struct trace_array *tr, bool abs); +extern int tracing_set_filter_buffering(struct trace_array *tr, bool set); extern int tracing_set_clock(struct trace_array *tr, const char *clockstr); extern bool trace_clock_in_ns(struct trace_array *tr); diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 05ead88cfb66..3090498acd98 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -5483,7 +5483,7 @@ static int hist_register_trigger(char *glob, struct event_trigger_ops *ops, goto out; } - tracing_set_time_stamp_abs(file->tr, true); + tracing_set_filter_buffering(file->tr, true); } if (named_data) @@ -5591,7 +5591,7 @@ static void hist_unregister_trigger(char *glob, struct event_trigger_ops *ops, if (hist_data->enable_timestamps) { if (!hist_data->remove || unregistered) - tracing_set_time_stamp_abs(file->tr, false); + tracing_set_filter_buffering(file->tr, false); } } @@ -5638,7 +5638,7 @@ static void hist_unreg_all(struct trace_event_file *file) update_cond_flag(file); if (hist_data->enable_timestamps) - tracing_set_time_stamp_abs(file->tr, false); + tracing_set_filter_buffering(file->tr, false); if (test->ops->free) test->ops->free(test->ops, test); } -- 2.30.1