From nobody Thu Sep 18 05:26:21 2025 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 25E29C4332F for ; Sat, 10 Dec 2022 14:00:09 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S229796AbiLJOAG (ORCPT ); Sat, 10 Dec 2022 09:00:06 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:34904 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229876AbiLJN6a (ORCPT ); Sat, 10 Dec 2022 08:58:30 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 20032186F4 for ; Sat, 10 Dec 2022 05:58:28 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 85A91B82A35 for ; Sat, 10 Dec 2022 13:58:26 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 19156C433A4; Sat, 10 Dec 2022 13:58:25 +0000 (UTC) Received: from rostedt by gandalf.local.home with local (Exim 4.96) (envelope-from ) id 1p40My-000kms-0Q; Sat, 10 Dec 2022 08:58:24 -0500 Message-ID: <20221210135823.996525523@goodmis.org> User-Agent: quilt/0.66 Date: Sat, 10 Dec 2022 08:57:55 -0500 From: Steven Rostedt To: linux-kernel@vger.kernel.org Cc: Masami Hiramatsu , Andrew Morton , Tom Zanussi Subject: [for-next][PATCH 05/25] tracing: Add .percent suffix option to histogram values References: <20221210135750.425719934@goodmis.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" From: "Masami Hiramatsu (Google)" Add .percent suffix option to show the histogram values in percentage. This feature is useful when we need yo undersntand the overall trend for the histograms of large values. E.g. this shows the runtime percentage for each tasks. Reviewed-by: Tom Zanussi Tested-by: Tom Zanussi ------ # cd /sys/kernel/debug/tracing/ # echo hist:keys=3Dpid:vals=3Dhitcount,runtime.percent:sort=3Dpid > \ events/sched/sched_stat_runtime/trigger # sleep 10 # cat events/sched/sched_stat_runtime/hist # event histogram # # trigger info: hist:keys=3Dpid:vals=3Dhitcount,runtime.percent:sort=3Dpid= :size=3D2048 [active] # { pid: 8 } hitcount: 7 runtime (%): 4.14 { pid: 14 } hitcount: 5 runtime (%): 3.69 { pid: 16 } hitcount: 11 runtime (%): 3.41 { pid: 61 } hitcount: 41 runtime (%): 19.75 { pid: 65 } hitcount: 4 runtime (%): 1.48 { pid: 70 } hitcount: 6 runtime (%): 3.60 { pid: 72 } hitcount: 2 runtime (%): 1.10 { pid: 144 } hitcount: 10 runtime (%): 32.01 { pid: 151 } hitcount: 8 runtime (%): 22.66 { pid: 152 } hitcount: 2 runtime (%): 8.10 Totals: Hits: 96 Entries: 10 Dropped: 0 ----- Link: https://lore.kernel.org/linux-trace-kernel/166610813077.56030.4238090= 506973562347.stgit@devnote2 Signed-off-by: Masami Hiramatsu (Google) Reviewed-by: Tom Zanussi Tested-by: Tom Zanussi --- kernel/trace/trace.c | 3 +- kernel/trace/trace_events_hist.c | 90 +++++++++++++++++++++++++++----- 2 files changed, 78 insertions(+), 15 deletions(-) diff --git a/kernel/trace/trace.c b/kernel/trace/trace.c index 93a75a97118f..08e9568849b1 100644 --- a/kernel/trace/trace.c +++ b/kernel/trace/trace.c @@ -5724,7 +5724,8 @@ static const char readme_msg[] =3D "\t .syscall display a syscall id as a syscall name\n" "\t .log2 display log2 value rather than raw number\n" "\t .buckets=3Dsize display values in groups of size rather t= han raw number\n" - "\t .usecs display a common_timestamp in microseconds\n\n" + "\t .usecs display a common_timestamp in microseconds\n" + "\t .percent display a number of percentage value\n\n" "\t The 'pause' parameter can be used to pause an existing hist\n" "\t trigger or to start a hist trigger but not log any events\n" "\t until told to do so. 'continue' can be used to start or\n" diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_h= ist.c index 31d58ddcc1d9..35b0e956f06e 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -506,6 +506,7 @@ enum hist_field_flags { HIST_FIELD_FL_ALIAS =3D 1 << 16, HIST_FIELD_FL_BUCKET =3D 1 << 17, HIST_FIELD_FL_CONST =3D 1 << 18, + HIST_FIELD_FL_PERCENT =3D 1 << 19, }; =20 struct var_defs { @@ -1707,6 +1708,8 @@ static const char *get_hist_field_flags(struct hist_f= ield *hist_field) flags_str =3D "buckets"; else if (hist_field->flags & HIST_FIELD_FL_TIMESTAMP_USECS) flags_str =3D "usecs"; + else if (hist_field->flags & HIST_FIELD_FL_PERCENT) + flags_str =3D "percent"; =20 return flags_str; } @@ -2315,6 +2318,10 @@ parse_field(struct hist_trigger_data *hist_data, str= uct trace_event_file *file, if (ret || !(*buckets)) goto error; *flags |=3D HIST_FIELD_FL_BUCKET; + } else if (strncmp(modifier, "percent", 7) =3D=3D 0) { + if (*flags & (HIST_FIELD_FL_VAR | HIST_FIELD_FL_KEY)) + goto error; + *flags |=3D HIST_FIELD_FL_PERCENT; } else { error: hist_err(tr, HIST_ERR_BAD_FIELD_MODIFIER, errpos(modifier)); @@ -5291,33 +5298,69 @@ static void hist_trigger_print_key(struct seq_file = *m, seq_puts(m, "}"); } =20 +/* Get the 100 times of the percentage of @val in @total */ +static inline unsigned int __get_percentage(u64 val, u64 total) +{ + if (!total) + goto div0; + + if (val < (U64_MAX / 10000)) + return (unsigned int)div64_ul(val * 10000, total); + + total =3D div64_u64(total, 10000); + if (!total) + goto div0; + + return (unsigned int)div64_ul(val, total); +div0: + return val ? UINT_MAX : 0; +} + +static void hist_trigger_print_val(struct seq_file *m, unsigned int idx, + const char *field_name, unsigned long flags, + u64 *totals, struct tracing_map_elt *elt) +{ + u64 val =3D tracing_map_read_sum(elt, idx); + unsigned int pc; + + if (flags & HIST_FIELD_FL_PERCENT) { + pc =3D __get_percentage(val, totals[idx]); + if (pc =3D=3D UINT_MAX) + seq_printf(m, " %s (%%):[ERROR]", field_name); + else + seq_printf(m, " %s (%%): %3u.%02u", field_name, + pc / 100, pc % 100); + } else if (flags & HIST_FIELD_FL_HEX) { + seq_printf(m, " %s: %10llx", field_name, val); + } else { + seq_printf(m, " %s: %10llu", field_name, val); + } +} + static void hist_trigger_entry_print(struct seq_file *m, struct hist_trigger_data *hist_data, + u64 *totals, void *key, struct tracing_map_elt *elt) { const char *field_name; - unsigned int i; + unsigned int i =3D HITCOUNT_IDX; + unsigned long flags; =20 hist_trigger_print_key(m, hist_data, key, elt); =20 - seq_printf(m, " hitcount: %10llu", - tracing_map_read_sum(elt, HITCOUNT_IDX)); + /* At first, show the raw hitcount always */ + hist_trigger_print_val(m, i, "hitcount", 0, totals, elt); =20 for (i =3D 1; i < hist_data->n_vals; i++) { field_name =3D hist_field_name(hist_data->fields[i], 0); + flags =3D hist_data->fields[i]->flags; =20 - if (hist_data->fields[i]->flags & HIST_FIELD_FL_VAR || - hist_data->fields[i]->flags & HIST_FIELD_FL_EXPR) + if (flags & HIST_FIELD_FL_VAR || flags & HIST_FIELD_FL_EXPR) continue; =20 - if (hist_data->fields[i]->flags & HIST_FIELD_FL_HEX) { - seq_printf(m, " %s: %10llx", field_name, - tracing_map_read_sum(elt, i)); - } else { - seq_printf(m, " %s: %10llu", field_name, - tracing_map_read_sum(elt, i)); - } + seq_puts(m, " "); + hist_trigger_print_val(m, i, field_name, flags, totals, elt); } =20 print_actions(m, hist_data, elt); @@ -5330,7 +5373,8 @@ static int print_entries(struct seq_file *m, { struct tracing_map_sort_entry **sort_entries =3D NULL; struct tracing_map *map =3D hist_data->map; - int i, n_entries; + int i, j, n_entries; + u64 *totals =3D NULL; =20 n_entries =3D tracing_map_sort_entries(map, hist_data->sort_keys, hist_data->n_sort_keys, @@ -5338,11 +5382,29 @@ static int print_entries(struct seq_file *m, if (n_entries < 0) return n_entries; =20 + for (j =3D 0; j < hist_data->n_vals; j++) { + if (!(hist_data->fields[j]->flags & HIST_FIELD_FL_PERCENT)) + continue; + if (!totals) { + totals =3D kcalloc(hist_data->n_vals, sizeof(u64), + GFP_KERNEL); + if (!totals) { + n_entries =3D -ENOMEM; + goto out; + } + } + for (i =3D 0; i < n_entries; i++) + totals[j] +=3D tracing_map_read_sum( + sort_entries[i]->elt, j); + } + for (i =3D 0; i < n_entries; i++) - hist_trigger_entry_print(m, hist_data, + hist_trigger_entry_print(m, hist_data, totals, sort_entries[i]->key, sort_entries[i]->elt); =20 + kfree(totals); +out: tracing_map_destroy_sort_entries(sort_entries, n_entries); =20 return n_entries; --=20 2.35.1