linux-kernel - [PATCH V4 13/15] perf top: remove lost events checking

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite for Android: free password hash cracker in your pocket

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Date:   Mon, 15 Jan 2018 12:20:49 -0800
From:   kan.liang@...el.com
To:     acme@...nel.org, peterz@...radead.org, mingo@...hat.com,
        linux-kernel@...r.kernel.org
Cc:     wangnan0@...wei.com, jolsa@...nel.org, namhyung@...nel.org,
        ak@...ux.intel.com, yao.jin@...ux.intel.com,
        Kan Liang <kan.liang@...el.com>
Subject: [PATCH V4 13/15] perf top: remove lost events checking

From: Kan Liang <kan.liang@...el.com>

There would be some records lost in overwrite mode because of pausing
the ringbuffer. It has little impact for the accuracy of the snapshot
and could be tolerant for perf top.

The lost events checking is removed.

Signed-off-by: Kan Liang <kan.liang@...el.com>
---
 tools/perf/builtin-top.c | 8 +++++---
 1 file changed, 5 insertions(+), 3 deletions(-)

diff --git a/tools/perf/builtin-top.c b/tools/perf/builtin-top.c
index fc3c91b..3f10304 100644
--- a/tools/perf/builtin-top.c
+++ b/tools/perf/builtin-top.c
@@ -283,8 +283,9 @@ static void perf_top__print_sym_table(struct perf_top *top)
 
 	printf("%-*.*s\n", win_width, win_width, graph_dotted_line);
 
-	if (hists->stats.nr_lost_warned !=
-	    hists->stats.nr_events[PERF_RECORD_LOST]) {
+	if (!top->record_opts.overwrite &&
+	    (hists->stats.nr_lost_warned !=
+	    hists->stats.nr_events[PERF_RECORD_LOST])) {
 		hists->stats.nr_lost_warned =
 			      hists->stats.nr_events[PERF_RECORD_LOST];
 		color_fprintf(stdout, PERF_COLOR_RED,
@@ -611,7 +612,8 @@ static void *display_thread_tui(void *arg)
 
 	perf_evlist__tui_browse_hists(top->evlist, help, &hbt,
 				      top->min_percent,
-				      &top->session->header.env, false);
+				      &top->session->header.env,
+				      top->record_opts.overwrite);
 
 	done = 1;
 	return NULL;
-- 
2.5.5