commit 2b97264f100bcd2f717b300bcbcf23f11869789d
author Yuto Kawamura <kawamuray.dadada@gmail.com> Thu Jan 14 21:14:12 2021 +0900
committer yonghong-song <ys114321@gmail.com> Fri Jan 15 11:08:15 2021 -0800
tree 96c72ea104493ec07ca2edba4756d7aed4a6b101
parent a9f97691519b5225fa8d9fb45b35ccf23e029f1c

tools/offcputime Filter out negative offcpu duration

tools/offcputime.py

diff --git a/tools/offcputime.py b/tools/offcputime.py
index 068c707..c1bf79c 100755
--- a/tools/offcputime.py
+++ b/tools/offcputime.py
@@ -146,8 +146,13 @@
     }
 
     // calculate current thread's delta time
-    u64 delta = bpf_ktime_get_ns() - *tsp;
+    u64 t_start = *tsp;
+    u64 t_end = bpf_ktime_get_ns();
     start.delete(&pid);
+    if (t_start > t_end) {
+        return 0;
+    }
+    u64 delta = t_end - t_start;
     delta = delta / 1000;
     if ((delta < MINBLOCK_US) || (delta > MAXBLOCK_US)) {
         return 0;