Bug 26397 - Modern kernels no longer use cputime for task->utime and task->stime
Summary: Modern kernels no longer use cputime for task->utime and task->stime
Status: UNCONFIRMED
Alias: None
Product: systemtap
Classification: Unclassified
Component: tapsets (show other bugs)
Version: unspecified
: P2 normal
Target Milestone: ---
Assignee: Unassigned
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Blocks:
 
Reported: 2020-08-16 20:09 UTC by agentzh
Modified: 2020-08-16 20:09 UTC (History)
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Description agentzh 2020-08-16 20:09:00 UTC 
The task_time_string() tapset function assumes task->{utime,stime} to be cputime (or jiffies), which leads to very wrong results being returned. Modern kernels already use nanoseconds for these two fields.
Comment 1 agentzh 2020-08-16 20:09:55 UTC 
Not sure how to add a stap feature test for this kernel change.