Bug 2685 - need to skip probes on insufficient stack
Summary: need to skip probes on insufficient stack
Status: RESOLVED FIXED
Alias: None
Product: systemtap
Classification: Unclassified
Component: translator (show other bugs)
Version: unspecified
: P2 normal
Target Milestone: ---
Assignee: Frank Ch. Eigler
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2006-05-22 18:19 UTC by Frank Ch. Eigler
Modified: 2006-11-26 23:28 UTC (History)
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Description Frank Ch. Eigler 2006-05-22 18:19:41 UTC 
Similarly to bug #2185, because we don't have a separate stack for kprobe
handling (bug #931), we may have stack exhaustion problems in ordinary usage
without reentrancy.  We go out of our way to minimize stack usage, but we need to
- estimate or measure stack usage of a worst-case scenario (kprobes handler,
deeply nested systemtap expression, calling into the most complex runtime routine)
- add code to the probe entry functions to check for available stack space, and
punt (skip probe) if it's not sufficient
Comment 1 Frank Ch. Eigler 2006-11-26 23:28:56 UTC 
patch committed.  The default MINSTACKSPACE may need to be tuned in the future.