Bug 11759 - use raw_* synch objects on CONFIG_PREEMPT_RT kernels
Summary: use raw_* synch objects on CONFIG_PREEMPT_RT kernels
Status: RESOLVED WONTFIX
Alias: None
Product: systemtap
Classification: Unclassified
Component: runtime (show other bugs)
Version: unspecified
: P2 normal
Target Milestone: ---
Assignee: Frank Ch. Eigler
URL:
Keywords:
Depends on:
Blocks:
 
Reported: 2010-06-26 20:16 UTC by Frank Ch. Eigler
Modified: 2012-01-26 19:56 UTC (History)
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Description Frank Ch. Eigler 2010-06-26 20:16:38 UTC 
There have been reported crashes/hangs with the ordinary
rwlock / spinlocks used by the runtime/translator in the
generated systemtap modules.  Changing them all to the 
raw_* variants makes stap work on preempt-rt.  There may
exist performance/latency drawbacks to this transform,
but we can investigate those as data appears.
Comment 1 Frank Ch. Eigler 2010-06-26 20:19:33 UTC 
commit 8e49e02
Comment 2 Frank Ch. Eigler 2010-06-27 14:25:21 UTC 
some more to do
Comment 3 Frank Ch. Eigler 2012-01-26 19:56:18 UTC 
It turns out that more recent -rt kernels abhor the
simpleminded use of raw_* locking doodads, and work
fine with the normal kinds in our runtime.  So 
bug #13513 undid this stuff, and there was much
rejoicing.  Yea.