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Diffstat (limited to 'stap.1.in')
| -rw-r--r-- | stap.1.in | 11 |
1 files changed, 11 insertions, 0 deletions
@@ -1055,6 +1055,17 @@ pool is large because individual uprobe objects are allocated for each process for each script-level probe. .PP +With scripts that contain probes on any interrupt path, it is possible that +those interrupts may occur in the middle of another probe handler. The probe +in the interrupt handler would be skipped in this case to avoid reentrance. +To work around this issue, execute stap with the option +.BR \-DINTERRUPTIBLE=0 +to mask interrupts throughout the probe handler. This does add some extra +overhead to the probes, but it may prevent reentrance for common problem +cases. However, probes in NMI handlers and in the callpath of the stap +runtime may still be skipped due to reentrance. + +.PP Multiple scripts can write data into a relay buffer concurrently. A host script provides an interface for accessing its relay buffer to guest scripts. Then, the output of the guests are merged into the output of the host. |