diff options
Diffstat (limited to 'lket.5.in')
| -rw-r--r-- | lket.5.in | 26 |
1 files changed, 6 insertions, 20 deletions
@@ -217,31 +217,17 @@ Data format is: .SH BACKTRACE -Some event hooks have the capability of print backtrace. But since -backtrace printing is costly, it is defaultly turned off. +You should use lket_backtrace() function to log backtrace for +different events. -To print backtrace, you can just add "backtrace=1" into the probes, e.g: +It's simple to log backtrace, e.g: .SAMPLE probe addevent.scsi.ioentry { - backtrace=1 + lket_backtrace() } .ESAMPLE -By default backtrace=0 - -Currently the following events could be able to print backtrace: -.SAMPLE -.BR addevent.ioscheduler.elv_next_request -.BR addevent.ioscheduler.elv_add_request -.BR addevent.netdev.transmit -.BR addevent.scsi.ioentry -.BR addevent.scsi.iodispatching -.BR addevent.tskdispatch.cpuidle -.BR addevent.syscall.entry -.BR addevent.syscall.return -.ESAMPLE - .SH TRACE DATA FORMAT By default, LKET will log the trace data in binary format. @@ -282,8 +268,8 @@ stap -e "probe addevent.syscall {}" -I /usr/local/share/systemtap/tapsets/LKET - To only probe syscall.entry: stap -e "probe addevent.syscall.entry {}" -I /usr/local/share/systemtap/tapsets/LKET -b -M .TP -To probe netdev transmition and print the backtrace: -stap -e "probe addevent.netdev.transmit { backtrace=1 }" -I /usr/local/share/systemtap/tapsets/LKET -b -M +To probe netdev transmition and log backtrace: +stap -e "probe addevent.netdev.transmit { lket_backtrace() }" -I /usr/local/share/systemtap/tapsets/LKET -b -M .SH SEE ALSO |