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1a891cf19c
There are some cases when filtering on a set flag of a field of a tracepoint is useful. But currently the only filtering commands for numbered fields is ==, !=, <, <=, >, >=. This does not help when you just want to trace if a specific flag is set. For example: > # sudo trace-cmd record -e brcmfmac:brcmf_dbg -f 'level & 0x40000' > disable all > enable brcmfmac:brcmf_dbg > path = /sys/kernel/debug/tracing/events/brcmfmac/brcmf_dbg/enable > (level & 0x40000) > ^ > parse_error: Invalid operator > When trying to trace brcmf_dbg when level has its 1 << 18 bit set, the filter fails to perform. By allowing a binary '&' operation, this gives the user the ability to test a bit. Note, a binary '|' is not added, as it doesn't make sense as fields must be compared to constants (for now), and ORing a constant will always return true. Link: http://lkml.kernel.org/r/1371057385.9844.261.camel@gandalf.local.home Suggested-by: Arend van Spriel <arend@broadcom.com> Tested-by: Arend van Spriel <arend@broadcom.com> Signed-off-by: Steven Rostedt <rostedt@goodmis.org> |
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| .. | ||
| postprocess | ||
| events-kmem.txt | ||
| events-power.txt | ||
| events.txt | ||
| ftrace-design.txt | ||
| ftrace.txt | ||
| function-graph-fold.vim | ||
| kprobetrace.txt | ||
| mmiotrace.txt | ||
| ring-buffer-design.txt | ||
| tracepoint-analysis.txt | ||
| tracepoints.txt | ||
| uprobetracer.txt | ||