From: "Masami Hiramatsu (Google)" <mhiramat@kernel.org>
Update histogram document for .percent/.graph suffixes and 'nohitcount'
option.
Link: https://lore.kernel.org/linux-trace-kernel/166610815604.56030.4124933216911828519.stgit@devnote2
Signed-off-by: Masami Hiramatsu (Google) <mhiramat@kernel.org>
Reviewed-by: Tom Zanussi <zanussi@kernel.org>
Tested-by: Tom Zanussi <zanussi@kernel.org>
---
Documentation/trace/histogram.rst | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)
@@ -25,7 +25,7 @@ Documentation written by Tom Zanussi
hist:keys=<field1[,field2,...]>[:values=<field1[,field2,...]>]
[:sort=<field1[,field2,...]>][:size=#entries][:pause][:continue]
- [:clear][:name=histname1][:<handler>.<action>] [if <filter>]
+ [:clear][:name=histname1][:nohitcount][:<handler>.<action>] [if <filter>]
When a matching event is hit, an entry is added to a hash table
using the key(s) and value(s) named. Keys and values correspond to
@@ -79,6 +79,8 @@ Documentation written by Tom Zanussi
.log2 display log2 value rather than raw number
.buckets=size display grouping of values rather than raw number
.usecs display a common_timestamp in microseconds
+ .percent display a number of percentage value
+ .graph display a bar-graph of a value
============= =================================================
Note that in general the semantics of a given field aren't
@@ -137,6 +139,12 @@ Documentation written by Tom Zanussi
existing trigger, rather than via the '>' operator, which will cause
the trigger to be removed through truncation.
+ The 'nohitcount' (or NOHC) parameter will suppress display of
+ raw hitcount in the histogram. This option requires at least one
+ value field which is not a 'raw hitcount'. For example,
+ 'hist:...:vals=hitcount:nohitcount' is rejected, but
+ 'hist:...:vals=hitcount.percent:nohitcount' is OK.
+
- enable_hist/disable_hist
The enable_hist and disable_hist triggers can be used to have one