diff options
Diffstat (limited to 'Documentation')
| -rw-r--r-- | Documentation/kernel-parameters.txt | 13 | ||||
| -rw-r--r-- | Documentation/trace/events.txt | 15 | ||||
| -rw-r--r-- | Documentation/trace/ftrace.txt | 13 |
3 files changed, 38 insertions, 3 deletions
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt index 75236f1972d9..15356aca938c 100644 --- a/Documentation/kernel-parameters.txt +++ b/Documentation/kernel-parameters.txt @@ -3081,6 +3081,19 @@ bytes respectively. Such letter suffixes can also be entirely omitted. See also Documentation/trace/ftrace.txt "trace options" section. + traceoff_on_warning + [FTRACE] enable this option to disable tracing when a + warning is hit. This turns off "tracing_on". Tracing can + be enabled again by echoing '1' into the "tracing_on" + file located in /sys/kernel/debug/tracing/ + + This option is useful, as it disables the trace before + the WARNING dump is called, which prevents the trace to + be filled with content caused by the warning output. + + This option can also be set at run time via the sysctl + option: kernel/traceoff_on_warning + transparent_hugepage= [KNL] Format: [always|madvise|never] diff --git a/Documentation/trace/events.txt b/Documentation/trace/events.txt index bb24c2a0e870..37732a220d33 100644 --- a/Documentation/trace/events.txt +++ b/Documentation/trace/events.txt @@ -183,13 +183,22 @@ The relational-operators depend on the type of the field being tested: The operators available for numeric fields are: -==, !=, <, <=, >, >= +==, !=, <, <=, >, >=, & And for string fields they are: -==, != +==, !=, ~ -Currently, only exact string matches are supported. +The glob (~) only accepts a wild card character (*) at the start and or +end of the string. For example: + + prev_comm ~ "*sh" + prev_comm ~ "sh*" + prev_comm ~ "*sh*" + +But does not allow for it to be within the string: + + prev_comm ~ "ba*sh" <-- is invalid 5.2 Setting filters ------------------- diff --git a/Documentation/trace/ftrace.txt b/Documentation/trace/ftrace.txt index bfe8c29b1f1d..b937c6e2163c 100644 --- a/Documentation/trace/ftrace.txt +++ b/Documentation/trace/ftrace.txt @@ -2430,6 +2430,19 @@ The following commands are supported: echo '!schedule:disable_event:sched:sched_switch' > \ set_ftrace_filter +- dump + When the function is hit, it will dump the contents of the ftrace + ring buffer to the console. This is useful if you need to debug + something, and want to dump the trace when a certain function + is hit. Perhaps its a function that is called before a tripple + fault happens and does not allow you to get a regular dump. + +- cpudump + When the function is hit, it will dump the contents of the ftrace + ring buffer for the current CPU to the console. Unlike the "dump" + command, it only prints out the contents of the ring buffer for the + CPU that executed the function that triggered the dump. + trace_pipe ---------- |