diff options
Diffstat (limited to 'Documentation/trace/histogram.rst')
| -rw-r--r-- | Documentation/trace/histogram.rst | 22 |
1 files changed, 20 insertions, 2 deletions
diff --git a/Documentation/trace/histogram.rst b/Documentation/trace/histogram.rst index 8408670d0328..b71e09f745c3 100644 --- a/Documentation/trace/histogram.rst +++ b/Documentation/trace/histogram.rst @@ -1495,7 +1495,7 @@ Extended error information # { stacktrace: - _do_fork+0x18e/0x330 + kernel_clone+0x18e/0x330 kernel_thread+0x29/0x30 kthreadd+0x154/0x1b0 ret_from_fork+0x3f/0x70 @@ -1588,7 +1588,7 @@ Extended error information SYSC_sendto+0xef/0x170 } hitcount: 88 { stacktrace: - _do_fork+0x18e/0x330 + kernel_clone+0x18e/0x330 SyS_clone+0x19/0x20 entry_SYSCALL_64_fastpath+0x12/0x6a } hitcount: 244 @@ -1776,6 +1776,24 @@ consisting of the name of the new event along with one or more variables and their types, which can be any valid field type, separated by semicolons, to the tracing/synthetic_events file. +See synth_field_size() for available types. + +If field_name contains [n], the field is considered to be a static array. + +If field_names contains[] (no subscript), the field is considered to +be a dynamic array, which will only take as much space in the event as +is required to hold the array. + +A string field can be specified using either the static notation: + + char name[32]; + +Or the dynamic: + + char name[]; + +The size limit for either is 256. + For instance, the following creates a new event named 'wakeup_latency' with 3 fields: lat, pid, and prio. Each of those fields is simply a variable reference to a variable on another event:: |