perf script -F <fields>

is equivalent to:

perf script -F trace:<fields> -F sw:<fields> -F hw:<fields>

i.e., the specified fields apply to all event types if the type string
is not given.

The arguments are processed in the order received. A later usage can
reset a prior request. e.g.:

-F trace: -F comm,tid,time,ip,sym

The first -F suppresses trace events (field list is ""), but then the
second invocation sets the fields to comm,tid,time,ip,sym. In this case a
warning is given to the user:

"Overriding previous field request for all events."

Alternatively, consider the order:

-F comm,tid,time,ip,sym -F trace:

The first -F sets the fields for all events and the second -F
suppresses trace events. The user is given a warning message about
the override, and the result of the above is that only S/W and H/W
events are displayed with the given fields.

For the 'wildcard' option if a user selected field is invalid for an
event type, a message is displayed to the user that the option is
ignored for that type. For example:

$ perf script -F comm,tid,trace
'trace' not valid for hardware events. Ignoring.
'trace' not valid for software events. Ignoring.

Alternatively, if the type is given an invalid field is specified it
is an error. For example:

perf script -v -F sw:comm,tid,trace
'trace' not valid for software events.

At this point usage is displayed, and perf-script exits.

The flags field is synthesized and may have a value when Instruction
Trace decoding. The flags are "bcrosyiABEx" which stand for branch,
call, return, conditional, system, asynchronous, interrupt,
transaction abort, trace begin, trace end, and in transaction,
respectively. Known combinations of flags are printed more nicely e.g.
"call" for "bc", "return" for "br", "jcc" for "bo", "jmp" for "b",
"int" for "bci", "iret" for "bri", "syscall" for "bcs", "sysret" for "brs",
"async" for "by", "hw int" for "bcyi", "tx abrt" for "bA", "tr strt" for "bB",
"tr end" for "bE". However the "x" flag will be display separately in those
cases e.g. "jcc     (x)" for a condition branch within a transaction.

The callindent field is synthesized and may have a value when
Instruction Trace decoding. For calls and returns, it will display the
name of the symbol indented with spaces to reflect the stack depth.

Finally, a user may not set fields to none for all event types.
i.e., -F "" is not allowed.

The brstack output includes branch related information with raw addresses using the
/v/v/v/v/ syntax in the following order:
FROM: branch source instruction
TO  : branch target instruction
M/P/-: M=branch target mispredicted or branch direction was mispredicted, P=target predicted or direction predicted, -=not supported
X/- : X=branch inside a transactional region, -=not in transaction region or not supported
A/- : A=TSX abort entry, -=not aborted region or not supported

The brstacksym is identical to brstack, except that the FROM and TO addresses are printed in a symbolic form if possible.

i       synthesize instructions events
b       synthesize branches events
c       synthesize branches events (calls only)
r       synthesize branches events (returns only)
x       synthesize transactions events
e       synthesize error events
d       create a debug log
g       synthesize a call chain (use with i or x)
l       synthesize last branch entries (use with i or x)
s       skip initial number of events

The default is all events i.e. the same as --itrace=ibxe

In addition, the period (default 100000) for instructions events
can be specified in units of:

i       instructions
t       ticks
ms      milliseconds
us      microseconds
ns      nanoseconds (default)

Also the call chain size (default 16, max. 1024) for instructions or
transactions events can be specified.

Also the number of last branch entries (default 64, max. 1024) for
instructions or transactions events can be specified.

It is also possible to skip events generated (instructions, branches, transactions)
at the beginning. This is useful to ignore initialization code.

--itrace=i0nss1000000

skips the first million instructions.

To disable decoding entirely, use --no-itrace.

Default: 127