param1 and param2 are defined as formats for the PMU in:
/sys/bus/event_sources/devices/<pmu>/format/*
+ There are also some params which are not defined in .../<pmu>/format/*.
+ These params can be used to overload default config values per event.
+ Here is a list of the params.
+ - 'period': Set event sampling period
+ - 'freq': Set event sampling frequency
+ - 'time': Disable/enable time stamping. Acceptable values are 1 for
+ enabling time stamping. 0 for disabling time stamping.
+ The default is 1.
+ - 'call-graph': Disable/enable callgraph. Acceptable str are "fp" for
+ FP mode, "dwarf" for DWARF mode, "lbr" for LBR mode and
+ "no" for disable callgraph.
+ - 'stack-size': user stack size for dwarf mode
+ Note: If user explicitly sets options which conflict with the params,
+ the value set by the params will be overridden.
+
- a hardware breakpoint event in the form of '\mem:addr[/len][:access]'
where addr is the address in memory you want to break in.
Access is the memory access type (read, write, execute) it can
"perf report" to view group events together.
--filter=<filter>::
- Event filter.
+ Event filter. This option should follow a event selector (-e) which
+ selects tracepoint event(s). Multiple '--filter' options are combined
+ using '&&'.
+
+--exclude-perf::
+ Don't record events issued by perf itself. This option should follow
+ a event selector (-e) which selects tracepoint event(s). It adds a
+ filter expression 'common_pid != $PERFPID' to filters. If other
+ '--filter' exists, the new filter expression will be combined with
+ them by '&&'.
-a::
--all-cpus::
Number of mmap data pages (must be a power of two) or size
specification with appended unit character - B/K/M/G. The
size is rounded up to have nearest pages power of two value.
+ Also, by adding a comma, the number of mmap pages for AUX
+ area tracing can be specified.
--group::
Put all events in a single event group. This precedes the --event
--call-graph::
Setup and enable call-graph (stack chain/backtrace) recording,
- implies -g.
+ implies -g. Default is "fp".
Allows specifying "fp" (frame pointer) or "dwarf"
(DWARF's CFI - Call Frame Information) or "lbr"
In some systems, where binaries are build with gcc
--fomit-frame-pointer, using the "fp" method will produce bogus
call graphs, using "dwarf", if available (perf tools linked to
- the libunwind library) should be used instead.
+ the libunwind or libdw library) should be used instead.
Using the "lbr" method doesn't require any compiler options. It
will produce call graphs from the hardware LBR registers. The
main limition is that it is only available on new Intel
platforms, such as Haswell. It can only get user call chain. It
doesn't work with branch stack sampling at the same time.
+ When "dwarf" recording is used, perf also records (user) stack dump
+ when sampled. Default size of the stack dump is 8192 (bytes).
+ User can change the size by passing the size after comma like
+ "--call-graph dwarf,4096".
+
-q::
--quiet::
Don't print any message, useful for scripting.
-s::
--stat::
- Per thread counts.
+ Record per-thread event counts. Use it with 'perf report -T' to see
+ the values.
-d::
--data::
- Sample addresses.
+ Record the sample addresses.
-T::
--timestamp::
- Sample timestamps. Use it with 'perf report -D' to see the timestamps,
- for instance.
+ Record the sample timestamps. Use it with 'perf report -D' to see the
+ timestamps, for instance.
+
+-P::
+--period::
+ Record the sample period.
-n::
--no-samples::
- any_call: any function call or system call
- any_ret: any function return or system call return
- ind_call: any indirect branch
+ - call: direct calls, including far (to/from kernel) calls
- u: only when the branch target is at the user level
- k: only when the branch target is in the kernel
- hv: only when the target is at the hypervisor level
--intr-regs::
Capture machine state (registers) at interrupt, i.e., on counter overflows for
each sample. List of captured registers depends on the architecture. This option
-is off by default.
+is off by default. It is possible to select the registers to sample using their
+symbolic names, e.g. on x86, ax, si. To list the available registers use
+--intr-regs=\?. To name registers, pass a comma separated list such as
+--intr-regs=ax,bx. The list of register is architecture dependent.
+
--running-time::
Record running and enabled time for read events (:S)
CLOCK_MONOTONIC_RAW are supported, some events might also allow
CLOCK_BOOTTIME, CLOCK_REALTIME and CLOCK_TAI.
+-S::
+--snapshot::
+Select AUX area tracing Snapshot Mode. This option is valid only with an
+AUX area tracing event. Optionally the number of bytes to capture per
+snapshot can be specified. In Snapshot Mode, trace data is captured only when
+signal SIGUSR2 is received.
+
+--proc-map-timeout::
+When processing pre-existing threads /proc/XXX/mmap, it may take a long time,
+because the file may be huge. A time out is needed in such cases.
+This option sets the time out limit. The default value is 500 ms.
+
+--switch-events::
+Record context switch events i.e. events of type PERF_RECORD_SWITCH or
+PERF_RECORD_SWITCH_CPU_WIDE.
+
+--clang-path::
+Path to clang binary to use for compiling BPF scriptlets.
+
+--clang-opt::
+Options passed to clang when compiling BPF scriptlets.
+
SEE ALSO
--------
linkperf:perf-stat[1], linkperf:perf-list[1]
Code Review / kvmfornfv.git / blobdiff