perf list [hw|sw|cache|tracepoint|pmu|event_glob]
This command displays the symbolic event types which can be selected in the various perf commands with the -e option.
Events can optionally have a modifier by appending a colon and one or more modifiers. Modifiers allow the user to restrict the events to be counted. The following modifiers exist:
u - user-space counting k - kernel counting h - hypervisor counting I - non idle counting G - guest counting (in KVM guests) H - host counting (not in KVM guests) p - precise level P - use maximum detected precise level S - read sample value (PERF_SAMPLE_READ) D - pin the event to the PMU
The p modifier can be used for specifying how precise the instruction address should be. The p modifier can be specified multiple times:
0 - SAMPLE_IP can have arbitrary skid 1 - SAMPLE_IP must have constant skid 2 - SAMPLE_IP requested to have 0 skid 3 - SAMPLE_IP must have 0 skid, or uses randomization to avoid sample shadowing effects.
For Intel systems precise event sampling is implemented with PEBS which supports up to precise-level 2, and precise level 3 for some special cases
On AMD systems it is implemented using IBS (up to precise-level 2). The precise modifier works with event types 0x76 (cpu-cycles, CPU clocks not halted) and 0xC1 (micro-ops retired). Both events map to IBS execution sampling (IBS op) with the IBS Op Counter Control bit (IbsOpCntCtl) set respectively (see AMD64 Architecture Programmer's Manual Volume 2: System Programming, 13.3 Instruction-Based Sampling). Examples to use IBS:
perf record -a -e cpu-cycles:p ... # use ibs op counting cycles perf record -a -e r076:p ... # same as -e cpu-cycles:p perf record -a -e r0C1:p ... # use ibs op counting micro-ops
RAW HARDWARE EVENT DESCRIPTOR
Even when an event is not available in a symbolic form within perf right now, it can be encoded in a per processor specific way.
For instance For x86 CPUs NNN represents the raw register encoding with the layout of IA32_PERFEVTSELx MSRs (see [Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 3B: System Programming Guide] Figure 30-1 Layout of IA32_PERFEVTSELx MSRs) or AMD's PerfEvtSeln (see [AMD64 Architecture Programmer's Manual Volume 2: System Programming], Page 344, Figure 13-7 Performance Event-Select Register (PerfEvtSeln)).
Note: Only the following bit fields can be set in x86 counter registers: event, umask, edge, inv, cmask. Esp. guest/host only and OS/user mode flags must be setup using EVENT MODIFIERS.
If the Intel docs for a QM720 Core i7 describe an event as:
Event Umask Event Mask Num. Value Mnemonic Description Comment
A8H 01H LSD.UOPS Counts the number of micro-ops Use cmask=1 and delivered by loop stream detector invert to count cycles
raw encoding of 0x1A8 can be used:
perf stat -e r1a8 -a sleep 1 perf record -e r1a8 ...
You should refer to the processor specific documentation for getting these details. Some of them are referenced in the SEE ALSO section below.
Some pmu events listed by perf-list will be displayed with ? in them. For example:
This means that when provided as an event, a value for ? must also be supplied. For example:
perf stat -C 0 -e 'hv_gpci/dtbp_ptitc,phys_processor_idx=0x2/' ...
Without options all known events will be listed.
To limit the list use:
- 1. hw or hardware to list hardware events such as cache-misses, etc.
- 2. sw or software to list software events such as context switches, etc.
- 3. cache or hwcache to list hardware cache events such as L1-dcache-loads, etc.
- 4. tracepoint to list all tracepoint events, alternatively use subsys_glob:event_glob to filter by tracepoint subsystems such as sched, block, etc.
- 5. pmu to print the kernel supplied PMU events.
- 6. If none of the above is matched, it will apply the supplied glob to all events, printing the ones that match.
- 7. As a last resort, it will do a substring search in all event names.
One or more types can be used at the same time, listing the events for the types specified.
Support raw format:
- 1. --raw-dump, shows the raw-dump of all the events.
- 2. --raw-dump [hw|sw|cache|tracepoint|pmu|event_glob], shows the raw-dump of a certain kind of events.
- Intel® 64 and IA-32 Architectures Software Developer's Manual Volume 3B: System Programming Guide
AMD64 Architecture Programmer's Manual Volume 2: System Programming