Jin Yao <yao....@linux.intel.com> writes: > It is often useful to know the branch types while analyzing branch > data. For example, a call is very different from a conditional branch. > > Currently we have to look it up in binary while the binary may later > not be available and even the binary is available but user has to take > some time. It is very useful for user to check it directly in perf > report. > > Perf already has support for disassembling the branch instruction > to get the x86 branch type. > > To keep consistent on kernel and userspace and make the classification > more common, the patch adds the common branch type classification > in perf_event.h. > > The patch only defines a minimum but most common set of branch types. > > PERF_BR_UNKNOWN : unknown > PERF_BR_COND ：conditional > PERF_BR_UNCOND : unconditional > PERF_BR_IND : indirect > PERF_BR_CALL : function call > PERF_BR_IND_CALL : indirect function call > PERF_BR_RET : function return > PERF_BR_SYSCALL : syscall > PERF_BR_SYSRET : syscall return > PERF_BR_COND_CALL : conditional function call > PERF_BR_COND_RET : conditional function return > > The patch also adds a new field type (4 bits) in perf_branch_entry > to record the branch type. > > Since the disassembling of branch instruction needs some overhead, > a new PERF_SAMPLE_BRANCH_TYPE_SAVE is introduced to indicate if it > needs to disassemble the branch instruction and record the branch > type.
Acked-by: Michael Ellerman <m...@ellerman.id.au> (powerpc) If you like. cheers
