The patchset from Namhyung added support for data type profiling in perf tool. This enabled support to associate PMU samples to data types they refer using DWARF debug information. With the upstream perf, currently it possible to run perf report or perf annotate to view the data type information on x86.
Initial patchset posted here had changes need to enable data type profiling support for powerpc. https://lore.kernel.org/all/6e09dc28-4a2e-49d8-a2b5-ffb3396a9...@csgroup.eu/T/ Main change were: 1. powerpc instruction nmemonic table to associate load/store instructions with move_ops which is use to identify if instruction is a memory access one. 2. To get register number and access offset from the given instruction, code uses fields from "struct arch" -> objump. Added entry for powerpc here. 3. A get_arch_regnum to return register number from the register name string. But the apporach used in the initial patchset used parsing of disassembled code which the current perf tool implementation does. Example: lwz r10,0(r9) This line "lwz r10,0(r9)" is parsed to extract instruction name, registers names and offset. Also to find whether there is a memory reference in the operands, "memory_ref_char" field of objdump is used. For x86, "(" is used as memory_ref_char to tackle instructions of the form "mov (%rax), %rcx". In case of powerpc, not all instructions using "(" are the only memory instructions. Example, above instruction can also be of extended form (X form) "lwzx r10,0,r19". Inorder to easy identify the instruction category and extract the source/target registers, this patchset adds support to use raw instruction. With raw instruction, macros are added to extract opcode and register fields. Example representation using --show-raw-insn in objdump gives result: 38 01 81 e8 ld r4,312(r1) Here "38 01 81 e8" is the raw instruction representation. In powerpc, this translates to instruction form: "ld RT,DS(RA)" and binary code as: _____________________________________ | 58 | RT | RA | DS | | ------------------------------------- 0 6 11 16 30 31 Patchset adds support to pick the opcode and reg fields from this raw/binary instruction code. This approach came in from review comment by Segher Boessenkool for the initial patchset. Apart from that, instruction tracking is enabled for powerpc and support function is added to find variables defined as registers Example, in powerpc, two registers are defined to represent variable: 1. r13: represents local_paca register struct paca_struct *local_paca asm("r13"); 2. r1: represents stack_pointer register void *__stack_pointer asm("r1"); These are handled in this patchset. - Patch 1 is to rearrange register state type structures to header file so that it can referred from other arch specific files - Patch 2 is to make instruction tracking as a callback to"struct arch" so that it can be implemented by other archs easily and defined in arch specific files - Patch 3 is to fix a small comment - Patch 4 adds support to capture and parse raw instruction in objdump by keeping existing approach intact. - Patch 5 update parameters for reg extract functions to use raw instruction on powerpc - Patch 6 and patch 7 handles instruction tracking for powerpc. - Patch 8 and Patch 8 handles support to find global register variables With the current patchset: ./perf record -a -e mem-loads sleep 1 ./perf report -s type,typeoff --hierarchy --group --stdio ./perf annotate --data-type --insn-stat perf annotate logs: Annotate Instruction stats total 562, ok 441 (78.5%), bad 121 (21.5%) Name : Good Bad ----------------------------------------------------------- ld : 313 54 lwz : 51 32 lbz : 31 5 ldx : 6 21 lhz : 23 0 lwa : 4 3 lwarx : 5 0 lwzx : 2 2 ldarx : 3 0 lwzu : 2 0 stdcx. : 0 1 nop : 0 1 ldu : 1 0 lbzx : 0 1 lwax : 0 1 perf report logs: # Samples: 1K of event 'mem-loads' # Event count (approx.): 937238 # # Overhead Data Type Data Type Offset # ........ ......... ................ # 48.81% (unknown) (unknown) +0 (no field) 12.85% long unsigned int long unsigned int +0 (current_stack_pointer) 4.68% struct paca_struct struct paca_struct +2312 (__current) 4.57% struct paca_struct struct paca_struct +2354 (irq_soft_mask) 2.68% struct paca_struct struct paca_struct +8 (paca_index) 2.64% struct paca_struct struct paca_struct +2808 (canary) 2.24% struct paca_struct struct paca_struct +48 (data_offset) 1.41% struct vm_fault struct vm_fault +0 (vma) 1.29% struct task_struct struct task_struct +276 (flags) 1.03% struct pt_regs struct pt_regs +264 (user_regs.msr) 1.00% struct menu_device struct menu_device +4 (tick_wakeup) 0.90% struct security_hook_list struct security_hook_list +0 (list.next) 0.76% struct irq_desc struct irq_desc +304 (irq_data.chip) 0.76% struct rq struct rq +2856 (cpu) Thanks Athira Rajeev Changelog: >From v1->v2: - Addressed suggestion from Christophe Leroy and Segher Boessenkool to use the binary code (raw insn) to fetch opcode, register and offset fields. - Added support for instruction tracking in powerpc - Find the register defined variables (r13 and r1 which points to local_paca and current_stack_pointer in powerpc) Athira Rajeev (9): tools/perf: Move the data structures related to register type to header file tools/perf: Add "update_insn_state" callback function to handle arch specific instruction tracking tools/perf: Fix a comment about multi_regs in extract_reg_offset function tools/perf: Add support to capture and parse raw instruction in objdump tools/perf: Update parameters for reg extract functions to use raw instruction on powerpc tools/perf: Update instruction tracking for powerpc tools/perf: Update instruction tracking with add instruction tools/perf: Add support to find global register variables using find_data_type_global_reg tools/perf: Add support for global_die to capture name of variable in case of register defined variable tools/include/linux/string.h | 2 + tools/lib/string.c | 13 + .../perf/arch/powerpc/annotate/instructions.c | 84 +++ tools/perf/arch/powerpc/util/dwarf-regs.c | 52 ++ tools/perf/arch/x86/annotate/instructions.c | 383 +++++++++++++ tools/perf/util/annotate-data.c | 519 +++--------------- tools/perf/util/annotate-data.h | 78 +++ tools/perf/util/annotate.c | 32 +- tools/perf/util/annotate.h | 1 + tools/perf/util/disasm.c | 109 +++- tools/perf/util/disasm.h | 17 +- tools/perf/util/dwarf-aux.c | 1 + tools/perf/util/dwarf-aux.h | 1 + tools/perf/util/include/dwarf-regs.h | 12 + tools/perf/util/sort.c | 7 +- 15 files changed, 854 insertions(+), 457 deletions(-) -- 2.43.0
