Hello, On Sat, Jul 13, 2024 at 10:25:11PM +0530, Athira Rajeev wrote: > 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, second patchset added support to use > raw instruction. With raw instruction, macros are added to extract opcode > and register fields. > Link to second patchset: > https://lore.kernel.org/all/20240506121906.76639-1-atraj...@linux.vnet.ibm.com/ > > 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 > > Second patchset used "objdump" again to read the raw instruction. > But since there is no need to disassemble and binary code can be read > directly from the DSO, third patchset (ie this patchset) uses below > apporach. The apporach preferred in powerpc to parse sample for data > type profiling in V3 patchset is: > - Read directly from DSO using dso__data_read_offset > - If that fails for any case, fallback to using libcapstone > - If libcapstone is not supported, approach will use objdump > > 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 and Christophe 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, below 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 handle state type regs array size for x86 and powerpc > - Patch 4 adds support to capture and parse raw instruction in powerpc > using dso__data_read_offset utility > - Patch 4 also adds logic to support using objdump when doing default "perf > report" or "perf annotate" since it that needs disassembled instruction. > - Patch 5 adds disasm_line__parse to parse raw instruction for powerpc > - Patch 6 update parameters for reg extract functions to use raw > instruction on powerpc > - Patch 7 updates ins__find to carry raw_insn and also adds parse > callback for memory instructions for powerpc > - Patch 8 add support to identify memory instructions of opcode 31 in > powerpc > - Patch 9 adds more instructions to support instruction tracking in powerpc > - Patch 10 and 11 handles instruction tracking for powerpc. > - Patch 12, 13 and 14 add support to use libcapstone in powerpc > - Patch 15 and patch 16 handles support to find global register variables > - PAtch 17 updates data type compare functions data_type_cmp and > sort__typeoff_sort to include var_name along with type_name in > comparison. > - Patch 18 handles insn-stat option for perf annotate > > Note: > - There are remaining unknowns (25%) as seen in annotate Instruction stats > below. > - This patchset is not tested on powerpc32. In next step of enhancements > along with handling remaining unknowns, plan to cover powerpc32 changes > based on how testing goes. > > 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 609, ok 446 (73.2%), bad 163 (26.8%) > > Name/opcode : Good Bad > ----------------------------------------------------------- > 58 : 323 80 > 32 : 49 43 > 34 : 33 11 > OP_31_XOP_LDX : 8 20 > 40 : 23 0 > OP_31_XOP_LWARX : 5 1 > OP_31_XOP_LWZX : 2 3 > OP_31_XOP_LDARX : 3 0 > 33 : 0 2 > OP_31_XOP_LBZX : 0 1 > OP_31_XOP_LWAX : 0 1 > OP_31_XOP_LHZX : 0 1 > > perf report logs: > ================= > > Total Lost Samples: 0 > > Samples: 1K of event 'mem-loads' > Event count (approx.): 937238 > > Overhead Data Type Data Type Offset > ........ ......... ................ > 48.60% (unknown) (unknown) +0 (no field) > 11.42% 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) > 2.69% struct paca_struct struct paca_struct +2808 (canary) > 2.68% struct paca_struct struct paca_struct +8 (paca_index) > 2.24% struct paca_struct struct paca_struct +48 (data_offset) > 1.43% long unsigned int long unsigned int +0 (no field) > 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) > 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) > 0.72% long long unsigned int long long unsigned int +0 (no field)
Thanks for your work! But I think you need to split the basic part and global register support part which needs more review. For the patch 1 to 14: Reviewed-by: Namhyung Kim <namhy...@kernel.org> Thanks, Namhyung > > Thanks > Athira Rajeev > > Changelog: > From v6 -> v7: > - Addressed review comments from Namhyung > Changed format string space to %-20s while printing > instruction stats in patch 18. > Use cmp_null in patch 17 while comparing var_name to > properly sort with correct order. > > From v5 -> v6: > - Addressed review comments from Namhyung > Conditionally define TYPE_STATE_MAX_REGS based on arch. > Added macro for defining width of the raw codes and spaces > in disasm_line__parse_powerpc. > Call disasm_line__parse from disasm_line__parse_powerpc > for generic code. > Renamed symbol__disassemble_dso to symbol__disassemble_raw. > Fixed find_data_type_global_reg to correclty free var_types > and change indent level. > Fixed data_type_cmp and sort__typeoff_sort to include var_name > in comparing data type entries. > > From v4 -> v5: > - Addressed review comments from Namhyung > Handle max number of type state regs as 16 for x86 and 32 for > powerpc. > Added generic support for objdump patch first and DSO read > optimisation next > combined patch 3 and patch 4 in patchseries V4 to one patch > Changed reference for "raw_insn" to use "u32" > Splitted "parse" callback patch changes and "ins__find" patch > changes into two > Instead of making weak function, added get_powerpc_regs to > extract register and offset fields for powerpc > - Addressed complation fail when "dwarf.h" is not present ie > elfutils devel is not present. Used includes for #ifdef HAVE_DWARF_SUPPORT > when including functions that use Dwarf references. Also > conditionally include some of the header files. > > From v3->v4: > - Addressed review comments from Ian by using capston_init from > "util/print_insn.c" instead of "open_capston_handle". > - Addressed review comment from Namhyung by moving "opcode" > field from "struct ins" to "struct disasm_line" > > From v2->v3: > - Addressed review comments from Christophe and Namhyung for V2 > - Changed the apporach in powerpc to parse sample for data > type profiling as: > Read directly from DSO using dso__data_read_offset > If that fails for any case, fallback to using libcapstone > If libcapstone is not supported, approach will use objdump > - Include instructions with opcode as 31 and correctly categorize > them as memory or arithmetic instructions. > - Include more instructions for instruction tracking in powerpc > > 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 (18): > 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: Update TYPE_STATE_MAX_REGS to include max of regs in > powerpc > tools/perf: Add disasm_line__parse to parse raw instruction for > powerpc > tools/perf: Add support to capture and parse raw instruction in > powerpc using dso__data_read_offset utility > tools/perf: Update parameters for reg extract functions to use raw > instruction on powerpc > tools/perf: Add parse function for memory instructions in powerpc > tools/perf: Add support to identify memory instructions of opcode 31 > in powerpc > tools/perf: Add some of the arithmetic instructions to support > instruction tracking in powerpc > tools/perf: Add more instructions for instruction tracking > tools/perf: Update instruction tracking for powerpc > tools/perf: Make capstone_init non-static so that it can be used > during symbol disassemble > tools/perf: Use capstone_init and remove open_capstone_handle from > disasm.c > tools/perf: Add support to use libcapstone in powerpc > 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/perf: Update data_type_cmp and sort__typeoff_sort function to > include var_name in comparison > tools/perf: Set instruction name to be used with insn-stat when using > raw instruction > > tools/include/linux/string.h | 2 + > tools/lib/string.c | 13 + > tools/perf/arch/arm64/annotate/instructions.c | 3 +- > .../arch/loongarch/annotate/instructions.c | 6 +- > .../perf/arch/powerpc/annotate/instructions.c | 254 ++++++++ > tools/perf/arch/powerpc/util/dwarf-regs.c | 53 ++ > tools/perf/arch/s390/annotate/instructions.c | 5 +- > tools/perf/arch/x86/annotate/instructions.c | 377 ++++++++++++ > tools/perf/builtin-annotate.c | 4 +- > tools/perf/util/annotate-data.c | 544 ++++-------------- > tools/perf/util/annotate-data.h | 83 +++ > tools/perf/util/annotate.c | 29 +- > tools/perf/util/annotate.h | 6 +- > tools/perf/util/disasm.c | 468 +++++++++++++-- > tools/perf/util/disasm.h | 19 +- > 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/print_insn.c | 15 +- > tools/perf/util/print_insn.h | 5 + > tools/perf/util/sort.c | 25 +- > tools/perf/util/sort.h | 1 + > 22 files changed, 1421 insertions(+), 505 deletions(-) > > -- > 2.43.0 >
