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perf annotate: Add disasm_line__parse() to parse raw instruction for powerpc

Currently, the perf tool infrastructure uses the disasm_line__parse function to parse disassembled line. Example snippet from objdump: objdump --start-address=<address> --stop-address=<address> -d --no-show-raw-insn -C <vmlinux> c0000000010224b4: lwz r10,0(r9) This line "lwz r10,0(r9)" is parsed to extract instruction name, registers names and offset. In powerpc, the approach for data type profiling uses raw instruction instead of result from objdump to identify the instruction category and extract the source/target registers. Example: 38 01 81 e8 ld r4,312(r1) Here "38 01 81 e8" is the raw instruction representation. Add function "disasm_line__parse_powerpc" to handle parsing of raw instruction. Also update "struct disasm_line" to save the binary code/ With the change, function captures: line -> "38 01 81 e8 ld r4,312(r1)" raw instruction "38 01 81 e8" Raw instruction is used later to extract the reg/offset fields. Macros are added to extract opcode and register fields. "struct disasm_line" is updated to carry union of "bytes" and "raw_insn" of 32 bit to carry raw code (raw). Function "disasm_line__parse_powerpc fills the raw instruction hex value and can use macros to get opcode. There is no changes in existing code paths, which parses the disassembled code. The size of raw instruction depends on architecture. In case of powerpc, the parsing the disasm line needs to handle cases for reading binary code directly from DSO as well as parsing the objdump result. Hence adding the logic into separate function instead of updating "disasm_line__parse". The architecture using the instruction name and present approach is not altered. Since this approach targets powerpc, the macro implementation is added for powerpc as of now. Since the disasm_line__parse is used in other cases (perf annotate) and not only data tye profiling, the powerpc callback includes changes to work with binary code as well as mnemonic representation. Also in case if the DSO read fails and libcapstone is not supported, the approach fallback to use objdump as option. Hence as option, patch has changes to ensure objdump option also works well.

Athira Rajeev committed 2 years ago

Commit 06dd4c51 parent b1d8d966 files · +79 −2Browse files

Showing the changes to tools/include/linux/string.h (1 of 6 files). Show all

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tools/include/linux/string.h+2−0
@@ -46,5 +46,7 @@ extern char * __must_check skip_spaces(const char *); · 45 unmodified lines
46 46
47extern char *strim(char *);47extern char *strim(char *);
48 48
49extern void remove_spaces(char *s);
50
49extern void *memchr_inv(const void *start, int c, size_t bytes);51extern void *memchr_inv(const void *start, int c, size_t bytes);
50#endif /* _TOOLS_LINUX_STRING_H_ */52#endif /* _TOOLS_LINUX_STRING_H_ */

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