kernel/linux.git/tools/perf/util/annotate.h, branch v6.12.80

perf annotate: Display the branch counter histogram

2024-08-14T13:20:40+00:00

Display the branch counter histogram in the annotation view. Press 'B' to display the branch counter's abbreviation list as well. Samples: 1M of events 'anon group { branch-instructions:ppp, branch-misses }', 4000 Hz, Event count (approx.): f3 /home/sdp/test/tchain_edit [Percent: local period] Percent │ IPC Cycle Branch Counter (Average IPC: 1.39, IPC Coverage: 29.4%) │ 0000000000401755 : 0.00 0.00 │ endbr64 │ push %rbp │ mov %rsp,%rbp │ movl $0x0,-0x4(%rbp) 0.00 0.00 │1.33 3 |A |- | ↓ jmp 25 11.03 11.03 │ 11: mov -0x4(%rbp),%eax │ and $0x1,%eax │ test %eax,%eax 17.13 17.13 │2.41 1 |A |- | ↓ je 21 │ addl $0x1,-0x4(%rbp) 21.84 21.84 │2.22 2 |AA |- | ↓ jmp 25 17.13 17.13 │ 21: addl $0x1,-0x4(%rbp) 21.84 21.84 │ 25: cmpl $0x270f,-0x4(%rbp) 11.03 11.03 │0.61 3 |A |- | ↑ jle 11 │ nop │ pop %rbp 0.00 0.00 │0.24 20 |AA |B | ← ret Originally-by: Tinghao Zhang Reviewed-by: Andi Kleen Signed-off-by: Kan Liang Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20240813160208.2493643-8-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf report: Display the branch counter histogram

2024-08-14T13:20:40+00:00

Reusing the existing --total-cycles option to display the branch counters. Add a new PERF_HPP_REPORT__BLOCK_BRANCH_COUNTER to display the logged branch counter events. They are shown right after all the cycle-related annotations. Extend the 'struct block_info' to store and pass the branch counter related information. The annotation_br_cntr_entry() is to print the histogram of each branch counter event. If the number of logged events is less than 4, the exact number of the abbr name is printed. Otherwise, using '+' to stands for more than 3 events. Assume the number of logged events is less than 4. The annotation_br_cntr_abbr_list() prints the branch counter's abbreviation list. Press 'B' to display the list in the TUI mode. $ perf record -e "{branch-instructions:ppp,branch-misses}:S" -j any,counter $ perf report --total-cycles --stdio # To display the perf.data header info, please use --header/--header-only options. # # # Total Lost Samples: 0 # # Samples: 1M of events 'anon group { branch-instructions:ppp, branch-misses }' # Event count (approx.): 1610046 # # Branch counter abbr list: # branch-instructions:ppp = A # branch-misses = B # '-' No event occurs # '+' Event occurrences may be lost due to branch counter saturated # # Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter [Program Block Range] # ............... .............. ........... .......... .............. .................. # 57.55% 2.5M 0.00% 3 |A |- | ... 25.27% 1.1M 0.00% 2 |AA |- | ... 15.61% 667.2K 0.00% 1 |A |- | ... 0.16% 6.9K 0.81% 575 |A |- | ... 0.16% 6.8K 1.38% 977 |AA |- | ... 0.16% 6.8K 0.04% 28 |AA |B | ... 0.15% 6.6K 1.33% 946 |A |- | ... 0.11% 4.5K 0.06% 46 |AAA+|- | ... 0.10% 4.4K 0.88% 624 |A |- | ... 0.09% 3.7K 0.74% 524 |AAA+|B | ... With -v applied, # Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter [Program Block Range] # ............... .............. ........... .......... .............. .................. # 57.55% 2.5M 0.00% 3 A=1 ,B=- ... 25.27% 1.1M 0.00% 2 A=2 ,B=- ... 15.61% 667.2K 0.00% 1 A=1 ,B=- ... 0.16% 6.9K 0.81% 575 A=1 ,B=- ... 0.16% 6.8K 1.38% 977 A=2 ,B=- ... 0.16% 6.8K 0.04% 28 A=2 ,B=1 ... 0.15% 6.6K 1.33% 946 A=1 ,B=- ... 0.11% 4.5K 0.06% 46 A=3+,B=- ... 0.10% 4.4K 0.88% 624 A=1 ,B=- ... 0.09% 3.7K 0.74% 524 A=3+,B=1 ... Reviewed-by: Andi Kleen Signed-off-by: Kan Liang Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20240813160208.2493643-7-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Save branch counters for each block

2024-08-14T13:20:40+00:00

When annotating a basic block, it's useful to display the occurrences of other events in the block. The branch counter feature is only available for newer Intel platforms. So a dedicated option to display the branch counters is not introduced. Reuse the existing --total-cycles option, which triggers the annotation of a basic block and displays the cycle-related annotation. When the branch counters information is available, the branch counters are automatically appended after all the cycle-related annotation. Accounting the branch counters as well when accounting the cycles in hist__account_cycles(). In 'struct annotated_branch', introduce a br_cntr array to save the accumulation of each branch counter. In a sample, all the branch counters for a branch are saved in a u64 space. Because the saturation of a branch counter is small, e.g., for Intel Sierra Forest, the saturation is only 3. Add ANNOTATION__BR_CNTR_SATURATED_FLAG to indicate if a branch counter once saturated. That can be used to indicate a potential event lost because of the saturation. Reviewed-by: Andi Kleen Signed-off-by: Kan Liang Acked-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20240813160208.2493643-5-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Cache debuginfo for data type profiling

2024-08-08T12:34:43+00:00

In find_data_type(), it creates and deletes a debug info whenver it tries to find data type for a sample. This is inefficient and it most likely accesses the same binary again and again. Let's add a single entry cache the debug info structure for the last DSO. Depending on sample data, it usually gives me 2~3x (and sometimes more) speed ups. Note that this will introduce a little difference in the output due to the order of checking stack operations. It used to check the stack ops before checking the availability of debug info but I moved it after the symbol check. So it'll report stack operations in DSOs without debug info as unknown. But I think it's ok and better to have the checking near the caching logic. Committer testing: root@x1:~# perf mem record -a sleep 5s root@x1:~# perf evlist cpu_atom/mem-loads,ldlat=30/P cpu_atom/mem-stores/P dummy:u root@x1:~# diff -u before after --- before 2024-08-08 09:33:53.880780784 -0300 +++ after 2024-08-08 09:35:13.917325041 -0300 @@ -81,8 +81,8 @@ # Overhead Data Type # ........ ......... # - 55.43% (unknown) - 11.61% (stack operation) + 55.56% (unknown) + 11.48% (stack operation) 4.93% struct pcpu_hot 3.26% unsigned int 2.48% struct Signed-off-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Athira Rajeev Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240805234648.1453689-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Use annotation__pcnt_width() consistently

2024-08-05T19:11:42+00:00

The annotation__pcnt_width() calculates the screen width for the overhead (percent) area considering event groups properly. Use this function consistently so that we can make sure it has similar output in different modes. But there's a difference in stdio and tui output: stdio uses 8 and tui uses 7 for a percent. Let's use 8 and adjust the print width in __annotation_line__write() properly. Signed-off-by: Namhyung Kim Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240803211332.1107222-4-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

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

2024-07-31T19:12:59+00:00

Currently, the perf tool infrastructure uses the disasm_line__parse function to parse disassembled line. Example snippet from objdump: objdump --start-address=

--stop-address=

-d --no-show-raw-insn -C 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. Reviewed-by: Kajol Jain Reviewed-by: Namhyung Kim Signed-off-by: Athira Rajeev Tested-by: Kajol Jain Cc: Adrian Hunter Cc: Akanksha J N Cc: Christophe Leroy Cc: Disha Goel Cc: Hari Bathini Cc: Ian Rogers Cc: Jiri Olsa Cc: Madhavan Srinivasan Cc: Segher Boessenkool Link: https://lore.kernel.org/lkml/20240718084358.72242-5-atrajeev@linux.vnet.ibm.com [ Add check for strndup() result ] Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Move 'start' field struct to 'struct annotated_source'

2024-04-08T20:43:20+00:00

It's only used in 'perf annotate' output which means functions with actual samples. No need to consume memory for every symbol ('struct annotation'). Signed-off-by: Namhyung Kim Link: https://lore.kernel.org/r/20240404175716.1225482-10-namhyung@kernel.org Cc: Ian Rogers Cc: Peter Zijlstra Cc: Adrian Hunter Cc: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Ingo Molnar Cc: Kan Liang Cc: LKML Cc: Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Move nr_events struct to 'struct annotated_source'

2024-04-08T20:43:20+00:00

It's only used in 'perf annotate' output which means functions with actual samples. No need to consume memory for every symbol ('struct annotation'). Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240404175716.1225482-9-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Move 'max_jump_sources' struct to 'struct annotated_source'

2024-04-08T20:43:20+00:00

It's only used in 'perf annotate' output which means functions with actual samples. No need to consume memory for every symbol ('struct annotation'). Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240404175716.1225482-8-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Move 'widths' struct to 'struct annotated_source'

2024-04-08T20:43:20+00:00

It's only used in 'perf annotate' output which means functions with actual samples. No need to consume memory for every symbol ('struct annotation'). Also move the 'max_line_len' field into it as it's related. Signed-off-by: Namhyung Kim Cc: Adrian Hunter Cc: Ian Rogers Cc: Ingo Molnar Cc: Jiri Olsa Cc: Kan Liang Cc: Peter Zijlstra Link: https://lore.kernel.org/r/20240404175716.1225482-7-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo