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

perf annotate: Fix hashmap__new() error checking

2026-03-25T10:08:29+00:00

[ Upstream commit bf29cb3641b80bac759c3332b02e0b270e16bf94 ] The hashmap__new() function never returns NULL, it returns error pointers. Fix the error checking to match. Additionally, set src->samples to NULL to prevent any later code from accidentally using the error pointer. Fixes: d3e7cad6f36d9e80 ("perf annotate: Add a hashmap for symbol histogram") Reviewed-by: Ian Rogers Signed-off-by: Chen Ni Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Tianyou Li Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf annotate: Check return value of evsel__get_arch() properly

2025-12-18T12:54:45+00:00

[ Upstream commit f1204e5846d22fb2fffbd1164eeb19535f306797 ] Check the error code of evsel__get_arch() in the symbol__annotate(). Previously it checked non-zero value but after the refactoring it does only for negative values. Fixes: 0669729eb0afb0cf ("perf annotate: Factor out evsel__get_arch()") Suggested-by: James Clark Acked-by: Namhyung Kim Signed-off-by: Tianyou Li Signed-off-by: Namhyung Kim Signed-off-by: Sasha Levin

perf env: Find correct branch counter info on hybrid

2024-09-11T16:08:46+00:00

No event is printed in the "Branch Counter" column on hybrid machines. For example, $ perf record -e "{cpu_core/branch-instructions/pp,cpu_core/branches/}:S" -j any,counter $ perf report --total-cycles # Branch counter abbr list: # cpu_core/branch-instructions/pp = A # cpu_core/branches/ = B # '-' No event occurs # '+' Event occurrences may be lost due to branch counter saturated # # Sampled Cycles% Sampled Cycles Avg Cycles% Avg Cycles Branch Counter # ............... .............. ........... .......... .............. 44.54% 727.1K 0.00% 1 |+ |+ | 36.31% 592.7K 0.00% 2 |+ |+ | 17.83% 291.1K 0.00% 1 |+ |+ | The branch counter information (br_cntr_width and br_cntr_nr) in the perf_env is retrieved from the CPU_PMU_CAPS. However, the CPU_PMU_CAPS is not available on hybrid machines. Without the width information, the number of occurrences of an event cannot be calculated. For a hybrid machine, the caps information should be retrieved from the PMU_CAPS, and stored in the perf_env->pmu_caps. Add a perf_env__find_br_cntr_info() to return the correct branch counter information from the corresponding fields. Committer notes: While testing I couldn't s ee those "Branch counter" columns enabled by pressing 'B' on the TUI, after reporting it to the list Kan explained the situation: For a hybrid client, the "Branch Counter" feature is only supported starting from the just released Lunar Lake. Perf falls back to only "ANY" on your Raptor Lake. The "The branch counter is not available" message is expected. Here is the 'perf evlist' result from my Lunar Lake machine, # perf evlist -v cpu_core/branch-instructions/pp: type: 4 (cpu_core), size: 136, config: 0xc4 (branch-instructions), { sample_period, sample_freq }: 4000, sample_type: IP|TID|TIME|READ|PERIOD|BRANCH_STACK|IDENTIFIER, read_format: ID|GROUP|LOST, disabled: 1, freq: 1, enable_on_exec: 1, precise_ip: 2, sample_id_all: 1, exclude_guest: 1, branch_sample_type: ANY|COUNTERS # Fixes: 6f9d8d1de2c61288 ("perf script: Add branch counters") Reviewed-by: Ian Rogers Signed-off-by: Kan Liang Cc: Adrian Hunter Cc: Jiri Olsa Cc: Kan Liang Cc: Namhyung Kim Link: https://lore.kernel.org/r/20240909184201.553519-1-kan.liang@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Treat 'call' instruction as stack operation

2024-09-10T20:32:47+00:00

I found some portion of mem-store events sampled on CALL instruction which has no memory access. But it actually saves a return address into stack. It should be considered as a stack operation like RET instruction. 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/20240909214251.3033827-1-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

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: Add --skip-empty option

2024-08-05T19:14:01+00:00

Like in 'perf report', we want to hide empty events in the 'perf annotate' output. This is consistent when the option is set in perf report. For example, the following command would use 3 events including dummy. $ perf mem record -a -- perf test -w noploop $ perf evlist cpu/mem-loads,ldlat=30/P cpu/mem-stores/P dummy:u Just using perf annotate with --group will show the all 3 events. $ perf annotate --group --stdio | head Percent | Source code & Disassembly of ... -------------------------------------------------------------- : 0 0xe060 <_dl_relocate_object>: 0.00 0.00 0.00 : e060: pushq %rbp 0.00 0.00 0.00 : e061: movq %rsp, %rbp 0.00 0.00 0.00 : e064: pushq %r15 0.00 0.00 0.00 : e066: movq %rdi, %r15 0.00 0.00 0.00 : e069: pushq %r14 0.00 0.00 0.00 : e06b: pushq %r13 0.00 0.00 0.00 : e06d: movl %edx, %r13d Now with --skip-empty, it'll hide the last dummy event. $ perf annotate --group --stdio --skip-empty | head Percent | Source code & Disassembly of ... ------------------------------------------------------ : 0 0xe060 <_dl_relocate_object>: 0.00 0.00 : e060: pushq %rbp 0.00 0.00 : e061: movq %rsp, %rbp 0.00 0.00 : e064: pushq %r15 0.00 0.00 : e066: movq %rdi, %r15 0.00 0.00 : e069: pushq %r14 0.00 0.00 : e06b: pushq %r13 0.00 0.00 : e06d: movl %edx, %r13d Committer testing: root@x1:~# perf evlist cpu_atom/mem-loads,ldlat=30/P cpu_atom/mem-stores/P dummy:u root@x1:~# Before: root@x1:~# perf annotate --group --stdio2 do_lookup_x | head -25 Samples: 20 of events 'cpu_atom/mem-loads,ldlat=30/P, cpu_atom/mem-stores/P, dummy:u', 4000 Hz, Event count (approx.): 769079, [percent: local period] do_lookup_x() /usr/lib64/ld-linux-x86-64.so.2 Percent 0x9900 : pushq %rbp movq %rsp,%rbp pushq %r15 pushq %r14 pushq %r13 pushq %r12 pushq %rbx subq $0x88,%rsp movq %rdi,-0x50(%rbp) movl 8(%r9),%edi movq 0x10(%rbp),%r12 movq 0x28(%rbp),%r10 movq %rdx,-0x70(%rbp) movq %rcx,-0x58(%rbp) movq %rdi,%r11 0.00 5.73 0.00 movq %r8,-0x68(%rbp) movq (%r9),%r8 movl %esi,%eax 8.30 0.00 0.00 movl 0x30(%rbp),%r9d movl %esi,%r15d shrl $6, %eax movq %r8,%r13 root@x1:~# After: root@x1:~# perf annotate --group --skip-empty --stdio2 do_lookup_x | head -25 Samples: 20 of events 'cpu_atom/mem-loads,ldlat=30/P, cpu_atom/mem-stores/P', 4000 Hz, Event count (approx.): 769079, [percent: local period] do_lookup_x() /usr/lib64/ld-linux-x86-64.so.2 Percent 0x9900 : pushq %rbp movq %rsp,%rbp pushq %r15 pushq %r14 pushq %r13 pushq %r12 pushq %rbx subq $0x88,%rsp movq %rdi,-0x50(%rbp) movl 8(%r9),%edi movq 0x10(%rbp),%r12 movq 0x28(%rbp),%r10 movq %rdx,-0x70(%rbp) movq %rcx,-0x58(%rbp) movq %rdi,%r11 0.00 5.73 movq %r8,-0x68(%rbp) movq (%r9),%r8 movl %esi,%eax 8.30 0.00 movl 0x30(%rbp),%r9d movl %esi,%r15d shrl $6, %eax movq %r8,%r13 root@x1:~# 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/20240803211332.1107222-6-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