kernel/linux.git/tools/perf/util/annotate.h, branch v5.19

perf symbols: Factor out annotation init/exit

2021-11-13T21:11:51+00:00

The exit function fixes a memory leak with the src field as detected by leak sanitizer. An example of which is: Indirect leak of 25133184 byte(s) in 207 object(s) allocated from: #0 0x7f199ecfe987 in __interceptor_calloc libsanitizer/asan/asan_malloc_linux.cpp:154 #1 0x55defe638224 in annotated_source__alloc_histograms util/annotate.c:803 #2 0x55defe6397e4 in symbol__hists util/annotate.c:952 #3 0x55defe639908 in symbol__inc_addr_samples util/annotate.c:968 #4 0x55defe63aa29 in hist_entry__inc_addr_samples util/annotate.c:1119 #5 0x55defe499a79 in hist_iter__report_callback tools/perf/builtin-report.c:182 #6 0x55defe7a859d in hist_entry_iter__add util/hist.c:1236 #7 0x55defe49aa63 in process_sample_event tools/perf/builtin-report.c:315 #8 0x55defe731bc8 in evlist__deliver_sample util/session.c:1473 #9 0x55defe731e38 in machines__deliver_event util/session.c:1510 #10 0x55defe732a23 in perf_session__deliver_event util/session.c:1590 #11 0x55defe72951e in ordered_events__deliver_event util/session.c:183 #12 0x55defe740082 in do_flush util/ordered-events.c:244 #13 0x55defe7407cb in __ordered_events__flush util/ordered-events.c:323 #14 0x55defe740a61 in ordered_events__flush util/ordered-events.c:341 #15 0x55defe73837f in __perf_session__process_events util/session.c:2390 #16 0x55defe7385ff in perf_session__process_events util/session.c:2420 ... Signed-off-by: Ian Rogers Acked-by: Namhyung Kim Cc: Alexander Shishkin Cc: Ingo Molnar Cc: James Clark Cc: Jiri Olsa Cc: Kajol Jain Cc: Mark Rutland Cc: Martin Liška Cc: Peter Zijlstra Cc: Stephane Eranian Link: https://lore.kernel.org/r/20211112035124.94327-3-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Show full source location with 'l' hotkey

2021-03-06T19:42:31+00:00

Right now, when Line numbers are displayed, one can't easily find a source file that the line corresponds to. When a source line is selected and 'l' is pressed, full source file location is displayed in perf UI footer line. The hotkey works only for source code lines. Signed-off-by: Martin Liška Tested-by: Arnaldo Carvalho de Melo Link: http://lore.kernel.org/lkml/25a6384f-d862-5dda-4fec-8f0555599c75@suse.cz Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Fix jump parsing for C++ code.

2021-02-11T21:23:53+00:00

Considering the following testcase: int foo(int a, int b) { for (unsigned i = 0; i < 1000000000; i++) a += b; return a; } int main() { foo (3, 4); return 0; } 'perf annotate' displays: 86.52 │40055e: → ja 40056c 13.37 │400560: mov -0x18(%rbp),%eax │400563: add %eax,-0x14(%rbp) │400566: addl $0x1,-0x4(%rbp) 0.11 │40056a: → jmp 400557 │40056c: mov -0x14(%rbp),%eax │40056f: pop %rbp and the 'ja 40056c' does not link to the location in the function. It's caused by fact that comma is wrongly parsed, it's part of function signature. With my patch I see: 86.52 │ ┌──ja 26 13.37 │ │ mov -0x18(%rbp),%eax │ │ add %eax,-0x14(%rbp) │ │ addl $0x1,-0x4(%rbp) 0.11 │ │↑ jmp 11 │26:└─→mov -0x14(%rbp),%eax and 'o' output prints: 86.52 │4005┌── ↓ ja 40056c 13.37 │4005│0: mov -0x18(%rbp),%eax │4005│3: add %eax,-0x14(%rbp) │4005│6: addl $0x1,-0x4(%rbp) 0.11 │4005│a: ↑ jmp 400557 │4005└─→ mov -0x14(%rbp),%eax On the contrary, compiling the very same file with gcc -x c, the parsing is fine because function arguments are not displayed: jmp 400543 Committer testing: Before: $ cat cpp_args_annotate.c int foo(int a, int b) { for (unsigned i = 0; i < 1000000000; i++) a += b; return a; } int main() { foo (3, 4); return 0; } $ gcc --version |& head -1 gcc (GCC) 10.2.1 20201125 (Red Hat 10.2.1-9) $ gcc -g cpp_args_annotate.c -o cpp_args_annotate $ perf record ./cpp_args_annotate [ perf record: Woken up 2 times to write data ] [ perf record: Captured and wrote 0.275 MB perf.data (7188 samples) ] $ perf annotate --stdio2 foo Samples: 7K of event 'cycles:u', 4000 Hz, Event count (approx.): 7468429289, [percent: local period] foo() /home/acme/c/cpp_args_annotate Percent 0000000000401106 : foo(): int foo(int a, int b) { push %rbp mov %rsp,%rbp mov %edi,-0x14(%rbp) mov %esi,-0x18(%rbp) for (unsigned i = 0; i < 1000000000; i++) movl $0x0,-0x4(%rbp) ↓ jmp 1d a += b; 13.45 13: mov -0x18(%rbp),%eax add %eax,-0x14(%rbp) for (unsigned i = 0; i < 1000000000; i++) addl $0x1,-0x4(%rbp) 0.09 1d: cmpl $0x3b9ac9ff,-0x4(%rbp) 86.46 ↑ jbe 13 return a; mov -0x14(%rbp),%eax } pop %rbp ← retq $ I.e. works for C, now lets switch to C++: $ g++ -g cpp_args_annotate.c -o cpp_args_annotate $ perf record ./cpp_args_annotate [ perf record: Woken up 1 times to write data ] [ perf record: Captured and wrote 0.268 MB perf.data (6976 samples) ] $ perf annotate --stdio2 foo Samples: 6K of event 'cycles:u', 4000 Hz, Event count (approx.): 7380681761, [percent: local period] foo() /home/acme/c/cpp_args_annotate Percent 0000000000401106 : foo(int, int): int foo(int a, int b) { push %rbp mov %rsp,%rbp mov %edi,-0x14(%rbp) mov %esi,-0x18(%rbp) for (unsigned i = 0; i < 1000000000; i++) movl $0x0,-0x4(%rbp) cmpl $0x3b9ac9ff,-0x4(%rbp) 86.53 → ja 40112c a += b; 13.32 mov -0x18(%rbp),%eax 0.00 add %eax,-0x14(%rbp) for (unsigned i = 0; i < 1000000000; i++) addl $0x1,-0x4(%rbp) 0.15 → jmp 401117 return a; mov -0x14(%rbp),%eax } pop %rbp ← retq $ Reproduced. Now with this patch: Reusing the C++ built binary, as we can see here: $ readelf -wi cpp_args_annotate | grep producer DW_AT_producer : (indirect string, offset: 0x2e): GNU C++14 10.2.1 20201125 (Red Hat 10.2.1-9) -mtune=generic -march=x86-64 -g $ And furthermore: $ file cpp_args_annotate cpp_args_annotate: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, BuildID[sha1]=4fe3cab260204765605ec630d0dc7a7e93c361a9, for GNU/Linux 3.2.0, with debug_info, not stripped $ perf buildid-list -i cpp_args_annotate 4fe3cab260204765605ec630d0dc7a7e93c361a9 $ perf buildid-list | grep cpp_args_annotate 4fe3cab260204765605ec630d0dc7a7e93c361a9 /home/acme/c/cpp_args_annotate $ It now works: $ perf annotate --stdio2 foo Samples: 6K of event 'cycles:u', 4000 Hz, Event count (approx.): 7380681761, [percent: local period] foo() /home/acme/c/cpp_args_annotate Percent 0000000000401106 : foo(int, int): int foo(int a, int b) { push %rbp mov %rsp,%rbp mov %edi,-0x14(%rbp) mov %esi,-0x18(%rbp) for (unsigned i = 0; i < 1000000000; i++) movl $0x0,-0x4(%rbp) 11: cmpl $0x3b9ac9ff,-0x4(%rbp) 86.53 ↓ ja 26 a += b; 13.32 mov -0x18(%rbp),%eax 0.00 add %eax,-0x14(%rbp) for (unsigned i = 0; i < 1000000000; i++) addl $0x1,-0x4(%rbp) 0.15 ↑ jmp 11 return a; 26: mov -0x14(%rbp),%eax } pop %rbp ← retq $ Signed-off-by: Martin Liška Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Slaby Link: http://lore.kernel.org/lkml/13e1a405-edf9-e4c2-4327-a9b454353730@suse.cz Signed-off-by: Arnaldo Carvalho de Melo

perf tools: Replace zero-length array with flexible-array

2020-05-28T13:03:27+00:00

The current codebase makes use of the zero-length array language extension to the C90 standard, but the preferred mechanism to declare variable-length types such as these ones is a flexible array member[1][2], introduced in C99: struct foo { int stuff; struct boo array[]; }; By making use of the mechanism above, we will get a compiler warning in case the flexible array does not occur last in the structure, which will help us prevent some kind of undefined behavior bugs from being inadvertently introduced[3] to the codebase from now on. Also, notice that, dynamic memory allocations won't be affected by this change: "Flexible array members have incomplete type, and so the sizeof operator may not be applied. As a quirk of the original implementation of zero-length arrays, sizeof evaluates to zero."[1] sizeof(flexible-array-member) triggers a warning because flexible array members have incomplete type[1]. There are some instances of code in which the sizeof operator is being incorrectly/erroneously applied to zero-length arrays and the result is zero. Such instances may be hiding some bugs. So, this work (flexible-array member conversions) will also help to get completely rid of those sorts of issues. This issue was found with the help of Coccinelle. [1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html [2] https://github.com/KSPP/linux/issues/21 [3] commit 76497732932f ("cxgb3/l2t: Fix undefined behaviour") Signed-off-by: Gustavo A. R. Silva Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Gustavo A. R. Silva Cc: Ian Rogers Cc: Jiri Olsa Cc: Mark Rutland Cc: Namhyung Kim Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200515172926.GA31976@embeddedor Signed-off-by: Arnaldo Carvalho de Melo

perf report: Support interactive annotation of code without symbols

2020-03-24T12:36:33+00:00

For perf report on stripped binaries it is currently impossible to do annotation. The annotation state is all tied to symbols, but there are either no symbols, or symbols are not covering all the code. We should support the annotation functionality even without symbols. This patch fakes a symbol and the symbol name is the string of address. After that, we just follow current annotation working flow. For example, 1. perf report Overhead Command Shared Object Symbol 20.67% div libc-2.27.so [.] __random_r 17.29% div libc-2.27.so [.] __random 10.59% div div [.] 0x0000000000000628 9.25% div div [.] 0x0000000000000612 6.11% div div [.] 0x0000000000000645 2. Select the line of "10.59% div div [.] 0x0000000000000628" and ENTER. Annotate 0x0000000000000628 Zoom into div thread Zoom into div DSO (use the 'k' hotkey to zoom directly into the kernel) Browse map details Run scripts for samples of symbol [0x0000000000000628] Run scripts for all samples Switch to another data file in PWD Exit 3. Select the "Annotate 0x0000000000000628" and ENTER. Percent│ │ │ │ Disassembly of section .text: │ │ 0000000000000628 <.text+0x68>: │ divsd %xmm4,%xmm0 │ divsd %xmm3,%xmm1 │ movsd (%rsp),%xmm2 │ addsd %xmm1,%xmm0 │ addsd %xmm2,%xmm0 │ movsd %xmm0,(%rsp) Now we can see the dump of object starting from 0x628. v5: --- Remove the hotkey 'a' implementation from this patch. It will be moved to a separate patch. v4: --- 1. Support the hotkey 'a'. When we press 'a' on address, now it supports the annotation. 2. Change the patch title from "Support interactive annotation of code without symbols" to "perf report: Support interactive annotation of code without symbols" v3: --- Keep just the ANNOTATION_DUMMY_LEN, and remove the opts->annotate_dummy_len since it's the "maybe in future we will provide" feature. v2: --- Fix a crash issue when annotating an address in "unknown" object. The steps to reproduce this issue: perf record -e cycles:u ls perf report 75.29% ls ld-2.27.so [.] do_lookup_x 23.64% ls ld-2.27.so [.] __GI___tunables_init 1.04% ls [unknown] [k] 0xffffffff85c01210 0.03% ls ld-2.27.so [.] _start When annotating 0xffffffff85c01210, the crash happens. v2 adds checking for ms->map in add_annotate_opt(). If the object is "unknown", ms->map is NULL. Committer notes: Renamed new_annotate_sym() to symbol__new_unresolved(). Use PRIx64 to fix this issue in some 32-bit arches: ui/browsers/hists.c: In function 'symbol__new_unresolved': ui/browsers/hists.c:2474:38: error: format '%lx' expects argument of type 'long unsigned int', but argument 5 has type 'u64' {aka 'long long unsigned int'} [-Werror=format=] snprintf(name, sizeof(name), "%-#.*lx", BITS_PER_LONG / 4, addr); ~~~~~~^ ~~~~ %-#.*llx Signed-off-by: Jin Yao Tested-by: Arnaldo Carvalho de Melo Tested-by: Ravi Bangoria Acked-by: Jiri Olsa Cc: Alexander Shishkin Cc: Andi Kleen Cc: Kan Liang Cc: Peter Zijlstra Link: http://lore.kernel.org/lkml/20200227043939.4403-3-yao.jin@linux.intel.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Get rid of annotation->nr_jumps

2020-03-04T13:34:10+00:00

The 'nr_jumps' field in 'struct annotation' is not used since it's inception in commit 2402e4a936a0 ("perf annotate browser: Show 'jumpy' functions"). Get rid of it. Signed-off-by: Ravi Bangoria Acked-by: Jiri Olsa Cc: Ian Rogers Cc: Jin Yao Cc: Namhyung Kim Cc: Song Liu Link: http://lore.kernel.org/lkml/20200204045233.474937-7-ravi.bangoria@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Simplify disasm_line allocation and freeing code

2020-02-27T14:07:13+00:00

We are allocating disasm_line object in annotation_line__new() instead of disasm_line__new(). Similarly annotation_line__delete() is actually freeing disasm_line object as well. This complexity is because of privsize. But we don't need privsize anymore so get rid of privsize and simplify disasm_line allocation and freeing code. Signed-off-by: Ravi Bangoria Acked-by: Jiri Olsa Cc: Ian Rogers Cc: Jin Yao Cc: Namhyung Kim Cc: Song Liu Link: http://lore.kernel.org/lkml/20200204045233.474937-3-ravi.bangoria@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Remove privsize from symbol__annotate() args

2020-02-27T14:06:14+00:00

privsize is passed as 0 from all the symbol__annotate() callers. Remove it from argument list. Signed-off-by: Ravi Bangoria Acked-by: Jiri Olsa Cc: Ian Rogers Cc: Jin Yao Cc: Namhyung Kim Cc: Song Liu Link: http://lore.kernel.org/lkml/20200204045233.474937-2-ravi.bangoria@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Make perf config effective

2020-02-27T13:44:59+00:00

perf default config set by user in [annotate] section is totally ignored by annotate code. Fix it. Before: $ ./perf config annotate.hide_src_code=true annotate.show_nr_jumps=true annotate.show_nr_samples=true $ ./perf annotate shash │ unsigned h = 0; │ movl $0x0,-0xc(%rbp) │ while (*s) │ ↓ jmp 44 │ h = 65599 * h + *s++; 11.33 │24: mov -0xc(%rbp),%eax 43.50 │ imul $0x1003f,%eax,%ecx │ mov -0x18(%rbp),%rax After: │ movl $0x0,-0xc(%rbp) │ ↓ jmp 44 1 │1 24: mov -0xc(%rbp),%eax 4 │ imul $0x1003f,%eax,%ecx │ mov -0x18(%rbp),%rax Note that we have removed show_nr_samples and show_total_period from annotation_options because they are not used. Instead of them we use symbol_conf.show_nr_samples and symbol_conf.show_total_period. Committer testing: Using 'perf annotate --stdio2' to use the TUI rendering but emitting the output to stdio: # perf config # # perf config annotate.hide_src_code=true # perf config annotate.hide_src_code=true # # perf config annotate.show_nr_jumps=true # perf config annotate.show_nr_samples=true # perf config annotate.hide_src_code=true annotate.show_nr_jumps=true annotate.show_nr_samples=true # # Before: # perf annotate --stdio2 ObjectInstance::weak_pointer_was_finalized Samples: 1 of event 'cycles', 4000 Hz, Event count (approx.): 830873, [percent: local period] ObjectInstance::weak_pointer_was_finalized() /usr/lib64/libgjs.so.0.0.0 Percent 00000000000609f0 : endbr64 cmpq $0x0,0x20(%rdi) ↓ je 10 xor %eax,%eax ← retq xchg %ax,%ax 100.00 10: push %rbp cmpq $0x0,0x18(%rdi) mov %rdi,%rbp ↓ jne 20 1b: xor %eax,%eax pop %rbp ← retq nop 20: lea 0x18(%rdi),%rdi → callq JS_UpdateWeakPointerAfterGC(JS::Heap /dev/null Samples: 1 of event 'cycles', 4000 Hz, Event count (approx.): 830873, [percent: local period] ObjectInstance::weak_pointer_was_finalized() /usr/lib64/libgjs.so.0.0.0 Samples endbr64 cmpq $0x0,0x20(%rdi) ↓ je 10 xor %eax,%eax ← retq xchg %ax,%ax 1 1 10: push %rbp cmpq $0x0,0x18(%rdi) mov %rdi,%rbp ↓ jne 20 1 1b: xor %eax,%eax pop %rbp ← retq nop 1 20: lea 0x18(%rdi),%rdi → callq JS_UpdateWeakPointerAfterGC(JS::Heap /dev/null Samples: 1 of event 'cycles', 4000 Hz, Event count (approx.): 830873, [percent: local period] ObjectInstance::weak_pointer_was_finalized() /usr/lib64/libgjs.so.0.0.0 Samples endbr64 cmpq $0x0,0x20(%rdi) ↓ je 10 xor %eax,%eax ← retq xchg %ax,%ax 1 10: push %rbp cmpq $0x0,0x18(%rdi) mov %rdi,%rbp ↓ jne 20 1b: xor %eax,%eax pop %rbp ← retq nop 20: lea 0x18(%rdi),%rdi → callq JS_UpdateWeakPointerAfterGC(JS::Heap Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexey Budankov Cc: Changbin Du Cc: Ian Rogers Cc: Jin Yao Cc: Jiri Olsa Cc: Leo Yan Cc: Namhyung Kim Cc: Song Liu Cc: Taeung Song Cc: Thomas Richter Cc: Yisheng Xie Link: http://lore.kernel.org/lkml/20200213064306.160480-6-ravi.bangoria@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Fix --show-total-period for tui/stdio2

2020-02-27T13:44:40+00:00

perf annotate --show-total-period does not really show total period. The reason is we have two separate variables for the same purpose. One is in symbol_conf.show_total_period and another is annotation_options.show_total_period. We save command line option in symbol_conf.show_total_period but uses annotation_option.show_total_period while rendering tui/stdio2 browser. Though, we copy symbol_conf.show_total_period to annotation__default_options.show_total_period but that is not really effective as we don't use annotation__default_options once we copy default options to dynamic variable annotate.opts in cmd_annotate(). Instead of all these complication, keep only one variable and use it all over. symbol_conf.show_total_period is used by perf report/top as well. So let's kill annotation_options.show_total_period. On a side note, I've kept annotation_options.show_total_period definition because it's still used by perf-config code. Follow up patch to fix perf-config for annotate will remove annotation_options.show_total_period. Signed-off-by: Ravi Bangoria Tested-by: Arnaldo Carvalho de Melo Cc: Adrian Hunter Cc: Alexey Budankov Cc: Changbin Du Cc: Ian Rogers Cc: Jin Yao Cc: Jiri Olsa Cc: Leo Yan Cc: Namhyung Kim Cc: Song Liu Cc: Taeung Song Cc: Thomas Richter Cc: Yisheng Xie Link: http://lore.kernel.org/lkml/20200213064306.160480-3-ravi.bangoria@linux.ibm.com Signed-off-by: Arnaldo Carvalho de Melo