user/sven/linux.git/tools/perf, branch v4.19.92

perf probe: Fix to show function entry line as probe-able

2019-12-31T15:36:37Z

commit 91e2f539eeda26ab00bd03fae8dc434c128c85ed upstream. Fix die_walk_lines() to list the function entry line correctly. Since the dwarf_entrypc() does not return the entry pc if the DIE has only range attribute, __die_walk_funclines() fails to list the declaration line (entry line) in that case. To solve this issue, this introduces die_entrypc() which correctly returns the entry PC (the first address range) even if the DIE has only range attribute. With this fix die_walk_lines() shows the function entry line is able to probe correctly. Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface") Signed-off-by: Masami Hiramatsu Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157190837419.1859.4619125803596816752.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Cc: Thomas Backlund Signed-off-by: Greg Kroah-Hartman

perf probe: Filter out instances except for inlined subroutine and subprogram

2019-12-31T15:35:53Z

[ Upstream commit da6cb952a89efe24bb76c4971370d485737a2d85 ] Filter out instances except for inlined_subroutine and subprogram DIE in die_walk_instances() and die_is_func_instance(). This fixes an issue that perf probe sets some probes on calling address instead of a target function itself. When perf probe walks on instances of an abstruct origin (a kind of function prototype of inlined function), die_walk_instances() can also pass a GNU_call_site (a GNU extension for call site) to callback. Since it is not an inlined instance of target function, we have to filter out when searching a probe point. Without this patch, perf probe sets probes on call site address too.This can happen on some function which is marked "inlined", but has actual symbol. (I'm not sure why GCC mark it "inlined"): # perf probe -D vfs_read p:probe/vfs_read _text+2500017 p:probe/vfs_read_1 _text+2499468 p:probe/vfs_read_2 _text+2499563 p:probe/vfs_read_3 _text+2498876 p:probe/vfs_read_4 _text+2498512 p:probe/vfs_read_5 _text+2498627 With this patch: Slightly different results, similar tho: # perf probe -D vfs_read p:probe/vfs_read _text+2498512 Committer testing: # uname -a Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux Before: # perf probe -D vfs_read p:probe/vfs_read _text+3131557 p:probe/vfs_read_1 _text+3130975 p:probe/vfs_read_2 _text+3131047 p:probe/vfs_read_3 _text+3130380 p:probe/vfs_read_4 _text+3130000 # uname -a Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux # After: # perf probe -D vfs_read p:probe/vfs_read _text+3130000 # Fixes: db0d2c6420ee ("perf probe: Search concrete out-of-line instances") Signed-off-by: Masami Hiramatsu Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157241937063.32002.11024544873990816590.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf probe: Skip end-of-sequence and non statement lines

2019-12-31T15:35:53Z

[ Upstream commit f4d99bdfd124823a81878b44b5e8750b97f73902 ] Skip end-of-sequence and non-statement lines while walking through lines list. The "end-of-sequence" line information means: "the current address is that of the first byte after the end of a sequence of target machine instructions." (DWARF version 4 spec 6.2.2) This actually means out of scope and we can not probe on it. On the other hand, the statement lines (is_stmt) means: "the current instruction is a recommended breakpoint location. A recommended breakpoint location is intended to “represent” a line, a statement and/or a semantically distinct subpart of a statement." (DWARF version 4 spec 6.2.2) So, non-statement line info also should be skipped. These can reduce unneeded probe points and also avoid an error. E.g. without this patch: # perf probe -a "clear_tasks_mm_cpumask:1" Added new events: probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1) probe:clear_tasks_mm_cpumask_1 (on clear_tasks_mm_cpumask:1) probe:clear_tasks_mm_cpumask_2 (on clear_tasks_mm_cpumask:1) probe:clear_tasks_mm_cpumask_3 (on clear_tasks_mm_cpumask:1) probe:clear_tasks_mm_cpumask_4 (on clear_tasks_mm_cpumask:1) You can now use it in all perf tools, such as: perf record -e probe:clear_tasks_mm_cpumask_4 -aR sleep 1 # This puts 5 probes on one line, but acutally it's not inlined function. This is because there are many non statement instructions at the function prologue. With this patch: # perf probe -a "clear_tasks_mm_cpumask:1" Added new event: probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1) You can now use it in all perf tools, such as: perf record -e probe:clear_tasks_mm_cpumask -aR sleep 1 # Now perf-probe skips unneeded addresses. Committer testing: Slightly different results, but similar: Before: # uname -a Linux quaco 5.3.8-200.fc30.x86_64 #1 SMP Tue Oct 29 14:46:22 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux # # perf probe -a "clear_tasks_mm_cpumask:1" Added new events: probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1) probe:clear_tasks_mm_cpumask_1 (on clear_tasks_mm_cpumask:1) probe:clear_tasks_mm_cpumask_2 (on clear_tasks_mm_cpumask:1) You can now use it in all perf tools, such as: perf record -e probe:clear_tasks_mm_cpumask_2 -aR sleep 1 # After: # perf probe -a "clear_tasks_mm_cpumask:1" Added new event: probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask:1) You can now use it in all perf tools, such as: perf record -e probe:clear_tasks_mm_cpumask -aR sleep 1 # perf probe -l probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask@kernel/cpu.c) # Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface") Signed-off-by: Masami Hiramatsu Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157241936090.32002.12156347518596111660.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf probe: Fix to show calling lines of inlined functions

2019-12-31T15:35:52Z

[ Upstream commit 86c0bf8539e7f46d91bd105e55eda96e0064caef ] Fix to show calling lines of inlined functions (where an inline function is called). die_walk_lines() filtered out the lines inside inlined functions based on the address. However this also filtered out the lines which call those inlined functions from the target function. To solve this issue, check the call_file and call_line attributes and do not filter out if it matches to the line information. Without this fix, perf probe -L doesn't show some lines correctly. (don't see the lines after 17) # perf probe -L vfs_read 0 ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) 1 { 2 ssize_t ret; 4 if (!(file->f_mode & FMODE_READ)) return -EBADF; 6 if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; 8 if (unlikely(!access_ok(buf, count))) return -EFAULT; 11 ret = rw_verify_area(READ, file, pos, count); 12 if (!ret) { 13 if (count > MAX_RW_COUNT) count = MAX_RW_COUNT; 15 ret = __vfs_read(file, buf, count, pos); 16 if (ret > 0) { fsnotify_access(file); add_rchar(current, ret); } With this fix: # perf probe -L vfs_read 0 ssize_t vfs_read(struct file *file, char __user *buf, size_t count, loff_t *pos) 1 { 2 ssize_t ret; 4 if (!(file->f_mode & FMODE_READ)) return -EBADF; 6 if (!(file->f_mode & FMODE_CAN_READ)) return -EINVAL; 8 if (unlikely(!access_ok(buf, count))) return -EFAULT; 11 ret = rw_verify_area(READ, file, pos, count); 12 if (!ret) { 13 if (count > MAX_RW_COUNT) count = MAX_RW_COUNT; 15 ret = __vfs_read(file, buf, count, pos); 16 if (ret > 0) { 17 fsnotify_access(file); 18 add_rchar(current, ret); } 20 inc_syscr(current); } Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface") Signed-off-by: Masami Hiramatsu Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157241937995.32002.17899884017011512577.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf probe: Return a better scope DIE if there is no best scope

2019-12-31T15:35:51Z

[ Upstream commit c701636aeec4c173208697d68da6e4271125564b ] Make find_best_scope() returns innermost DIE at given address if there is no best matched scope DIE. Since Gcc sometimes generates intuitively strange line info which is out of inlined function address range, we need this fixup. Without this, sometimes perf probe failed to probe on a line inside an inlined function: # perf probe -D ksys_open:3 Failed to find scope of probe point. Error: Failed to add events. With this fix, 'perf probe' can probe it: # perf probe -D ksys_open:3 p:probe/ksys_open _text+25707308 p:probe/ksys_open_1 _text+25710596 p:probe/ksys_open_2 _text+25711114 p:probe/ksys_open_3 _text+25711343 p:probe/ksys_open_4 _text+25714058 p:probe/ksys_open_5 _text+2819653 p:probe/ksys_open_6 _text+2819701 Signed-off-by: Masami Hiramatsu Tested-by: Arnaldo Carvalho de Melo Cc: Namhyung Kim Cc: Ravi Bangoria Cc: Steven Rostedt (VMware) Cc: Tom Zanussi Link: http://lore.kernel.org/lkml/157291300887.19771.14936015360963292236.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf probe: Skip overlapped location on searching variables

2019-12-31T15:35:51Z

[ Upstream commit dee36a2abb67c175265d49b9a8c7dfa564463d9a ] Since debuginfo__find_probes() callback function can be called with the location which already passed, the callback function must filter out such overlapped locations. add_probe_trace_event() has already done it by commit 1a375ae7659a ("perf probe: Skip same probe address for a given line"), but add_available_vars() doesn't. Thus perf probe -v shows same address repeatedly as below: # perf probe -V vfs_read:18 Available variables at vfs_read:18 @ char* buf loff_t* pos ssize_t ret struct file* file @ char* buf loff_t* pos ssize_t ret struct file* file @ char* buf loff_t* pos ssize_t ret struct file* file With this fix, perf probe -V shows it correctly: # perf probe -V vfs_read:18 Available variables at vfs_read:18 @ char* buf loff_t* pos ssize_t ret struct file* file @ char* buf loff_t* pos ssize_t ret struct file* file Fixes: cf6eb489e5c0 ("perf probe: Show accessible local variables") Signed-off-by: Masami Hiramatsu Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157241938927.32002.4026859017790562751.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf parse: If pmu configuration fails free terms

2019-12-31T15:35:50Z

[ Upstream commit 38f2c4226e6bc3e8c41c318242821ba5dc825aba ] Avoid a memory leak when the configuration fails. Signed-off-by: Ian Rogers Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexei Starovoitov Cc: Andi Kleen Cc: Daniel Borkmann Cc: Jin Yao Cc: John Garry Cc: Kan Liang Cc: Mark Rutland Cc: Martin KaFai Lau Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Song Liu Cc: Stephane Eranian Cc: Yonghong Song Cc: bpf@vger.kernel.org Cc: clang-built-linux@googlegroups.com Cc: netdev@vger.kernel.org Link: http://lore.kernel.org/lkml/20191030223448.12930-9-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf tools: Splice events onto evlist even on error

2019-12-31T15:35:48Z

[ Upstream commit 8e8714c3d157568b7a769917a5e05573bbaf5af0 ] If event parsing fails the event list is leaked, instead splice the list onto the out result and let the caller cleanup. An example input for parse_events found by libFuzzer that reproduces this memory leak is 'm{'. Signed-off-by: Ian Rogers Acked-by: Jiri Olsa Cc: Adrian Hunter Cc: Alexander Shishkin Cc: Alexei Starovoitov Cc: Andi Kleen Cc: Daniel Borkmann Cc: Jin Yao Cc: John Garry Cc: Kan Liang Cc: Mark Rutland Cc: Martin KaFai Lau Cc: Namhyung Kim Cc: Peter Zijlstra Cc: Song Liu Cc: Stephane Eranian Cc: Yonghong Song Cc: bpf@vger.kernel.org Cc: clang-built-linux@googlegroups.com Cc: netdev@vger.kernel.org Link: http://lore.kernel.org/lkml/20191025180827.191916-5-irogers@google.com Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf probe: Fix to probe a function which has no entry pc

2019-12-31T15:35:47Z

[ Upstream commit 5d16dbcc311d91267ddb45c6da4f187be320ecee ] Fix 'perf probe' to probe a function which has no entry pc or low pc but only has ranges attribute. probe_point_search_cb() uses dwarf_entrypc() to get the probe address, but that doesn't work for the function DIE which has only ranges attribute. Use die_entrypc() instead. Without this fix: # perf probe -k ../build-x86_64/vmlinux -D clear_tasks_mm_cpumask:0 Probe point 'clear_tasks_mm_cpumask' not found. Error: Failed to add events. With this: # perf probe -k ../build-x86_64/vmlinux -D clear_tasks_mm_cpumask:0 p:probe/clear_tasks_mm_cpumask clear_tasks_mm_cpumask+0 Committer testing: Before: [root@quaco ~]# perf probe clear_tasks_mm_cpumask:0 Probe point 'clear_tasks_mm_cpumask' not found. Error: Failed to add events. [root@quaco ~]# After: [root@quaco ~]# perf probe clear_tasks_mm_cpumask:0 Added new event: probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask) You can now use it in all perf tools, such as: perf record -e probe:clear_tasks_mm_cpumask -aR sleep 1 [root@quaco ~]# Using it with 'perf trace': [root@quaco ~]# perf trace -e probe:clear_tasks_mm_cpumask Doesn't seem to be used in x86_64: $ find . -name "*.c" | xargs grep clear_tasks_mm_cpumask ./kernel/cpu.c: * clear_tasks_mm_cpumask - Safely clear tasks' mm_cpumask for a CPU ./kernel/cpu.c:void clear_tasks_mm_cpumask(int cpu) ./arch/xtensa/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/csky/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/sh/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/arm/kernel/smp.c: clear_tasks_mm_cpumask(cpu); ./arch/powerpc/mm/nohash/mmu_context.c: clear_tasks_mm_cpumask(cpu); $ find . -name "*.h" | xargs grep clear_tasks_mm_cpumask ./include/linux/cpu.h:void clear_tasks_mm_cpumask(int cpu); $ find . -name "*.S" | xargs grep clear_tasks_mm_cpumask $ Fixes: e1ecbbc3fa83 ("perf probe: Fix to handle optimized not-inlined functions") Reported-by: Arnaldo Carvalho de Melo Tested-by: Arnaldo Carvalho de Melo Signed-off-by: Masami Hiramatsu Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157199319438.8075.4695576954550638618.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin

perf probe: Fix to show inlined function callsite without entry_pc

2019-12-31T15:35:46Z

[ Upstream commit 18e21eb671dc87a4f0546ba505a89ea93598a634 ] Fix 'perf probe --line' option to show inlined function callsite lines even if the function DIE has only ranges. Without this: # perf probe -L amd_put_event_constraints ... 2 { 3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)) __amd_put_nb_event_constraints(cpuc, event); 5 } With this patch: # perf probe -L amd_put_event_constraints ... 2 { 3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)) 4 __amd_put_nb_event_constraints(cpuc, event); 5 } Committer testing: Before: [root@quaco ~]# perf probe -L amd_put_event_constraints 0 static void amd_put_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) 2 { 3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)) __amd_put_nb_event_constraints(cpuc, event); 5 } PMU_FORMAT_ATTR(event, "config:0-7,32-35"); PMU_FORMAT_ATTR(umask, "config:8-15" ); [root@quaco ~]# After: [root@quaco ~]# perf probe -L amd_put_event_constraints 0 static void amd_put_event_constraints(struct cpu_hw_events *cpuc, struct perf_event *event) 2 { 3 if (amd_has_nb(cpuc) && amd_is_nb_event(&event->hw)) 4 __amd_put_nb_event_constraints(cpuc, event); 5 } PMU_FORMAT_ATTR(event, "config:0-7,32-35"); PMU_FORMAT_ATTR(umask, "config:8-15" ); [root@quaco ~]# perf probe amd_put_event_constraints:4 Added new event: probe:amd_put_event_constraints (on amd_put_event_constraints:4) You can now use it in all perf tools, such as: perf record -e probe:amd_put_event_constraints -aR sleep 1 [root@quaco ~]# [root@quaco ~]# perf probe -l probe:amd_put_event_constraints (on amd_put_event_constraints:4@arch/x86/events/amd/core.c) probe:clear_tasks_mm_cpumask (on clear_tasks_mm_cpumask@kernel/cpu.c) [root@quaco ~]# Using it: [root@quaco ~]# perf trace -e probe:* ^C[root@quaco ~]# Ok, Intel system here... :-) Fixes: 4cc9cec636e7 ("perf probe: Introduce lines walker interface") Signed-off-by: Masami Hiramatsu Tested-by: Arnaldo Carvalho de Melo Cc: Jiri Olsa Cc: Namhyung Kim Link: http://lore.kernel.org/lkml/157199322107.8075.12659099000567865708.stgit@devnote2 Signed-off-by: Arnaldo Carvalho de Melo Signed-off-by: Sasha Levin