linux/tools/perf, branch v3.19

perf probe: Fix probing kretprobes

2015-01-21T13:06:24Z

The commit dfef99cd0b2c ("perf probe: Use ref_reloc_sym based address instead of the symbol name") converts kprobes to use ref_reloc_sym (i.e. _stext) and offset instead of using symbol's name directly. So on my system, adding do_fork ends up with like below: $ sudo perf probe -v --add do_fork%return probe-definition(0): do_fork%return symbol:do_fork file:(null) line:0 offset:0 return:1 lazy:(null) 0 arguments Looking at the vmlinux_path (7 entries long) Using /lib/modules/3.17.6-1-ARCH/build/vmlinux for symbols Could not open debuginfo. Try to use symbols. Opening /sys/kernel/debug/tracing/kprobe_events write=1 Added new event: Writing event: r:probe/do_fork _stext+456136 Failed to write event: Invalid argument Error: Failed to add events. Reason: Operation not permitted (Code: -1) As you can see, the do_fork was translated to _stext+456136. This was because to support (local) symbols that have same name. But the problem is that kretprobe requires to be inserted at function start point so it simply checks whether it's called with offset 0. And if not, it'll return with -EINVAL. You can see it with dmesg. $ dmesg | tail -1 [125621.764103] Return probe must be used without offset. So we need to use the symbol name instead of ref_reloc_sym in case of return probes. Reported-by: Jiri Olsa Signed-off-by: Namhyung Kim Tested-by: Jiri Olsa Acked-by: Masami Hiramatsu Cc: David Ahern Link: http://lkml.kernel.org/r/1421234288-22758-4-git-send-email-namhyung@kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Introduce 'for' method to iterate over the symbols with a given name

2015-01-21T13:06:15Z

Removing boilerplate from two places, where one would have to find the first entry, then iterate using symbol__next_by_name + strcmp to see if the next member had the same name. Cc: David Ahern Cc: Jiri Olsa Cc: Masami Hiramatsu Link: http://lkml.kernel.org/n/tip-eh73z8gthv20yowirmx2yk38@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf probe: Do not rely on map__load() filter to find symbols

2015-01-21T13:06:02Z

The find_probe_trace_events_from_map() searches matching symbol from a map (so from a backing dso). For uprobes, it'll create a new map (and dso) and loads it using a filter. It's a little bit inefficient in that it'll read out the symbol table everytime but works well anyway. For kprobes however, it'll reuse existing kernel map which might be loaded before. In this case map__load() just returns with no result. It makes kprobes always failed to find symbol even if it exists in the map (dso). To fix it, use map__find_symbol_by_name() instead. It'll load a map with full symbols and sorts them by name. It needs to search sibing nodes since there can be multiple (local) symbols with same name. Signed-off-by: Namhyung Kim Cc: David Ahern Cc: Jiri Olsa Cc: Masami Hiramatsu Link: http://lkml.kernel.org/r/1421234288-22758-3-git-send-email-namhyung@kernel.org [ Use symbol__next_by_name ] Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Introduce method to iterate symbols ordered by name

2015-01-21T13:05:54Z

Given a symbol, go to the next entry in a rbtree sorted by symbol name. Cc: David Ahern Cc: Jiri Olsa Cc: Masami Hiramatsu Link: http://lkml.kernel.org/n/tip-aq210drxprnu2so4dye5xa3j@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf symbols: Return the first entry with a given name in find_by_name method

2015-01-21T13:05:44Z

When a dso contains multiple symbols which have same name, current dso__find_symbol_by_name() only finds an one of them and there's no way to get the all symbols without going through the rbtree. So make symbols__find_by_name() return the first entry with the given name and the next patch in this series will provide a way to iterate from there, by the name ordered rb_tree, till a suitable symbol is found. Signed-off-by: Namhyung Kim Cc: David Ahern Cc: Jiri Olsa Cc: Masami Hiramatsu Link: http://lkml.kernel.org/r/1421234288-22758-2-git-send-email-namhyung@kernel.org [ Yanked this independent hunk, without changes, from a larger patch ] Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Fix memory leaks in LOCK handling

2015-01-21T13:05:32Z

The lock prefix handling fails to free the strdup()'d name as well as the fields allocated by the instruction parsing. Signed-off-by: Rabin Vincent Cc: Paul Mackerras Link: http://lkml.kernel.org/r/1421607621-15005-2-git-send-email-rabin@rab.in Signed-off-by: Arnaldo Carvalho de Melo

perf annotate: Handle ins parsing failures

2015-01-21T13:05:17Z

Don't use the ins's ->sncprintf() if the parsing failed. For example, this fixes the display of "imul %edx". Without this patch: | imul (null),(null) After this patch: | imul %edx Signed-off-by: Rabin Vincent Cc: Paul Mackerras Cc: Peter Zijlstra Link: http://lkml.kernel.org/r/1421607621-15005-1-git-send-email-rabin@rab.in Signed-off-by: Arnaldo Carvalho de Melo

perf scripting perl: Force to use stdbool

2015-01-21T13:05:00Z

When building perf for arm64 I hit a warning (and be treated as an error) like below: aarch64-oe-linux-gcc -o .../scripts/perl/Perf-Trace-Util/Context.o -c -Wbad-function-cast \ ... scripts/perl/Perf-Trace-Util/Context.c In file included from .../usr/lib64/perl/5.14.3/CORE/perl.h:2464:0, from Context.xs:23: /.../usr/lib64/perl/5.14.3/CORE/handy.h:108:0: error: "bool" redefined [-Werror] # define bool char ^ In file included from /.../usr/src/kernel/tools/include/linux/types.h:4:0, from /.../usr/src/kernel/arch/arm64/include/uapi/asm/sigcontext.h:19, from /.../usr/include/bits/sigcontext.h:27, from /.../usr/include/signal.h:340, from /.../usr/include/sys/param.h:28, from /.../usr/lib64/perl/5.14.3/CORE/perl.h:678, from Context.xs:23: /.../usr/lib/aarch64-oe-linux/gcc/aarch64-oe-linux/4.9.2/include/stdbool.h:33:0: note: this is the location of the previous definition #define bool _Bool Looks like the failure is caused by arm64 uapi/asm/sigcontext.h, which includes linux/types.h while other archs not. Current perl consider this problem: http://perl5.git.perl.org/perl.git/commit/bd31be4baa3ee68abdb92c0db3200efe0fad903b However there are users which use old version of perl. This patch includes stdbool.h before Context.xs and define HAS_BOOL to prevent perl'e headers define its own 'bool'. Code is learn from perl's git tree. Signed-off-by: Wang Nan Acked-by: Jiri Olsa Acked-by: Namhyung Kim Cc: Li Zefan Link: http://lkml.kernel.org/r/1421671397-4659-1-git-send-email-wangnan0@huawei.com Signed-off-by: Arnaldo Carvalho de Melo

perf evlist: Remove extraneous 'was' on error message

2015-01-21T13:04:15Z

[acme@mica ~]$ trace -p 3330 Error: Unable to find debugfs Hint: Was your kernel was compiled with debugfs support? ^^^ ^^^ Hint: Is the debugfs filesystem mounted? Hint: Try 'sudo mount -t debugfs nodev /sys/kernel/debug' Fix it. Cc: Adrian Hunter Cc: Borislav Petkov Cc: David Ahern Cc: Don Zickus Cc: Frederic Weisbecker Cc: Jiri Olsa Cc: Mike Galbraith Cc: Namhyung Kim Cc: Stephane Eranian Link: http://lkml.kernel.org/n/tip-kb9s0xy5z8i51abdu4bgm3rv@git.kernel.org Signed-off-by: Arnaldo Carvalho de Melo

perf tools powerpc: Use dwfl_report_elf() instead of offline.

2015-01-16T20:49:30Z

dwfl_report_offline() works only when libraries are prelinked. Replace dwfl_report_offline() with dwfl_report_elf() so we correctly extract debug info even from libraries that are not prelinked. Reported-by: Jiri Olsa Signed-off-by: Sukadev Bhattiprolu Tested-by: Jiri Olsa Cc: Jiri Olsa Cc: Michael Ellerman Link: http://lkml.kernel.org/r/20150114221045.GA17703@us.ibm.com Signed-off-by: Arnaldo Carvalho de Melo