Em Wed, May 27, 2020 at 11:20:57AM -0300, Arnaldo Carvalho de Melo escreveu: > Em Mon, Apr 27, 2020 at 02:15:16PM +0800, Nick Gasson escreveu: > > For a Java method signature like: > > > > Ljava/lang/AbstractStringBuilder;appendChars(Ljava/lang/String;II)V > > > > The demangler produces: > > > > void class java.lang.AbstractStringBuilder.appendChars(class > > java.lang., shorttring., int, int) > > > > The arguments should be (java.lang.String, int, int) but the demangler > > interprets the "S" in String as the type code for "short". Correct this > > and two other minor things: > > > > - There is no "bool" type in Java, should be "boolean". > > > > - The demangler prepends "class" to every Java class name. This is not > > standard Java syntax and it wastes a lot of horizontal space if the > > signature is long. Remove this as there isn't any ambiguity between > > class names and primitives. > > > > Also added a test case. > > So, I took this and split into a patch for the new 'perf test java' and > then the fix, so that we can see the problem being detected and then > apply the fix and see it fixed, the last patch in this series thus > became:
This is in my tmp.perf/core branch pending a round of testing, after that it'll move to perf/core on its way to 5.8, thanks. - Arnaldo > > commit 341e11c1d445999932da3f5d626c9fe096949ae3 > Author: Nick Gasson <nick.gas...@arm.com> > Date: Mon Apr 27 14:15:16 2020 +0800 > > perf jvmti: Fix demangling Java symbols > > For a Java method signature like: > > Ljava/lang/AbstractStringBuilder;appendChars(Ljava/lang/String;II)V > > The demangler produces: > > void class java.lang.AbstractStringBuilder.appendChars(class > java.lang., shorttring., int, int) > > The arguments should be (java.lang.String, int, int) but the demangler > interprets the "S" in String as the type code for "short". Correct this > and two other minor things: > > - There is no "bool" type in Java, should be "boolean". > > - The demangler prepends "class" to every Java class name. This is not > standard Java syntax and it wastes a lot of horizontal space if the > signature is long. Remove this as there isn't any ambiguity between > class names and primitives. > > Committer notes: > > This was split from a larger patch that also added a java demangler > 'perf test' entry, that, before this patch shows the error being fixed > by it: > > $ perf test java > 65: Demangle Java : FAILED! > $ perf test -v java > Couldn't bump rlimit(MEMLOCK), failures may take place when creating > BPF maps, etc > 65: Demangle Java : > --- start --- > test child forked, pid 307264 > FAILED: Ljava/lang/StringLatin1;equals([B[B)Z: bool class > java.lang.StringLatin1.equals(byte[], byte[]) != boolean > java.lang.StringLatin1.equals(byte[], byte[]) > FAILED: Ljava/util/zip/ZipUtils;CENSIZ([BI)J: long class > java.util.zip.ZipUtils.CENSIZ(byte[], int) != long > java.util.zip.ZipUtils.CENSIZ(byte[], int) > FAILED: > Ljava/util/regex/Pattern$BmpCharProperty;match(Ljava/util/regex/Matcher;ILjava/lang/CharSequence;)Z: > bool class java.util.regex.Pattern$BmpCharProperty.match(class > java.util.regex.Matcher., int, class java.lang., charhar, shortequence) != > boolean > java.util.regex.Pattern$BmpCharProperty.match(java.util.regex.Matcher, int, > java.lang.CharSequence) > FAILED: > Ljava/lang/AbstractStringBuilder;appendChars(Ljava/lang/String;II)V: void > class java.lang.AbstractStringBuilder.appendChars(class java.lang., > shorttring., int, int) != void > java.lang.AbstractStringBuilder.appendChars(java.lang.String, int, int) > FAILED: Ljava/lang/Object;<init>()V: void class > java.lang.Object<init>() != void java.lang.Object<init>() > test child finished with -1 > ---- end ---- > Demangle Java: FAILED! > $ > > After applying this patch: > > $ perf test java > 65: Demangle Java : Ok > $ > > Signed-off-by: Nick Gasson <nick.gas...@arm.com> > Reviewed-by: Ian Rogers <irog...@google.com> > Tested-by: Arnaldo Carvalho de Melo <a...@redhat.com> > Tested-by: Ian Rogers <irog...@google.com> > Cc: Alexander Shishkin <alexander.shish...@linux.intel.com> > Cc: Jiri Olsa <jo...@redhat.com> > Cc: Mark Rutland <mark.rutl...@arm.com> > Cc: Namhyung Kim <namhy...@kernel.org> > Cc: Peter Zijlstra <pet...@infradead.org> > Link: > http://lore.kernel.org/lkml/20200427061520.24905-4-nick.gas...@arm.com > Signed-off-by: Arnaldo Carvalho de Melo <a...@redhat.com> > > diff --git a/tools/perf/util/demangle-java.c b/tools/perf/util/demangle-java.c > index 6fb7f34c0814..39c05200ed65 100644 > --- a/tools/perf/util/demangle-java.c > +++ b/tools/perf/util/demangle-java.c > @@ -15,7 +15,7 @@ enum { > MODE_CLASS = 1, > MODE_FUNC = 2, > MODE_TYPE = 3, > - MODE_CTYPE = 3, /* class arg */ > + MODE_CTYPE = 4, /* class arg */ > }; > > #define BASE_ENT(c, n) [c - 'A']=n > @@ -27,7 +27,7 @@ static const char *base_types['Z' - 'A' + 1] = { > BASE_ENT('I', "int" ), > BASE_ENT('J', "long" ), > BASE_ENT('S', "short" ), > - BASE_ENT('Z', "bool" ), > + BASE_ENT('Z', "boolean" ), > }; > > /* > @@ -59,15 +59,16 @@ __demangle_java_sym(const char *str, const char *end, > char *buf, int maxlen, int > > switch (*q) { > case 'L': > - if (mode == MODE_PREFIX || mode == MODE_CTYPE) { > - if (mode == MODE_CTYPE) { > + if (mode == MODE_PREFIX || mode == MODE_TYPE) { > + if (mode == MODE_TYPE) { > if (narg) > rlen += scnprintf(buf + rlen, > maxlen - rlen, ", "); > narg++; > } > - rlen += scnprintf(buf + rlen, maxlen - rlen, > "class "); > if (mode == MODE_PREFIX) > mode = MODE_CLASS; > + else > + mode = MODE_CTYPE; > } else > buf[rlen++] = *q; > break; > @@ -120,7 +121,7 @@ __demangle_java_sym(const char *str, const char *end, > char *buf, int maxlen, int > if (mode != MODE_CLASS && mode != MODE_CTYPE) > goto error; > /* safe because at least one other char to process */ > - if (isalpha(*(q + 1))) > + if (isalpha(*(q + 1)) && mode == MODE_CLASS) > rlen += scnprintf(buf + rlen, maxlen - rlen, > "."); > if (mode == MODE_CLASS) > mode = MODE_FUNC; -- - Arnaldo
