Date: Wed, 20 Jul 2011 19:08:35 GMT From: Alex Samorukov <samm@os2.kiev.ua> To: freebsd-gnats-submit@FreeBSD.org Subject: misc/159064: MFC request for dtrace to fix "invalid probe specifier" Message-ID: <201107201908.p6KJ8Z8G059350@red.freebsd.org> Resent-Message-ID: <201107201910.p6KJAAPW014457@freefall.freebsd.org>
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>Number: 159064
>Category: misc
>Synopsis: MFC request for dtrace to fix "invalid probe specifier"
>Confidential: no
>Severity: serious
>Priority: low
>Responsible: freebsd-bugs
>State: open
>Quarter:
>Keywords:
>Date-Required:
>Class: sw-bug
>Submitter-Id: current-users
>Arrival-Date: Wed Jul 20 19:10:10 UTC 2011
>Closed-Date:
>Last-Modified:
>Originator: Alex Samorukov
>Release: 8.2-STABLE
>Organization:
netart
>Environment:
FreeBSD bsd.home 8.2-STABLE FreeBSD 8.2-STABLE #6: Wed Jul 20 17:26:56 UTC 2011 root@bsd.home:/usr/obj/usr/src/sys/DTRACE amd64
>Description:
I found that my dtrace scripts perfectly running on -CURRENT failing with strange messages on -STABLE. This is example:
bsd# dtrace -n 'device_get_softc:entry{printf("%s",stringof(args[0]->nameunit))}'
dtrace: invalid probe specifier device_get_softc:entry{printf("%s",stringof(args[0]->nameunit))}: in action list: failed to resolve translated type for args[0]
args[0] should be "struct device" type. After debugging i found that it fail in libdrace and fix is already commited to the the HEAD.
See http://svnweb.freebsd.org/base/head/cddl/contrib/opensolaris/lib/libdtrace/common/dt_lex.l?r1=209305&r2=209358 for the actual fix. After applying the patch system resolving symbol correctly:
bsd# dtrace -n 'device_get_softc:entry{printf("%s",stringof(args[0]->nameunit))}'
dtrace: description 'device_get_softc:entry' matched 1 probe
dtrace: buffer size lowered to 2m
^C
CPU ID FUNCTION:NAME
0 19594 device_get_softc:entry est0
7 19594 device_get_softc:entry cpufreq0
7 19594 device_get_softc:entry cpufreq0
>How-To-Repeat:
Run dtrace -n 'device_get_softc:entry{printf("%s",stringof(args[0]->nameunit))}'
on 8-STABLE with dtrace enabled kernel
>Fix:
bsd# diff -u dt_lex.l.orig dt_lex.l.new
--- dt_lex.l.orig 2010-11-08 12:54:55.000000000 +0000
+++ dt_lex.l.new 2010-08-02 13:40:53.000000000 +0000
@@ -44,7 +44,7 @@
#undef input
#undef unput
#else
-/*
+/*
* Define YY_INPUT for flex since input() can't be re-defined.
*/
#define YY_INPUT(buf,result,max_size) \
@@ -59,6 +59,19 @@
buf[n] = *yypcb->pcb_strptr++; \
result = n; \
}
+/*
+ * Do not EOF let tokens to be put back. This does not work with flex.
+ * On the other hand, leaving current buffer in same state it was when
+ * last EOF was received guarantees that input() will keep returning EOF
+ * for all subsequent invocations, which is the effect desired.
+ */
+#undef unput
+#define unput(c) \
+ do { \
+ int _c = c; \
+ if (_c != EOF) \
+ yyunput(_c, yytext_ptr); \
+ } while(0)
#endif
static int id_or_type(const char *);
>Release-Note:
>Audit-Trail:
>Unformatted:
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