Add -K support to gprof(1), which enables dynamic symbol resolution from

the currently-running kernel (and supercedes an executable file argument
given).  With this change, properly-compiled KLD modules are now
able to be profiled.

Obtained from:	NAI Labs CBOSS project
Funded by:	DARPA

5 files changed, 87 insertions, 3 deletions

diff --git a/usr.bin/gprof/Makefile b/usr.bin/gprof/Makefile
index 29291cc..cc5a276 100644
--- a/usr.bin/gprof/Makefile
+++ b/usr.bin/gprof/Makefile
@@ -1,8 +1,9 @@
 #	@(#)Makefile	8.1 (Berkeley) 6/29/93
+#	$FreeBSD$
 
 PROG=	gprof
 SRCS=	gprof.c aout.c arcs.c dfn.c elf.c lookup.c ${MACHINE_ARCH}.c hertz.c \
-	printgprof.c printlist.c
+	printgprof.c printlist.c kernel.c
 
 beforeinstall:
 	${INSTALL} -c -o ${BINOWN} -g ${BINGRP} -m 444 \
diff --git a/usr.bin/gprof/gprof.1 b/usr.bin/gprof/gprof.1
index f421221..fa45baa 100644
--- a/usr.bin/gprof/gprof.1
+++ b/usr.bin/gprof/gprof.1
@@ -208,6 +208,17 @@ option may be given.
 Only one pair of routine names may be given with each
 .Fl k
 option.
+.It Fl K
+Gather information about symbols from the currently-running kernel using the
+.Xr sysctl 3
+and
+.Xr kldsym 2
+interfaces.
+This forces the 
+.Pa a.out
+argument to be ignored, and allows for symbols in
+.Xr kld 4
+modules to be used.
 .It Fl l
 Suppresses the printing of the call-graph profile.
 .It Fl L
diff --git a/usr.bin/gprof/gprof.c b/usr.bin/gprof/gprof.c
index dfb1e2c..79dafc7 100644
--- a/usr.bin/gprof/gprof.c
+++ b/usr.bin/gprof/gprof.c
@@ -125,6 +125,9 @@ main(argc, argv)
 	    addlist( ktolist , *++argv );
 	    kflag = TRUE;
 	    break;
+	case 'K':
+	    Kflag = TRUE;
+	    break;
     case 'l':
 	    lflag = 1;
 	    Lflag = 0;
@@ -162,8 +165,9 @@ main(argc, argv)
 	/*
 	 *	get information from the executable file.
 	 */
-    if (elf_getnfile(a_outname, &defaultEs) == -1 &&
-      aout_getnfile(a_outname, &defaultEs) == -1)
+    if ((Kflag && kernel_getnfile(a_outname, &defaultEs) == -1) ||
+      (elf_getnfile(a_outname, &defaultEs) == -1 &&
+      aout_getnfile(a_outname, &defaultEs) == -1))
 	errx(1, "%s: bad format", a_outname);
 	/*
 	 *	sort symbol table.
diff --git a/usr.bin/gprof/gprof.h b/usr.bin/gprof/gprof.h
index 3a7c54b..ee0976e 100644
--- a/usr.bin/gprof/gprof.h
+++ b/usr.bin/gprof/gprof.h
@@ -238,6 +238,7 @@ bool	Eflag;				/* functions excluded with time */
 bool	fflag;				/* specific functions requested */
 bool	Fflag;				/* functions requested with time */
 bool	kflag;				/* arcs to be deleted */
+bool	Kflag;				/* use the running kernel for symbols */
 bool	sflag;				/* sum multiple gmon.out files */
 bool	uflag;				/* suppress symbols hidden from C */
 bool	zflag;				/* zero time/called functions, too */
@@ -295,6 +296,9 @@ int		elf_getnfile(const char *, char ***);
 		getpfile();
 		gprofheader();
 		gprofline();
+*/
+int		kernel_getnfile(const char *, char ***);
+/*
 		main();
 */
 unsigned long	max();
diff --git a/usr.bin/gprof/kernel.c b/usr.bin/gprof/kernel.c
new file mode 100644
index 0000000..c8df0d0
--- /dev/null
+++ b/usr.bin/gprof/kernel.c
@@ -0,0 +1,64 @@
+#ifndef lint
+static const char rcsid[] =
+  "$FreeBSD$";
+#endif /* not lint */
+
+#include <sys/param.h>
+#include <sys/linker.h>
+#include <sys/sysctl.h>
+#include <sys/errno.h>
+
+#include <err.h>
+#include <stdlib.h>
+
+#include "gprof.h"
+
+/* Things which get -E excluded by default. */
+static char	*excludes[] = { ".mcount", "_mcleanup", NULL };
+
+int
+kernel_getnfile(const char *unused, char ***defaultEs)
+{
+	char *namelist;
+	size_t len;
+	char *name;
+
+	if (sysctlbyname("kern.function_list", NULL, &len, NULL, 0) == -1)
+		err(1, "sysctlbyname: function_list size");
+	for (;;) {
+		namelist = malloc(len);
+		if (namelist == NULL)
+			err(1, "malloc");
+		if (sysctlbyname("kern.function_list", namelist, &len, NULL,
+		   0) == 0)
+			break;
+		if (errno == ENOMEM)
+			free(namelist);
+		else
+			err(1, "sysctlbyname: function_list");
+	}
+	nname = 0;
+	for (name = namelist; *name != '\0'; name += strlen(name) + 1)
+		nname++;
+	/* Allocate memory for them, plus a terminating entry. */
+	if ((nl = (nltype *)calloc(nname + 1, sizeof(nltype))) == NULL)
+		errx(1, "Insufficient memory for symbol table");
+	npe = nl;
+	for (name = namelist; *name != '\0'; name += strlen(name) + 1) {
+		struct kld_sym_lookup ksl;
+
+		ksl.version = sizeof(ksl);
+		ksl.symname = name;
+		if (kldsym(0, KLDSYM_LOOKUP, &ksl))
+			err(1, "kldsym(%s)", name);
+		/* aflag not supported */
+		if (uflag && strchr(name, '.') != NULL)
+			continue;
+		npe->value = ksl.symvalue;
+		npe->name = name;
+		npe++;
+	}
+	npe->value = -1;
+
+	*defaultEs = excludes;
+}