Hook up support for userland CTF support in DTrace. This required some

modifications to libproc to support fetching the CTF info for a given file.

With this change, dtrace(1) is able to resolve type info for function and
USDT probe arguments, and function return values. In particular, the args[n]
syntax should now work for referencing arguments of userland probes,
provided that the requisite CTF info is available.

The uctf tests pass if the test programs are compiled with CTF info. The
current infrastructure around the DTrace test suite doesn't support this
yet.

Differential Revision:	https://reviews.freebsd.org/D891
MFC after:		1 month
Relnotes:		yes
Sponsored by:		EMC / Isilon Storage Division

ObsoleteFiles.inc

@@ -1496,6 +1496,7 @@ OLD_LIBS+=usr/lib/libpanel.so.4
 OLD_LIBS+=usr/lib/libpanelw.so.4
 OLD_LIBS+=usr/lib/libpmc.so.4
 OLD_LIBS+=usr/lib/libproc.so.1
+OLD_LIBS+=usr/lib/libproc.so.2
 OLD_LIBS+=usr/lib/libradius.so.3
 OLD_LIBS+=usr/lib/librpcsvc.so.4
 OLD_LIBS+=usr/lib/libsdp.so.3

cddl/contrib/opensolaris/cmd/dtrace/test/tst/common/uctf/tst.userlandkey.ksh

@@ -38,7 +38,7 @@ fi
 ./$exe &
 pid=$!
 
-$dtrace -32 -qs /dev/stdin <<EOF
+$dtrace -qs /dev/stdin <<EOF
 typedef struct info {
         char    *zi_gamename;
         int     zi_ndungeons;

cddl/contrib/opensolaris/lib/libdtrace/common/dt_pid.c

@@ -434,15 +434,10 @@ static const prmap_t *
 dt_pid_fix_mod(dtrace_probedesc_t *pdp, struct ps_prochandle *P)
 {
 	char m[MAXPATHLEN];
-#if defined(sun)
 	Lmid_t lmid = PR_LMID_EVERY;
-#else
-	Lmid_t lmid = 0;
-#endif
 	const char *obj;
 	const prmap_t *pmp;
 
-#if defined(sun)
 	/*
 	 * Pick apart the link map from the library name.
 	 */
@@ -463,20 +458,17 @@ dt_pid_fix_mod(dtrace_probedesc_t *pdp, struct ps_prochandle *P)
 	} else {
 		obj = pdp->dtpd_mod;
 	}
-#else
-	obj = pdp->dtpd_mod;
-#endif
 
 	if ((pmp = Plmid_to_map(P, lmid, obj)) == NULL)
 		return (NULL);
 
-#if defined(sun)
 	(void) Pobjname(P, pmp->pr_vaddr, m, sizeof (m));
 	if ((obj = strrchr(m, '/')) == NULL)
 		obj = &m[0];
 	else
 		obj++;
 
+#if defined(sun)
 	(void) Plmid(P, pmp->pr_vaddr, &lmid);
 #endif
 
@@ -571,9 +563,7 @@ dt_pid_usdt_mapping(void *data, const prmap_t *pmp, const char *oname)
 {
 	struct ps_prochandle *P = data;
 	GElf_Sym sym;
-#if defined(sun)
 	prsyminfo_t sip;
-#endif
 	dof_helper_t dh;
 	GElf_Half e_type;
 	const char *mname;
@@ -852,11 +842,7 @@ dt_pid_get_types(dtrace_hdl_t *dtp, const dtrace_probedesc_t *pdp,
 	ctf_funcinfo_t f;
 	ctf_id_t argv[32];
 	GElf_Sym sym;
-#if defined(sun)
 	prsyminfo_t si;
-#else
-	void *si;
-#endif
 	struct ps_prochandle *p;
 	int i, args;
 	char buf[DTRACE_ARGTYPELEN];
@@ -941,13 +927,11 @@ dt_pid_get_types(dtrace_hdl_t *dtp, const dtrace_probedesc_t *pdp,
 		    pdp->dtpd_func, pdp->dtpd_provider, pdp->dtpd_mod);
 		goto out;
 	}
-#if defined(sun)
 	if (ctf_func_info(fp, si.prs_id, &f) == CTF_ERR) {
 		dt_dprintf("failed to get ctf information for %s in %s`%s\n",
 		    pdp->dtpd_func, pdp->dtpd_provider, pdp->dtpd_mod);
 		goto out;
 	}
-#endif
 
 	(void) snprintf(buf, sizeof (buf), "%s`%s", pdp->dtpd_provider,
 	    pdp->dtpd_mod);
@@ -977,7 +961,6 @@ dt_pid_get_types(dtrace_hdl_t *dtp, const dtrace_probedesc_t *pdp,
 		(void) ctf_type_qname(fp, f.ctc_return, adp->dtargd_native +
 		    ret, DTRACE_ARGTYPELEN - ret, buf);
 		*nargs = 2;
-#if defined(sun)
 	} else {
 		if (ctf_func_args(fp, si.prs_id, argc, argv) == CTF_ERR)
 			goto out;
@@ -993,7 +976,6 @@ dt_pid_get_types(dtrace_hdl_t *dtp, const dtrace_probedesc_t *pdp,
 			(void) ctf_type_qname(fp, argv[i], adp->dtargd_native +
 			    ret, DTRACE_ARGTYPELEN - ret, buf);
 		}
-#endif
 	}
 out:
 	dt_proc_unlock(dtp, p);

cddl/lib/libdtrace/libproc_compat.h

@@ -38,7 +38,7 @@
 #define	Pxlookup_by_addr(p, a, n, s, sym, i) \
     proc_addr2sym(p, a, n, s, sym)
 #define	Pxlookup_by_name(p, l, s1, s2, sym, a) \
-    proc_name2sym((p), (s1), (s2), (sym))
+    proc_name2sym(p, s1, s2, sym, a)
 #define	Paddr_to_map proc_addr2map
 #define	Pcreate_error strerror
 #define	Pdelbkpt proc_bkptdel
@@ -46,10 +46,10 @@
 #define	Plmid(p, a, l) (-1)
 #define	Plmid_to_map(p, l, o) proc_obj2map((p), (o))
 #define	Plookup_by_addr proc_addr2sym
-#define	Pname_to_ctf(p, obj) NULL
+#define	Pname_to_ctf(p, obj) (ctf_file_t *)proc_name2ctf(p, obj)
 #define	Pname_to_map proc_name2map
 #define	Pobject_iter proc_iter_objs
-#define	Pobject_iter_resolved(p, f, arg) 1
+#define	Pobject_iter_resolved(p, f, arg) proc_iter_objs(p, f, arg)
 #define	Pobjname proc_objname
 #define	Pread proc_read
 #define	Prd_agent proc_rdagent

lib/libproc/Makefile

@@ -25,7 +25,18 @@ LDADD+=		-lsupc++
 DPADD+=		${LIBSTDCPLUSPLUS}
 .endif
 
-SHLIB_MAJOR=	2
+.if ${MK_CDDL} != "no"
+LDADD+=		-lctf
+DPADD+=		${LIBCTF}
+IGNORE_PRAGMA=	YES
+CFLAGS+=	-I${.CURDIR}/../../cddl/contrib/opensolaris/lib/libctf/common \
+		-I${.CURDIR}/../../sys/cddl/contrib/opensolaris/uts/common \
+		-I${.CURDIR}/../../sys/cddl/compat/opensolaris
+.else
+CFLAGS+=	-DNO_CTF
+.endif
+
+SHLIB_MAJOR=	3
 
 MAN=
 

lib/libproc/libproc.h

@@ -37,6 +37,7 @@
 #include <rtld_db.h>
 #include <limits.h>
 
+struct ctf_file;
 struct proc_handle;
 
 typedef void (*proc_child_func)(void *);
@@ -67,6 +68,11 @@ typedef struct prmap {
 #define	MA_NOCOREDUMP	0x20
 } prmap_t;
 
+typedef struct prsyminfo {
+	u_int		prs_lmid;	/* Map id. */
+	u_int		prs_id;		/* Symbol id. */
+} prsyminfo_t;
+
 typedef int proc_map_f(void *, const prmap_t *, const char *);
 typedef int proc_sym_f(void *, const GElf_Sym *, const char *);
 
@@ -125,7 +131,9 @@ int	proc_create(const char *, char * const *, proc_child_func *, void *,
 	    struct proc_handle **);
 int	proc_detach(struct proc_handle *, int);
 int	proc_getflags(struct proc_handle *);
-int	proc_name2sym(struct proc_handle *, const char *, const char *, GElf_Sym *);
+int	proc_name2sym(struct proc_handle *, const char *, const char *,
+	    GElf_Sym *, prsyminfo_t *);
+struct ctf_file *proc_name2ctf(struct proc_handle *, const char *);
 int	proc_setflags(struct proc_handle *, int);
 int	proc_state(struct proc_handle *);
 pid_t	proc_getpid(struct proc_handle *);
@@ -133,8 +141,7 @@ int	proc_wstatus(struct proc_handle *);
 int	proc_getwstat(struct proc_handle *);
 char *	proc_signame(int, char *, size_t);
 int	proc_read(struct proc_handle *, void *, size_t, size_t);
-const lwpstatus_t *
-	proc_getlwpstatus(struct proc_handle *);
+const lwpstatus_t *proc_getlwpstatus(struct proc_handle *);
 void	proc_free(struct proc_handle *);
 rd_agent_t *proc_rdagent(struct proc_handle *);
 void	proc_updatesyms(struct proc_handle *);

lib/libproc/proc_sym.c

@@ -32,6 +32,10 @@
 __FBSDID("$FreeBSD$");
 
 #include <sys/types.h>
+#ifndef NO_CTF
+#include <sys/ctf.h>
+#include <sys/ctf_api.h>
+#endif
 #include <sys/user.h>
 
 #include <assert.h>
@@ -42,10 +46,17 @@ __FBSDID("$FreeBSD$");
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
+#ifndef NO_CTF
+#include <libctf.h>
+#endif
 #include <libutil.h>
 
 #include "_libproc.h"
 
+#ifdef NO_CTF
+typedef struct ctf_file ctf_file_t;
+#endif
+
 #ifndef NO_CXA_DEMANGLE
 extern char *__cxa_demangle(const char *, char *, size_t *, int *);
 #endif /* NO_CXA_DEMANGLE */
@@ -389,7 +400,7 @@ proc_name2map(struct proc_handle *p, const char *name)
  */
 static int
 lookup_name(Elf *e, Elf_Scn *scn, u_long stridx, const char *symbol,
-    GElf_Sym *symcopy)
+    GElf_Sym *symcopy, prsyminfo_t *si)
 {
 	GElf_Sym sym;
 	Elf_Data *data;
@@ -404,6 +415,8 @@ lookup_name(Elf *e, Elf_Scn *scn, u_long stridx, const char *symbol,
 		s = elf_strptr(e, stridx, sym.st_name);
 		if (s != NULL && strcmp(s, symbol) == 0) {
 			memcpy(symcopy, &sym, sizeof(*symcopy));
+			if (si != NULL)
+				si->prs_id = i;
 			return (0);
 		}
 	}
@@ -412,7 +425,7 @@ lookup_name(Elf *e, Elf_Scn *scn, u_long stridx, const char *symbol,
 
 int
 proc_name2sym(struct proc_handle *p, const char *object, const char *symbol,
-    GElf_Sym *symcopy)
+    GElf_Sym *symcopy, prsyminfo_t *si)
 {
 	Elf *e;
 	Elf_Scn *scn, *dynsymscn = NULL, *symtabscn = NULL;
@@ -462,11 +475,11 @@ proc_name2sym(struct proc_handle *p, const char *object, const char *symbol,
 	 * First look up the symbol in the dynsymtab, and fall back to the
 	 * symtab if the lookup fails.
 	 */
-	error = lookup_name(e, dynsymscn, dynsymstridx, symbol, symcopy);
+	error = lookup_name(e, dynsymscn, dynsymstridx, symbol, symcopy, si);
 	if (error == 0)
 		goto out;
 
-	error = lookup_name(e, symtabscn, symtabstridx, symbol, symcopy);
+	error = lookup_name(e, symtabscn, symtabstridx, symbol, symcopy, si);
 	if (error == 0)
 		goto out;
 
@@ -484,6 +497,26 @@ proc_name2sym(struct proc_handle *p, const char *object, const char *symbol,
 	return (error);
 }
 
+ctf_file_t *
+proc_name2ctf(struct proc_handle *p, const char *name)
+{
+#ifndef NO_CTF
+	prmap_t *map;
+	int error;
+
+	if ((map = proc_name2map(p, name)) == NULL) {
+		DPRINTFX("ERROR: couldn't find object %s", object);
+		return (NULL);
+	}
+
+	return (ctf_open(map->pr_mapname, &error));
+#else
+	(void)p;
+	(void)name;
+	return (NULL);
+#endif
+}
+
 int
 proc_iter_symbyaddr(struct proc_handle *p, const char *object, int which,
     int mask, proc_sym_f *func, void *cd)

lib/libproc/tests/proc_test.c

@@ -227,6 +227,7 @@ ATF_TC_HEAD(map_alias_name2sym, tc)
 ATF_TC_BODY(map_alias_name2sym, tc)
 {
 	GElf_Sym sym1, sym2;
+	prsyminfo_t si1, si2;
 	struct proc_handle *phdl;
 	int error;
 
@@ -239,14 +240,15 @@ ATF_TC_BODY(map_alias_name2sym, tc)
 	 * Make sure that "target_prog:main" and "a.out:main" return the same
 	 * symbol.
 	 */
-	error = proc_name2sym(phdl, target_prog_file, "main", &sym1);
+	error = proc_name2sym(phdl, target_prog_file, "main", &sym1, &si1);
 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'main' via %s",
 	    target_prog_file);
-	error = proc_name2sym(phdl, aout_object, "main", &sym2);
+	error = proc_name2sym(phdl, aout_object, "main", &sym2, &si2);
 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'main' via %s",
 	    aout_object);
 
 	ATF_CHECK_EQ(memcmp(&sym1, &sym2, sizeof(sym1)), 0);
+	ATF_CHECK_EQ(si1.prs_id, si2.prs_id);
 
 	ATF_CHECK_EQ_MSG(proc_continue(phdl), 0, "failed to resume execution");
 
@@ -271,11 +273,11 @@ ATF_TC_BODY(symbol_lookup, tc)
 
 	phdl = start_prog(tc, false);
 
-	error = proc_name2sym(phdl, target_prog_file, "main", &main_sym);
+	error = proc_name2sym(phdl, target_prog_file, "main", &main_sym, NULL);
 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'main'");
 
 	error = proc_name2sym(phdl, ldelf_object, "r_debug_state",
-	    &r_debug_state_sym);
+	    &r_debug_state_sym, NULL);
 	ATF_REQUIRE_EQ_MSG(error, 0, "failed to look up 'r_debug_state'");
 
 	set_bkpt(phdl, r_debug_state_sym.st_value, &saved);

lib/librtld_db/rtld_db.c

@@ -237,14 +237,14 @@ rd_reset(rd_agent_t *rdap)
 	GElf_Sym sym;
 
 	if (proc_name2sym(rdap->rda_php, "ld-elf.so.1", "r_debug_state",
-	    &sym) < 0)
+	    &sym, NULL) < 0)
 		return (RD_ERR);
 	DPRINTF("found r_debug_state at 0x%lx\n", (unsigned long)sym.st_value);
 	rdap->rda_preinit_addr = sym.st_value;
 	rdap->rda_dlactivity_addr = sym.st_value;
 
 	if (proc_name2sym(rdap->rda_php, "ld-elf.so.1", "_r_debug_postinit",
-	    &sym) < 0)
+	    &sym, NULL) < 0)
 		return (RD_ERR);
 	DPRINTF("found _r_debug_postinit at 0x%lx\n",
 	    (unsigned long)sym.st_value);