OS-3643 lx brand: add USDT provider to lx_brand.so.1

OS-3644 lx brand: ptrace_init() never called

14 files changed, 132 insertions, 15 deletions

diff --git a/usr/src/Makefile.master.64 b/usr/src/Makefile.master.64
index 79ed039f66..c512cfc004 100644
--- a/usr/src/Makefile.master.64
+++ b/usr/src/Makefile.master.64
@@ -21,6 +21,7 @@
 #
 # Copyright (c) 1997, 2010, Oracle and/or its affiliates. All rights reserved.
 # Copyright 2014 Garrett D'Amore <garrett@damore.org>
+# Copyright (c) 2014 Joyent, Inc.  All rights reserved.
 #
 
 # rebind basic build macros to 64-bit versions
@@ -68,7 +69,7 @@ REAL_CC=	$(CW_CC_CMD:sh)
 REAL_CCC=	$(CW_CCC_CMD:sh)
 
 BUILD.SO=	$(CC) $(CFLAGS) -o $@ $(GSHARED) $(DYNFLAGS) \
-		$(PICS) $(EXTPICS) -L $(ROOTLIBDIR64) $(LDLIBS)
+		$(PICS) $(EXTPICS) $(USDT_PICS) -L $(ROOTLIBDIR64) $(LDLIBS)
 
 #
 # ld(1) requires the -64 option to create a 64-bit filter solely from a mapfile
diff --git a/usr/src/lib/Makefile.lib b/usr/src/lib/Makefile.lib
index eeb89960f4..eb5ccb1db6 100644
--- a/usr/src/lib/Makefile.lib
+++ b/usr/src/lib/Makefile.lib
@@ -19,6 +19,7 @@
 # CDDL HEADER END
 #
 # Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2014, Joyent, Inc.
 #
 #
 # Definitions common to libraries.
@@ -134,6 +135,23 @@ SONAME=		$(DYNLIB)
 # combining relocations into one relocation table reduces startup costs.
 # All options are tunable to allow overload/omission from lower makefiles.
 
+#
+# DTrace related rules
+#
+# These allow for multiple USDT providers to be specified by a library.
+# If a library needs to break up the set of objects that are passed to
+# the dtrace -G invocation, then they can place the following in heir
+# Makefile.com:
+#
+# pics/<provider>.o	:= USDT_G_PICS = <files>
+#
+# <provider> should be replaced with the basename of one of the USDT
+# providers specified in USDT_PROVIDERS in their Makefile.com.
+#
+USDT_HEADERS=	$(USDT_PROVIDERS:%.d=%_impl.h)
+USDT_PICS=	$(USDT_PROVIDERS:%.d=pics/%.o)
+USDT_G_PICS=	$(PICS)
+
 
 HSONAME=	-h$(SONAME)
 DYNFLAGS=	$(HSONAME) $(ZTEXT) $(ZDEFS) $(BDIRECT) \
@@ -155,7 +173,8 @@ SRCS=		$(OBJECTS:%.o=$(SRCDIR)/%.c)
 # default build of an archive and a shared object,
 # overridden locally when extra processing is needed
 BUILD.AR=	$(AR) $(ARFLAGS) $@ $(AROBJS)
-BUILD.SO=	$(CC) -o $@ $(GSHARED) $(DYNFLAGS) $(PICS) $(EXTPICS) $(LDLIBS)
+BUILD.SO=	$(CC) -o $@ $(GSHARED) $(DYNFLAGS) $(PICS) $(EXTPICS) \
+		$(USDT_PICS) $(LDLIBS)
 BUILDCCC.SO=	$(CCC) -o $@ $(GSHARED) $(DYNFLAGS) $(PICS) $(EXTPICS) $(LDLIBS)
 
 # default dynamic library symlink
diff --git a/usr/src/lib/Makefile.targ b/usr/src/lib/Makefile.targ
index 61cb45969d..2798192343 100644
--- a/usr/src/lib/Makefile.targ
+++ b/usr/src/lib/Makefile.targ
@@ -20,6 +20,7 @@
 #
 #
 # Copyright (c) 1989, 2010, Oracle and/or its affiliates. All rights reserved.
+# Copyright (c) 2014, Joyent, Inc.
 #
 
 #
@@ -90,7 +91,7 @@ $(LIBRARY): objs .WAIT $$(OBJS)
 
 $(DYNLIB): $$(MAPFILES)
 
-$(DYNLIB): pics .WAIT $$(PICS) $$(ALTPICS) $$(EXTPICS)
+$(DYNLIB): pics $(USDT_HEADERS) .WAIT $$(PICS) $$(ALTPICS) $$(EXTPICS) .WAIT $(USDT_PICS)
 	$(BUILD.SO)
 	$(POST_PROCESS_SO)
 
@@ -111,5 +112,5 @@ clobber: clean
 	-$(RM) $(CLOBBERTARGFILES)
 
 clean:
-	-$(RM) $(OBJS)
+	-$(RM) $(OBJS) $(USDT_HEADERS) $(USDT_PICS)
 	-$(RM) $(PICS) $(DUPLICATE_SRC) $(LINTOUT) $(LINTLIB) $(CLEANFILES)
diff --git a/usr/src/lib/Makefile.usdt b/usr/src/lib/Makefile.usdt
new file mode 100644
index 0000000000..17140161ad
--- /dev/null
+++ b/usr/src/lib/Makefile.usdt
@@ -0,0 +1,28 @@
+#
+# This file and its contents are supplied under the terms of the
+# Common Development and Distribution License ("CDDL"), version 1.0.
+# You may only use this file in accordance with the terms of version
+# 1.0 of the CDDL.
+#
+# A full copy of the text of the CDDL should have accompanied this
+# source.  A copy of the CDDL is also available via the Internet at
+# http://www.illumos.org/license/CDDL.
+#
+
+#
+# Copyright (c) 2014 Joyent, Inc.  All rights reserved.
+#
+
+#
+# This makefile contains the necessary targets for USDT providers; it should
+# be included after Makefile.targ.  (It is in a separate file rather than in
+# Makefile.targ because the dependency on $(USDT_G_PICS) is incompatible with
+# libraries that dynamically define $(OBJECTS).)
+#
+pics/%.o: $(SRCDIR)/%.d $(USDT_G_PICS)
+	$(COMPILE.d) -o $@ -s $< $(USDT_G_PICS)
+	$(POST_PROCESS_O)
+
+%_impl.h: $(SRCDIR)/%.d
+	$(DTRACE) -h -o $@ -s $<
+
diff --git a/usr/src/lib/brand/lx/lx_brand/Makefile.com b/usr/src/lib/brand/lx/lx_brand/Makefile.com
index 2c9021ac1d..3e6f122973 100644
--- a/usr/src/lib/brand/lx/lx_brand/Makefile.com
+++ b/usr/src/lib/brand/lx/lx_brand/Makefile.com
@@ -67,6 +67,8 @@ CMNOBJS =	lx_signum.o
 ASOBJS	=	lx_handler.o lx_runexe.o lx_crt.o
 OBJECTS	=	$(CMNOBJS) $(COBJS) $(ASOBJS)
 
+USDT_PROVIDERS =	lx_provider.d
+
 include ../../Makefile.lx
 include ../../../../Makefile.lib
 
@@ -82,7 +84,7 @@ LDLIBS +=	-lc -lsocket -lmapmalloc -lproc -lrtld_db
 DYNFLAGS +=	$(DYNFLAGS_$(CLASS))
 DYNFLAGS +=	$(BLOCAL) $(ZNOVERSION) -Wl,-e_start -M../common/mapfile
 CFLAGS +=	$(CCVERBOSE)
-CPPFLAGS +=	-D_REENTRANT -I../ -I$(UTSBASE)/common/brand/lx -I$(LX_CMN)
+CPPFLAGS +=	-D_REENTRANT -I. -I../ -I$(UTSBASE)/common/brand/lx -I$(LX_CMN)
 ASFLAGS =	-P $(ASFLAGS_$(CURTYPE)) -D_ASM -I../	\
 			-I$(UTSBASE)/common/brand/lx
 
@@ -93,6 +95,7 @@ all: $(LIBS)
 lint: lintcheck
 
 include ../../../../Makefile.targ
+include ../../../../Makefile.usdt
 
 pics/%.o: $(ISASRCDIR)/%.s
 	$(COMPILE.s) -o $@ $<
diff --git a/usr/src/lib/brand/lx/lx_brand/common/debug.c b/usr/src/lib/brand/lx/lx_brand/common/debug.c
index 77131c70d3..7e58a0f941 100644
--- a/usr/src/lib/brand/lx/lx_brand/common/debug.c
+++ b/usr/src/lib/brand/lx/lx_brand/common/debug.c
@@ -46,6 +46,8 @@
 static char	*lx_debug_path = NULL;		/* debug output file path */
 static char	lx_debug_path_buf[MAXPATHLEN];
 
+int		lx_dtrace_lazyload = 1;		/* patchable; see below */
+
 void
 lx_debug_enable(void)
 {
@@ -57,6 +59,24 @@ lx_debug_enable(void)
 void
 lx_debug_init(void)
 {
+	/*
+	 * Our DTrace USDT provider is loaded in our .init section, which is
+	 * not run by our e_entry ELF entry point (_start, which calls into
+	 * lx_init()).  We exploit this to only actually load our USDT provider
+	 * if LX_DTRACE is set, assuring that we don't compromise fork()
+	 * performance in the (common) case that DTrace of lx_brand.so.1 itself
+	 * isn't enabled or desired. (As with all USDT providers, it can always
+	 * be loaded by explicitly specifying the full provider name).  Note
+	 * that we also allow this behavior to be set via a manual override,
+	 * lx_dtrace_lazyload -- allowing for USDT probes to be automatically
+	 * provided in situations where setting an environment variable is
+	 * tedious or otherwise impossible.
+	 */
+	if (getenv("LX_DTRACE") != NULL || !lx_dtrace_lazyload) {
+		extern void _init(void);
+		_init();
+	}
+
 	if (getenv("LX_DEBUG") == NULL)
 		return;
 
@@ -95,7 +115,7 @@ lx_debug(const char *msg, ...)
 	int		errno_backup;
 	int		size = LX_MSG_MAXLEN + 1;
 
-	if (lx_debug_enabled == 0)
+	if (lx_debug_enabled == 0 && !LX_DEBUG_ENABLED())
 		return;
 
 	/*
@@ -130,6 +150,11 @@ lx_debug(const char *msg, ...)
 		return;
 	}
 
+	LX_DEBUG(buf);
+
+	if (!lx_debug_enabled)
+		return;
+
 	/*
 	 * Open the debugging output file.  note that we don't protect
 	 * ourselves against exec or fork1 here.  if an mt process were
diff --git a/usr/src/lib/brand/lx/lx_brand/common/lx_brand.c b/usr/src/lib/brand/lx/lx_brand/common/lx_brand.c
index c4071d185d..7700509687 100644
--- a/usr/src/lib/brand/lx/lx_brand/common/lx_brand.c
+++ b/usr/src/lib/brand/lx/lx_brand/common/lx_brand.c
@@ -292,7 +292,7 @@ i_lx_msg(int fd, char *msg, va_list ap)
 		return;
 
 	/* if debugging is enabled, send this message to debug output */
-	if (lx_debug_enabled != 0)
+	if (LX_DEBUG_ISENABLED)
 		lx_debug(buf);
 
 	if (fd == 2) {
@@ -573,7 +573,7 @@ lx_emulate(lx_regs_t *rp)
 		goto out;
 	}
 
-	if (lx_debug_enabled != 0) {
+	if (LX_DEBUG_ISENABLED) {
 		const char *fmt = NULL;
 
 		switch (s->sy_narg) {
@@ -893,6 +893,8 @@ lx_init(int argc, char *argv[], char *envp[])
 	if (lx_statfs_init() != 0)
 		lx_err_fatal("failed to setup the statfs translator");
 
+	lx_ptrace_init();
+
 #if defined(_LP64)
 	vdso_hdr = map_vdso();
 #endif
diff --git a/usr/src/lib/brand/lx/lx_brand/common/lx_provider.d b/usr/src/lib/brand/lx/lx_brand/common/lx_provider.d
new file mode 100644
index 0000000000..2a07c00c7a
--- /dev/null
+++ b/usr/src/lib/brand/lx/lx_brand/common/lx_provider.d
@@ -0,0 +1,27 @@
+/*
+ * This file and its contents are supplied under the terms of the
+ * Common Development and Distribution License ("CDDL"), version 1.0.
+ * You may only use this file in accordance with the terms of version
+ * 1.0 of the CDDL.
+ *
+ * A full copy of the text of the CDDL should have accompanied this
+ * source.  A copy of the CDDL is also available via the Internet at
+ * http://www.illumos.org/license/CDDL.
+ */
+
+/*
+ * Copyright (c) 2014 Joyent, Inc.  All rights reserved.
+ */
+
+provider lx {
+	probe debug(char *buf);
+	probe sigdeliver(int sig, void *lx_sigaction, void *lx_sigstack,
+	    void *lx_ucontext);
+	probe sigreturn(void *lx_ucontext, void *ucontext, uintptr_t sp);
+};
+
+#pragma D attributes Evolving/Evolving/ISA provider lx provider
+#pragma D attributes Private/Private/Unknown provider lx module
+#pragma D attributes Private/Private/Unknown provider lx function
+#pragma D attributes Private/Private/ISA provider lx name
+#pragma D attributes Private/Private/ISA provider lx args
diff --git a/usr/src/lib/brand/lx/lx_brand/common/mem.c b/usr/src/lib/brand/lx/lx_brand/common/mem.c
index cebe2ec5bb..416596ae88 100644
--- a/usr/src/lib/brand/lx/lx_brand/common/mem.c
+++ b/usr/src/lib/brand/lx/lx_brand/common/mem.c
@@ -93,7 +93,7 @@ mmap_common(uintptr_t p1, uintptr_t p2, uintptr_t p3, uintptr_t p4,
 	off64_t off = p6;
 	void *ret;
 
-	if (lx_debug_enabled != 0) {
+	if (LX_DEBUG_ISENABLED) {
 		char *path, path_buf[MAXPATHLEN];
 
 		path = lx_fd_to_path(fd, path_buf, sizeof (path_buf));
diff --git a/usr/src/lib/brand/lx/lx_brand/common/ptrace.c b/usr/src/lib/brand/lx/lx_brand/common/ptrace.c
index e43a38973a..06d5a583fa 100644
--- a/usr/src/lib/brand/lx/lx_brand/common/ptrace.c
+++ b/usr/src/lib/brand/lx/lx_brand/common/ptrace.c
@@ -259,9 +259,8 @@ extern void *_START_;
 
 static sigset_t blockable_sigs;
 
-#pragma init(ptrace_init)
 void
-ptrace_init(void)
+lx_ptrace_init(void)
 {
 	(void) sigfillset(&blockable_sigs);
 	(void) sigdelset(&blockable_sigs, SIGKILL);
diff --git a/usr/src/lib/brand/lx/lx_brand/common/signal.c b/usr/src/lib/brand/lx/lx_brand/common/signal.c
index 1ba48cc0ea..8c4b6926f3 100644
--- a/usr/src/lib/brand/lx/lx_brand/common/signal.c
+++ b/usr/src/lib/brand/lx/lx_brand/common/signal.c
@@ -41,6 +41,7 @@
 #include <sys/lx_syscall.h>
 #include <sys/lx_thread.h>
 #include <sys/syscall.h>
+#include <lx_provider_impl.h>
 #include <assert.h>
 #include <errno.h>
 #include <poll.h>
@@ -1096,6 +1097,7 @@ lx_rt_sigreturn(void)
 	ucp = (ucontext_t *)(*(ssize_t *)(sp + 24));
 
 	lx_ucp = &lx_ssp->uc;
+	LX_SIGRETURN(lx_ucp, ucp, sp);
 
 	/*
 	 * General register layout is completely different.
@@ -1448,6 +1450,8 @@ lx_build_signal_frame(int lx_sig, siginfo_t *sip, void *p, void *sp)
 	    sizeof (lx_ssp->trampoline));
 #endif
 
+	LX_SIGDELIVER(lx_sig, lxsap, lx_ssp, lx_ucp);
+
 #if defined(_LP64)
 	/*
 	 * For the 64-bit code this must be the last syscall we do in the
diff --git a/usr/src/lib/brand/lx/lx_brand/common/stat.c b/usr/src/lib/brand/lx/lx_brand/common/stat.c
index b1c9b18722..7c2b5008f6 100644
--- a/usr/src/lib/brand/lx/lx_brand/common/stat.c
+++ b/usr/src/lib/brand/lx/lx_brand/common/stat.c
@@ -56,6 +56,7 @@
 #include <sys/lx_audio.h>
 #include <sys/lx_fcntl.h>
 #include <sys/lx_syscall.h>
+#include <sys/lx_debug.h>
 #include <sys/modctl.h>
 
 /* define _KERNEL to get the devt manipulation macros */
@@ -242,7 +243,7 @@ s2l_dev_report(dev_t dev, lx_dev_t jdev)
 	minor_t			min;
 	int			lx_maj, lx_min;
 
-	if (lx_debug_enabled == 0)
+	if (!LX_DEBUG_ISENABLED)
 		return;
 
 	maj = getmajor(dev);
@@ -410,7 +411,7 @@ lx_fstat(uintptr_t p1, uintptr_t p2)
 	struct stat	sbuf;
 	char		*path, path_buf[MAXPATHLEN];
 
-	if (lx_debug_enabled != 0) {
+	if (LX_DEBUG_ISENABLED) {
 		path = lx_fd_to_path(fd, path_buf, sizeof (path_buf));
 		if (path == NULL)
 			path = "?";
diff --git a/usr/src/lib/brand/lx/lx_brand/sys/lx_debug.h b/usr/src/lib/brand/lx/lx_brand/sys/lx_debug.h
index 80fb579665..57692cfcd1 100644
--- a/usr/src/lib/brand/lx/lx_brand/sys/lx_debug.h
+++ b/usr/src/lib/brand/lx/lx_brand/sys/lx_debug.h
@@ -23,10 +23,14 @@
  * Use is subject to license terms.
  */
 
+/*
+ * Copyright (c) 2014 Joyent, Inc.  All rights reserved.
+ */
+
 #ifndef	_LX_DEBUG_H
 #define	_LX_DEBUG_H
 
-#pragma ident	"%Z%%M%	%I%	%E% SMI"
+#include <lx_provider_impl.h>
 
 #ifdef	__cplusplus
 extern "C" {
@@ -38,9 +42,11 @@ extern void lx_debug_init(void);
 /* printf() style debug message functionality */
 extern void lx_debug(const char *, ...);
 
-/* set non-zero if the debugging subsystem is enabled */
 extern int lx_debug_enabled;
 
+#define	LX_DEBUG_ISENABLED	\
+	(lx_debug_enabled || LX_DEBUG_ENABLED())
+
 #ifdef	__cplusplus
 }
 #endif
diff --git a/usr/src/lib/brand/lx/lx_brand/sys/lx_misc.h b/usr/src/lib/brand/lx/lx_brand/sys/lx_misc.h
index 220ae0b48f..76c75e919e 100644
--- a/usr/src/lib/brand/lx/lx_brand/sys/lx_misc.h
+++ b/usr/src/lib/brand/lx/lx_brand/sys/lx_misc.h
@@ -169,6 +169,7 @@ extern char *lx_fd_to_path(int fd, char *buf, int buf_size);
 extern int lx_lpid_to_spair(pid_t, pid_t *, lwpid_t *);
 extern int lx_lpid_to_spid(pid_t, pid_t *);
 
+extern void lx_ptrace_init();
 extern int lx_ptrace_wait(siginfo_t *);
 extern void lx_ptrace_fork(void);
 extern void lx_ptrace_stop_if_option(int);