git: 2179a159ea93 - main - libdtrace: Add kinst support

The branch main has been updated by markj:

URL: https://cgit.FreeBSD.org/src/commit/?id=2179a159ea93e37b7fb2126ae0b1627b875f808b

commit 2179a159ea93e37b7fb2126ae0b1627b875f808b
Author:     Christos Margiolis <christos@FreeBSD.org>
AuthorDate: 2022-10-11 15:33:52 +0000
Commit:     Mark Johnston <markj@FreeBSD.org>
CommitDate: 2022-10-11 22:19:08 +0000

    libdtrace: Add kinst support
    
    kinst does not instantiate its probes automatically, it only does so on
    demand via an ioctl interface implemented by /dev/kinst.  This change
    modifies libdtrace to perform that work when the script references the
    kinst provider, similar to the way pid provider probes are implemented.
    
    Reviewed by:    markj
    MFC after:      3 months
    Sponsored by:   Google, Inc. (GSoC 2022)
    Differential Revision:  https://reviews.freebsd.org/D36852
---
 .../opensolaris/lib/libdtrace/common/dt_impl.h     |  1 +
 .../opensolaris/lib/libdtrace/common/dt_open.c     |  3 +++
 .../opensolaris/lib/libdtrace/common/dt_provider.c | 29 ++++++++++++++++++++++
 cddl/lib/libdtrace/Makefile                        |  1 +
 4 files changed, 34 insertions(+)

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_impl.h b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_impl.h
index b3f69bb6329d..1e62bd6b21db 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_impl.h
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_impl.h
@@ -323,6 +323,7 @@ struct dtrace_hdl {
 #endif
 	int dt_fd;		/* file descriptor for dtrace pseudo-device */
 	int dt_ftfd;		/* file descriptor for fasttrap pseudo-device */
+	int dt_kinstfd;		/* file descriptor for kinst pseudo-device */
 	int dt_fterr;		/* saved errno from failed open of dt_ftfd */
 	int dt_cdefs_fd;	/* file descriptor for C CTF debugging cache */
 	int dt_ddefs_fd;	/* file descriptor for D CTF debugging cache */
diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_open.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_open.c
index 9621a0fcb391..867259b5d77c 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_open.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_open.c
@@ -1173,6 +1173,7 @@ alloc:
 	dtp->dt_version = version;
 	dtp->dt_fd = dtfd;
 	dtp->dt_ftfd = ftfd;
+	dtp->dt_kinstfd = -1;
 	dtp->dt_fterr = fterr;
 	dtp->dt_cdefs_fd = -1;
 	dtp->dt_ddefs_fd = -1;
@@ -1681,6 +1682,8 @@ dtrace_close(dtrace_hdl_t *dtp)
 		(void) close(dtp->dt_fd);
 	if (dtp->dt_ftfd != -1)
 		(void) close(dtp->dt_ftfd);
+	if (dtp->dt_kinstfd != -1)
+		(void) close(dtp->dt_kinstfd);
 	if (dtp->dt_cdefs_fd != -1)
 		(void) close(dtp->dt_cdefs_fd);
 	if (dtp->dt_ddefs_fd != -1)
diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_provider.c b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_provider.c
index 7cf352d4d505..2391690afc0b 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/dt_provider.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/dt_provider.c
@@ -48,6 +48,7 @@
 #include <dt_list.h>
 #include <dt_pid.h>
 #include <dtrace.h>
+#include <kinst.h>
 
 static dt_provider_t *
 dt_provider_insert(dtrace_hdl_t *dtp, dt_provider_t *pvp, uint_t h)
@@ -699,6 +700,34 @@ dt_probe_info(dtrace_hdl_t *dtp,
 			prp = idp->di_data;
 		else if (pdp->dtpd_id != DTRACE_IDNONE)
 			prp = dt_probe_discover(pvp, pdp);
+
+		if (strcmp(pvp->pv_desc.dtvd_name, "kinst") == 0) {
+			dtrace_kinst_probedesc_t pd;
+
+			if (dtp->dt_kinstfd == -1) {
+				int fd;
+
+				fd = open("/dev/dtrace/kinst", O_WRONLY);
+				if (fd < 0) {
+					(void) dt_set_errno(dtp, errno);
+					return (NULL);
+				}
+				dtp->dt_kinstfd = fd;
+			}
+			memset(&pd, 0, sizeof(pd));
+			strlcpy(pd.kpd_func, pdp->dtpd_func,
+			    sizeof (pd.kpd_func));
+
+			if (n_is_glob)
+				pd.kpd_off = -1;
+			else
+				pd.kpd_off = strtol(pdp->dtpd_name, NULL, 10);
+			if (ioctl(dtp->dt_kinstfd, KINSTIOC_MAKEPROBE, &pd) !=
+			    0) {
+				(void) dt_set_errno(dtp, errno);
+				return (NULL);
+			}
+		}
 	}
 
 	/*
diff --git a/cddl/lib/libdtrace/Makefile b/cddl/lib/libdtrace/Makefile
index f95517f10ebb..651609409a3a 100644
--- a/cddl/lib/libdtrace/Makefile
+++ b/cddl/lib/libdtrace/Makefile
@@ -84,6 +84,7 @@ CFLAGS+= -DHAVE_ISSETUGID
 
 CFLAGS+=	-I${.OBJDIR} -I${.CURDIR} \
 		-I${SRCTOP}/sys/cddl/dev/dtrace/${MACHINE_ARCH} \
+		-I${SRCTOP}/sys/cddl/dev/kinst \
 		-I${SRCTOP}/sys/cddl/compat/opensolaris \
 		-I${SRCTOP}/cddl/compat/opensolaris/include \
 		-I${OPENSOLARIS_USR_DISTDIR}/head \