From c71b9e1d88558f59468f118b14b982838a1f2dba Mon Sep 17 00:00:00 2001
From: markj <markj@ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f>
Date: Tue, 29 Jul 2014 18:31:44 +0000
Subject: [PATCH] MFC r262669: When our linker merges .SUNW_dof sections from
 multiple files, it simply concatenates the DOF tables into one section.
 Previously, the USDT init code in drti.o would only look at the first table
 in the DOF section; with this change, it iterates over all the tables,
 passing each DOF table to the kernel.

PR:	186821


git-svn-id: svn://svn.freebsd.org/base/stable/9@269246 ccf9f872-aa2e-dd11-9fc8-001c23d0bc1f
---
 .../opensolaris/lib/libdtrace/common/drti.c   | 88 ++++++++++++-------
 1 file changed, 58 insertions(+), 30 deletions(-)

diff --git a/cddl/contrib/opensolaris/lib/libdtrace/common/drti.c b/cddl/contrib/opensolaris/lib/libdtrace/common/drti.c
index 3b4a38ce3..bb02d8cf4 100644
--- a/cddl/contrib/opensolaris/lib/libdtrace/common/drti.c
+++ b/cddl/contrib/opensolaris/lib/libdtrace/common/drti.c
@@ -20,6 +20,7 @@
  */
 /*
  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
+ * Copyright 2013 Voxer Inc. All rights reserved.
  * Use is subject to license terms.
  */
 
@@ -144,7 +145,8 @@ dtrace_dof_init(void)
 	Lmid_t lmid;
 #else
 	u_long lmid = 0;
-	dof_sec_t *sec;
+	dof_sec_t *sec, *secstart, *dofstrtab, *dofprobes;
+	dof_provider_t *dofprovider;
 	size_t i;
 #endif
 	int fd;
@@ -152,14 +154,15 @@ dtrace_dof_init(void)
 #if !defined(sun)
 	Elf *e;
 	Elf_Scn *scn = NULL;
-	Elf_Data *symtabdata = NULL, *dynsymdata = NULL;
+	Elf_Data *symtabdata = NULL, *dynsymdata = NULL, *dofdata = NULL;
+	dof_hdr_t *dof_next = NULL;
 	GElf_Shdr shdr;
 	int efd, nprobes;
 	char *s;
+	char *dofstrtabraw;
 	size_t shstridx, symtabidx = 0, dynsymidx = 0;
-	unsigned char *dofstrtab = NULL;
 	unsigned char *buf;
-	int fixedprobes = 0;
+	int fixedprobes;
 #endif
 
 	if (getenv("DTRACE_DOF_INIT_DISABLE") != NULL)
@@ -209,7 +212,8 @@ dtrace_dof_init(void)
 		} else if (shdr.sh_type == SHT_PROGBITS) {
 			s = elf_strptr(e, shstridx, shdr.sh_name);
 			if  (s && strcmp(s, ".SUNW_dof") == 0) {
-				dof = elf_getdata(scn, NULL)->d_buf;
+				dofdata = elf_getdata(scn, NULL);
+				dof = dofdata->d_buf;
 			}
 		}
 	}
@@ -219,6 +223,10 @@ dtrace_dof_init(void)
 		close(efd);
 		return;
 	}
+
+	while ((char *) dof < (char *) dofdata->d_buf + dofdata->d_size) {
+		fixedprobes = 0;
+		dof_next = (void *) ((char *) dof + dof->dofh_filesz);
 #endif
 
 	if (dof->dofh_ident[DOF_ID_MAG0] != DOF_MAG_MAG0 ||
@@ -290,34 +298,49 @@ dtrace_dof_init(void)
 	 * We are assuming the number of probes is less than the number of
 	 * symbols (libc can have 4k symbols, for example).
 	 */
-	sec = (dof_sec_t *)(dof + 1);
+	secstart = sec = (dof_sec_t *)(dof + 1);
 	buf = (char *)dof;
 	for (i = 0; i < dof->dofh_secnum; i++, sec++) {
-		if (sec->dofs_type == DOF_SECT_STRTAB)
-			dofstrtab = (unsigned char *)(buf + sec->dofs_offset);
-		else if (sec->dofs_type == DOF_SECT_PROBES && dofstrtab)
+		if (sec->dofs_type != DOF_SECT_PROVIDER)
+			continue;
+
+		dofprovider = (void *) (buf + sec->dofs_offset);
+		dofstrtab = secstart + dofprovider->dofpv_strtab;
+		dofprobes = secstart + dofprovider->dofpv_probes;
+
+		if (dofstrtab->dofs_type != DOF_SECT_STRTAB) {
+			fprintf(stderr, "WARNING: expected STRTAB section, but got %d\n",
+					dofstrtab->dofs_type);
 			break;
-	
-	}
-	nprobes = sec->dofs_size / sec->dofs_entsize;
-	fixsymbol(e, symtabdata, symtabidx, nprobes, buf, sec, &fixedprobes,
-	    dofstrtab);
-	if (fixedprobes != nprobes) {
-		/*
-		 * If we haven't fixed all the probes using the
-		 * symtab section, look inside the dynsym
-		 * section.
-		 */
-		fixsymbol(e, dynsymdata, dynsymidx, nprobes, buf, sec,
-		    &fixedprobes, dofstrtab);
-	}
-	if (fixedprobes != nprobes) {
-		fprintf(stderr, "WARNING: number of probes "
-		    "fixed does not match the number of "
-		    "defined probes (%d != %d, "
-		    "respectively)\n", fixedprobes, nprobes);
-		fprintf(stderr, "WARNING: some probes might "
-		    "not fire or your program might crash\n");
+		}
+		if (dofprobes->dofs_type != DOF_SECT_PROBES) {
+			fprintf(stderr, "WARNING: expected PROBES section, but got %d\n",
+			    dofprobes->dofs_type);
+			break;
+		}
+
+		dprintf(1, "found provider %p\n", dofprovider);
+		dofstrtabraw = (char *)(buf + dofstrtab->dofs_offset);
+		nprobes = dofprobes->dofs_size / dofprobes->dofs_entsize;
+		fixsymbol(e, symtabdata, symtabidx, nprobes, buf, dofprobes, &fixedprobes,
+				dofstrtabraw);
+		if (fixedprobes != nprobes) {
+			/*
+			 * If we haven't fixed all the probes using the
+			 * symtab section, look inside the dynsym
+			 * section.
+			 */
+			fixsymbol(e, dynsymdata, dynsymidx, nprobes, buf, dofprobes,
+					&fixedprobes, dofstrtabraw);
+		}
+		if (fixedprobes != nprobes) {
+			fprintf(stderr, "WARNING: number of probes "
+			    "fixed does not match the number of "
+			    "defined probes (%d != %d, "
+			    "respectively)\n", fixedprobes, nprobes);
+			fprintf(stderr, "WARNING: some probes might "
+			    "not fire or your program might crash\n");
+		}
 	}
 #endif
 	if ((gen = ioctl(fd, DTRACEHIOC_ADDDOF, &dh)) == -1)
@@ -330,7 +353,12 @@ dtrace_dof_init(void)
 	}
 
 	(void) close(fd);
+
 #if !defined(sun)
+		/* End of while loop */
+		dof = dof_next;
+	}
+
 	elf_end(e);
 	(void) close(efd);
 #endif
-- 
2.45.0