svn commit: r210063 - head/usr.bin/gcore

[Attilio Rao]

Author: attilio
Date: Wed Jul 14 17:16:25 2010
New Revision: 210063
URL: http://svn.freebsd.org/changeset/base/210063

Log:
  Fix the way the segments are included in the gcore outputs (with the
  default invokation):
  - Right now if segments are not writable are not included. Remove this.
  - Right now if a segment is mapped with NOCORE the check is not honoured.
    Change this by checking the newly added flag, from libutil,
    KVME_FLAG_NOCOREDUMP.
  
  Besides that, add a new flag (-f) that forces a 'full' dump of all the
  segments excluding just the malformed ones. This might be used very
  carefully as, among the reported segments, there could be memory
  mapped areas that could be vital to program execution.
  
  Sponsored by:	Sandvine Incorporated
  Discussed with:	kib
  Reviewed by:	emaste
  Tested by:	Sandvine Incorporated
  MFC after:	2 weeks

Modified:
  head/usr.bin/gcore/elfcore.c
  head/usr.bin/gcore/extern.h
  head/usr.bin/gcore/gcore.1
  head/usr.bin/gcore/gcore.c

Modified: head/usr.bin/gcore/elfcore.c
==============================================================================
--- head/usr.bin/gcore/elfcore.c	Wed Jul 14 16:31:22 2010	(r210062)
+++ head/usr.bin/gcore/elfcore.c	Wed Jul 14 17:16:25 2010	(r210063)
@@ -488,12 +488,17 @@ readmap(pid_t pid)
 		kve = &vmentl[i];
 
 		/*
-		 * Ignore segments of the wrong kind and ones which are not
-		 * readable and writable.
+		 * Ignore 'malformed' segments or ones representing memory
+		 * mapping with MAP_NOCORE on.
+		 * If the 'full' support is disabled, just dump the most
+		 * meaningful data segments.
 		 */
-		if ((kve->kve_protection & KVME_PROT_WRITE) == 0 ||
-		    (kve->kve_protection & KVME_PROT_READ) == 0 ||
-		    (kve->kve_type != KVME_TYPE_DEFAULT &&
+		if ((kve->kve_protection & KVME_PROT_READ) == 0 ||
+		    (kve->kve_flags & KVME_FLAG_NOCOREDUMP) != 0 ||
+		    kve->kve_type == KVME_TYPE_DEAD ||
+		    kve->kve_type == KVME_TYPE_UNKNOWN ||
+		    ((pflags & PFLAGS_FULL) == 0 &&
+		    kve->kve_type != KVME_TYPE_DEFAULT &&
 		    kve->kve_type != KVME_TYPE_VNODE &&
 		    kve->kve_type != KVME_TYPE_SWAP))
 			continue;

Modified: head/usr.bin/gcore/extern.h
==============================================================================
--- head/usr.bin/gcore/extern.h	Wed Jul 14 16:31:22 2010	(r210062)
+++ head/usr.bin/gcore/extern.h	Wed Jul 14 17:16:25 2010	(r210063)
@@ -34,8 +34,11 @@
  * $FreeBSD$
  */
 
+#define	PFLAGS_FULL	0x01
+#define	PFLAGS_RESUME	0x02
+
 struct dumpers {
 	int (*ident)(int efd, pid_t pid, char *binfile);
 	void (*dump)(int efd, int fd, pid_t pid);
 };
-extern int sflag;
+extern int pflags;

Modified: head/usr.bin/gcore/gcore.1
==============================================================================
--- head/usr.bin/gcore/gcore.1	Wed Jul 14 16:31:22 2010	(r210062)
+++ head/usr.bin/gcore/gcore.1	Wed Jul 14 17:16:25 2010	(r210063)
@@ -32,7 +32,7 @@
 .\"	@(#)gcore.1	8.2 (Berkeley) 4/18/94
 .\" $FreeBSD$
 .\"
-.Dd November 18, 2009
+.Dd July 14, 2010
 .Dt GCORE 1
 .Os
 .Sh NAME
@@ -40,6 +40,7 @@
 .Nd get core images of running process
 .Sh SYNOPSIS
 .Nm
+.Op Fl f
 .Op Fl s
 .Op Fl c Ar core
 .Op Ar executable
@@ -61,6 +62,13 @@ The following options are available:
 .It Fl c
 Write the core file to the specified file instead of
 .Dq Pa core.<pid> .
+.It Fl f
+Dumps all the available segments, excluding only the malformed ones and
+un-dumpable ones. Differently from the default invocation, it also dumps
+device-mapped and sglist-mapped areas that may invalidate the state of
+some transactions. This flag, then, may be used very carefully, when the
+full behaviour of the application is full-understood and the fallouts can
+be easilly controlled.
 .It Fl s
 Stop the process while gathering the core image, and resume it
 when done.

Modified: head/usr.bin/gcore/gcore.c
==============================================================================
--- head/usr.bin/gcore/gcore.c	Wed Jul 14 16:31:22 2010	(r210062)
+++ head/usr.bin/gcore/gcore.c	Wed Jul 14 17:16:25 2010	(r210063)
@@ -71,7 +71,7 @@ __FBSDID("$FreeBSD$");
 #include <unistd.h>
 
 #include "extern.h"
-int sflag;
+int pflags;
 
 static void	killed(int);
 static void	usage(void) __dead2;
@@ -89,15 +89,18 @@ main(int argc, char *argv[])
 	struct dumpers **d, *dumper;
 	size_t len;
 
-	sflag = 0;
+	pflags = 0;
 	corefile = NULL;
-        while ((ch = getopt(argc, argv, "c:s")) != -1) {
+        while ((ch = getopt(argc, argv, "c:fs")) != -1) {
                 switch (ch) {
                 case 'c':
 			corefile = optarg;
                         break;
+		case 'f':
+			pflags |= PFLAGS_FULL;
+			break;
 		case 's':
-			sflag = 1;
+			pflags |= PFLAGS_RESUME;
 			break;
 		default:
 			usage();