[Crash-utility] [PATCH 5/7] bt: get remote live registers if possible.

[Don Slutz]

From: Don Slutz <dslutz at verizon.com>

Signed-off-by: Don Slutz <dslutz at verizon.com>
---
 defs.h   |  1 +
 kernel.c | 22 ++++++++++++++++++++--
 remote.c | 57 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 78 insertions(+), 2 deletions(-)

diff --git a/defs.h b/defs.h
index 94ba495..adbfadc 100755
--- a/defs.h
+++ b/defs.h
@@ -5528,6 +5528,7 @@ void dump_sockets_workhorse(ulong, ulong, struct reference *);
 int is_remote_daemon(char *);
 physaddr_t get_remote_phys_base(physaddr_t, physaddr_t);
 physaddr_t remote_vtop(int, physaddr_t);
+int get_remote_regs(struct bt_info *, ulong *, ulong *);
 void remote_fd_init(void);
 int get_remote_file(struct remote_file *);
 uint remote_page_size(void);
diff --git a/kernel.c b/kernel.c
index 7b451c9..ab50361 100755
--- a/kernel.c
+++ b/kernel.c
@@ -1116,6 +1116,9 @@ non_matching_kernel(void)
                 if (REMOTE_DUMPFILE())
                         fprintf(fp, "%s@%s  (remote dumpfile)\n",
                                 pc->server_memsrc, pc->server);
+		else if (REMOTE_ACTIVE())
+			fprintf(fp, "%s@%s  (remote system)\n",
+				pc->server_memsrc, pc->server);
                 else {
                         if (dumpfile_is_split())
                                 show_split_dumpfiles();
@@ -2408,7 +2411,7 @@ back_trace(struct bt_info *bt)
 		    (BT_KSTACKP|BT_TEXT_SYMBOLS|BT_TEXT_SYMBOLS_ALL)))
 			fprintf(fp, "(active)\n");
 
-		if (!(bt->flags & (BT_TEXT_SYMBOLS|BT_TEXT_SYMBOLS_ALL)))
+		if (!(bt->flags & (BT_TEXT_SYMBOLS|BT_TEXT_SYMBOLS_ALL) || REMOTE_ACTIVE()))
 			return;
  	}
 
@@ -2486,7 +2489,10 @@ back_trace(struct bt_info *bt)
 		get_xendump_regs(bt, &eip, &esp);
 	else if (SADUMP_DUMPFILE())
 		get_sadump_regs(bt, &eip, &esp);
-        else
+        else if (REMOTE_ACTIVE() && ((bt->task == tt->this_task) || is_task_active(bt->task))) {
+		if (get_remote_regs(bt, &eip, &esp))
+			machdep->get_stack_frame(bt, &eip, &esp);
+	} else
                 machdep->get_stack_frame(bt, &eip, &esp);
 
 	if (bt->flags & BT_KSTACKP) {
@@ -9210,3 +9216,15 @@ dump_variable_length_record(void)
 
 	hq_close();
 }
+
+/*
+ * Specify Emacs local variables so the formating
+ * of the code stays the same.
+ *
+ * Local variables:
+ * mode: C
+ * c-set-style: "BSD"
+ * c-basic-offset: 8
+ * indent-tabs-mode: t
+ * End:
+ */
diff --git a/remote.c b/remote.c
index 2186af9..4b0388d 100755
--- a/remote.c
+++ b/remote.c
@@ -2382,6 +2382,63 @@ remote_vtop(int cpu, physaddr_t virt_addr)
 }
 
 /*
+ *  Get a copy of the daemon machine cpu regs.
+ */
+int
+get_remote_regs(struct bt_info *bt, ulong *eip, ulong *esp)
+{
+	char sendbuf[BUFSIZE];
+	char recvbuf[BUFSIZE];
+	char *p1, *p2, *p3, *p4, *p5, *p6;
+	int errflag;
+	ulong value;
+
+	if (!rc->remoteType[0])
+		return 1;       /* Not a special remote. */
+
+	*eip = 0;
+	*esp = 0;
+
+	BZERO(sendbuf, BUFSIZE);
+	BZERO(recvbuf, BUFSIZE);
+	sprintf(sendbuf, "FETCH_LIVE_IP_SP_BP %d", bt->tc->processor);
+	if (remote_tcp_write_string(pc->sockfd, sendbuf))
+		return 1;
+	errflag = remote_tcp_read_string(pc->sockfd, recvbuf, BUFSIZE-1, pc->flags2 & REMOTE_NIL);
+	if (errflag <= 0)
+		return 1;
+
+	if (CRASHDEBUG(1))
+		fprintf(fp, "get_remote_regs(cpu=%d): [%s]\n",
+			bt->tc->processor, recvbuf);
+
+	if (strstr(recvbuf, "<FAIL>")) {
+		error(INFO, "get_remote_regs for CPU %d\n", bt->tc->processor);
+		return 1;
+	}
+	p1 = strtok(recvbuf, " ");  /* FETCH_LIVE_IP_SP_BP */
+	p1 = strtok(NULL, " ");     /* cpu */
+	p1 = strtok(NULL, ":");     /* cs */
+	p2 = strtok(NULL, " ");     /* ip */
+	p3 = strtok(NULL, ":");     /* ss */
+	p4 = strtok(NULL, " ");     /* sp */
+	p5 = strtok(NULL, " ");     /* bp */
+
+	errflag = 0;
+	value = htol(p2, RETURN_ON_ERROR|QUIET, &errflag);
+	if (!errflag) {
+		*eip = value;
+	}
+
+	errflag = 0;
+	value = htol(p4, RETURN_ON_ERROR|QUIET, &errflag);
+	if (!errflag) {
+		*esp = value;
+	}
+	return 0;
+}
+
+/*
  *
  *   Set up the file descriptors and file name strings if they haven't
  *   been set up before:
-- 
1.8.4