[Crash-utility] [PATCH] search: Introduce -T option

[Aaron Tomlin]

Like the -t option, except consider only the "active" task
on each CPU and cannot be used on a live system or dump.
The -t and -T options are mutually exclusive.

Signed-off-by: Aaron Tomlin <atomlin at redhat.com>
---
 help.c   |  4 +++-
 memory.c | 52 ++++++++++++++++++++++++++++++++++++++++------------
 2 files changed, 43 insertions(+), 13 deletions(-)

diff --git a/help.c b/help.c
index 2d80202..5b3e89c 100644
--- a/help.c
+++ b/help.c
@@ -2862,7 +2862,7 @@ NULL
 char *help_search[] = {
 "search",
 "search memory",
-"[-s start] [ -[kKV] | -u | -p | -t ] [-e end | -l length] [-m mask]\n"
+"[-s start] [ -[kKV] | -u | -p | -t|-T ] [-e end | -l length] [-m mask]\n"
 "         [-x count] -[cwh] [value | (expression) | symbol | string] ...",
 "  This command searches for a given value within a range of user virtual, kernel",
 "  virtual, or physical memory space.  If no end nor length value is entered, ",
@@ -2893,6 +2893,8 @@ char *help_search[] = {
 "          -t  Search only the kernel stack pages of every task.  If one or more",
 "              matches are found in a task's kernel stack, precede the output",
 "              with a task-identifying header.",
+"          -T  Same as -t, except only the active task(s) are considered.",
+"              This option cannot be used on a live system or dump.",
 "      -e end  Stop the search at this hexadecimal user or kernel virtual",
 "              address, kernel symbol, or physical address.  The end address",
 "              must be appropriate for the memory type specified.",
diff --git a/memory.c b/memory.c
index 8efe0b2..573b670 100644
--- a/memory.c
+++ b/memory.c
@@ -227,6 +227,7 @@ static ulonglong search_ushort_p(ulong *, ulonglong, int, struct searchinfo *);
 static ulonglong search_chars_p(ulong *, ulonglong, int, struct searchinfo *);
 static void search_virtual(struct searchinfo *);
 static void search_physical(struct searchinfo *);
+static void prepare_searchinfo_for_task_search(struct searchinfo *, struct task_context *);
 static int next_upage(struct task_context *, ulong, ulong *);
 static int next_kpage(ulong, ulong *);
 static int next_physpage(ulonglong, ulonglong *);
@@ -13864,7 +13865,15 @@ generic_get_kvaddr_ranges(struct vaddr_range *rp)
 	return cnt;
 }
 
-
+static void
+prepare_searchinfo_for_task_search(struct searchinfo *si, struct task_context *tc)
+{
+	si->tasks_found = 0;
+	si->vaddr_start = GET_STACKBASE(tc->task); 
+	si->vaddr_end = GET_STACKTOP(tc->task);
+	si->task_context = tc;
+	si->do_task_header = TRUE;
+}
 /*
  *  Search for a given value between a starting and ending address range,
  *  applying an optional mask for "don't care" bits.  As an alternative
@@ -13882,7 +13891,7 @@ cmd_search(void)
 	ulong value, mask, len;
 	ulong uvaddr_start, uvaddr_end;
 	ulong kvaddr_start, kvaddr_end, range_end;
-	int sflag, Kflag, Vflag, pflag, tflag;
+	int sflag, Kflag, Vflag, pflag, Tflag, tflag;
 	struct searchinfo searchinfo;
 	struct syment *sp;
 	struct node_table *nt;
@@ -13896,7 +13905,7 @@ cmd_search(void)
 
 	context = max = 0;
 	start = end = 0;
-	value = mask = sflag = pflag = Kflag = Vflag = memtype = len = tflag = 0;
+	value = mask = sflag = pflag = Kflag = Vflag = memtype = len = Tflag = tflag = 0;
 	kvaddr_start = kvaddr_end = 0;
 	uvaddr_start = UNINITIALIZED;
 	uvaddr_end = COMMON_VADDR_SPACE() ? (ulong)(-1) : machdep->kvbase;
@@ -13933,7 +13942,7 @@ cmd_search(void)
 
 	searchinfo.mode = SEARCH_ULONG;	/* default search */
 
-        while ((c = getopt(argcnt, args, "tl:ukKVps:e:v:m:hwcx:")) != EOF) {
+        while ((c = getopt(argcnt, args, "Ttl:ukKVps:e:v:m:hwcx:")) != EOF) {
                 switch(c)
                 {
 		case 'u':
@@ -14038,6 +14047,10 @@ cmd_search(void)
 			context = dtoi(optarg, FAULT_ON_ERROR, NULL);
 			break;
 
+		case 'T':
+			Tflag++;
+			break;
+
 		case 't':
 			if (XEN_HYPER_MODE())
 				error(FATAL, 
@@ -14052,10 +14065,20 @@ cmd_search(void)
                 }
         }
 
-	if (tflag && (memtype || start || end || len)) 
+	if ((tflag || Tflag) && (memtype || start || end || len)) 
+		error(FATAL, 
+		    "-%s option cannot be used with other "
+		    "memory-selection options\n",
+		    tflag ? "t" : "T");
+
+	if (Tflag && LIVE())
+		error(FATAL, 
+		    "-T option cannot be used on a live "
+		    "system or live dump\n");
+
+	if (tflag && Tflag)
 		error(FATAL, 
-		    "-t option cannot be used with other "
-		    "memory-selection options\n");
+		"-t and -T options are mutually exclusive\n");
 
 	if (XEN_HYPER_MODE()) {
 		memtype = KVADDR;
@@ -14328,14 +14351,19 @@ cmd_search(void)
 			break;
 		}
 
+		if (Tflag) {
+			for (c = 0; c < NR_CPUS; c++)
+				if ((tc = task_to_context(tt->panic_threads[c]))) {
+					prepare_searchinfo_for_task_search(&searchinfo, tc);
+					search_virtual(&searchinfo);
+				}
+			break;
+		}
+
 		if (tflag) {
-			searchinfo.tasks_found = 0;
 			tc = FIRST_CONTEXT();
 			for (i = 0; i < RUNNING_TASKS(); i++, tc++) {
-				searchinfo.vaddr_start = GET_STACKBASE(tc->task); 
-				searchinfo.vaddr_end = GET_STACKTOP(tc->task);
-				searchinfo.task_context = tc;
-				searchinfo.do_task_header = TRUE;
+				prepare_searchinfo_for_task_search(&searchinfo, tc);
 				search_virtual(&searchinfo);
 			}
 			break;
-- 
2.9.4