Merge branch 'poll' into staging/for_v3.4

* poll: (5970 commits)
  poll: add poll_requested_events() and poll_does_not_wait() functions
  crc32: select an algorithm via Kconfig
  crc32: add self-test code for crc32c
  crypto: crc32c should use library implementation
  crc32: bolt on crc32c
  crc32: add note about this patchset to crc32.c
  crc32: optimize loop counter for x86
  crc32: add slice-by-8 algorithm to existing code
  crc32: make CRC_*_BITS definition correspond to actual bit counts
  crc32: fix mixing of endian-specific types
  crc32: miscellaneous cleanups
  crc32: simplify unit test code
  crc32: move long comment about crc32 fundamentals to Documentation/
  crc32: remove two instances of trailing whitespaces
  checkpatch: check for quoted strings broken across lines
  checkpatch: whitespace - add/remove blank lines
  checkpatch: warn on use of yield()
  checkpatch: add --strict tests for braces, comments and casts
  checkpatch: add [] to type extensions
  checkpatch: high precedence operators do not require additional parentheses in #defines
  ...

1 files changed, 31 insertions, 9 deletions

diff --git a/arch/s390/kernel/debug.c b/arch/s390/kernel/debug.c
index 6848828b962e..19e5e9eba546 100644
--- a/arch/s390/kernel/debug.c
+++ b/arch/s390/kernel/debug.c
@@ -2,8 +2,8 @@
  *  arch/s390/kernel/debug.c
  *   S/390 debug facility
  *
- *    Copyright (C) 1999, 2000 IBM Deutschland Entwicklung GmbH,
- *                             IBM Corporation
+ *    Copyright IBM Corp. 1999, 2012
+ *
  *    Author(s): Michael Holzheu (holzheu@de.ibm.com),
  *               Holger Smolinski (Holger.Smolinski@de.ibm.com)
  *
@@ -167,6 +167,7 @@ static debug_info_t *debug_area_last = NULL;
 static DEFINE_MUTEX(debug_mutex);
 
 static int initialized;
+static int debug_critical;
 
 static const struct file_operations debug_file_ops = {
 	.owner   = THIS_MODULE,
@@ -932,6 +933,11 @@ debug_stop_all(void)
 }
 
 
+void debug_set_critical(void)
+{
+	debug_critical = 1;
+}
+
 /*
  * debug_event_common:
  * - write debug entry with given size
@@ -945,7 +951,11 @@ debug_event_common(debug_info_t * id, int level, const void *buf, int len)
 
 	if (!debug_active || !id->areas)
 		return NULL;
-	spin_lock_irqsave(&id->lock, flags);
+	if (debug_critical) {
+		if (!spin_trylock_irqsave(&id->lock, flags))
+			return NULL;
+	} else
+		spin_lock_irqsave(&id->lock, flags);
 	active = get_active_entry(id);
 	memset(DEBUG_DATA(active), 0, id->buf_size);
 	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
@@ -968,7 +978,11 @@ debug_entry_t
 
 	if (!debug_active || !id->areas)
 		return NULL;
-	spin_lock_irqsave(&id->lock, flags);
+	if (debug_critical) {
+		if (!spin_trylock_irqsave(&id->lock, flags))
+			return NULL;
+	} else
+		spin_lock_irqsave(&id->lock, flags);
 	active = get_active_entry(id);
 	memset(DEBUG_DATA(active), 0, id->buf_size);
 	memcpy(DEBUG_DATA(active), buf, min(len, id->buf_size));
@@ -1013,7 +1027,11 @@ debug_sprintf_event(debug_info_t* id, int level,char *string,...)
 		return NULL;
 	numargs=debug_count_numargs(string);
 
-	spin_lock_irqsave(&id->lock, flags);
+	if (debug_critical) {
+		if (!spin_trylock_irqsave(&id->lock, flags))
+			return NULL;
+	} else
+		spin_lock_irqsave(&id->lock, flags);
 	active = get_active_entry(id);
 	curr_event=(debug_sprintf_entry_t *) DEBUG_DATA(active);
 	va_start(ap,string);
@@ -1047,7 +1065,11 @@ debug_sprintf_exception(debug_info_t* id, int level,char *string,...)
 
 	numargs=debug_count_numargs(string);
 
-	spin_lock_irqsave(&id->lock, flags);
+	if (debug_critical) {
+		if (!spin_trylock_irqsave(&id->lock, flags))
+			return NULL;
+	} else
+		spin_lock_irqsave(&id->lock, flags);
 	active = get_active_entry(id);
 	curr_event=(debug_sprintf_entry_t *)DEBUG_DATA(active);
 	va_start(ap,string);
@@ -1428,10 +1450,10 @@ debug_hex_ascii_format_fn(debug_info_t * id, struct debug_view *view,
 	rc += sprintf(out_buf + rc, "| ");
 	for (i = 0; i < id->buf_size; i++) {
 		unsigned char c = in_buf[i];
-		if (!isprint(c))
-			rc += sprintf(out_buf + rc, ".");
-		else
+		if (isascii(c) && isprint(c))
 			rc += sprintf(out_buf + rc, "%c", c);
+		else
+			rc += sprintf(out_buf + rc, ".");
 	}
 	rc += sprintf(out_buf + rc, "\n");
 	return rc;