rpms/kernel/devel xen-printf-rate-limit.patch, NONE, 1.1 kernel-2.6.spec, 1.2681, 1.2682

[fedora-cvs-commits at redhat.com]

Author: quintela

Update of /cvs/dist/rpms/kernel/devel
In directory cvs.devel.redhat.com:/tmp/cvs-serv30812

Modified Files:
	kernel-2.6.spec 
Added Files:
	xen-printf-rate-limit.patch 
Log Message:
xen printf rate limit patch (rostedt)

xen-printf-rate-limit.patch:
 arch/x86/mm.c          |   10 ++++++---
 drivers/char/console.c |   50 +++++++++++++++++++++++++++++++++++++++++++++++++
 include/xen/lib.h      |    3 ++
 3 files changed, 60 insertions(+), 3 deletions(-)

--- NEW FILE xen-printf-rate-limit.patch ---
Index: xen/arch/x86/mm.c
===================================================================
--- xen.orig/arch/x86/mm.c
+++ xen/arch/x86/mm.c
@@ -109,9 +109,13 @@
 #include <public/memory.h>
 
 #ifdef VERBOSE
-#define MEM_LOG(_f, _a...)                                  \
-  printk("DOM%u: (file=mm.c, line=%d) " _f "\n",            \
-         current->domain->domain_id , __LINE__ , ## _a )
+#define MEM_LOG(_f, _a...)                                          \
+    do {                                                            \
+        if (printk_ratelimit()) {                                   \
+            printk("DOM%u: (file=mm.c, line=%d) " _f "\n",          \
+                   current->domain->domain_id , __LINE__ , ## _a ); \
+                }                                                   \
+    } while (0)
 #else
 #define MEM_LOG(_f, _a...) ((void)0)
 #endif
Index: xen/drivers/char/console.c
===================================================================
--- xen.orig/drivers/char/console.c
+++ xen/drivers/char/console.c
@@ -4,6 +4,10 @@
  * Emergency console I/O for Xen and the domain-0 guest OS.
  * 
  * Copyright (c) 2002-2004, K A Fraser.
+ *
+ * Added printf_ratelimit
+ *     Taken from Linux - Author: Andy Kleen (net_ratelimit)
+ *     Ported to Xen - Steven Rostedt - Red Hat
  */
 
 #include <stdarg.h>
@@ -420,6 +424,52 @@ int console_getc(void)
     return serial_getc(sercon_handle);
 }
 
+/*
+ * printk rate limiting, lifted from Linux.
+ *
+ * This enforces a rate limit: not more than one kernel message
+ * every printf_ratelimit_jiffies.
+ */
+int __printf_ratelimit(int ratelimit_jiffies, int ratelimit_burst)
+{
+	static DEFINE_SPINLOCK(ratelimit_lock);
+	static unsigned long toks = 10 * 5 * HZ;
+	static unsigned long last_msg;
+	static int missed;
+	unsigned long flags;
+	unsigned long now = jiffies;
+
+	spin_lock_irqsave(&ratelimit_lock, flags);
+	toks += now - last_msg;
+	last_msg = now;
+	if (toks > (ratelimit_burst * ratelimit_jiffies))
+		toks = ratelimit_burst * ratelimit_jiffies;
+	if (toks >= ratelimit_jiffies) {
+		int lost = missed;
+
+		missed = 0;
+		toks -= ratelimit_jiffies;
+		spin_unlock_irqrestore(&ratelimit_lock, flags);
+		if (lost)
+			printk("printk: %d messages suppressed.\n", lost);
+		return 1;
+	}
+	missed++;
+	spin_unlock_irqrestore(&ratelimit_lock, flags);
+	return 0;
+}
+
+/* minimum time in jiffies between messages */
+int printf_ratelimit_jiffies = 5 * HZ;
+
+/* number of messages we send before ratelimiting */
+int printf_ratelimit_burst = 10;
+
+int printf_ratelimit(void)
+{
+	return __printf_ratelimit(printf_ratelimit_jiffies,
+				printf_ratelimit_burst);
+}
 
 /*
  * **************************************************************
Index: xen/include/xen/lib.h
===================================================================
--- xen.orig/include/xen/lib.h
+++ xen/include/xen/lib.h
@@ -52,8 +52,11 @@ extern void debugtrace_printk(const char
 /* Allows us to use '%p' as general-purpose machine-word format char. */
 #define _p(_x) ((void *)(unsigned long)(_x))
 #define printk(_f , _a...) printf( _f , ## _a )
+#define printk_ratelimit() printf_ratelimit()
 extern void printf(const char *format, ...)
     __attribute__ ((format (printf, 1, 2)));
+extern int __printf_ratelimit(int ratelimit_jiffies, int ratelimit_burst);
+extern int printf_ratelimit(void);
 extern void panic(const char *format, ...)
     __attribute__ ((format (printf, 1, 2)));
 extern long vm_assist(struct domain *, unsigned int, unsigned int);


Index: kernel-2.6.spec
===================================================================
RCS file: /cvs/dist/rpms/kernel/devel/kernel-2.6.spec,v
retrieving revision 1.2681
retrieving revision 1.2682
diff -u -r1.2681 -r1.2682
--- kernel-2.6.spec	20 Sep 2006 14:48:29 -0000	1.2681
+++ kernel-2.6.spec	20 Sep 2006 14:55:07 -0000	1.2682
@@ -526,6 +526,7 @@
 Patch10000: linux-2.6-compile-fixes.patch
 
 # Xen hypervisor patches (20000+)
+Patch20000: xen-printf-rate-limit.patch
 
 # END OF PATCH DEFINITIONS
 
@@ -1189,6 +1190,7 @@
 %setup -D -T -q -n %{name}-%{version} -a1
 cd xen
 # Any necessary hypervisor patches go here
+%patch20000 -p1
 %endif
 
 
@@ -1899,6 +1901,7 @@
 
 %changelog
 * Wed Sep 20 2006 Juan Quintela <quintela at redhat.com>
+- xen HV printf rate limit (rostedt).
 - xen HV update to xen-unstable cset11540:9837ff37e354
 - xen-update:
   * linux-2.6 changeset:   34294:dc1d277d06e0