From: Martin Schwidefsky <schwidefsky@de.ibm.com>
From: Michael Holzheu <holzheu@de.ibm.com>

Introduce a new family of printk macros which prefixes each kmsg message
with a component name and allows to tag the message with a 24 bit hash of
the message text. The kmsg component name is defined per source file with
the KMSG_COMPONENT macro.

If the message hash will be printed to the console / syslog at all depends
on CONFIG_MSG_IDS. If it is "n" then a kmsg_xxx call is just another
printk wrapper. These macros are intended to be used uniformly in the
s390 architecture and the s390 device drivers.

Signed-off-by: Michael Holzheu <holzheu@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---

 arch/s390/Kconfig    |    9 ++++++++
 include/linux/kmsg.h |   54 +++++++++++++++++++++++++++++++++++++++++++++++++++
 kernel/printk.c      |   24 ++++++++++++++++++++++
 3 files changed, 87 insertions(+)

Index: quilt-2.6/arch/s390/Kconfig
===================================================================
--- quilt-2.6.orig/arch/s390/Kconfig
+++ quilt-2.6/arch/s390/Kconfig
@@ -571,6 +571,15 @@ bool "s390 guest support (EXPERIMENTAL)"
 	select VIRTIO_CONSOLE
 	help
 	  Select this option if you want to run the kernel under s390 linux
+
+config KMSG_IDS
+	bool "Kernel message numbers"
+	default y
+	help
+	  Select this option if you want to include a message number to the
+	  prefix for kernel messages issued by the s390 architecture and
+	  driver code. See "Documentation/s390/kmsg.txt" for more details.
+
 endmenu
 
 source "net/Kconfig"
Index: quilt-2.6/include/linux/kmsg.h
===================================================================
--- /dev/null
+++ quilt-2.6/include/linux/kmsg.h
@@ -0,0 +1,54 @@
+#ifndef _LINUX_KMSG_H
+#define _LINUX_KMSG_H
+
+int kmsg_printk(char *prefix, char *fmt, ...);
+
+#if defined(__KMSG_CHECKER)
+#define KMSG_ID KMSG_COMPONENT ".%06x"
+#define KMSG_FMT(fmt) _$_(fmt)_$_
+#define kmsg_printk __KMSG_CHECK
+#elif defined(CONFIG_KMSG_IDS)
+#define KMSG_ID KMSG_COMPONENT ".%06x"
+#define KMSG_FMT(fmt) fmt
+#else /* !defined(CONFIG_KMSG_IDS) */
+#define KMSG_ID KMSG_COMPONENT
+#define KMSG_FMT(fmt) fmt
+#define kmsg_printk(prefix, fmt, ...) printk(prefix # fmt, ##__VA_ARGS__)
+#endif
+
+#define kmsg_alert(fmt, ...) \
+	kmsg_printk(KERN_ALERT KMSG_ID ": ", KMSG_FMT(fmt), ##__VA_ARGS__)
+
+#define kmsg_err(fmt, ...) \
+	kmsg_printk(KERN_ERR KMSG_ID ": ", KMSG_FMT(fmt), ##__VA_ARGS__)
+
+#define kmsg_warn(fmt, ...) \
+	kmsg_printk(KERN_WARNING KMSG_ID ": ", KMSG_FMT(fmt), ##__VA_ARGS__)
+
+#define kmsg_info(fmt, ...) \
+	kmsg_printk(KERN_INFO KMSG_ID ": ", KMSG_FMT(fmt), ##__VA_ARGS__)
+
+#define kmsg_notice(fmt, ...) \
+	kmsg_printk(KERN_NOTICE KMSG_ID ": ", KMSG_FMT(fmt), ##__VA_ARGS__)
+
+#define kmsg_dev_alert(dev, fmt, ...) \
+	kmsg_printk(KERN_ALERT KMSG_ID ":%s: ", KMSG_FMT(fmt), \
+		    dev_name(dev), ##__VA_ARGS__)
+
+#define kmsg_dev_err(dev, fmt, ...) \
+	kmsg_printk(KERN_ERR KMSG_ID ":%s: ", KMSG_FMT(fmt), \
+		    dev_name(dev), ##__VA_ARGS__)
+
+#define kmsg_dev_warn(dev, fmt, ...) \
+	kmsg_printk(KERN_WARNING KMSG_ID ":%s: ", KMSG_FMT(fmt), \
+		    dev_name(dev), ##__VA_ARGS__)
+
+#define kmsg_dev_info(dev, fmt, ...) \
+	kmsg_printk(KERN_INFO KMSG_ID ":%s: ", KMSG_FMT(fmt), \
+		    dev_name(dev), ##__VA_ARGS__)
+
+#define kmsg_dev_notice(dev, fmt, ...) \
+	kmsg_printk(KERN_NOTICE KMSG_ID ":%s: ", KMSG_FMT(fmt), \
+		    dev_name(dev), ##__VA_ARGS__)
+
+#endif /* _LINUX_KMSG_H */
Index: quilt-2.6/kernel/printk.c
===================================================================
--- quilt-2.6.orig/kernel/printk.c
+++ quilt-2.6/kernel/printk.c
@@ -32,6 +32,7 @@
 #include <linux/security.h>
 #include <linux/bootmem.h>
 #include <linux/syscalls.h>
+#include <linux/jhash.h>
 
 #include <asm/uaccess.h>
 
@@ -1343,3 +1344,26 @@ bool printk_timed_ratelimit(unsigned lon
 }
 EXPORT_SYMBOL(printk_timed_ratelimit);
 #endif
+
+#if defined CONFIG_PRINTK && defined CONFIG_KMSG_IDS
+
+/**
+ * kmsg_printk - print a kernel message with a message id
+ * @fmt: format string
+ * @hfmt: revelant part of the format string included in the hash
+ */
+asmlinkage int kmsg_printk(const char *prefix, const char *fmt, ...)
+{
+	va_list args;
+	int r;
+
+	r = printk(prefix, jhash(fmt, strlen(fmt), 0) & 0xffffff);
+	va_start(args, fmt);
+	r += vprintk(fmt, args);
+	va_end(args);
+
+	return r;
+}
+EXPORT_SYMBOL(kmsg_printk);
+
+#endif

-- 
blue skies,
   Martin.

"Reality continues to ruin my life." - Calvin.

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/