diff -urpN -X dontdiff linux-2.6.0-test6.prev/fs/Kconfig linux-2.6.0-test6.cur/fs/Kconfig --- linux-2.6.0-test6.prev/fs/Kconfig Thu Oct 16 11:13:53 2003 +++ linux-2.6.0-test6.cur/fs/Kconfig Thu Oct 16 11:17:20 2003 @@ -899,8 +899,8 @@ config RELAYFS_FS an efficient mechanism for tools and facilities to relay large amounts of data from kernel space to user space. It's not useful on its own, and should only be enabled if other facilities that - need it are enabled, such as for example dynamic printk or the - Linux Trace Toolkit. + need it are enabled, such as for example klog or the Linux Trace + Toolkit. See for further information. @@ -911,6 +911,36 @@ config RELAYFS_FS module, say M here and read . If unsure, say N. + +config KLOG_CHANNEL + bool "Enable klog debugging support" + depends on RELAYFS_FS + help + If you say Y to this, a relayfs channel named klog will be created + in the root of the relayfs file system. You can write to the klog + channel using klog() or klog_raw() from within the kernel or + kernel modules, and read from the klog channel by mounting relayfs + and using read(2) to read from it (or using cat). If you're not + sure, say N. + +config KLOG_CHANNEL_AUTOENABLE + bool "Enable klog logging on startup" + depends on KLOG_CHANNEL + default y + help + If you say Y to this, the klog channel will be automatically enabled + on startup. Otherwise, to turn klog logging on, you need use + sysctl (kernel.klog_enabled). This option is used in cases where + you don't actually want the channel to be written to until it's + enabled. If you're not sure, say Y. + +config KLOG_CHANNEL_SHIFT + depends on KLOG_CHANNEL + int "klog debugging channel size (16 => 64KB, 22 => 4MB)" + range 16 22 + default 21 + help + Select klog debugging channel size as a power of 2. endmenu diff -urpN -X dontdiff linux-2.6.0-test6.prev/fs/relayfs/Makefile linux-2.6.0-test6.cur/fs/relayfs/Makefile --- linux-2.6.0-test6.prev/fs/relayfs/Makefile Thu Oct 16 11:13:53 2003 +++ linux-2.6.0-test6.cur/fs/relayfs/Makefile Thu Oct 16 11:17:20 2003 @@ -3,5 +3,6 @@ # obj-$(CONFIG_RELAYFS_FS) += relayfs.o +obj-$(CONFIG_KLOG_CHANNEL) += klog.o relayfs-objs := relay.o relay_lockless.o relay_locking.o inode.o diff -urpN -X dontdiff linux-2.6.0-test6.prev/fs/relayfs/inode.c linux-2.6.0-test6.cur/fs/relayfs/inode.c --- linux-2.6.0-test6.prev/fs/relayfs/inode.c Thu Oct 16 11:13:53 2003 +++ linux-2.6.0-test6.cur/fs/relayfs/inode.c Thu Oct 16 11:17:20 2003 @@ -551,10 +551,17 @@ static struct file_system_type relayfs_f .kill_sb = kill_litter_super, }; +extern int create_klog_channel(void); + static int __init init_relayfs_fs(void) { - return register_filesystem(&relayfs_fs_type); + int err = register_filesystem(&relayfs_fs_type); +#ifdef CONFIG_KLOG_CHANNEL + if (!err) + create_klog_channel(); +#endif + return err; } static void __exit diff -urpN -X dontdiff linux-2.6.0-test6.prev/fs/relayfs/klog.c linux-2.6.0-test6.cur/fs/relayfs/klog.c --- linux-2.6.0-test6.prev/fs/relayfs/klog.c Wed Dec 31 18:00:00 1969 +++ linux-2.6.0-test6.cur/fs/relayfs/klog.c Thu Oct 16 11:52:47 2003 @@ -0,0 +1,116 @@ +/* + * KLOG Generic Logging facility built upon the relayfs infrastructure + * + * Authors: Hubertus Franke (frankeh@us.ibm.com) + * Tom Zanussi (zanussi@us.ibm.com) + * + * Please direct all questions/comments to zanussi@us.ibm.com + * + * Copyright (C) 2003, IBM Corp + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#ifdef KLOG_CHANNEL_AUTOENABLE +int klog_enabled = 1; +#else +int klog_enabled = 0; +#endif +EXPORT_SYMBOL(klog_enabled); + +int klog_channel = -1; + +static char buf[NR_CPUS][KLOG_BUF_SIZE]; + +/** + * klog - write a formatted string into the klog channel + * @fmt: format string + * + * Returns number of bytes written, negative number on failure. + */ +int klog(const char *fmt, ...) +{ + va_list args; + int len, err; + char *cbuf; + unsigned long flags; + + if (!klog_enabled || klog_channel < 0) + return 0; + + local_irq_save(flags); + cbuf = buf[smp_processor_id()]; + + va_start(args, fmt); + len = vsnprintf(cbuf, KLOG_BUF_SIZE, fmt, args); + va_end(args); + + err = relay_write(klog_channel, cbuf, len, -1); + local_irq_restore(flags); + + return err; +} + +/** + * klog_raw - directly write into the klog channel + * @buf: buffer containing data to write + * @len: # bytes to write + * + * Returns number of bytes written, negative number on failure. + */ +int klog_raw(const char *buf,int len) +{ + int err = 0; + + if (klog_enabled && klog_channel >= 0) + err = relay_write(klog_channel, buf, len, -1); + + return err; +} + +/* internal - creates channel file /mnt/relay/klog */ +int create_klog_channel(void) +{ + u32 bufsize, nbufs; + + u32 channel_flags = RELAY_DELIVERY_PACKET | RELAY_USAGE_GLOBAL; + channel_flags |= RELAY_SCHEME_ANY | RELAY_TIMESTAMP_ANY; + + bufsize = 1 << (CONFIG_KLOG_CHANNEL_SHIFT - 2); /* size of sub-buffers */ + nbufs = 4; + + klog_channel = relay_open("klog", + bufsize, + nbufs, + channel_flags, + NULL, + 0, + 0, + 0, + 0, + 0); + + if (klog_channel < 0) + printk("klog channel creation failed, errcode: %d\n", klog_channel); + else + printk("klog channel created (%u bytes)\n", 1 << CONFIG_KLOG_CHANNEL_SHIFT); + + return klog_channel; +} + +EXPORT_SYMBOL(klog); +EXPORT_SYMBOL(klog_raw); diff -urpN -X dontdiff linux-2.6.0-test6.prev/include/linux/klog.h linux-2.6.0-test6.cur/include/linux/klog.h --- linux-2.6.0-test6.prev/include/linux/klog.h Wed Dec 31 18:00:00 1969 +++ linux-2.6.0-test6.cur/include/linux/klog.h Thu Oct 16 11:41:01 2003 @@ -0,0 +1,29 @@ +/* + * KLOG Generic Logging facility built upon the relayfs infrastructure + * + * Authors: Hubertus Frankeh (frankeh@us.ibm.com) + * Tom Zanussi (zanussi@us.ibm.com) + * + * Please direct all questions/comments to zanussi@us.ibm.com + * + * Copyright (C) 2003, IBM Corp + * + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#ifndef _LINUX_KLOG_H +#define _LINUX_KLOG_H + +extern int klog_channel; + +#define KLOG_BUF_SIZE (512) /* maximum size of formatting buffer for klog + * beyond which truncation will take place */ + +int klog(const char *fmt, ...); +int klog_raw(const char *buf,int len); + +#endif /* _LINUX_KLOG_H */ diff -urpN -X dontdiff linux-2.6.0-test6.prev/kernel/sysctl.c linux-2.6.0-test6.cur/kernel/sysctl.c --- linux-2.6.0-test6.prev/kernel/sysctl.c Sat Sep 27 19:50:09 2003 +++ linux-2.6.0-test6.cur/kernel/sysctl.c Thu Oct 16 11:17:20 2003 @@ -93,6 +93,7 @@ extern int pwrsw_enabled; extern int unaligned_enabled; #endif +extern int klog_enabled; #ifdef CONFIG_ARCH_S390 #ifdef CONFIG_MATHEMU extern int sysctl_ieee_emulation_warnings; @@ -577,6 +578,14 @@ static ctl_table kern_table[] = { .ctl_name = KERN_PANIC_ON_OOPS, .procname = "panic_on_oops", .data = &panic_on_oops, + .maxlen = sizeof(int), + .mode = 0644, + .proc_handler = &proc_dointvec, + }, + { + .ctl_name = 100, // just make up a number + .procname = "klog_enabled", + .data = &klog_enabled, .maxlen = sizeof(int), .mode = 0644, .proc_handler = &proc_dointvec,