dynamic debug: combine dprintk and dynamic printk

This patch combines Greg Bank's dprintk() work with the existing dynamic
printk patchset, we are now calling it 'dynamic debug'.

The new feature of this patchset is a richer /debugfs control file interface,
(an example output from my system is at the bottom), which allows fined grained
control over the the debug output. The output can be controlled by function,
file, module, format string, and line number.

for example, enabled all debug messages in module 'nf_conntrack':

echo -n 'module nf_conntrack +p' > /mnt/debugfs/dynamic_debug/control

to disable them:

echo -n 'module nf_conntrack -p' > /mnt/debugfs/dynamic_debug/control

A further explanation can be found in the documentation patch.

Signed-off-by: Greg Banks <gnb@sgi.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

1 files changed, 6 insertions, 9 deletions

diff --git a/include/asm-generic/vmlinux.lds.h b/include/asm-generic/vmlinux.lds.h
index c61fab1dd2f8..aca40b93bd28 100644
--- a/include/asm-generic/vmlinux.lds.h
+++ b/include/asm-generic/vmlinux.lds.h
@@ -80,6 +80,11 @@
         VMLINUX_SYMBOL(__start___tracepoints) = .;                      \
         *(__tracepoints)                                                \
         VMLINUX_SYMBOL(__stop___tracepoints) = .;                       \
+        /* implement dynamic printk debug */                            \
+        . = ALIGN(8);                                                   \
+        VMLINUX_SYMBOL(__start___verbose) = .;                          \
+        *(__verbose)                                                    \
+        VMLINUX_SYMBOL(__stop___verbose) = .;                           \
         LIKELY_PROFILE()                                                \
         BRANCH_PROFILE()
 
@@ -309,15 +314,7 @@
         CPU_DISCARD(init.data)                                          \
         CPU_DISCARD(init.rodata)                                        \
         MEM_DISCARD(init.data)                                          \
-        MEM_DISCARD(init.rodata)                                        \
-        /* implement dynamic printk debug */                            \
-        VMLINUX_SYMBOL(__start___verbose_strings) = .;                  \
-        *(__verbose_strings)                                            \
-        VMLINUX_SYMBOL(__stop___verbose_strings) = .;                   \
-        . = ALIGN(8);                                                   \
-        VMLINUX_SYMBOL(__start___verbose) = .;                          \
-        *(__verbose)                                                    \
-        VMLINUX_SYMBOL(__stop___verbose) = .;
+        MEM_DISCARD(init.rodata)
 
 #define INIT_TEXT                                                       \
         *(.init.text)                                                   \