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-rw-r--r--Documentation/s390/s390dbf.txt12
1 files changed, 6 insertions, 6 deletions
diff --git a/Documentation/s390/s390dbf.txt b/Documentation/s390/s390dbf.txt
index e321a8ed2a2d..000230cd26db 100644
--- a/Documentation/s390/s390dbf.txt
+++ b/Documentation/s390/s390dbf.txt
@@ -11,7 +11,7 @@ where log records can be stored efficiently in memory, where each component
11(e.g. device drivers) can have one separate debug log. 11(e.g. device drivers) can have one separate debug log.
12One purpose of this is to inspect the debug logs after a production system crash 12One purpose of this is to inspect the debug logs after a production system crash
13in order to analyze the reason for the crash. 13in order to analyze the reason for the crash.
14If the system still runs but only a subcomponent which uses dbf failes, 14If the system still runs but only a subcomponent which uses dbf fails,
15it is possible to look at the debug logs on a live system via the Linux 15it is possible to look at the debug logs on a live system via the Linux
16debugfs filesystem. 16debugfs filesystem.
17The debug feature may also very useful for kernel and driver development. 17The debug feature may also very useful for kernel and driver development.
@@ -65,7 +65,7 @@ Predefined views for hex/ascii, sprintf and raw binary data are provided.
65It is also possible to define other views. The content of 65It is also possible to define other views. The content of
66a view can be inspected simply by reading the corresponding debugfs file. 66a view can be inspected simply by reading the corresponding debugfs file.
67 67
68All debug logs have an an actual debug level (range from 0 to 6). 68All debug logs have an actual debug level (range from 0 to 6).
69The default level is 3. Event and Exception functions have a 'level' 69The default level is 3. Event and Exception functions have a 'level'
70parameter. Only debug entries with a level that is lower or equal 70parameter. Only debug entries with a level that is lower or equal
71than the actual level are written to the log. This means, when 71than the actual level are written to the log. This means, when
@@ -83,8 +83,8 @@ Example:
83It is also possible to deactivate the debug feature globally for every 83It is also possible to deactivate the debug feature globally for every
84debug log. You can change the behavior using 2 sysctl parameters in 84debug log. You can change the behavior using 2 sysctl parameters in
85/proc/sys/s390dbf: 85/proc/sys/s390dbf:
86There are currently 2 possible triggers, which stop the debug feature 86There are currently 2 possible triggers, which stop the debug feature
87globally. The first possbility is to use the "debug_active" sysctl. If 87globally. The first possibility is to use the "debug_active" sysctl. If
88set to 1 the debug feature is running. If "debug_active" is set to 0 the 88set to 1 the debug feature is running. If "debug_active" is set to 0 the
89debug feature is turned off. 89debug feature is turned off.
90The second trigger which stops the debug feature is an kernel oops. 90The second trigger which stops the debug feature is an kernel oops.
@@ -468,7 +468,7 @@ The hex_ascii view shows the data field in hex and ascii representation
468The raw view returns a bytestream as the debug areas are stored in memory. 468The raw view returns a bytestream as the debug areas are stored in memory.
469 469
470The sprintf view formats the debug entries in the same way as the sprintf 470The sprintf view formats the debug entries in the same way as the sprintf
471function would do. The sprintf event/expection functions write to the 471function would do. The sprintf event/exception functions write to the
472debug entry a pointer to the format string (size = sizeof(long)) 472debug entry a pointer to the format string (size = sizeof(long))
473and for each vararg a long value. So e.g. for a debug entry with a format 473and for each vararg a long value. So e.g. for a debug entry with a format
474string plus two varargs one would need to allocate a (3 * sizeof(long)) 474string plus two varargs one would need to allocate a (3 * sizeof(long))
@@ -556,7 +556,7 @@ The input_proc can be used to implement functionality when it is written to
556the view (e.g. like with 'echo "0" > /sys/kernel/debug/s390dbf/dasd/level). 556the view (e.g. like with 'echo "0" > /sys/kernel/debug/s390dbf/dasd/level).
557 557
558For header_proc there can be used the default function 558For header_proc there can be used the default function
559debug_dflt_header_fn() which is defined in in debug.h. 559debug_dflt_header_fn() which is defined in debug.h.
560and which produces the same header output as the predefined views. 560and which produces the same header output as the predefined views.
561E.g: 561E.g:
56200 00964419409:440761 2 - 00 88023ec 56200 00964419409:440761 2 - 00 88023ec