diff options
Diffstat (limited to 'Documentation/dynamic-debug-howto.txt')
-rw-r--r-- | Documentation/dynamic-debug-howto.txt | 30 |
1 files changed, 12 insertions, 18 deletions
diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt index f959909d7154..74e6c7782678 100644 --- a/Documentation/dynamic-debug-howto.txt +++ b/Documentation/dynamic-debug-howto.txt @@ -12,7 +12,7 @@ dynamically enabled per-callsite. Dynamic debug has even more useful features: * Simple query language allows turning on and off debugging statements by - matching any combination of: + matching any combination of 0 or 1 of: - source filename - function name @@ -79,31 +79,24 @@ Command Language Reference ========================== At the lexical level, a command comprises a sequence of words separated -by whitespace characters. Note that newlines are treated as word -separators and do *not* end a command or allow multiple commands to -be done together. So these are all equivalent: +by spaces or tabs. So these are all equivalent: nullarbor:~ # echo -c 'file svcsock.c line 1603 +p' > <debugfs>/dynamic_debug/control nullarbor:~ # echo -c ' file svcsock.c line 1603 +p ' > <debugfs>/dynamic_debug/control -nullarbor:~ # echo -c 'file svcsock.c\nline 1603 +p' > - <debugfs>/dynamic_debug/control nullarbor:~ # echo -n 'file svcsock.c line 1603 +p' > <debugfs>/dynamic_debug/control -Commands are bounded by a write() system call. If you want to do -multiple commands you need to do a separate "echo" for each, like: +Command submissions are bounded by a write() system call. +Multiple commands can be written together, separated by ';' or '\n'. -nullarbor:~ # echo 'file svcsock.c line 1603 +p' > /proc/dprintk ;\ -> echo 'file svcsock.c line 1563 +p' > /proc/dprintk + ~# echo "func pnpacpi_get_resources +p; func pnp_assign_mem +p" \ + > <debugfs>/dynamic_debug/control -or even like: +If your query set is big, you can batch them too: -nullarbor:~ # ( -> echo 'file svcsock.c line 1603 +p' ;\ -> echo 'file svcsock.c line 1563 +p' ;\ -> ) > /proc/dprintk + ~# cat query-batch-file > <debugfs>/dynamic_debug/control At the syntactical level, a command comprises a sequence of match specifications, followed by a flags change specification. @@ -144,11 +137,12 @@ func func svc_tcp_accept file - The given string is compared against either the full - pathname or the basename of the source file of each - callsite. Examples: + The given string is compared against either the full pathname, the + src-root relative pathname, or the basename of the source file of + each callsite. Examples: file svcsock.c + file kernel/freezer.c file /usr/src/packages/BUILD/sgi-enhancednfs-1.4/default/net/sunrpc/svcsock.c module |