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authorIngo Molnar <mingo@kernel.org>2012-04-13 09:50:21 +0200
committerIngo Molnar <mingo@kernel.org>2012-04-13 09:50:21 +0200
commit659c36fcda403013a01b85da07cf2d9711e6d6c7 (patch)
treeece2e7d0e2c19ea5a3d0ec172ad0b81a8a19021d /Documentation/dynamic-debug-howto.txt
parentMerge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/... (diff)
parentperf record: Use sw counter only if hw pmu is not detected (diff)
downloadlinux-659c36fcda403013a01b85da07cf2d9711e6d6c7.tar.xz
linux-659c36fcda403013a01b85da07cf2d9711e6d6c7.zip
Merge tag 'perf-core-for-mingo' of git://git.kernel.org/pub/scm/linux/kernel/git/acme/linux into perf/core
Fixes and improvements for perf/core: . Overhaul the tools/ makefiles, gluing them to the top level Makefile, from Borislav Petkov. . Move the UI files from tools/perf/util/ui/ to tools/perf/ui/. Also move the GTK+ browser to tools/perf/ui/gtk/, from Namhyung Kim. . Only fallback to sw cycles counter on ENOENT for the hw cycles, from Robert Richter . Trivial fixes from Robert Richter . Handle the autogenerated bison/flex files better, from Namhyung and Jiri Olsa. . Navigate jump instructions in the annotate browser, just press enter or ->, still needs support for a jump navigation history, i.e. to go back. . Search string in the annotate browser: same keys as vim: / forward n next backward/forward ? backward . Clarify number of events/samples in the report header, from Ashay Rane Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com> Signed-off-by: Ingo Molnar <mingo@kernel.org>
Diffstat (limited to 'Documentation/dynamic-debug-howto.txt')
-rw-r--r--Documentation/dynamic-debug-howto.txt30
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