dynamic_debug: add trim_prefix() to provide source-root relative paths

trim_prefix(path) skips past the absolute source path root, and
returns the pointer to the relative path from there.  It is used to
shorten the displayed path in $DBGMT/dynamic_debug/control via
ddebug_proc_show(), and in ddebug_change() to allow relative filenames
to be used in applied queries.  For example:

  ~# echo file kernel/freezer.c +p > $DBGMT/dynamic_debug/control

  kernel/freezer.c:128 [freezer]cancel_freezing p "  clean up: %s\012"

trim_prefix(path) insures common prefix before trimming it, so
out-of-tree module paths are shown as full absolute paths.

Signed-off-by: Jim Cromie <jim.cromie@gmail.com>
Signed-off-by: Jason Baron <jbaron@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
This commit is contained in:
Jim Cromie 2011-12-19 17:13:12 -05:00 committed by Greg Kroah-Hartman
parent 7281491c59
commit 2b6783191d
2 changed files with 19 additions and 6 deletions

View File

@ -144,11 +144,12 @@ 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

View File

@ -69,6 +69,17 @@ static inline const char *basename(const char *path)
return tail ? tail+1 : path;
}
/* Return the path relative to source root */
static inline const char *trim_prefix(const char *path)
{
int skip = strlen(__FILE__) - strlen("lib/dynamic_debug.c");
if (strncmp(path, __FILE__, skip))
skip = 0; /* prefix mismatch, don't skip */
return path + skip;
}
static struct { unsigned flag:8; char opt_char; } opt_array[] = {
{ _DPRINTK_FLAGS_PRINT, 'p' },
{ _DPRINTK_FLAGS_INCL_MODNAME, 'm' },
@ -125,7 +136,8 @@ static void ddebug_change(const struct ddebug_query *query,
/* match against the source filename */
if (query->filename &&
strcmp(query->filename, dp->filename) &&
strcmp(query->filename, basename(dp->filename)))
strcmp(query->filename, basename(dp->filename)) &&
strcmp(query->filename, trim_prefix(dp->filename)))
continue;
/* match against the function */
@ -154,7 +166,7 @@ static void ddebug_change(const struct ddebug_query *query,
dp->flags = newflags;
if (verbose)
pr_info("changed %s:%d [%s]%s =%s\n",
dp->filename, dp->lineno,
trim_prefix(dp->filename), dp->lineno,
dt->mod_name, dp->function,
ddebug_describe_flags(dp, flagbuf,
sizeof(flagbuf)));
@ -714,7 +726,7 @@ static int ddebug_proc_show(struct seq_file *m, void *p)
}
seq_printf(m, "%s:%u [%s]%s =%s \"",
dp->filename, dp->lineno,
trim_prefix(dp->filename), dp->lineno,
iter->table->mod_name, dp->function,
ddebug_describe_flags(dp, flagsbuf, sizeof(flagsbuf)));
seq_escape(m, dp->format, "\t\r\n\"");