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-rw-r--r--Documentation/dynamic-debug-howto.txt23
-rw-r--r--lib/dynamic_debug.c73
2 files changed, 66 insertions, 30 deletions
diff --git a/Documentation/dynamic-debug-howto.txt b/Documentation/dynamic-debug-howto.txt
index 378b5d1bf436..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.
diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index 93fc5d500cd5..310c753cf83e 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -124,13 +124,13 @@ do { \
} while (0)
/*
- * Search the tables for _ddebug's which match the given
- * `query' and apply the `flags' and `mask' to them. Tells
- * the user which ddebug's were changed, or whether none
- * were matched.
+ * Search the tables for _ddebug's which match the given `query' and
+ * apply the `flags' and `mask' to them. Returns number of matching
+ * callsites, normally the same as number of changes. If verbose,
+ * logs the changes. Takes ddebug_lock.
*/
-static void ddebug_change(const struct ddebug_query *query,
- unsigned int flags, unsigned int mask)
+static int ddebug_change(const struct ddebug_query *query,
+ unsigned int flags, unsigned int mask)
{
int i;
struct ddebug_table *dt;
@@ -192,6 +192,8 @@ static void ddebug_change(const struct ddebug_query *query,
if (!nfound && verbose)
pr_info("no matches for query\n");
+
+ return nfound;
}
/*
@@ -449,7 +451,7 @@ static int ddebug_exec_query(char *query_string)
unsigned int flags = 0, mask = 0;
struct ddebug_query query;
#define MAXWORDS 9
- int nwords;
+ int nwords, nfound;
char *words[MAXWORDS];
nwords = ddebug_tokenize(query_string, words, MAXWORDS);
@@ -461,8 +463,47 @@ static int ddebug_exec_query(char *query_string)
return -EINVAL;
/* actually go and implement the change */
- ddebug_change(&query, flags, mask);
- return 0;
+ nfound = ddebug_change(&query, flags, mask);
+ vpr_info_dq((&query), (nfound) ? "applied" : "no-match");
+
+ return nfound;
+}
+
+/* handle multiple queries in query string, continue on error, return
+ last error or number of matching callsites. Module name is either
+ in param (for boot arg) or perhaps in query string.
+*/
+static int ddebug_exec_queries(char *query)
+{
+ char *split;
+ int i, errs = 0, exitcode = 0, rc, nfound = 0;
+
+ for (i = 0; query; query = split) {
+ split = strpbrk(query, ";\n");
+ if (split)
+ *split++ = '\0';
+
+ query = skip_spaces(query);
+ if (!query || !*query || *query == '#')
+ continue;
+
+ if (verbose)
+ pr_info("query %d: \"%s\"\n", i, query);
+
+ rc = ddebug_exec_query(query);
+ if (rc < 0) {
+ errs++;
+ exitcode = rc;
+ } else
+ nfound += rc;
+ i++;
+ }
+ pr_info("processed %d queries, with %d matches, %d errs\n",
+ i, nfound, errs);
+
+ if (exitcode)
+ return exitcode;
+ return nfound;
}
#define PREFIX_SIZE 64
@@ -615,9 +656,9 @@ static ssize_t ddebug_proc_write(struct file *file, const char __user *ubuf,
if (verbose)
pr_info("read %d bytes from userspace\n", (int)len);
- ret = ddebug_exec_query(tmpbuf);
+ ret = ddebug_exec_queries(tmpbuf);
kfree(tmpbuf);
- if (ret)
+ if (ret < 0)
return ret;
*offp += len;
@@ -927,13 +968,15 @@ static int __init dynamic_debug_init(void)
/* ddebug_query boot param got passed -> set it up */
if (ddebug_setup_string[0] != '\0') {
- ret = ddebug_exec_query(ddebug_setup_string);
- if (ret)
+ ret = ddebug_exec_queries(ddebug_setup_string);
+ if (ret < 0)
pr_warn("Invalid ddebug boot param %s",
ddebug_setup_string);
else
- pr_info("ddebug initialized with string %s",
- ddebug_setup_string);
+ pr_info("%d changes by ddebug_query\n", ret);
+
+ /* keep tables even on ddebug_query parse error */
+ ret = 0;
}
out_free: