[PATCH 3/3] dynamic_debug: add pr_errs before -EINVALs

From: Jason Baron
Date: Wed Dec 05 2012 - 16:48:35 EST


From: Jim Cromie <jim.cromie@xxxxxxxxx>

Ma noted that dynamic-debug is silent about many query errors, so add
pr_err()s to explain those errors, and tweak a few others. Also parse
flags 1st, so that match-spec errs are slightly clearer.

CC: Jianpeng Ma <majianpeng@xxxxxxxxx>
CC: Joe Perches <joe@xxxxxxxxxxx>
CC: Greg KH <gregkh@xxxxxxxxxxxxxxxxxxx>
Signed-off-by: Jim Cromie <jim.cromie@xxxxxxxxx>
Signed-off-by: Jason Baron <jbaron@xxxxxxxxxx>
---
lib/dynamic_debug.c | 47 +++++++++++++++++++++++++++++++++++------------
1 files changed, 35 insertions(+), 12 deletions(-)

diff --git a/lib/dynamic_debug.c b/lib/dynamic_debug.c
index c0869f1..da820f2 100644
--- a/lib/dynamic_debug.c
+++ b/lib/dynamic_debug.c
@@ -230,8 +230,10 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
int quote = *buf++;
for (end = buf; *end && *end != quote; end++)
;
- if (!*end)
+ if (!*end) {
+ pr_err("unclosed quote: %s\n", buf);
return -EINVAL; /* unclosed quote */
+ }
} else {
for (end = buf; *end && !isspace(*end); end++)
;
@@ -239,8 +241,10 @@ static int ddebug_tokenize(char *buf, char *words[], int maxwords)
}

/* `buf' is start of word, `end' is one past its end */
- if (nwords == maxwords)
+ if (nwords == maxwords) {
+ pr_err("too many words, legal max <=%d\n", maxwords);
return -EINVAL; /* ran out of words[] before bytes */
+ }
if (*end)
*end++ = '\0'; /* terminate the word */
words[nwords++] = buf;
@@ -272,7 +276,11 @@ static inline int parse_lineno(const char *str, unsigned int *val)
return 0;
}
*val = simple_strtoul(str, &end, 10);
- return end == NULL || end == str || *end != '\0' ? -EINVAL : 0;
+ if (end == NULL || end == str || *end != '\0') {
+ pr_err("bad line-number: %s\n", str);
+ return -EINVAL;
+ }
+ return 0;
}

/*
@@ -352,8 +360,10 @@ static int ddebug_parse_query(char *words[], int nwords,
int rc;

/* check we have an even number of words */
- if (nwords % 2 != 0)
+ if (nwords % 2 != 0) {
+ pr_err("expecting pairs of match-spec <value>\n");
return -EINVAL;
+ }
memset(query, 0, sizeof(*query));

if (modname)
@@ -374,18 +384,22 @@ static int ddebug_parse_query(char *words[], int nwords,
char *first = words[i+1];
char *last = strchr(first, '-');
if (query->first_lineno || query->last_lineno) {
- pr_err("match-spec:line given 2 times\n");
+ pr_err("match-spec: line used 2x\n");
return -EINVAL;
}
if (last)
*last++ = '\0';
- if (parse_lineno(first, &query->first_lineno) < 0)
+ if (parse_lineno(first, &query->first_lineno) < 0) {
+ pr_err("line-number is <0\n");
return -EINVAL;
+ }
if (last) {
/* range <first>-<last> */
if (parse_lineno(last, &query->last_lineno)
< query->first_lineno) {
- pr_err("last-line < 1st-line\n");
+ pr_err("last-line:%d < 1st-line:%d\n",
+ query->last_lineno,
+ query->first_lineno);
return -EINVAL;
}
} else {
@@ -421,6 +435,7 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
op = *str++;
break;
default:
+ pr_err("bad flag-op %c, at start of %s\n", *str, str);
return -EINVAL;
}
vpr_info("op='%c'\n", op);
@@ -432,8 +447,10 @@ static int ddebug_parse_flags(const char *str, unsigned int *flagsp,
break;
}
}
- if (i < 0)
+ if (i < 0) {
+ pr_err("unknown flag '%c' in \"%s\"\n", *str, str);
return -EINVAL;
+ }
}
vpr_info("flags=0x%x\n", flags);

@@ -465,13 +482,19 @@ static int ddebug_exec_query(char *query_string, const char *modname)
char *words[MAXWORDS];

nwords = ddebug_tokenize(query_string, words, MAXWORDS);
- if (nwords <= 0)
+ if (nwords <= 0) {
+ pr_err("tokenize failed\n");
return -EINVAL;
- if (ddebug_parse_query(words, nwords-1, &query, modname))
+ }
+ /* check flags 1st (last arg) so query is pairs of spec,val */
+ if (ddebug_parse_flags(words[nwords-1], &flags, &mask)) {
+ pr_err("flags parse failed\n");
return -EINVAL;
- if (ddebug_parse_flags(words[nwords-1], &flags, &mask))
+ }
+ if (ddebug_parse_query(words, nwords-1, &query, modname)) {
+ pr_err("query parse failed\n");
return -EINVAL;
-
+ }
/* actually go and implement the change */
nfound = ddebug_change(&query, flags, mask);
vpr_info_dq(&query, nfound ? "applied" : "no-match");
--
1.7.1

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