On Sat, Oct 25, 2008 at 16:51, Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx> wrote: > C initializers include an implicit "others => 0" (Ada syntax). > Initializing a char array to "" is equivalent to a memset() > call - which is exactly what it gets compiled to. > > Fixing this one callsite reduced memset() _user_ cpu cycles > from 2-4% to 0.05% on the EeePC. > > There are other occurences, but the fix isn't that pretty > so I left them alone. > > Signed-off-by: Alan Jenkins <alan-jenkins@xxxxxxxxxxxxxx> > > diff --git a/udev/udev-rules.c b/udev/udev-rules.c > index 45806c3..ad2b00f 100644 > --- a/udev/udev-rules.c > +++ b/udev/udev-rules.c > @@ -1559,10 +1559,11 @@ static int match_attr(struct udev_rules *rules, struct udev_device *dev, struct > char attr[UTIL_PATH_SIZE]; > const char *key_name = &rules->buf[cur->key.attr_off]; > const char *key_value = &rules->buf[cur->key.value_off]; > - char value[UTIL_NAME_SIZE] = ""; > + char value[UTIL_NAME_SIZE]; > size_t len; > > util_strlcpy(attr, key_name, sizeof(attr)); > + util_strlcpy(value, "", sizeof(value)); Wouldn't value[0] = '\0' be even faster? :) Kay -- To unsubscribe from this list: send the line "unsubscribe linux-hotplug" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
