Author: ian Date: Mon Mar 4 16:50:01 2013 New Revision: 247803 URL: http://svnweb.freebsd.org/changeset/base/247803
Log: MFC r246134 ... Improve devd startup time, by tweaking some string handling routines that are heavily used when parsing config files. Mostly these changes avoid making temporary copies of the strings, and avoid doing byte at a time append operations, on the most-used code path. On a 1.2 GHz ARM processor this reduces the time to parse the config files from 13 to 6 seconds. Modified: stable/9/sbin/devd/devd.cc stable/9/sbin/devd/devd.hh Directory Properties: stable/9/sbin/devd/ (props changed) Modified: stable/9/sbin/devd/devd.cc ============================================================================== --- stable/9/sbin/devd/devd.cc Mon Mar 4 16:44:19 2013 (r247802) +++ stable/9/sbin/devd/devd.cc Mon Mar 4 16:50:01 2013 (r247803) @@ -137,7 +137,7 @@ config cfg; event_proc::event_proc() : _prio(-1) { - // nothing + _epsvec.reserve(4); } event_proc::~event_proc() @@ -241,25 +241,18 @@ my_system(const char *command) bool action::do_action(config &c) { - string s = c.expand_string(_cmd); + string s = c.expand_string(_cmd.c_str()); if (Dflag) fprintf(stderr, "Executing '%s'\n", s.c_str()); my_system(s.c_str()); return (true); } -match::match(config &c, const char *var, const char *re) - : _var(var), _re("^") +match::match(config &c, const char *var, const char *re) : + _inv(re[0] == '!'), + _var(var), + _re(c.expand_string(_inv ? re + 1 : re, "^", "$")) { - if (!c.expand_string(string(re)).empty() && - c.expand_string(string(re)).at(0) == '!') { - _re.append(c.expand_string(string(re)).substr(1)); - _inv = 1; - } else { - _re.append(c.expand_string(string(re))); - _inv = 0; - } - _re.append("$"); regcomp(&_regex, _re.c_str(), REG_EXTENDED | REG_NOSUB | REG_ICASE); } @@ -625,24 +618,37 @@ config::expand_one(const char *&src, str do { buffer.append(src++, 1); } while (is_id_char(*src)); - buffer.append("", 1); dst.append(get_variable(buffer.c_str())); } const string -config::expand_string(const string &s) +config::expand_string(const char *src, const char *prepend, const char *append) { - const char *src; + const char *var_at; string dst; - src = s.c_str(); - while (*src) { - if (*src == '$') - expand_one(src, dst); - else - dst.append(src++, 1); + /* + * 128 bytes is enough for 2427 of 2438 expansions that happen + * while parsing config files, as tested on 2013-01-30. + */ + dst.reserve(128); + + if (prepend != NULL) + dst = prepend; + + for (;;) { + var_at = strchr(src, '$'); + if (var_at == NULL) { + dst.append(src); + break; + } + dst.append(src, var_at - src); + src = var_at; + expand_one(src, dst); } - dst.append("", 1); + + if (append != NULL) + dst.append(append); return (dst); } Modified: stable/9/sbin/devd/devd.hh ============================================================================== --- stable/9/sbin/devd/devd.hh Mon Mar 4 16:44:19 2013 (r247802) +++ stable/9/sbin/devd/devd.hh Mon Mar 4 16:50:01 2013 (r247803) @@ -90,9 +90,9 @@ public: virtual bool do_match(config &); virtual bool do_action(config &) { return true; } private: + bool _inv; std::string _var; std::string _re; - bool _inv; regex_t _regex; }; @@ -162,7 +162,8 @@ public: void pop_var_table(); void set_variable(const char *var, const char *val); const std::string &get_variable(const std::string &var); - const std::string expand_string(const std::string &var); + const std::string expand_string(const char * var, + const char * prepend = NULL, const char * append = NULL); char *set_vars(char *); void find_and_execute(char); protected: _______________________________________________ svn-src-all@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/svn-src-all To unsubscribe, send any mail to "svn-src-all-unsubscr...@freebsd.org"