From 0579f91dd74a0902e52d1e6e839cc31b99f12cfc Mon Sep 17 00:00:00 2001 From: Thomas Rast Date: Mon, 12 Dec 2011 22:16:07 +0100 Subject: grep: enable threading with -p and -W using lazy attribute lookup Lazily load the userdiff attributes in match_funcname(). Use a separate mutex around this loading to protect the (not thread-safe) attributes machinery. This lets us re-enable threading with -p and -W while reducing the overhead caused by looking up attributes. Signed-off-by: Thomas Rast Signed-off-by: Junio C Hamano --- grep.c | 73 ++++++++++++++++++++++++++++++++++++++++-------------------------- 1 file changed, 44 insertions(+), 29 deletions(-) (limited to 'grep.c') diff --git a/grep.c b/grep.c index 7a070e97c4..486230b511 100644 --- a/grep.c +++ b/grep.c @@ -806,10 +806,46 @@ static void show_line(struct grep_opt *opt, char *bol, char *eol, opt->output(opt, "\n", 1); } -static int match_funcname(struct grep_opt *opt, char *bol, char *eol) +#ifndef NO_PTHREADS +/* + * This lock protects access to the gitattributes machinery, which is + * not thread-safe. + */ +pthread_mutex_t grep_attr_mutex; + +static inline void grep_attr_lock(struct grep_opt *opt) +{ + if (opt->use_threads) + pthread_mutex_lock(&grep_attr_mutex); +} + +static inline void grep_attr_unlock(struct grep_opt *opt) +{ + if (opt->use_threads) + pthread_mutex_unlock(&grep_attr_mutex); +} +#else +#define grep_attr_lock(opt) +#define grep_attr_unlock(opt) +#endif + +static int match_funcname(struct grep_opt *opt, const char *name, char *bol, char *eol) { xdemitconf_t *xecfg = opt->priv; - if (xecfg && xecfg->find_func) { + if (xecfg && !xecfg->find_func) { + struct userdiff_driver *drv; + grep_attr_lock(opt); + drv = userdiff_find_by_path(name); + grep_attr_unlock(opt); + if (drv && drv->funcname.pattern) { + const struct userdiff_funcname *pe = &drv->funcname; + xdiff_set_find_func(xecfg, pe->pattern, pe->cflags); + } else { + xecfg = opt->priv = NULL; + } + } + + if (xecfg) { char buf[1]; return xecfg->find_func(bol, eol - bol, buf, 1, xecfg->find_func_priv) >= 0; @@ -835,7 +871,7 @@ static void show_funcname_line(struct grep_opt *opt, const char *name, if (lno <= opt->last_shown) break; - if (match_funcname(opt, bol, eol)) { + if (match_funcname(opt, name, bol, eol)) { show_line(opt, bol, eol, name, lno, '='); break; } @@ -848,7 +884,7 @@ static void show_pre_context(struct grep_opt *opt, const char *name, char *buf, unsigned cur = lno, from = 1, funcname_lno = 0; int funcname_needed = !!opt->funcname; - if (opt->funcbody && !match_funcname(opt, bol, end)) + if (opt->funcbody && !match_funcname(opt, name, bol, end)) funcname_needed = 2; if (opt->pre_context < lno) @@ -864,7 +900,7 @@ static void show_pre_context(struct grep_opt *opt, const char *name, char *buf, while (bol > buf && bol[-1] != '\n') bol--; cur--; - if (funcname_needed && match_funcname(opt, bol, eol)) { + if (funcname_needed && match_funcname(opt, name, bol, eol)) { funcname_lno = cur; funcname_needed = 0; } @@ -942,19 +978,6 @@ static int look_ahead(struct grep_opt *opt, return 0; } -int grep_threads_ok(const struct grep_opt *opt) -{ - /* If this condition is true, then we may use the attribute - * machinery in grep_buffer_1. The attribute code is not - * thread safe, so we disable the use of threads. - */ - if ((opt->funcname || opt->funcbody) - && !opt->unmatch_name_only && !opt->status_only && !opt->name_only) - return 0; - - return 1; -} - static void std_output(struct grep_opt *opt, const void *buf, size_t size) { fwrite(buf, size, 1, stdout); @@ -1008,16 +1031,8 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name, } memset(&xecfg, 0, sizeof(xecfg)); - if ((opt->funcname || opt->funcbody) - && !opt->unmatch_name_only && !opt->status_only && - !opt->name_only && !binary_match_only && !collect_hits) { - struct userdiff_driver *drv = userdiff_find_by_path(name); - if (drv && drv->funcname.pattern) { - const struct userdiff_funcname *pe = &drv->funcname; - xdiff_set_find_func(&xecfg, pe->pattern, pe->cflags); - opt->priv = &xecfg; - } - } + opt->priv = &xecfg; + try_lookahead = should_lookahead(opt); while (left) { @@ -1093,7 +1108,7 @@ static int grep_buffer_1(struct grep_opt *opt, const char *name, show_function = 1; goto next_line; } - if (show_function && match_funcname(opt, bol, eol)) + if (show_function && match_funcname(opt, name, bol, eol)) show_function = 0; if (show_function || (last_hit && lno <= last_hit + opt->post_context)) { -- cgit v1.2.1