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e12e0acb9

Timo Teras

2011-06-20

FAILED Duration: 302s

Subject

modprobe: use hash table. speeds up significantly if modprobe.dep is large

Binary

No binary (build failed)

Architecture & Compiler Flags

Architecture: x86_64-linux-gnu Compiler: gcc (Ubuntu 11.4.0-1ubuntu1~22.04.3) 11.4.0

—

Build Log

(log yok)

Commit Diff GitHub →

modutils/modprobe.c +29 -14

modutils/modprobe.c+29 -14

@@ -157,20 +157,21 @@ struct module_entry { /* I'll call it ME. */
	llist_t deps; / strings. modules we depend on */
	};

+	#define DB_HASH_SIZE 256
+
	struct globals {
-	llist_t db; / MEs of all modules ever seen (caching for speed) */
	llist_t probes; / MEs of module(s) requested on cmdline */
	char cmdline_mopts; / module options from cmdline */
	int num_unresolved_deps;
	/* bool. "Did we have 'symbol:FOO' requested on cmdline?" */
	smallint need_symbols;
	struct utsname uts;
+	llist_t db[DB_HASH_SIZE]; / MEs of all modules ever seen (caching for speed) */
	} FIX_ALIASING;
-	#define G ((struct globals)&bb_common_bufsiz1)
-	#define INIT_G() do { } while (0)
-	struct BUG_G_too_big {
-	char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1];
-	};
+	#define G (*ptr_to_globals)
+	#define INIT_G() do { \
+	SET_PTR_TO_GLOBALS(xzalloc(sizeof(G))); \
+	} while (0)


	static int read_config(const char *path);
@@ -190,14 +191,26 @@ static char gather_options_str(char opts, const char *append)
	return opts;
	}

+	/* These three functions called many times, optimizing for speed.
+	* Users reported minute-long delays when they runn iptables repeatedly
+	* (iptables use modprobe to install needed kernel modules).
+	*/
	static struct module_entry helper_get_module(const char module, int create)
	{
	char modname[MODULE_NAME_LEN];
	struct module_entry *e;
	llist_t *l;
+	unsigned i;
+	unsigned hash;

	filename2modname(module, modname);
-	for (l = G.db; l != NULL; l = l->link) {
+
+	hash = 0;
+	for (i = 0; modname[i]; i++)
+	hash = ((hash << 5) + hash) + modname[i];
+	hash %= DB_HASH_SIZE;
+
+	for (l = G.db[hash]; l; l = l->link) {
	e = (struct module_entry *) l->data;
	if (strcmp(e->modname, modname) == 0)
	return e;
@@ -207,15 +220,15 @@ static struct module_entry helper_get_module(const char module, int create)

	e = xzalloc(sizeof(*e));
	e->modname = xstrdup(modname);
-	llist_add_to(&G.db, e);
+	llist_add_to(&G.db[hash], e);

	return e;
	}
-	static struct module_entry get_or_add_modentry(const char module)
+	static ALWAYS_INLINE struct module_entry get_or_add_modentry(const char module)
	{
	return helper_get_module(module, 1);
	}
-	static struct module_entry get_modentry(const char module)
+	static ALWAYS_INLINE struct module_entry get_modentry(const char module)
	{
	return helper_get_module(module, 0);
	}
@@ -275,7 +288,7 @@ static int FAST_FUNC config_file_action(const char *filename,
	continue;
	filename2modname(tokens[1], wildcard);

-	for (l = G.probes; l != NULL; l = l->link) {
+	for (l = G.probes; l; l = l->link) {
	m = (struct module_entry *) l->data;
	if (fnmatch(wildcard, m->modname, 0) != 0)
	continue;
@@ -377,7 +390,6 @@ static char parse_and_add_kcmdline_module_options(char options, const char *mo
	static int do_modprobe(struct module_entry *m)
	{
	int rc, first;
-	llist_t *l;

	if (!(m->flags & MODULE_FLAG_FOUND_IN_MODDEP)) {
	if (!(option_mask32 & INSMOD_OPT_SILENT))
@@ -390,8 +402,11 @@ static int do_modprobe(struct module_entry *m)
	if (!(option_mask32 & OPT_REMOVE))
	m->deps = llist_rev(m->deps);

-	for (l = m->deps; l != NULL; l = l->link)
-	DBG("dep: %s", l->data);
+	if (0) {
+	llist_t *l;
+	for (l = m->deps; l; l = l->link)
+	DBG("dep: %s", l->data);
+	}

	first = 1;
	rc = 0;