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modutils: merge module_entry and module_info to common

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This merges the in-memory module info structures of modprobe
and depmod. This allows sharing hashing by modulename code
improving depmod runtime with almost factor of 2x.

function                                             old     new   delta
get_or_add_modentry                                    -      17     +17
do_modprobe                                          590     601     +11
moddb_get_or_create                                    -      10     +10
load_modules_dep                                     195     205     +10
moddb_get                                              -       7      +7
add_probe                                             81      78      -3
modprobe_main                                        721     714      -7
depmod_main                                          553     543     -10
config_file_action                                   434     421     -13
helper_get_module                                    160     144     -16
parse_module                                         343     320     -23
order_dep_list                                       105      82     -23
------------------------------------------------------------------------------
(add/remove: 3/0 grow/shrink: 2/7 up/down: 55/-95)            Total: -40 bytes

Signed-off-by: Timo Teräs <timo.teras@iki.fi>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Timo Teräs
2015-11-05 18:54:55 +01:00
committed by Denys Vlasenko
parent 34adecc2b0
commit 48dc80bbba
4 changed files with 113 additions and 120 deletions
Download Patch File Download Diff File Expand all files Collapse all files

66
modutils/modprobe.c
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@ -150,19 +150,6 @@ static const char modprobe_longopts[] ALIGN1 =
#define MODULE_FLAG_FOUND_IN_MODDEP 0x0004
#define MODULE_FLAG_BLACKLISTED 0x0008
struct module_entry { /* I'll call it ME. */
unsigned flags;
char *modname; /* stripped of /path/, .ext and s/-/_/g */
const char *probed_name; /* verbatim as seen on cmdline */
char *options; /* options from config files */
llist_t *realnames; /* strings. if this module is an alias, */
/* real module name is one of these. */
//Can there really be more than one? Example from real kernel?
llist_t *deps; /* strings. modules we depend on */
};
#define DB_HASH_SIZE 256
struct globals {
llist_t *probes; /* MEs of module(s) requested on cmdline */
char *cmdline_mopts; /* module options from cmdline */
@ -170,7 +157,7 @@ struct globals {
/* 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) */
module_db db;
} FIX_ALIASING;
#define G (*ptr_to_globals)
#define INIT_G() do { \
@ -195,51 +182,9 @@ 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)
static struct module_entry *get_or_add_modentry(const char *module)
{
char modname[MODULE_NAME_LEN];
struct module_entry *e;
llist_t *l;
unsigned i;
unsigned hash;
filename2modname(module, modname);
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;
}
if (!create)
return NULL;
e = xzalloc(sizeof(*e));
e->modname = xstrdup(modname);
llist_add_to(&G.db[hash], e);
return e;
}
static ALWAYS_INLINE struct module_entry *get_or_add_modentry(const char *module)
{
return helper_get_module(module, 1);
}
/* So far this function always gets a module pathname, never an alias name.
* The crucial difference is that pathname needs dirname stripping,
* while alias name must NOT do it!
* Testcase where dirname stripping is likely to go wrong: "modprobe devname:snd/timer"
*/
static ALWAYS_INLINE struct module_entry *get_modentry(const char *pathname)
{
return helper_get_module(bb_get_last_path_component_nostrip(pathname), 0);
return moddb_get_or_create(&G.db, module);
}
static void add_probe(const char *name)
@ -536,7 +481,7 @@ static void load_modules_dep(void)
continue;
*colon = '\0';
m = get_modentry(tokens[0]);
m = moddb_get(&G.db, bb_get_last_path_component_nostrip(tokens[0]));
if (m == NULL)
continue;
@ -697,5 +642,8 @@ int modprobe_main(int argc UNUSED_PARAM, char **argv)
} while (me->realnames != NULL);
}
if (ENABLE_FEATURE_CLEAN_UP)
moddb_free(&G.db);
return (rc != 0);
}