Commit 8cf4e6a0 authored by Jean Delvare's avatar Jean Delvare
Browse files

firmware: dmi: Optimize dmi_matches

Function dmi_matches can me made a bit faster:

* The documented purpose of dmi_initialized is to catch too early
  calls to dmi_check_system(). I'm not fully convinced it justifies
  slowing down the initialization of all systems out there, but at
  least the check should not have been moved from dmi_check_system()
  to dmi_matches(). dmi_matches() is being called for every entry of
  the table passed to dmi_check_system(), causing the same redundant
  check to be performed again and again. So move it back to
  dmi_check_system(), reverting this specific portion of commit
  d7b1956f

 ("DMI: Introduce dmi_first_match to make the interface
  more flexible").

* Don't check for the exact_match flag again when we already know its
  value.

Signed-off-by: default avatarJean Delvare <jdelvare@suse.de>
Fixes: d7b1956f ("DMI: Introduce dmi_first_match to make the interface more flexible")
Cc: Jani Nikula <jani.nikula@linux.intel.com>
Cc: Daniel Vetter <daniel.vetter@intel.com>
Cc: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Cc: Jeff Garzik <jgarzik@redhat.com>
parent d8a5b805
......@@ -784,19 +784,20 @@ static bool dmi_matches(const struct dmi_system_id *dmi)
{
int i;
WARN(!dmi_initialized, KERN_ERR "dmi check: not initialized yet.\n");
for (i = 0; i < ARRAY_SIZE(dmi->matches); i++) {
int s = dmi->matches[i].slot;
if (s == DMI_NONE)
break;
if (dmi_ident[s]) {
if (!dmi->matches[i].exact_match &&
strstr(dmi_ident[s], dmi->matches[i].substr))
continue;
else if (dmi->matches[i].exact_match &&
!strcmp(dmi_ident[s], dmi->matches[i].substr))
continue;
if (dmi->matches[i].exact_match) {
if (!strcmp(dmi_ident[s],
dmi->matches[i].substr))
continue;
} else {
if (strstr(dmi_ident[s],
dmi->matches[i].substr))
continue;
}
}
/* No match */
......@@ -832,6 +833,8 @@ int dmi_check_system(const struct dmi_system_id *list)
int count = 0;
const struct dmi_system_id *d;
WARN(!dmi_initialized, KERN_ERR "dmi check: not initialized yet.\n");
for (d = list; !dmi_is_end_of_table(d); d++)
if (dmi_matches(d)) {
count++;
......
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