diff options
| author | Dimitris Papastamos <dp@opensource.wolfsonmicro.com> | 2011-10-03 10:50:14 +0100 |
|---|---|---|
| committer | Mark Brown <broonie@opensource.wolfsonmicro.com> | 2011-10-03 11:50:53 +0100 |
| commit | c08604b8ae72b4fa1843a76fc7b403ddec49f8f4 (patch) | |
| tree | 64de79de1019dbc3fd7862693a245bb29bf25e4b | |
| parent | ac77a765cb6e3b5aa41c186ad9f37db7fdad7dbe (diff) | |
| download | linux-c08604b8ae72b4fa1843a76fc7b403ddec49f8f4.tar.bz2 | |
regmap: Optimize the lookup path to use binary search
Since there are more lookups than insertions in a typical
scenario, optimize the linear search into a binary search. For
this to work, we need to keep reg_defaults sorted upon
insertions, for now be lazy and use sort().
Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
| -rw-r--r-- | drivers/base/regmap/regcache.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/drivers/base/regmap/regcache.c b/drivers/base/regmap/regcache.c index 2d55b261f1c5..e1846eb2f171 100644 --- a/drivers/base/regmap/regcache.c +++ b/drivers/base/regmap/regcache.c @@ -12,6 +12,7 @@ #include <linux/slab.h> #include <trace/events/regmap.h> +#include <linux/sort.h> #include "internal.h" @@ -356,14 +357,30 @@ unsigned int regcache_get_val(const void *base, unsigned int idx, int regcache_lookup_reg(struct regmap *map, unsigned int reg) { - unsigned int i; - - for (i = 0; i < map->num_reg_defaults; i++) - if (map->reg_defaults[i].reg == reg) - return i; + unsigned int min, max, index; + + min = 0; + max = map->num_reg_defaults - 1; + do { + index = (min + max) / 2; + if (map->reg_defaults[index].reg == reg) + return index; + if (map->reg_defaults[index].reg < reg) + min = index + 1; + else + max = index; + } while (min <= max); return -1; } +static int regcache_insert_cmp(const void *a, const void *b) +{ + const struct reg_default *_a = a; + const struct reg_default *_b = b; + + return _a->reg - _b->reg; +} + int regcache_insert_reg(struct regmap *map, unsigned int reg, unsigned int val) { @@ -378,5 +395,7 @@ int regcache_insert_reg(struct regmap *map, unsigned int reg, map->num_reg_defaults++; map->reg_defaults[map->num_reg_defaults - 1].reg = reg; map->reg_defaults[map->num_reg_defaults - 1].def = val; + sort(map->reg_defaults, map->num_reg_defaults, + sizeof(struct reg_default), regcache_insert_cmp, NULL); return 0; } |