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authorDimitris Papastamos <dp@opensource.wolfsonmicro.com>2011-05-19 16:45:30 +0400
committerMark Brown <broonie@opensource.wolfsonmicro.com>2011-05-20 14:22:06 +0400
commit7e146b55866d1176f80439fdc2be2915147468b3 (patch)
tree78409086ae8f445e6e8ce9e0997df3523a4f647a /sound/soc/soc-cache.c
parent0944cc392e9a41dd36b65b2f8cb31dff437a9fdb (diff)
downloadlinux-7e146b55866d1176f80439fdc2be2915147468b3.tar.xz
ASoC: soc-cache: Cache a pointer to the last accessed rbnode
Whenever we are doing a read or a write through the rbtree code, we'll cache a pointer to the rbnode. To avoid looking up the register everytime we do a read or a write, we first check if it can be found in the cached register block, otherwise we traverse the rbtree and finally cache the rbnode for future use. Signed-off-by: Dimitris Papastamos <dp@opensource.wolfsonmicro.com> Acked-by: Liam Girdwood <lrg@ti.com> Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Diffstat (limited to 'sound/soc/soc-cache.c')
-rw-r--r--sound/soc/soc-cache.c37
1 files changed, 37 insertions, 0 deletions
diff --git a/sound/soc/soc-cache.c b/sound/soc/soc-cache.c
index 78c9869615df..5cd23daff4ad 100644
--- a/sound/soc/soc-cache.c
+++ b/sound/soc/soc-cache.c
@@ -604,6 +604,7 @@ struct snd_soc_rbtree_node {
struct snd_soc_rbtree_ctx {
struct rb_root root;
+ struct snd_soc_rbtree_node *cached_rbnode;
};
static inline void snd_soc_rbtree_get_base_top_reg(
@@ -780,11 +781,28 @@ static int snd_soc_rbtree_cache_write(struct snd_soc_codec *codec,
struct rb_node *node;
unsigned int val;
unsigned int reg_tmp;
+ unsigned int base_reg, top_reg;
unsigned int pos;
int i;
int ret;
rbtree_ctx = codec->reg_cache;
+ /* look up the required register in the cached rbnode */
+ rbnode = rbtree_ctx->cached_rbnode;
+ if (rbnode) {
+ snd_soc_rbtree_get_base_top_reg(rbnode, &base_reg, &top_reg);
+ if (reg >= base_reg && reg <= top_reg) {
+ reg_tmp = reg - base_reg;
+ val = snd_soc_rbtree_get_register(rbnode, reg_tmp);
+ if (val == value)
+ return 0;
+ snd_soc_rbtree_set_register(rbnode, reg_tmp, value);
+ return 0;
+ }
+ }
+ /* if we can't locate it in the cached rbnode we'll have
+ * to traverse the rbtree looking for it.
+ */
rbnode = snd_soc_rbtree_lookup(&rbtree_ctx->root, reg);
if (rbnode) {
reg_tmp = reg - rbnode->base_reg;
@@ -792,6 +810,7 @@ static int snd_soc_rbtree_cache_write(struct snd_soc_codec *codec,
if (val == value)
return 0;
snd_soc_rbtree_set_register(rbnode, reg_tmp, value);
+ rbtree_ctx->cached_rbnode = rbnode;
} else {
/* bail out early, no need to create the rbnode yet */
if (!value)
@@ -813,6 +832,7 @@ static int snd_soc_rbtree_cache_write(struct snd_soc_codec *codec,
reg, value);
if (ret)
return ret;
+ rbtree_ctx->cached_rbnode = rbnode_tmp;
return 0;
}
}
@@ -835,6 +855,7 @@ static int snd_soc_rbtree_cache_write(struct snd_soc_codec *codec,
}
snd_soc_rbtree_set_register(rbnode, 0, value);
snd_soc_rbtree_insert(&rbtree_ctx->root, rbnode);
+ rbtree_ctx->cached_rbnode = rbnode;
}
return 0;
@@ -845,13 +866,28 @@ static int snd_soc_rbtree_cache_read(struct snd_soc_codec *codec,
{
struct snd_soc_rbtree_ctx *rbtree_ctx;
struct snd_soc_rbtree_node *rbnode;
+ unsigned int base_reg, top_reg;
unsigned int reg_tmp;
rbtree_ctx = codec->reg_cache;
+ /* look up the required register in the cached rbnode */
+ rbnode = rbtree_ctx->cached_rbnode;
+ if (rbnode) {
+ snd_soc_rbtree_get_base_top_reg(rbnode, &base_reg, &top_reg);
+ if (reg >= base_reg && reg <= top_reg) {
+ reg_tmp = reg - base_reg;
+ *value = snd_soc_rbtree_get_register(rbnode, reg_tmp);
+ return 0;
+ }
+ }
+ /* if we can't locate it in the cached rbnode we'll have
+ * to traverse the rbtree looking for it.
+ */
rbnode = snd_soc_rbtree_lookup(&rbtree_ctx->root, reg);
if (rbnode) {
reg_tmp = reg - rbnode->base_reg;
*value = snd_soc_rbtree_get_register(rbnode, reg_tmp);
+ rbtree_ctx->cached_rbnode = rbnode;
} else {
/* uninitialized registers default to 0 */
*value = 0;
@@ -902,6 +938,7 @@ static int snd_soc_rbtree_cache_init(struct snd_soc_codec *codec)
rbtree_ctx = codec->reg_cache;
rbtree_ctx->root = RB_ROOT;
+ rbtree_ctx->cached_rbnode = NULL;
if (!codec->reg_def_copy)
return 0;