From 7e146b55866d1176f80439fdc2be2915147468b3 Mon Sep 17 00:00:00 2001 From: Dimitris Papastamos Date: Thu, 19 May 2011 13:45:30 +0100 Subject: 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 Acked-by: Liam Girdwood Signed-off-by: Mark Brown --- sound/soc/soc-cache.c | 37 +++++++++++++++++++++++++++++++++++++ 1 file changed, 37 insertions(+) (limited to 'sound/soc/soc-cache.c') 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; -- cgit