From caa20d974c86af496b419eef70010e63b7fab7ac Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Mon, 17 May 2010 16:24:16 -0700 Subject: async_tx: trim dma_async_tx_descriptor in 'no channel switch' case Saves 24 bytes per descriptor (64-bit) when the channel-switching capabilities of async_tx are not required. Signed-off-by: Dan Williams --- include/linux/dmaengine.h | 60 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 60 insertions(+) (limited to 'include/linux/dmaengine.h') diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h index 20ea12c86fd0..cb234979fc6b 100644 --- a/include/linux/dmaengine.h +++ b/include/linux/dmaengine.h @@ -230,11 +230,71 @@ struct dma_async_tx_descriptor { dma_cookie_t (*tx_submit)(struct dma_async_tx_descriptor *tx); dma_async_tx_callback callback; void *callback_param; +#ifndef CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH struct dma_async_tx_descriptor *next; struct dma_async_tx_descriptor *parent; spinlock_t lock; +#endif }; +#ifdef CONFIG_ASYNC_TX_DISABLE_CHANNEL_SWITCH +static inline void txd_lock(struct dma_async_tx_descriptor *txd) +{ +} +static inline void txd_unlock(struct dma_async_tx_descriptor *txd) +{ +} +static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next) +{ + BUG(); +} +static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd) +{ +} +static inline void txd_clear_next(struct dma_async_tx_descriptor *txd) +{ +} +static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd) +{ + return NULL; +} +static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd) +{ + return NULL; +} + +#else +static inline void txd_lock(struct dma_async_tx_descriptor *txd) +{ + spin_lock_bh(&txd->lock); +} +static inline void txd_unlock(struct dma_async_tx_descriptor *txd) +{ + spin_unlock_bh(&txd->lock); +} +static inline void txd_chain(struct dma_async_tx_descriptor *txd, struct dma_async_tx_descriptor *next) +{ + txd->next = next; + next->parent = txd; +} +static inline void txd_clear_parent(struct dma_async_tx_descriptor *txd) +{ + txd->parent = NULL; +} +static inline void txd_clear_next(struct dma_async_tx_descriptor *txd) +{ + txd->next = NULL; +} +static inline struct dma_async_tx_descriptor *txd_parent(struct dma_async_tx_descriptor *txd) +{ + return txd->parent; +} +static inline struct dma_async_tx_descriptor *txd_next(struct dma_async_tx_descriptor *txd) +{ + return txd->next; +} +#endif + /** * struct dma_device - info on the entity supplying DMA services * @chancnt: how many DMA channels are supported -- cgit v1.2.2