diff options
| author | Dan Williams <dan.j.williams@intel.com> | 2009-09-08 21:01:38 +0200 |
|---|---|---|
| committer | Dan Williams <dan.j.williams@intel.com> | 2009-09-09 02:30:24 +0200 |
| commit | ad643f54c8514998333bc6c7b201fda2267496be (patch) | |
| tree | c92bbecd74912ada08dfa94662b52e63d4c5df46 /drivers/dma | |
| parent | ioat: ___devinit annotate the initialization paths (diff) | |
| download | linux-ad643f54c8514998333bc6c7b201fda2267496be.tar.xz linux-ad643f54c8514998333bc6c7b201fda2267496be.zip | |
ioat1: trim ioat_dma_desc_sw
Save 4 bytes per software descriptor by transmitting tx_cnt in an unused
portion of the hardware descriptor.
Signed-off-by: Maciej Sosnowski <maciej.sosnowski@intel.com>
Signed-off-by: Dan Williams <dan.j.williams@intel.com>
Diffstat (limited to 'drivers/dma')
| -rw-r--r-- | drivers/dma/ioat/dma.c | 4 | ||||
| -rw-r--r-- | drivers/dma/ioat/dma.h | 2 | ||||
| -rw-r--r-- | drivers/dma/ioat/hw.h | 6 |
3 files changed, 7 insertions, 5 deletions
diff --git a/drivers/dma/ioat/dma.c b/drivers/dma/ioat/dma.c index abc96c4c0796..f59b6f42f866 100644 --- a/drivers/dma/ioat/dma.c +++ b/drivers/dma/ioat/dma.c @@ -396,7 +396,7 @@ static dma_cookie_t ioat1_tx_submit(struct dma_async_tx_descriptor *tx) dump_desc_dbg(ioat, chain_tail); dump_desc_dbg(ioat, first); - ioat->pending += desc->tx_cnt; + ioat->pending += desc->hw->tx_cnt; if (ioat->pending >= ioat_pending_level) __ioat1_dma_memcpy_issue_pending(ioat); spin_unlock_bh(&ioat->desc_lock); @@ -655,11 +655,11 @@ ioat1_dma_prep_memcpy(struct dma_chan *c, dma_addr_t dma_dest, spin_unlock_bh(&ioat->desc_lock); desc->txd.flags = flags; - desc->tx_cnt = tx_cnt; desc->len = total_len; list_splice(&chain, &desc->txd.tx_list); hw->ctl_f.int_en = !!(flags & DMA_PREP_INTERRUPT); hw->ctl_f.compl_write = 1; + hw->tx_cnt = tx_cnt; dump_desc_dbg(ioat, desc); return &desc->txd; diff --git a/drivers/dma/ioat/dma.h b/drivers/dma/ioat/dma.h index e47083b52ee7..ec851cf5345c 100644 --- a/drivers/dma/ioat/dma.h +++ b/drivers/dma/ioat/dma.h @@ -165,14 +165,12 @@ ioat_is_complete(struct dma_chan *c, dma_cookie_t cookie, * @hw: hardware DMA descriptor * @node: this descriptor will either be on the free list, * or attached to a transaction list (async_tx.tx_list) - * @tx_cnt: number of descriptors required to complete the transaction * @txd: the generic software descriptor for all engines * @id: identifier for debug */ struct ioat_desc_sw { struct ioat_dma_descriptor *hw; struct list_head node; - int tx_cnt; size_t len; struct dma_async_tx_descriptor txd; #ifdef DEBUG diff --git a/drivers/dma/ioat/hw.h b/drivers/dma/ioat/hw.h index e13f3ed47763..7481fb13ce00 100644 --- a/drivers/dma/ioat/hw.h +++ b/drivers/dma/ioat/hw.h @@ -63,7 +63,11 @@ struct ioat_dma_descriptor { uint64_t next; uint64_t rsv1; uint64_t rsv2; - uint64_t user1; + /* store some driver data in an unused portion of the descriptor */ + union { + uint64_t user1; + uint64_t tx_cnt; + }; uint64_t user2; }; #endif |