[RFC 33/34] dmaengine: PL08x: get rid of write only pool_ctr and free_txd locking
Russell King
rmk+kernel at arm.linux.org.uk
Tue May 29 05:46:21 EDT 2012
The free function says the pl08x lock should be taken before calling
it. However, the DMA pool allocation/freeing is already properly
locked. The only thing that would need this is pool_ctr, which
happens to be a write-only variable.
Let's get rid of this, and eliminate any need for additional locking
here.
Signed-off-by: Russell King <rmk+kernel at arm.linux.org.uk>
---
drivers/dma/amba-pl08x.c | 12 ------------
1 files changed, 0 insertions(+), 12 deletions(-)
diff --git a/drivers/dma/amba-pl08x.c b/drivers/dma/amba-pl08x.c
index 9132993..f2a29bf 100644
--- a/drivers/dma/amba-pl08x.c
+++ b/drivers/dma/amba-pl08x.c
@@ -240,7 +240,6 @@ struct pl08x_dma_chan {
* @pd: platform data passed in from the platform/machine
* @phy_chans: array of data for the physical channels
* @pool: a pool for the LLI descriptors
- * @pool_ctr: counter of LLIs in the pool
* @lli_buses: bitmask to or in to LLI pointer selecting AHB port for LLI
* fetches
* @mem_buses: set to indicate memory transfers on AHB2.
@@ -255,7 +254,6 @@ struct pl08x_driver_data {
struct pl08x_platform_data *pd;
struct pl08x_phy_chan *phy_chans;
struct dma_pool *pool;
- int pool_ctr;
u8 lli_buses;
u8 mem_buses;
};
@@ -814,8 +812,6 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
return 0;
}
- pl08x->pool_ctr++;
-
bd.txd = txd;
bd.lli_bus = (pl08x->lli_buses & PL08X_AHB2) ? PL080_LLI_LM_AHB2 : 0;
cctl = txd->cctl;
@@ -1031,18 +1027,14 @@ static int pl08x_fill_llis_for_desc(struct pl08x_driver_data *pl08x,
return num_llis;
}
-/* You should call this with the struct pl08x lock held */
static void pl08x_free_txd(struct pl08x_driver_data *pl08x,
struct pl08x_txd *txd)
{
struct pl08x_sg *dsg, *_dsg;
- /* Free the LLI */
if (txd->llis_va)
dma_pool_free(pl08x->pool, txd->llis_va, txd->llis_bus);
- pl08x->pool_ctr--;
-
list_for_each_entry_safe(dsg, _dsg, &txd->dsg_list, node) {
list_del(&dsg->node);
kfree(dsg);
@@ -1083,8 +1075,6 @@ static void pl08x_desc_free(struct virt_dma_desc *vd)
{
struct pl08x_txd *txd = to_pl08x_txd(&vd->tx);
struct pl08x_dma_chan *plchan = to_pl08x_chan(vd->tx.chan);
- struct pl08x_driver_data *pl08x = plchan->host;
- unsigned long flags;
if (!plchan->slave)
pl08x_unmap_buffers(txd);
@@ -1092,9 +1082,7 @@ static void pl08x_desc_free(struct virt_dma_desc *vd)
if (!txd->done)
pl08x_release_mux(plchan);
- spin_lock_irqsave(&pl08x->lock, flags);
pl08x_free_txd(plchan->host, txd);
- spin_unlock_irqrestore(&pl08x->lock, flags);
}
static void pl08x_free_txd_list(struct pl08x_driver_data *pl08x,
--
1.7.4.4
More information about the linux-arm-kernel
mailing list