diff options
| author | Steve Hodgson <shodgson@solarflare.com> | 2010-06-01 11:20:53 +0000 |
|---|---|---|
| committer | David S. Miller <davem@davemloft.net> | 2010-06-02 02:21:10 -0700 |
| commit | 62b330baede3849897ce7fc5534eadc34cd03a51 (patch) | |
| tree | 8b1108981cac25a732fed7e488d5a6004e49015e /drivers/net/sfc/net_driver.h | |
| parent | 244558006cf02f0096fb247f3a54dc7e7d81a256 (diff) | |
sfc: Allow shared pages to be recycled
Insert a structure at the start of the shared page that
tracks the dma mapping refcnt. DMA into the next cache
line of the (shared) page (plus EFX_PAGE_IP_ALIGN).
When recycling a page, check the page refcnt. If the
page is otherwise unused, then resurrect the other
receive buffer that previously referenced the page.
Be careful not to overflow the receive ring, since we
can now resurrect n receive buffers in a row.
Signed-off-by: Ben Hutchings <bhutchings@solarflare.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'drivers/net/sfc/net_driver.h')
| -rw-r--r-- | drivers/net/sfc/net_driver.h | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/drivers/net/sfc/net_driver.h b/drivers/net/sfc/net_driver.h index 59c8ecc39ae..40c0d931b18 100644 --- a/drivers/net/sfc/net_driver.h +++ b/drivers/net/sfc/net_driver.h @@ -232,6 +232,24 @@ struct efx_rx_buffer { }; /** + * struct efx_rx_page_state - Page-based rx buffer state + * + * Inserted at the start of every page allocated for receive buffers. + * Used to facilitate sharing dma mappings between recycled rx buffers + * and those passed up to the kernel. + * + * @refcnt: Number of struct efx_rx_buffer's referencing this page. + * When refcnt falls to zero, the page is unmapped for dma + * @dma_addr: The dma address of this page. + */ +struct efx_rx_page_state { + unsigned refcnt; + dma_addr_t dma_addr; + + unsigned int __pad[0] ____cacheline_aligned; +}; + +/** * struct efx_rx_queue - An Efx RX queue * @efx: The associated Efx NIC * @queue: DMA queue number |