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e1000e: Remove unnecessary use of kmap_atomic()

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alloc_rx_buf() allocates ps_page->page and buffer_info->page using either
GFP_ATOMIC or GFP_KERNEL. Memory allocated with GFP_KERNEL/GFP_ATOMIC can't
come from highmem and so there's no need to kmap() them. Just use
page_address().

I don't have access to a 32-bit system so did some limited testing on qemu
(qemu-system-i386 -m 4096 -smp 4 -device e1000e) with a 32-bit Debian 11.04
image.

Cc: Ira Weiny <ira.weiny@intel.com>
Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Cc: Jesse Brandeburg <jesse.brandeburg@intel.com>
Cc: Tony Nguyen <anthony.l.nguyen@intel.com>
Suggested-by: Ira Weiny <ira.weiny@intel.com>
Suggested-by: Fabio M. De Francesco <fmdefrancesco@gmail.com>
Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
Tested-by: Naama Meir <naamax.meir@linux.intel.com>
Signed-off-by: Tony Nguyen <anthony.l.nguyen@intel.com>
This commit is contained in:
Anirudh Venkataramanan
2022-09-30 15:33:24 -07:00
committed by Tony Nguyen
parent 7bab8828e1
commit ab400b0dd4
1 changed files with 5 additions and 15 deletions
Download Patch File Download Diff File Expand all files Collapse all files

20
drivers/net/ethernet/intel/e1000e/netdev.c
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@@ -1391,26 +1391,18 @@ static bool e1000_clean_rx_irq_ps(struct e1000_ring *rx_ring, int *work_done,
/* page alloc/put takes too long and effects small
* packet throughput, so unsplit small packets and
* save the alloc/put only valid in softirq (napi)
* context to call kmap_*
* save the alloc/put
*/
if (l1 && (l1 <= copybreak) &&
((length + l1) <= adapter->rx_ps_bsize0)) {
u8 *vaddr;
ps_page = &buffer_info->ps_pages[0];
/* there is no documentation about how to call
* kmap_atomic, so we can't hold the mapping
* very long
*/
dma_sync_single_for_cpu(&pdev->dev,
ps_page->dma,
PAGE_SIZE,
DMA_FROM_DEVICE);
vaddr = kmap_atomic(ps_page->page);
memcpy(skb_tail_pointer(skb), vaddr, l1);
kunmap_atomic(vaddr);
memcpy(skb_tail_pointer(skb),
page_address(ps_page->page), l1);
dma_sync_single_for_device(&pdev->dev,
ps_page->dma,
PAGE_SIZE,
@@ -1610,11 +1602,9 @@ static bool e1000_clean_jumbo_rx_irq(struct e1000_ring *rx_ring, int *work_done,
*/
if (length <= copybreak &&
skb_tailroom(skb) >= length) {
u8 *vaddr;
vaddr = kmap_atomic(buffer_info->page);
memcpy(skb_tail_pointer(skb), vaddr,
memcpy(skb_tail_pointer(skb),
page_address(buffer_info->page),
length);
kunmap_atomic(vaddr);
/* re-use the page, so don't erase
* buffer_info->page
*/