From: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
To: "Fabio M. De Francesco" <fmdefrancesco@gmail.com>,
<netdev@vger.kernel.org>
Cc: Ira Weiny <ira.weiny@intel.com>
Subject: Re: [PATCH net-next 3/5] cassini: Remove unnecessary use of kmap_atomic()
Date: Fri, 18 Nov 2022 09:55:36 -0800 [thread overview]
Message-ID: <d9a3d57b-e72c-8f8f-b4ae-979836d87d32@intel.com> (raw)
In-Reply-To: <3752791.kQq0lBPeGt@suse>
On 11/18/2022 12:35 AM, Fabio M. De Francesco wrote:
> On giovedì 17 novembre 2022 23:25:55 CET Anirudh Venkataramanan wrote:
>> Pages for Rx buffers are allocated in cas_page_alloc() 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() instead.
>>
>> I don't have hardware, so this change has only been compile tested.
>>
>> Cc: Ira Weiny <ira.weiny@intel.com>
>> Cc: Fabio M. De Francesco <fmdefrancesco@gmail.com>
>> Signed-off-by: Anirudh Venkataramanan <anirudh.venkataramanan@intel.com>
>> ---
>> drivers/net/ethernet/sun/cassini.c | 34 ++++++++++--------------------
>> 1 file changed, 11 insertions(+), 23 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/sun/cassini.c
>> b/drivers/net/ethernet/sun/cassini.c index 0aca193..2f66cfc 100644
>> --- a/drivers/net/ethernet/sun/cassini.c
>> +++ b/drivers/net/ethernet/sun/cassini.c
>> @@ -1915,7 +1915,7 @@ static int cas_rx_process_pkt(struct cas *cp, struct
>> cas_rx_comp *rxc, int off, swivel = RX_SWIVEL_OFF_VAL;
>> struct cas_page *page;
>> struct sk_buff *skb;
>> - void *addr, *crcaddr;
>> + void *crcaddr;
>> __sum16 csum;
>> char *p;
>>
>> @@ -1936,7 +1936,7 @@ static int cas_rx_process_pkt(struct cas *cp, struct
>> cas_rx_comp *rxc, skb_reserve(skb, swivel);
>>
>> p = skb->data;
>> - addr = crcaddr = NULL;
>> + crcaddr = NULL;
>> if (hlen) { /* always copy header pages */
>> i = CAS_VAL(RX_COMP2_HDR_INDEX, words[1]);
>> page = cp->rx_pages[CAS_VAL(RX_INDEX_RING, i)]
> [CAS_VAL(RX_INDEX_NUM, i)];
>> @@ -1948,12 +1948,10 @@ static int cas_rx_process_pkt(struct cas *cp, struct
>> cas_rx_comp *rxc, i += cp->crc_size;
>> dma_sync_single_for_cpu(&cp->pdev->dev, page->dma_addr +
> off,
>> i, DMA_FROM_DEVICE);
>> - addr = cas_page_map(page->buffer);
>> - memcpy(p, addr + off, i);
>> + memcpy(p, page_address(page->buffer) + off, i);
>> dma_sync_single_for_device(&cp->pdev->dev,
>> page->dma_addr + off, i,
>> DMA_FROM_DEVICE);
>> - cas_page_unmap(addr);
>> RX_USED_ADD(page, 0x100);
>> p += hlen;
>> swivel = 0;
>> @@ -1984,12 +1982,11 @@ static int cas_rx_process_pkt(struct cas *cp, struct
>> cas_rx_comp *rxc, /* make sure we always copy a header */
>> swivel = 0;
>> if (p == (char *) skb->data) { /* not split */
>> - addr = cas_page_map(page->buffer);
>> - memcpy(p, addr + off, RX_COPY_MIN);
>> + memcpy(p, page_address(page->buffer) + off,
>> + RX_COPY_MIN);
>> dma_sync_single_for_device(&cp->pdev->dev,
>> page->dma_addr
> + off, i,
>>
> DMA_FROM_DEVICE);
>> - cas_page_unmap(addr);
>> off += RX_COPY_MIN;
>> swivel = RX_COPY_MIN;
>> RX_USED_ADD(page, cp->mtu_stride);
>> @@ -2036,10 +2033,8 @@ static int cas_rx_process_pkt(struct cas *cp, struct
>> cas_rx_comp *rxc, RX_USED_ADD(page, hlen + cp->crc_size);
>> }
>>
>> - if (cp->crc_size) {
>> - addr = cas_page_map(page->buffer);
>> - crcaddr = addr + off + hlen;
>> - }
>> + if (cp->crc_size)
>> + crcaddr = page_address(page->buffer) + off +
> hlen;
>>
>> } else {
>> /* copying packet */
>> @@ -2061,12 +2056,10 @@ static int cas_rx_process_pkt(struct cas *cp, struct
>> cas_rx_comp *rxc, i += cp->crc_size;
>> dma_sync_single_for_cpu(&cp->pdev->dev, page->dma_addr +
> off,
>> i, DMA_FROM_DEVICE);
>> - addr = cas_page_map(page->buffer);
>> - memcpy(p, addr + off, i);
>> + memcpy(p, page_address(page->buffer) + off, i);
>> dma_sync_single_for_device(&cp->pdev->dev,
>> page->dma_addr + off, i,
>> DMA_FROM_DEVICE);
>> - cas_page_unmap(addr);
>> if (p == (char *) skb->data) /* not split */
>> RX_USED_ADD(page, cp->mtu_stride);
>> else
>> @@ -2081,20 +2074,17 @@ static int cas_rx_process_pkt(struct cas *cp, struct
>> cas_rx_comp *rxc, page->dma_addr,
>> dlen + cp-
>> crc_size,
>> DMA_FROM_DEVICE);
>> - addr = cas_page_map(page->buffer);
>> - memcpy(p, addr, dlen + cp->crc_size);
>> + memcpy(p, page_address(page->buffer), dlen + cp-
>> crc_size);
>> dma_sync_single_for_device(&cp->pdev->dev,
>> page->dma_addr,
>> dlen + cp-
>> crc_size,
>>
> DMA_FROM_DEVICE);
>> - cas_page_unmap(addr);
>> RX_USED_ADD(page, dlen + cp->crc_size);
>> }
>> end_copy_pkt:
>> - if (cp->crc_size) {
>> - addr = NULL;
>> + if (cp->crc_size)
>> crcaddr = skb->data + alloclen;
>> - }
>> +
>
> This is a different logical change. Some maintainers I met would have asked
> for a separate patch, but I'm OK with it being here.
cas_page_map()/cap_page_unmap() were using addr. Once these went away
addr became unnecessary. It would be weird to leave the declaration,
init and reinit for a variable that's not of any use, and so it was
removed as well. It's cleaner this way.
Ani
next prev parent reply other threads:[~2022-11-18 17:56 UTC|newest]
Thread overview: 28+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-11-17 22:25 [PATCH net-next 0/5] Remove uses of kmap_atomic() Anirudh Venkataramanan
2022-11-17 22:25 ` [PATCH net-next 1/5] ch_ktls: Use kmap_local_page() instead " Anirudh Venkataramanan
2022-11-18 8:14 ` Fabio M. De Francesco
2022-11-18 18:27 ` Anirudh Venkataramanan
2022-11-18 20:18 ` Fabio M. De Francesco
2022-11-18 20:38 ` Anirudh Venkataramanan
2022-11-19 1:22 ` Ira Weiny
2022-11-17 22:25 ` [PATCH net-next 2/5] sfc: " Anirudh Venkataramanan
2022-11-18 8:23 ` Fabio M. De Francesco
2022-11-18 17:47 ` Anirudh Venkataramanan
2022-11-18 19:26 ` Fabio M. De Francesco
2022-11-18 20:34 ` Anirudh Venkataramanan
2022-11-19 1:25 ` Ira Weiny
2022-11-17 22:25 ` [PATCH net-next 3/5] cassini: Remove unnecessary use " Anirudh Venkataramanan
2022-11-18 8:35 ` Fabio M. De Francesco
2022-11-18 17:55 ` Anirudh Venkataramanan [this message]
2022-11-18 20:30 ` Fabio M. De Francesco
2022-11-17 22:25 ` [PATCH net-next 4/5] cassini: Use kmap_local_page() instead " Anirudh Venkataramanan
2022-11-18 8:53 ` Fabio M. De Francesco
2022-11-17 22:25 ` [PATCH net-next 5/5] sunvnet: " Anirudh Venkataramanan
2022-11-18 9:11 ` Fabio M. De Francesco
2022-11-18 20:45 ` Fabio M. De Francesco
2022-11-19 0:47 ` Anirudh Venkataramanan
2022-11-22 11:29 ` [PATCH net-next 0/5] Remove uses " Leon Romanovsky
2022-11-22 18:50 ` Jakub Kicinski
2022-11-22 21:06 ` Anirudh Venkataramanan
2022-11-23 7:34 ` Leon Romanovsky
2022-11-23 18:38 ` Anirudh Venkataramanan
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=d9a3d57b-e72c-8f8f-b4ae-979836d87d32@intel.com \
--to=anirudh.venkataramanan@intel.com \
--cc=fmdefrancesco@gmail.com \
--cc=ira.weiny@intel.com \
--cc=netdev@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).