mirror of
https://github.com/torvalds/linux.git
synced 2024-11-18 10:01:43 +00:00
f5bd91388e
XSK UMEM is strongly single producer single consumer so reuse of frames is challenging. Add a simple "stash" of FILL packets to reuse for drivers to optionally make use of. This is useful when driver has to free (ndo_stop) or resize a ring with an active AF_XDP ZC socket. Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com> Tested-by: Andrew Bowers <andrewx.bowers@intel.com> Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
120 lines
2.4 KiB
C
120 lines
2.4 KiB
C
// SPDX-License-Identifier: GPL-2.0
|
|
/* XDP user-space ring structure
|
|
* Copyright(c) 2018 Intel Corporation.
|
|
*/
|
|
|
|
#include <linux/log2.h>
|
|
#include <linux/slab.h>
|
|
#include <linux/overflow.h>
|
|
|
|
#include "xsk_queue.h"
|
|
|
|
void xskq_set_umem(struct xsk_queue *q, u64 size, u64 chunk_mask)
|
|
{
|
|
if (!q)
|
|
return;
|
|
|
|
q->size = size;
|
|
q->chunk_mask = chunk_mask;
|
|
}
|
|
|
|
static u32 xskq_umem_get_ring_size(struct xsk_queue *q)
|
|
{
|
|
return sizeof(struct xdp_umem_ring) + q->nentries * sizeof(u64);
|
|
}
|
|
|
|
static u32 xskq_rxtx_get_ring_size(struct xsk_queue *q)
|
|
{
|
|
return sizeof(struct xdp_ring) + q->nentries * sizeof(struct xdp_desc);
|
|
}
|
|
|
|
struct xsk_queue *xskq_create(u32 nentries, bool umem_queue)
|
|
{
|
|
struct xsk_queue *q;
|
|
gfp_t gfp_flags;
|
|
size_t size;
|
|
|
|
q = kzalloc(sizeof(*q), GFP_KERNEL);
|
|
if (!q)
|
|
return NULL;
|
|
|
|
q->nentries = nentries;
|
|
q->ring_mask = nentries - 1;
|
|
|
|
gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN |
|
|
__GFP_COMP | __GFP_NORETRY;
|
|
size = umem_queue ? xskq_umem_get_ring_size(q) :
|
|
xskq_rxtx_get_ring_size(q);
|
|
|
|
q->ring = (struct xdp_ring *)__get_free_pages(gfp_flags,
|
|
get_order(size));
|
|
if (!q->ring) {
|
|
kfree(q);
|
|
return NULL;
|
|
}
|
|
|
|
return q;
|
|
}
|
|
|
|
void xskq_destroy(struct xsk_queue *q)
|
|
{
|
|
if (!q)
|
|
return;
|
|
|
|
page_frag_free(q->ring);
|
|
kfree(q);
|
|
}
|
|
|
|
struct xdp_umem_fq_reuse *xsk_reuseq_prepare(u32 nentries)
|
|
{
|
|
struct xdp_umem_fq_reuse *newq;
|
|
|
|
/* Check for overflow */
|
|
if (nentries > (u32)roundup_pow_of_two(nentries))
|
|
return NULL;
|
|
nentries = roundup_pow_of_two(nentries);
|
|
|
|
newq = kvmalloc(struct_size(newq, handles, nentries), GFP_KERNEL);
|
|
if (!newq)
|
|
return NULL;
|
|
memset(newq, 0, offsetof(typeof(*newq), handles));
|
|
|
|
newq->nentries = nentries;
|
|
return newq;
|
|
}
|
|
EXPORT_SYMBOL_GPL(xsk_reuseq_prepare);
|
|
|
|
struct xdp_umem_fq_reuse *xsk_reuseq_swap(struct xdp_umem *umem,
|
|
struct xdp_umem_fq_reuse *newq)
|
|
{
|
|
struct xdp_umem_fq_reuse *oldq = umem->fq_reuse;
|
|
|
|
if (!oldq) {
|
|
umem->fq_reuse = newq;
|
|
return NULL;
|
|
}
|
|
|
|
if (newq->nentries < oldq->length)
|
|
return newq;
|
|
|
|
memcpy(newq->handles, oldq->handles,
|
|
array_size(oldq->length, sizeof(u64)));
|
|
newq->length = oldq->length;
|
|
|
|
umem->fq_reuse = newq;
|
|
return oldq;
|
|
}
|
|
EXPORT_SYMBOL_GPL(xsk_reuseq_swap);
|
|
|
|
void xsk_reuseq_free(struct xdp_umem_fq_reuse *rq)
|
|
{
|
|
kvfree(rq);
|
|
}
|
|
EXPORT_SYMBOL_GPL(xsk_reuseq_free);
|
|
|
|
void xsk_reuseq_destroy(struct xdp_umem *umem)
|
|
{
|
|
xsk_reuseq_free(umem->fq_reuse);
|
|
umem->fq_reuse = NULL;
|
|
}
|