diff options
author | Jakub Kicinski <jakub.kicinski@netronome.com> | 2018-09-07 10:18:46 +0200 |
---|---|---|
committer | Jeff Kirsher <jeffrey.t.kirsher@intel.com> | 2018-09-25 13:13:15 -0700 |
commit | f5bd91388e26557f64ca999e0006038c7a919308 (patch) | |
tree | 28d868b5c3ed674e3bc2e18cd179657d4301bd9d /net/xdp | |
parent | 9dbb137045774f66d036ce3bcdd3f36b9401f8d4 (diff) |
net: xsk: add a simple buffer reuse queue
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>
Diffstat (limited to 'net/xdp')
-rw-r--r-- | net/xdp/xdp_umem.c | 2 | ||||
-rw-r--r-- | net/xdp/xsk_queue.c | 55 | ||||
-rw-r--r-- | net/xdp/xsk_queue.h | 3 |
3 files changed, 60 insertions, 0 deletions
diff --git a/net/xdp/xdp_umem.c b/net/xdp/xdp_umem.c index b3b632c5aeae..555427b3e0fe 100644 --- a/net/xdp/xdp_umem.c +++ b/net/xdp/xdp_umem.c @@ -165,6 +165,8 @@ static void xdp_umem_release(struct xdp_umem *umem) umem->cq = NULL; } + xsk_reuseq_destroy(umem); + xdp_umem_unpin_pages(umem); task = get_pid_task(umem->pid, PIDTYPE_PID); diff --git a/net/xdp/xsk_queue.c b/net/xdp/xsk_queue.c index 2dc1384d9f27..b66504592d9b 100644 --- a/net/xdp/xsk_queue.c +++ b/net/xdp/xsk_queue.c @@ -3,7 +3,9 @@ * Copyright(c) 2018 Intel Corporation. */ +#include <linux/log2.h> #include <linux/slab.h> +#include <linux/overflow.h> #include "xsk_queue.h" @@ -62,3 +64,56 @@ void xskq_destroy(struct xsk_queue *q) 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; +} diff --git a/net/xdp/xsk_queue.h b/net/xdp/xsk_queue.h index 82252cccb4e0..bcb5cbb40419 100644 --- a/net/xdp/xsk_queue.h +++ b/net/xdp/xsk_queue.h @@ -258,4 +258,7 @@ void xskq_set_umem(struct xsk_queue *q, u64 size, u64 chunk_mask); struct xsk_queue *xskq_create(u32 nentries, bool umem_queue); void xskq_destroy(struct xsk_queue *q_ops); +/* Executed by the core when the entire UMEM gets freed */ +void xsk_reuseq_destroy(struct xdp_umem *umem); + #endif /* _LINUX_XSK_QUEUE_H */ |