linux_dsm_epyc7002/drivers/infiniband/hw/ipath/ipath_srq.c
Ralph Campbell 373d991580 IB/ipath: Performance improvements via mmap of queues
Improve performance of userspace post receive, post SRQ receive, and
poll CQ operations for ipath by allowing userspace to directly mmap()
receive queues and completion queues.  This eliminates the copying
between userspace and the kernel in the data path.

Signed-off-by: Ralph Campbell <ralph.campbell@qlogic.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>
2006-09-22 15:22:26 -07:00

360 lines
8.6 KiB
C

/*
* Copyright (c) 2006 QLogic, Inc. All rights reserved.
* Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
*
* This software is available to you under a choice of one of two
* licenses. You may choose to be licensed under the terms of the GNU
* General Public License (GPL) Version 2, available from the file
* COPYING in the main directory of this source tree, or the
* OpenIB.org BSD license below:
*
* Redistribution and use in source and binary forms, with or
* without modification, are permitted provided that the following
* conditions are met:
*
* - Redistributions of source code must retain the above
* copyright notice, this list of conditions and the following
* disclaimer.
*
* - Redistributions in binary form must reproduce the above
* copyright notice, this list of conditions and the following
* disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
#include <linux/err.h>
#include <linux/vmalloc.h>
#include "ipath_verbs.h"
/**
* ipath_post_srq_receive - post a receive on a shared receive queue
* @ibsrq: the SRQ to post the receive on
* @wr: the list of work requests to post
* @bad_wr: the first WR to cause a problem is put here
*
* This may be called from interrupt context.
*/
int ipath_post_srq_receive(struct ib_srq *ibsrq, struct ib_recv_wr *wr,
struct ib_recv_wr **bad_wr)
{
struct ipath_srq *srq = to_isrq(ibsrq);
struct ipath_rwq *wq;
unsigned long flags;
int ret;
for (; wr; wr = wr->next) {
struct ipath_rwqe *wqe;
u32 next;
int i;
if ((unsigned) wr->num_sge > srq->rq.max_sge) {
*bad_wr = wr;
ret = -ENOMEM;
goto bail;
}
spin_lock_irqsave(&srq->rq.lock, flags);
wq = srq->rq.wq;
next = wq->head + 1;
if (next >= srq->rq.size)
next = 0;
if (next == wq->tail) {
spin_unlock_irqrestore(&srq->rq.lock, flags);
*bad_wr = wr;
ret = -ENOMEM;
goto bail;
}
wqe = get_rwqe_ptr(&srq->rq, wq->head);
wqe->wr_id = wr->wr_id;
wqe->num_sge = wr->num_sge;
for (i = 0; i < wr->num_sge; i++)
wqe->sg_list[i] = wr->sg_list[i];
wq->head = next;
spin_unlock_irqrestore(&srq->rq.lock, flags);
}
ret = 0;
bail:
return ret;
}
/**
* ipath_create_srq - create a shared receive queue
* @ibpd: the protection domain of the SRQ to create
* @attr: the attributes of the SRQ
* @udata: not used by the InfiniPath verbs driver
*/
struct ib_srq *ipath_create_srq(struct ib_pd *ibpd,
struct ib_srq_init_attr *srq_init_attr,
struct ib_udata *udata)
{
struct ipath_ibdev *dev = to_idev(ibpd->device);
struct ipath_srq *srq;
u32 sz;
struct ib_srq *ret;
if (dev->n_srqs_allocated == ib_ipath_max_srqs) {
ret = ERR_PTR(-ENOMEM);
goto done;
}
if (srq_init_attr->attr.max_wr == 0) {
ret = ERR_PTR(-EINVAL);
goto done;
}
if ((srq_init_attr->attr.max_sge > ib_ipath_max_srq_sges) ||
(srq_init_attr->attr.max_wr > ib_ipath_max_srq_wrs)) {
ret = ERR_PTR(-EINVAL);
goto done;
}
srq = kmalloc(sizeof(*srq), GFP_KERNEL);
if (!srq) {
ret = ERR_PTR(-ENOMEM);
goto done;
}
/*
* Need to use vmalloc() if we want to support large #s of entries.
*/
srq->rq.size = srq_init_attr->attr.max_wr + 1;
srq->rq.max_sge = srq_init_attr->attr.max_sge;
sz = sizeof(struct ib_sge) * srq->rq.max_sge +
sizeof(struct ipath_rwqe);
srq->rq.wq = vmalloc_user(sizeof(struct ipath_rwq) + srq->rq.size * sz);
if (!srq->rq.wq) {
ret = ERR_PTR(-ENOMEM);
goto bail_srq;
}
/*
* Return the address of the RWQ as the offset to mmap.
* See ipath_mmap() for details.
*/
if (udata && udata->outlen >= sizeof(__u64)) {
struct ipath_mmap_info *ip;
__u64 offset = (__u64) srq->rq.wq;
int err;
err = ib_copy_to_udata(udata, &offset, sizeof(offset));
if (err) {
ret = ERR_PTR(err);
goto bail_wq;
}
/* Allocate info for ipath_mmap(). */
ip = kmalloc(sizeof(*ip), GFP_KERNEL);
if (!ip) {
ret = ERR_PTR(-ENOMEM);
goto bail_wq;
}
srq->ip = ip;
ip->context = ibpd->uobject->context;
ip->obj = srq->rq.wq;
kref_init(&ip->ref);
ip->mmap_cnt = 0;
ip->size = PAGE_ALIGN(sizeof(struct ipath_rwq) +
srq->rq.size * sz);
spin_lock_irq(&dev->pending_lock);
ip->next = dev->pending_mmaps;
dev->pending_mmaps = ip;
spin_unlock_irq(&dev->pending_lock);
} else
srq->ip = NULL;
/*
* ib_create_srq() will initialize srq->ibsrq.
*/
spin_lock_init(&srq->rq.lock);
srq->rq.wq->head = 0;
srq->rq.wq->tail = 0;
srq->rq.max_sge = srq_init_attr->attr.max_sge;
srq->limit = srq_init_attr->attr.srq_limit;
dev->n_srqs_allocated++;
ret = &srq->ibsrq;
goto done;
bail_wq:
vfree(srq->rq.wq);
bail_srq:
kfree(srq);
done:
return ret;
}
/**
* ipath_modify_srq - modify a shared receive queue
* @ibsrq: the SRQ to modify
* @attr: the new attributes of the SRQ
* @attr_mask: indicates which attributes to modify
* @udata: user data for ipathverbs.so
*/
int ipath_modify_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr,
enum ib_srq_attr_mask attr_mask,
struct ib_udata *udata)
{
struct ipath_srq *srq = to_isrq(ibsrq);
int ret = 0;
if (attr_mask & IB_SRQ_MAX_WR) {
struct ipath_rwq *owq;
struct ipath_rwq *wq;
struct ipath_rwqe *p;
u32 sz, size, n, head, tail;
/* Check that the requested sizes are below the limits. */
if ((attr->max_wr > ib_ipath_max_srq_wrs) ||
((attr_mask & IB_SRQ_LIMIT) ?
attr->srq_limit : srq->limit) > attr->max_wr) {
ret = -EINVAL;
goto bail;
}
sz = sizeof(struct ipath_rwqe) +
srq->rq.max_sge * sizeof(struct ib_sge);
size = attr->max_wr + 1;
wq = vmalloc_user(sizeof(struct ipath_rwq) + size * sz);
if (!wq) {
ret = -ENOMEM;
goto bail;
}
/*
* Return the address of the RWQ as the offset to mmap.
* See ipath_mmap() for details.
*/
if (udata && udata->inlen >= sizeof(__u64)) {
__u64 offset_addr;
__u64 offset = (__u64) wq;
ret = ib_copy_from_udata(&offset_addr, udata,
sizeof(offset_addr));
if (ret) {
vfree(wq);
goto bail;
}
udata->outbuf = (void __user *) offset_addr;
ret = ib_copy_to_udata(udata, &offset,
sizeof(offset));
if (ret) {
vfree(wq);
goto bail;
}
}
spin_lock_irq(&srq->rq.lock);
/*
* validate head pointer value and compute
* the number of remaining WQEs.
*/
owq = srq->rq.wq;
head = owq->head;
if (head >= srq->rq.size)
head = 0;
tail = owq->tail;
if (tail >= srq->rq.size)
tail = 0;
n = head;
if (n < tail)
n += srq->rq.size - tail;
else
n -= tail;
if (size <= n) {
spin_unlock_irq(&srq->rq.lock);
vfree(wq);
ret = -EINVAL;
goto bail;
}
n = 0;
p = wq->wq;
while (tail != head) {
struct ipath_rwqe *wqe;
int i;
wqe = get_rwqe_ptr(&srq->rq, tail);
p->wr_id = wqe->wr_id;
p->num_sge = wqe->num_sge;
for (i = 0; i < wqe->num_sge; i++)
p->sg_list[i] = wqe->sg_list[i];
n++;
p = (struct ipath_rwqe *)((char *) p + sz);
if (++tail >= srq->rq.size)
tail = 0;
}
srq->rq.wq = wq;
srq->rq.size = size;
wq->head = n;
wq->tail = 0;
if (attr_mask & IB_SRQ_LIMIT)
srq->limit = attr->srq_limit;
spin_unlock_irq(&srq->rq.lock);
vfree(owq);
if (srq->ip) {
struct ipath_mmap_info *ip = srq->ip;
struct ipath_ibdev *dev = to_idev(srq->ibsrq.device);
ip->obj = wq;
ip->size = PAGE_ALIGN(sizeof(struct ipath_rwq) +
size * sz);
spin_lock_irq(&dev->pending_lock);
ip->next = dev->pending_mmaps;
dev->pending_mmaps = ip;
spin_unlock_irq(&dev->pending_lock);
}
} else if (attr_mask & IB_SRQ_LIMIT) {
spin_lock_irq(&srq->rq.lock);
if (attr->srq_limit >= srq->rq.size)
ret = -EINVAL;
else
srq->limit = attr->srq_limit;
spin_unlock_irq(&srq->rq.lock);
}
bail:
return ret;
}
int ipath_query_srq(struct ib_srq *ibsrq, struct ib_srq_attr *attr)
{
struct ipath_srq *srq = to_isrq(ibsrq);
attr->max_wr = srq->rq.size - 1;
attr->max_sge = srq->rq.max_sge;
attr->srq_limit = srq->limit;
return 0;
}
/**
* ipath_destroy_srq - destroy a shared receive queue
* @ibsrq: the SRQ to destroy
*/
int ipath_destroy_srq(struct ib_srq *ibsrq)
{
struct ipath_srq *srq = to_isrq(ibsrq);
struct ipath_ibdev *dev = to_idev(ibsrq->device);
dev->n_srqs_allocated--;
vfree(srq->rq.wq);
kfree(srq);
return 0;
}