kernel_optimize_test/drivers/scsi/fnic/fnic_isr.c
Abhijeet Joglekar d5cf4b28e1 [SCSI] fnic: Process all cq entries per ISR
Driver was processing a fixed max number of cq descriptors per ISR. For
instance, for the SCSI IO queue, number of IOs processed per ISR were 8.
If hardware writes 9 cq descriptors to the cq and generates an interrupt,
driver would process only 8 descriptors and decrement the outstanding
credit count by 8. Unless another interrupt event happens, the hw does
not generate any additional interrupt. This results in the cq descriptor
sitting in the queue without being procesed and can cause IO timeouts
and aborts.

Modify all ISR functions to process all queued cq descriptors in one shot.
Since bulk of ELS frame processing is done in thread context and bulk
of SCSI IO processing is done in soft ISR deferred context, the cycles
spent in the ISR per cq descriptor is small.

Signed-off-by: Herman Lee <hermlee@cisco.com>
Signed-off-by: Abhijeet Joglekar <abjoglek@cisco.com>
Signed-off-by: Robert Love <robert.w.love@intel.com>
Signed-off-by: James Bottomley <James.Bottomley@suse.de>
2009-12-04 12:00:35 -06:00

333 lines
8.1 KiB
C

/*
* Copyright 2008 Cisco Systems, Inc. All rights reserved.
* Copyright 2007 Nuova Systems, Inc. All rights reserved.
*
* This program is free software; you may redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; version 2 of the License.
*
* 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/string.h>
#include <linux/errno.h>
#include <linux/pci.h>
#include <linux/interrupt.h>
#include <scsi/libfc.h>
#include <scsi/fc_frame.h>
#include "vnic_dev.h"
#include "vnic_intr.h"
#include "vnic_stats.h"
#include "fnic_io.h"
#include "fnic.h"
static irqreturn_t fnic_isr_legacy(int irq, void *data)
{
struct fnic *fnic = data;
u32 pba;
unsigned long work_done = 0;
pba = vnic_intr_legacy_pba(fnic->legacy_pba);
if (!pba)
return IRQ_NONE;
if (pba & (1 << FNIC_INTX_NOTIFY)) {
vnic_intr_return_all_credits(&fnic->intr[FNIC_INTX_NOTIFY]);
fnic_handle_link_event(fnic);
}
if (pba & (1 << FNIC_INTX_ERR)) {
vnic_intr_return_all_credits(&fnic->intr[FNIC_INTX_ERR]);
fnic_log_q_error(fnic);
}
if (pba & (1 << FNIC_INTX_WQ_RQ_COPYWQ)) {
work_done += fnic_wq_copy_cmpl_handler(fnic, -1);
work_done += fnic_wq_cmpl_handler(fnic, -1);
work_done += fnic_rq_cmpl_handler(fnic, -1);
vnic_intr_return_credits(&fnic->intr[FNIC_INTX_WQ_RQ_COPYWQ],
work_done,
1 /* unmask intr */,
1 /* reset intr timer */);
}
return IRQ_HANDLED;
}
static irqreturn_t fnic_isr_msi(int irq, void *data)
{
struct fnic *fnic = data;
unsigned long work_done = 0;
work_done += fnic_wq_copy_cmpl_handler(fnic, -1);
work_done += fnic_wq_cmpl_handler(fnic, -1);
work_done += fnic_rq_cmpl_handler(fnic, -1);
vnic_intr_return_credits(&fnic->intr[0],
work_done,
1 /* unmask intr */,
1 /* reset intr timer */);
return IRQ_HANDLED;
}
static irqreturn_t fnic_isr_msix_rq(int irq, void *data)
{
struct fnic *fnic = data;
unsigned long rq_work_done = 0;
rq_work_done = fnic_rq_cmpl_handler(fnic, -1);
vnic_intr_return_credits(&fnic->intr[FNIC_MSIX_RQ],
rq_work_done,
1 /* unmask intr */,
1 /* reset intr timer */);
return IRQ_HANDLED;
}
static irqreturn_t fnic_isr_msix_wq(int irq, void *data)
{
struct fnic *fnic = data;
unsigned long wq_work_done = 0;
wq_work_done = fnic_wq_cmpl_handler(fnic, -1);
vnic_intr_return_credits(&fnic->intr[FNIC_MSIX_WQ],
wq_work_done,
1 /* unmask intr */,
1 /* reset intr timer */);
return IRQ_HANDLED;
}
static irqreturn_t fnic_isr_msix_wq_copy(int irq, void *data)
{
struct fnic *fnic = data;
unsigned long wq_copy_work_done = 0;
wq_copy_work_done = fnic_wq_copy_cmpl_handler(fnic, -1);
vnic_intr_return_credits(&fnic->intr[FNIC_MSIX_WQ_COPY],
wq_copy_work_done,
1 /* unmask intr */,
1 /* reset intr timer */);
return IRQ_HANDLED;
}
static irqreturn_t fnic_isr_msix_err_notify(int irq, void *data)
{
struct fnic *fnic = data;
vnic_intr_return_all_credits(&fnic->intr[FNIC_MSIX_ERR_NOTIFY]);
fnic_log_q_error(fnic);
fnic_handle_link_event(fnic);
return IRQ_HANDLED;
}
void fnic_free_intr(struct fnic *fnic)
{
int i;
switch (vnic_dev_get_intr_mode(fnic->vdev)) {
case VNIC_DEV_INTR_MODE_INTX:
case VNIC_DEV_INTR_MODE_MSI:
free_irq(fnic->pdev->irq, fnic);
break;
case VNIC_DEV_INTR_MODE_MSIX:
for (i = 0; i < ARRAY_SIZE(fnic->msix); i++)
if (fnic->msix[i].requested)
free_irq(fnic->msix_entry[i].vector,
fnic->msix[i].devid);
break;
default:
break;
}
}
int fnic_request_intr(struct fnic *fnic)
{
int err = 0;
int i;
switch (vnic_dev_get_intr_mode(fnic->vdev)) {
case VNIC_DEV_INTR_MODE_INTX:
err = request_irq(fnic->pdev->irq, &fnic_isr_legacy,
IRQF_SHARED, DRV_NAME, fnic);
break;
case VNIC_DEV_INTR_MODE_MSI:
err = request_irq(fnic->pdev->irq, &fnic_isr_msi,
0, fnic->name, fnic);
break;
case VNIC_DEV_INTR_MODE_MSIX:
sprintf(fnic->msix[FNIC_MSIX_RQ].devname,
"%.11s-fcs-rq", fnic->name);
fnic->msix[FNIC_MSIX_RQ].isr = fnic_isr_msix_rq;
fnic->msix[FNIC_MSIX_RQ].devid = fnic;
sprintf(fnic->msix[FNIC_MSIX_WQ].devname,
"%.11s-fcs-wq", fnic->name);
fnic->msix[FNIC_MSIX_WQ].isr = fnic_isr_msix_wq;
fnic->msix[FNIC_MSIX_WQ].devid = fnic;
sprintf(fnic->msix[FNIC_MSIX_WQ_COPY].devname,
"%.11s-scsi-wq", fnic->name);
fnic->msix[FNIC_MSIX_WQ_COPY].isr = fnic_isr_msix_wq_copy;
fnic->msix[FNIC_MSIX_WQ_COPY].devid = fnic;
sprintf(fnic->msix[FNIC_MSIX_ERR_NOTIFY].devname,
"%.11s-err-notify", fnic->name);
fnic->msix[FNIC_MSIX_ERR_NOTIFY].isr =
fnic_isr_msix_err_notify;
fnic->msix[FNIC_MSIX_ERR_NOTIFY].devid = fnic;
for (i = 0; i < ARRAY_SIZE(fnic->msix); i++) {
err = request_irq(fnic->msix_entry[i].vector,
fnic->msix[i].isr, 0,
fnic->msix[i].devname,
fnic->msix[i].devid);
if (err) {
shost_printk(KERN_ERR, fnic->lport->host,
"MSIX: request_irq"
" failed %d\n", err);
fnic_free_intr(fnic);
break;
}
fnic->msix[i].requested = 1;
}
break;
default:
break;
}
return err;
}
int fnic_set_intr_mode(struct fnic *fnic)
{
unsigned int n = ARRAY_SIZE(fnic->rq);
unsigned int m = ARRAY_SIZE(fnic->wq);
unsigned int o = ARRAY_SIZE(fnic->wq_copy);
unsigned int i;
/*
* Set interrupt mode (INTx, MSI, MSI-X) depending
* system capabilities.
*
* Try MSI-X first
*
* We need n RQs, m WQs, o Copy WQs, n+m+o CQs, and n+m+o+1 INTRs
* (last INTR is used for WQ/RQ errors and notification area)
*/
BUG_ON(ARRAY_SIZE(fnic->msix_entry) < n + m + o + 1);
for (i = 0; i < n + m + o + 1; i++)
fnic->msix_entry[i].entry = i;
if (fnic->rq_count >= n &&
fnic->raw_wq_count >= m &&
fnic->wq_copy_count >= o &&
fnic->cq_count >= n + m + o) {
if (!pci_enable_msix(fnic->pdev, fnic->msix_entry,
n + m + o + 1)) {
fnic->rq_count = n;
fnic->raw_wq_count = m;
fnic->wq_copy_count = o;
fnic->wq_count = m + o;
fnic->cq_count = n + m + o;
fnic->intr_count = n + m + o + 1;
fnic->err_intr_offset = FNIC_MSIX_ERR_NOTIFY;
FNIC_ISR_DBG(KERN_DEBUG, fnic->lport->host,
"Using MSI-X Interrupts\n");
vnic_dev_set_intr_mode(fnic->vdev,
VNIC_DEV_INTR_MODE_MSIX);
return 0;
}
}
/*
* Next try MSI
* We need 1 RQ, 1 WQ, 1 WQ_COPY, 3 CQs, and 1 INTR
*/
if (fnic->rq_count >= 1 &&
fnic->raw_wq_count >= 1 &&
fnic->wq_copy_count >= 1 &&
fnic->cq_count >= 3 &&
fnic->intr_count >= 1 &&
!pci_enable_msi(fnic->pdev)) {
fnic->rq_count = 1;
fnic->raw_wq_count = 1;
fnic->wq_copy_count = 1;
fnic->wq_count = 2;
fnic->cq_count = 3;
fnic->intr_count = 1;
fnic->err_intr_offset = 0;
FNIC_ISR_DBG(KERN_DEBUG, fnic->lport->host,
"Using MSI Interrupts\n");
vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_MSI);
return 0;
}
/*
* Next try INTx
* We need 1 RQ, 1 WQ, 1 WQ_COPY, 3 CQs, and 3 INTRs
* 1 INTR is used for all 3 queues, 1 INTR for queue errors
* 1 INTR for notification area
*/
if (fnic->rq_count >= 1 &&
fnic->raw_wq_count >= 1 &&
fnic->wq_copy_count >= 1 &&
fnic->cq_count >= 3 &&
fnic->intr_count >= 3) {
fnic->rq_count = 1;
fnic->raw_wq_count = 1;
fnic->wq_copy_count = 1;
fnic->cq_count = 3;
fnic->intr_count = 3;
FNIC_ISR_DBG(KERN_DEBUG, fnic->lport->host,
"Using Legacy Interrupts\n");
vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_INTX);
return 0;
}
vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_UNKNOWN);
return -EINVAL;
}
void fnic_clear_intr_mode(struct fnic *fnic)
{
switch (vnic_dev_get_intr_mode(fnic->vdev)) {
case VNIC_DEV_INTR_MODE_MSIX:
pci_disable_msix(fnic->pdev);
break;
case VNIC_DEV_INTR_MODE_MSI:
pci_disable_msi(fnic->pdev);
break;
default:
break;
}
vnic_dev_set_intr_mode(fnic->vdev, VNIC_DEV_INTR_MODE_INTX);
}