Please include Thomas in this. On Wed, Nov 09, 2016 at 10:46:21AM +0200, Horia Geantă wrote: > This reverts commit 66d2e2028091a074aa1290d2eeda5ddb1a6c329c. > > Quoting from Russell's findings: > https://www.mail-archive.com/linux-crypto@xxxxxxxxxxxxxxx/msg21136.html > > [quote] > Okay, I've re-tested, using a different way of measuring, because using > openssl speed is impractical for off-loaded engines. I've decided to > use this way to measure the performance: > > dd if=/dev/zero bs=1048576 count=128 | /usr/bin/time openssl dgst -md5 > > For the threaded IRQs case gives: > > 0.05user 2.74system 0:05.30elapsed 52%CPU (0avgtext+0avgdata 2400maxresident)k > 0.06user 2.52system 0:05.18elapsed 49%CPU (0avgtext+0avgdata 2404maxresident)k > 0.12user 2.60system 0:05.61elapsed 48%CPU (0avgtext+0avgdata 2460maxresident)k > => 5.36s => 25.0MB/s > > and the tasklet case: > > 0.08user 2.53system 0:04.83elapsed 54%CPU (0avgtext+0avgdata 2468maxresident)k > 0.09user 2.47system 0:05.16elapsed 49%CPU (0avgtext+0avgdata 2368maxresident)k > 0.10user 2.51system 0:04.87elapsed 53%CPU (0avgtext+0avgdata 2460maxresident)k > => 4.95 => 27.1MB/s > > which corresponds to an 8% slowdown for the threaded IRQ case. So, > tasklets are indeed faster than threaded IRQs. > > [...] > > I think I've proven from the above that this patch needs to be reverted > due to the performance regression, and that there _is_ most definitely > a deterimental effect of switching from tasklets to threaded IRQs. > [/quote] > > Signed-off-by: Horia Geantă <horia.geanta@xxxxxxx> > --- > drivers/crypto/caam/intern.h | 1 + > drivers/crypto/caam/jr.c | 25 ++++++++++++++++--------- > 2 files changed, 17 insertions(+), 9 deletions(-) > > diff --git a/drivers/crypto/caam/intern.h b/drivers/crypto/caam/intern.h > index 5d4c05074a5c..e2bcacc1a921 100644 > --- a/drivers/crypto/caam/intern.h > +++ b/drivers/crypto/caam/intern.h > @@ -41,6 +41,7 @@ struct caam_drv_private_jr { > struct device *dev; > int ridx; > struct caam_job_ring __iomem *rregs; /* JobR's register space */ > + struct tasklet_struct irqtask; > int irq; /* One per queue */ > > /* Number of scatterlist crypt transforms active on the JobR */ > diff --git a/drivers/crypto/caam/jr.c b/drivers/crypto/caam/jr.c > index 7331ea734f37..c8604dfadbf5 100644 > --- a/drivers/crypto/caam/jr.c > +++ b/drivers/crypto/caam/jr.c > @@ -73,6 +73,8 @@ static int caam_jr_shutdown(struct device *dev) > > ret = caam_reset_hw_jr(dev); > > + tasklet_kill(&jrp->irqtask); > + > /* Release interrupt */ > free_irq(jrp->irq, dev); > > @@ -128,7 +130,7 @@ static irqreturn_t caam_jr_interrupt(int irq, void *st_dev) > > /* > * Check the output ring for ready responses, kick > - * the threaded irq if jobs done. > + * tasklet if jobs done. > */ > irqstate = rd_reg32(&jrp->rregs->jrintstatus); > if (!irqstate) > @@ -150,13 +152,18 @@ static irqreturn_t caam_jr_interrupt(int irq, void *st_dev) > /* Have valid interrupt at this point, just ACK and trigger */ > wr_reg32(&jrp->rregs->jrintstatus, irqstate); > > - return IRQ_WAKE_THREAD; > + preempt_disable(); > + tasklet_schedule(&jrp->irqtask); > + preempt_enable(); > + > + return IRQ_HANDLED; > } > > -static irqreturn_t caam_jr_threadirq(int irq, void *st_dev) > +/* Deferred service handler, run as interrupt-fired tasklet */ > +static void caam_jr_dequeue(unsigned long devarg) > { > int hw_idx, sw_idx, i, head, tail; > - struct device *dev = st_dev; > + struct device *dev = (struct device *)devarg; > struct caam_drv_private_jr *jrp = dev_get_drvdata(dev); > void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg); > u32 *userdesc, userstatus; > @@ -230,8 +237,6 @@ static irqreturn_t caam_jr_threadirq(int irq, void *st_dev) > > /* reenable / unmask IRQs */ > clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0); > - > - return IRQ_HANDLED; > } > > /** > @@ -389,10 +394,11 @@ static int caam_jr_init(struct device *dev) > > jrp = dev_get_drvdata(dev); > > + tasklet_init(&jrp->irqtask, caam_jr_dequeue, (unsigned long)dev); > + > /* Connect job ring interrupt handler. */ > - error = request_threaded_irq(jrp->irq, caam_jr_interrupt, > - caam_jr_threadirq, IRQF_SHARED, > - dev_name(dev), dev); > + error = request_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED, > + dev_name(dev), dev); > if (error) { > dev_err(dev, "can't connect JobR %d interrupt (%d)\n", > jrp->ridx, jrp->irq); > @@ -454,6 +460,7 @@ static int caam_jr_init(struct device *dev) > out_free_irq: > free_irq(jrp->irq, dev); > out_kill_deq: > + tasklet_kill(&jrp->irqtask); > return error; > } > > -- > 2.4.4 > -- RMK's Patch system: http://www.armlinux.org.uk/developer/patches/ FTTC broadband for 0.8mile line: currently at 9.6Mbps down 400kbps up according to speedtest.net. -- To unsubscribe from this list: send the line "unsubscribe linux-crypto" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
