diff options
| author | Russell King <rmk+kernel@arm.linux.org.uk> | 2016-08-08 20:05:24 +0300 |
|---|---|---|
| committer | Herbert Xu <herbert@gondor.apana.org.au> | 2016-08-09 13:47:28 +0300 |
| commit | 66d2e2028091a074aa1290d2eeda5ddb1a6c329c (patch) | |
| tree | a5decf16bd35101d031defcce9f9c095649c4e33 /drivers/crypto | |
| parent | 65cf164a4afab86b9d26c063bc4cef5432b52021 (diff) | |
| download | linux-66d2e2028091a074aa1290d2eeda5ddb1a6c329c.tar.xz | |
crypto: caam - get rid of tasklet
Threaded interrupts can perform the function of the tasklet, and much
more safely too - without races when trying to take the tasklet and
interrupt down on device removal.
With the old code, there is a window where we call tasklet_kill(). If
the interrupt handler happens to be running on a different CPU, and
subsequently calls tasklet_schedule(), the tasklet will be re-scheduled
for execution.
Switching to a hardirq/threadirq combination implementation avoids this,
and it also means generic code deals with the teardown sequencing of the
threaded and non-threaded parts.
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'drivers/crypto')
| -rw-r--r-- | drivers/crypto/caam/intern.h | 1 | ||||
| -rw-r--r-- | drivers/crypto/caam/jr.c | 25 |
2 files changed, 9 insertions, 17 deletions
diff --git a/drivers/crypto/caam/intern.h b/drivers/crypto/caam/intern.h index e2bcacc1a921..5d4c05074a5c 100644 --- a/drivers/crypto/caam/intern.h +++ b/drivers/crypto/caam/intern.h @@ -41,7 +41,6 @@ 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 a81f551ac222..320228875e9a 100644 --- a/drivers/crypto/caam/jr.c +++ b/drivers/crypto/caam/jr.c @@ -73,8 +73,6 @@ 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); @@ -130,7 +128,7 @@ static irqreturn_t caam_jr_interrupt(int irq, void *st_dev) /* * Check the output ring for ready responses, kick - * tasklet if jobs done. + * the threaded irq if jobs done. */ irqstate = rd_reg32(&jrp->rregs->jrintstatus); if (!irqstate) @@ -152,18 +150,13 @@ 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); - preempt_disable(); - tasklet_schedule(&jrp->irqtask); - preempt_enable(); - - return IRQ_HANDLED; + return IRQ_WAKE_THREAD; } -/* Deferred service handler, run as interrupt-fired tasklet */ -static void caam_jr_dequeue(unsigned long devarg) +static irqreturn_t caam_jr_threadirq(int irq, void *st_dev) { int hw_idx, sw_idx, i, head, tail; - struct device *dev = (struct device *)devarg; + struct device *dev = st_dev; struct caam_drv_private_jr *jrp = dev_get_drvdata(dev); void (*usercall)(struct device *dev, u32 *desc, u32 status, void *arg); u32 *userdesc, userstatus; @@ -237,6 +230,8 @@ static void caam_jr_dequeue(unsigned long devarg) /* reenable / unmask IRQs */ clrsetbits_32(&jrp->rregs->rconfig_lo, JRCFG_IMSK, 0); + + return IRQ_HANDLED; } /** @@ -394,11 +389,10 @@ 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_irq(jrp->irq, caam_jr_interrupt, IRQF_SHARED, - dev_name(dev), dev); + error = request_threaded_irq(jrp->irq, caam_jr_interrupt, + caam_jr_threadirq, IRQF_SHARED, + dev_name(dev), dev); if (error) { dev_err(dev, "can't connect JobR %d interrupt (%d)\n", jrp->ridx, jrp->irq); @@ -460,7 +454,6 @@ out_free_inpring: out_free_irq: free_irq(jrp->irq, dev); out_kill_deq: - tasklet_kill(&jrp->irqtask); return error; } |