Subject: [PATCH v2 net-next 3/3] crypto: caam: Replace in_irq() usage.

The driver uses in_irq() + in_serving_softirq() magic to decide if NAPI
scheduling is required or packet processing.

The usage of in_*() in drivers is phased out and Linus clearly requested
that code which changes behaviour depending on context should either be
separated or the context be conveyed in an argument passed by the caller,
which usually knows the context.

Use the `sched_napi' argument passed by the callback. It is set true if
called from the interrupt handler and NAPI should be scheduled.

Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
Cc: "Horia Geantă" <[email protected]>
Cc: Aymen Sghaier <[email protected]>
Cc: Herbert Xu <[email protected]>
Cc: "David S. Miller" <[email protected]>
Cc: Madalin Bucur <[email protected]>
Cc: Jakub Kicinski <[email protected]>
Cc: Li Yang <[email protected]>
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
Cc: [email protected]
---
drivers/crypto/caam/qi.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/crypto/caam/qi.c b/drivers/crypto/caam/qi.c
index 57f6ab6bfb56a..8163f5df8ebf7 100644
--- a/drivers/crypto/caam/qi.c
+++ b/drivers/crypto/caam/qi.c
@@ -545,14 +545,10 @@ static void cgr_cb(struct qman_portal *qm, struct qman_cgr *cgr, int congested)
}
}

-static int caam_qi_napi_schedule(struct qman_portal *p, struct caam_napi *np)
+static int caam_qi_napi_schedule(struct qman_portal *p, struct caam_napi *np,
+ bool sched_napi)
{
- /*
- * In case of threaded ISR, for RT kernels in_irq() does not return
- * appropriate value, so use in_serving_softirq to distinguish between
- * softirq and irq contexts.
- */
- if (unlikely(in_irq() || !in_serving_softirq())) {
+ if (sched_napi) {
/* Disable QMan IRQ source and invoke NAPI */
qman_p_irqsource_remove(p, QM_PIRQ_DQRI);
np->p = p;
@@ -574,7 +570,7 @@ static enum qman_cb_dqrr_result caam_rsp_fq_dqrr_cb(struct qman_portal *p,
struct caam_drv_private *priv = dev_get_drvdata(qidev);
u32 status;

- if (caam_qi_napi_schedule(p, caam_napi))
+ if (caam_qi_napi_schedule(p, caam_napi, sched_napi))
return qman_cb_dqrr_stop;

fd = &dqrr->fd;
--
2.29.1


2020-11-02 21:15:59

by Horia Geanta

[permalink] [raw]
Subject: Re: [PATCH v2 net-next 3/3] crypto: caam: Replace in_irq() usage.

On 11/2/2020 1:23 AM, Sebastian Andrzej Siewior wrote:
> The driver uses in_irq() + in_serving_softirq() magic to decide if NAPI
> scheduling is required or packet processing.
>
> The usage of in_*() in drivers is phased out and Linus clearly requested
> that code which changes behaviour depending on context should either be
> separated or the context be conveyed in an argument passed by the caller,
> which usually knows the context.
>
> Use the `sched_napi' argument passed by the callback. It is set true if
> called from the interrupt handler and NAPI should be scheduled.
>
> Signed-off-by: Sebastian Andrzej Siewior <[email protected]>
> Cc: "Horia Geantă" <[email protected]>
> Cc: Aymen Sghaier <[email protected]>
> Cc: Herbert Xu <[email protected]>
> Cc: "David S. Miller" <[email protected]>
> Cc: Madalin Bucur <[email protected]>
> Cc: Jakub Kicinski <[email protected]>
> Cc: Li Yang <[email protected]>
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
> Cc: [email protected]
Reviewed-by: Horia Geantă <[email protected]>

Thanks,
Horia