Messages in this thread | | | Date | Tue, 28 Jun 2022 16:31:02 +0100 | From | Vincenzo Frascino <> | Subject | Re: [PATCH v2 net-next 4/4] time64.h: consolidate uses of PSEC_PER_NSEC |
| |
On 6/28/22 15:52, Vladimir Oltean wrote: > Time-sensitive networking code needs to work with PTP times expressed in > nanoseconds, and with packet transmission times expressed in > picoseconds, since those would be fractional at higher than gigabit > speed when expressed in nanoseconds. > > Convert the existing uses in tc-taprio and the ocelot/felix DSA driver > to a PSEC_PER_NSEC macro. This macro is placed in include/linux/time64.h > as opposed to its relatives (PSEC_PER_SEC etc) from include/vdso/time64.h > because the vDSO library does not (yet) need/use it. > > Cc: Andy Lutomirski <luto@kernel.org> > Cc: Thomas Gleixner <tglx@linutronix.de> > Cc: Vincenzo Frascino <vincenzo.frascino@arm.com> > Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vincenzo Frascino <vincenzo.frascino@arm.com> # for the vDSO parts
> --- > v1->v2: > - move PSEC_PER_NSEC to include/linux/time64.h > - add missing include of linux/time.h > > drivers/net/dsa/ocelot/felix_vsc9959.c | 5 +++-- > include/linux/time64.h | 3 +++ > net/sched/sch_taprio.c | 5 +++-- > 3 files changed, 9 insertions(+), 4 deletions(-) > > diff --git a/drivers/net/dsa/ocelot/felix_vsc9959.c b/drivers/net/dsa/ocelot/felix_vsc9959.c > index 27d8b56cc21c..28bd4892c30a 100644 > --- a/drivers/net/dsa/ocelot/felix_vsc9959.c > +++ b/drivers/net/dsa/ocelot/felix_vsc9959.c > @@ -16,6 +16,7 @@ > #include <linux/iopoll.h> > #include <linux/mdio.h> > #include <linux/pci.h> > +#include <linux/time.h> > #include "felix.h" > > #define VSC9959_NUM_PORTS 6 > @@ -1235,7 +1236,7 @@ static void vsc9959_tas_guard_bands_update(struct ocelot *ocelot, int port) > u32 max_sdu; > > if (min_gate_len[tc] == U64_MAX /* Gate always open */ || > - min_gate_len[tc] * 1000 > needed_bit_time_ps) { > + min_gate_len[tc] * PSEC_PER_NSEC > needed_bit_time_ps) { > /* Setting QMAXSDU_CFG to 0 disables oversized frame > * dropping. > */ > @@ -1249,7 +1250,7 @@ static void vsc9959_tas_guard_bands_update(struct ocelot *ocelot, int port) > * frame, make sure to enable oversize frame dropping > * for frames larger than the smallest that would fit. > */ > - max_sdu = div_u64(min_gate_len[tc] * 1000, > + max_sdu = div_u64(min_gate_len[tc] * PSEC_PER_NSEC, > picos_per_byte); > /* A TC gate may be completely closed, which is a > * special case where all packets are oversized. > diff --git a/include/linux/time64.h b/include/linux/time64.h > index 81b9686a2079..2fb8232cff1d 100644 > --- a/include/linux/time64.h > +++ b/include/linux/time64.h > @@ -20,6 +20,9 @@ struct itimerspec64 { > struct timespec64 it_value; > }; > > +/* Parameters used to convert the timespec values: */ > +#define PSEC_PER_NSEC 1000L > + > /* Located here for timespec[64]_valid_strict */ > #define TIME64_MAX ((s64)~((u64)1 << 63)) > #define TIME64_MIN (-TIME64_MAX - 1) > diff --git a/net/sched/sch_taprio.c b/net/sched/sch_taprio.c > index b9c71a304d39..0b941dd63d26 100644 > --- a/net/sched/sch_taprio.c > +++ b/net/sched/sch_taprio.c > @@ -18,6 +18,7 @@ > #include <linux/module.h> > #include <linux/spinlock.h> > #include <linux/rcupdate.h> > +#include <linux/time.h> > #include <net/netlink.h> > #include <net/pkt_sched.h> > #include <net/pkt_cls.h> > @@ -176,7 +177,7 @@ static ktime_t get_interval_end_time(struct sched_gate_list *sched, > > static int length_to_duration(struct taprio_sched *q, int len) > { > - return div_u64(len * atomic64_read(&q->picos_per_byte), 1000); > + return div_u64(len * atomic64_read(&q->picos_per_byte), PSEC_PER_NSEC); > } > > /* Returns the entry corresponding to next available interval. If > @@ -551,7 +552,7 @@ static struct sk_buff *taprio_peek(struct Qdisc *sch) > static void taprio_set_budget(struct taprio_sched *q, struct sched_entry *entry) > { > atomic_set(&entry->budget, > - div64_u64((u64)entry->interval * 1000, > + div64_u64((u64)entry->interval * PSEC_PER_NSEC, > atomic64_read(&q->picos_per_byte))); > } >
-- Regards, Vincenzo
| |