On Sun, 8 May 2022 21:40:58 +0200
Mattias Rönnblom <hof...@lysator.liu.se> wrote:
> > I think would be good to have the sequence count (read side only) like
> > the kernel and sequence lock (sequence count + spinlock) as separate things.
> >
> > That way the application could use sequence count + ticket lock if it
> > needed to scale to more writers.
> >
>
> Sounds reasonable. Would that be something like:
>
> typedef struct {
> uint32_t sn;
> } rte_seqlock_t;
>
> rte_seqlock_read_begin()
> rte_seqlock_read_retry()
> rte_seqlock_write_begin()
> rte_seqlock_write_end()
>
> typedef struct {
> rte_seqlock_t seqlock;
> rte_spinlock_t wlock;
> } rte_<something>_t;
>
> rte_<something>_read_begin()
> rte_<something>_read_retry()
> rte_<something>_write_lock()
> rte_<something>_write_unlock()
>
> or are you suggesting removing the spinlock altogether, and leave
> writer-side synchronization to the application (at least in this DPDK
> release)?
No, like Linux kernel. Use seqcount for the reader counter only object
and seqlock for the seqcount + spinlock version.
