svn commit: r366265 - head/sys/sys

[Warner Losh]

On Tue, Sep 29, 2020, 1:00 PM Hans Petter Selasky <hps at selasky.org> wrote:

> On 2020-09-29 20:06, Warner Losh wrote:
> > Author: imp
> > Date: Tue Sep 29 18:06:02 2020
> > New Revision: 366265
> > URL: https://svnweb.freebsd.org/changeset/base/366265
> >
> > Log:
> >    Standalone SX shims
> >
> >    Create a do-nothing version of SX locks. OpenZFS needs them. However,
> >    since the boot loader is single threaded, they can be nops.
> >
> > Modified:
> >    head/sys/sys/sx.h
> >
> > Modified: head/sys/sys/sx.h
> >
> ==============================================================================
> > --- head/sys/sys/sx.h Tue Sep 29 17:52:15 2020        (r366264)
> > +++ head/sys/sys/sx.h Tue Sep 29 18:06:02 2020        (r366265)
> > @@ -300,4 +300,26 @@ __sx_xunlock(struct sx *sx, struct thread *td,
> const c
> >
> >   #endif /* _KERNEL */
> >
> > +#ifdef _STANDALONE
> > +/* since we have no threads in the boot loader, trivially implement
> no-op version */
> > +#define sx_xlock(s) (1)
> > +#define sx_try_xlock(s) (1)
> > +#define sx_xunlock(s) (1)
> > +#define SX_DUPOK 0
> > +#define SX_NEW 0
> > +#define SX_NOWITNESS 0
> > +
> > +static __inline void
> > +sx_init_flags(struct sx *sx, const char *description, int opts)
> > +{
> > +
> > +}
> > +
> > +static __inline void
> > +sx_destroy(struct sx *sx)
> > +{
> > +
> > +}
> > +#endif /* _STANDALONE */
> > +
> >   #endif /* !_SYS_SX_H_ */
> >
>
> You may want to use:
>
> bsd_kernel.c:sx_init_flags(struct sx *sx, const char *name, int flags)
> bsd_kernel.c:   sx->owned = 0;
> bsd_kernel.c:sx_destroy(struct sx *sx)
> bsd_kernel.c:sx_xlock(struct sx *sx)
> bsd_kernel.c:   sx->owned++;
> bsd_kernel.c:sx_xunlock(struct sx *sx)
> bsd_kernel.c:   sx->owned--;
> bsd_kernel.c:sx_xlocked(struct sx *sx)
> bsd_kernel.c:   return (sx->owned != 0);
> bsd_kernel.h:struct sx {
> bsd_kernel.h:#define    sx_assert(...) do { } while (0)
> bsd_kernel.h:#define    sx_init(...) sx_init_flags(__VA_ARGS__, 0)
> bsd_kernel.h:void       sx_init_flags(struct sx *, const char *, int);
> bsd_kernel.h:void       sx_destroy(struct sx *);
> bsd_kernel.h:void       sx_xlock(struct sx *);
> bsd_kernel.h:void       sx_xunlock(struct sx *);
> bsd_kernel.h:int        sx_xlocked(struct sx *);
>
> from "src/stand/kshim"
>

Yea. This, and other parts of the shims, need to be integrated into stand...

Warner

>