On Mon, Feb 23, 2026 at 02:36:01PM -0800, Shakeel Butt wrote:
> On Wed, Feb 11, 2026 at 03:22:13PM +0000, Dmitry Ilvokhin wrote:
> > Add thin wrappers around zone lock acquire/release operations. This
> > prepares the code for future tracepoint instrumentation without
> > modifying individual call sites.
> >
> > Centralizing zone lock operations behind wrappers allows future
> > instrumentation or debugging hooks to be added without touching
> > all users.
> >
> > No functional change intended. The wrappers are introduced in
> > preparation for subsequent patches and are not yet used.
> >
> > Signed-off-by: Dmitry Ilvokhin <[email protected]>
> > ---
> > MAINTAINERS | 1 +
> > include/linux/zone_lock.h | 38 ++++++++++++++++++++++++++++++++++++++
> > 2 files changed, 39 insertions(+)
> > create mode 100644 include/linux/zone_lock.h
> >
> > diff --git a/MAINTAINERS b/MAINTAINERS
> > index b4088f7290be..680c9ae02d7e 100644
> > --- a/MAINTAINERS
> > +++ b/MAINTAINERS
> > @@ -16498,6 +16498,7 @@ F: include/linux/pgtable.h
> > F: include/linux/ptdump.h
> > F: include/linux/vmpressure.h
> > F: include/linux/vmstat.h
> > +F: include/linux/zone_lock.h
> > F: kernel/fork.c
> > F: mm/Kconfig
> > F: mm/debug.c
> > diff --git a/include/linux/zone_lock.h b/include/linux/zone_lock.h
> > new file mode 100644
> > index 000000000000..c531e26280e6
> > --- /dev/null
> > +++ b/include/linux/zone_lock.h
> > @@ -0,0 +1,38 @@
> > +/* SPDX-License-Identifier: GPL-2.0 */
> > +#ifndef _LINUX_ZONE_LOCK_H
> > +#define _LINUX_ZONE_LOCK_H
> > +
> > +#include <linux/mmzone.h>
> > +#include <linux/spinlock.h>
> > +
> > +static inline void zone_lock_init(struct zone *zone)
> > +{
> > + spin_lock_init(&zone->lock);
> > +}
> > +
> > +#define zone_lock_irqsave(zone, flags) \
> > +do { \
> > + spin_lock_irqsave(&(zone)->lock, flags); \
> > +} while (0)
> > +
> > +#define zone_trylock_irqsave(zone, flags) \
> > +({ \
> > + spin_trylock_irqsave(&(zone)->lock, flags); \
> > +})
>
> Any reason you used macros for above two and inlined functions for remaining?
>
The reason for using macros in those two cases is that they need to
modify the flags variable passed by the caller, just like
spin_lock_irqsave() and spin_trylock_irqsave() do. I followed the same
convention here.
If we used normal inline functions instead, we would need to pass a
pointer to flags, which would change the call sites and diverge from the
existing *_irqsave() locking pattern.
There is also a difference between zone_lock_irqsave() and
zone_trylock_irqsave() implementations: the former is implemented as a
do { } while (0) macro since it does not return a value, while the
latter uses a GCC extension in order to return the trylock result. This
matches spin_lock_* convention as well.
> > +
> > +static inline void zone_unlock_irqrestore(struct zone *zone, unsigned long
> > flags)
> > +{
> > + spin_unlock_irqrestore(&zone->lock, flags);
> > +}
> > +
> > +static inline void zone_lock_irq(struct zone *zone)
> > +{
> > + spin_lock_irq(&zone->lock);
> > +}
> > +
> > +static inline void zone_unlock_irq(struct zone *zone)
> > +{
> > + spin_unlock_irq(&zone->lock);
> > +}
> > +
> > +#endif /* _LINUX_ZONE_LOCK_H */
> > --
> > 2.47.3
> >
