| Message ID | 20200422001422.232330-2-walken@google.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | Add a new mmap locking API wrapping mmap_sem calls | expand |
On 4/22/20 2:14 AM, Michel Lespinasse wrote: > This change wraps the existing mmap_sem related rwsem calls into a new > mmap locking API. There are two justifications for the new API: > > - At first, it provides an easy hooking point to instrument mmap_sem > locking latencies independently of any other rwsems. > > - In the future, it may be a starting point for replacing the rwsem > implementation with a different one, such as range locks. > > Signed-off-by: Michel Lespinasse <walken@google.com> > Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> > Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Le 22/04/2020 à 02:14, Michel Lespinasse a écrit : > This change wraps the existing mmap_sem related rwsem calls into a new > mmap locking API. There are two justifications for the new API: > > - At first, it provides an easy hooking point to instrument mmap_sem > locking latencies independently of any other rwsems. > > - In the future, it may be a starting point for replacing the rwsem > implementation with a different one, such as range locks. > > Signed-off-by: Michel Lespinasse <walken@google.com> > Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com> > Reviewed-by: Davidlohr Bueso <dbueso@suse.de> Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> > --- > include/linux/mm.h | 1 + > include/linux/mmap_lock.h | 54 +++++++++++++++++++++++++++++++++++++++ > 2 files changed, 55 insertions(+) > create mode 100644 include/linux/mmap_lock.h > > diff --git a/include/linux/mm.h b/include/linux/mm.h > index 5a323422d783..051ec782bdbb 100644 > --- a/include/linux/mm.h > +++ b/include/linux/mm.h > @@ -15,6 +15,7 @@ > #include <linux/atomic.h> > #include <linux/debug_locks.h> > #include <linux/mm_types.h> > +#include <linux/mmap_lock.h> > #include <linux/range.h> > #include <linux/pfn.h> > #include <linux/percpu-refcount.h> > diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h > new file mode 100644 > index 000000000000..97ac53b66052 > --- /dev/null > +++ b/include/linux/mmap_lock.h > @@ -0,0 +1,54 @@ > +#ifndef _LINUX_MMAP_LOCK_H > +#define _LINUX_MMAP_LOCK_H > + > +static inline void mmap_init_lock(struct mm_struct *mm) > +{ > + init_rwsem(&mm->mmap_sem); > +} > + > +static inline void mmap_write_lock(struct mm_struct *mm) > +{ > + down_write(&mm->mmap_sem); > +} > + > +static inline int mmap_write_lock_killable(struct mm_struct *mm) > +{ > + return down_write_killable(&mm->mmap_sem); > +} > + > +static inline bool mmap_write_trylock(struct mm_struct *mm) > +{ > + return down_write_trylock(&mm->mmap_sem) != 0; > +} > + > +static inline void mmap_write_unlock(struct mm_struct *mm) > +{ > + up_write(&mm->mmap_sem); > +} > + > +static inline void mmap_write_downgrade(struct mm_struct *mm) > +{ > + downgrade_write(&mm->mmap_sem); > +} > + > +static inline void mmap_read_lock(struct mm_struct *mm) > +{ > + down_read(&mm->mmap_sem); > +} > + > +static inline int mmap_read_lock_killable(struct mm_struct *mm) > +{ > + return down_read_killable(&mm->mmap_sem); > +} > + > +static inline bool mmap_read_trylock(struct mm_struct *mm) > +{ > + return down_read_trylock(&mm->mmap_sem) != 0; > +} > + > +static inline void mmap_read_unlock(struct mm_struct *mm) > +{ > + up_read(&mm->mmap_sem); > +} > + > +#endif /* _LINUX_MMAP_LOCK_H */ >
diff --git a/include/linux/mm.h b/include/linux/mm.h index 5a323422d783..051ec782bdbb 100644 --- a/include/linux/mm.h +++ b/include/linux/mm.h @@ -15,6 +15,7 @@ #include <linux/atomic.h> #include <linux/debug_locks.h> #include <linux/mm_types.h> +#include <linux/mmap_lock.h> #include <linux/range.h> #include <linux/pfn.h> #include <linux/percpu-refcount.h> diff --git a/include/linux/mmap_lock.h b/include/linux/mmap_lock.h new file mode 100644 index 000000000000..97ac53b66052 --- /dev/null +++ b/include/linux/mmap_lock.h @@ -0,0 +1,54 @@ +#ifndef _LINUX_MMAP_LOCK_H +#define _LINUX_MMAP_LOCK_H + +static inline void mmap_init_lock(struct mm_struct *mm) +{ + init_rwsem(&mm->mmap_sem); +} + +static inline void mmap_write_lock(struct mm_struct *mm) +{ + down_write(&mm->mmap_sem); +} + +static inline int mmap_write_lock_killable(struct mm_struct *mm) +{ + return down_write_killable(&mm->mmap_sem); +} + +static inline bool mmap_write_trylock(struct mm_struct *mm) +{ + return down_write_trylock(&mm->mmap_sem) != 0; +} + +static inline void mmap_write_unlock(struct mm_struct *mm) +{ + up_write(&mm->mmap_sem); +} + +static inline void mmap_write_downgrade(struct mm_struct *mm) +{ + downgrade_write(&mm->mmap_sem); +} + +static inline void mmap_read_lock(struct mm_struct *mm) +{ + down_read(&mm->mmap_sem); +} + +static inline int mmap_read_lock_killable(struct mm_struct *mm) +{ + return down_read_killable(&mm->mmap_sem); +} + +static inline bool mmap_read_trylock(struct mm_struct *mm) +{ + return down_read_trylock(&mm->mmap_sem) != 0; +} + +static inline void mmap_read_unlock(struct mm_struct *mm) +{ + up_read(&mm->mmap_sem); +} + +#endif /* _LINUX_MMAP_LOCK_H */