Messages in this thread | | | Date | Tue, 20 Feb 2018 15:02:52 +0100 | From | Daniel Vetter <> | Subject | Re: [PATCH 1/4] locking/ww_mutex: add ww_mutex_is_owned_by function v3 |
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On Tue, Feb 20, 2018 at 01:58:26PM +0100, Christian König wrote: > amdgpu needs to verify if userspace sends us valid addresses and the simplest > way of doing this is to check if the buffer object is locked with the ticket > of the current submission. > > Clean up the access to the ww_mutex internals by providing a function > for this and extend the check to the thread owning the underlying mutex. > > v2: split amdgpu changes into separate patch as suggested by Alex > v3: change logic as suggested by Daniel > > Signed-off-by: Christian König <christian.koenig@amd.com> > --- > include/linux/ww_mutex.h | 17 +++++++++++++++++ > 1 file changed, 17 insertions(+) > > diff --git a/include/linux/ww_mutex.h b/include/linux/ww_mutex.h > index 39fda195bf78..14e4149d3d9d 100644 > --- a/include/linux/ww_mutex.h > +++ b/include/linux/ww_mutex.h > @@ -358,4 +358,21 @@ static inline bool ww_mutex_is_locked(struct ww_mutex *lock) > return mutex_is_locked(&lock->base); > } > > +/** > + * ww_mutex_is_owned_by - is the w/w mutex locked by this task in that context > + * @lock: the mutex to be queried > + * @ctx: the w/w acquire context to test > + * > + * If @ctx is not NULL test if the mutex is owned by this context. > + * If @ctx is NULL test if the mutex is owned by the current thread.
This is a bit much how and not so much why, but I couldn't come up with a concise text what was materially better.
Reviewed-by: Daniel Vetter <daniel.vetter@ffwll.ch>
> + */ > +static inline bool ww_mutex_is_owned_by(struct ww_mutex *lock, > + struct ww_acquire_ctx *ctx) > +{ > + if (ctx) > + return likely(READ_ONCE(lock->ctx) == ctx); > + else > + return likely(__mutex_owner(&lock->base) == current); > +} > + > #endif > -- > 2.14.1 > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel
-- Daniel Vetter Software Engineer, Intel Corporation http://blog.ffwll.ch
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