Messages in this thread | | | Date | Wed, 06 Apr 2005 13:09:41 -0400 | From | Brian Gerst <> | Subject | Re: return value of ptep_get_and_clear |
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Kumar Gala wrote: > ptep_get_and_clear has a signature that looks something like: > > static inline pte_t ptep_get_and_clear(struct mm_struct *mm, unsigned > long addr, > pte_t *ptep) > > It appears that its suppose to return the pte_t pointed to by ptep > before its modified. Why do we bother doing this? The caller seems > perfectly able to dereference ptep and hold on to it. Am I missing > something here? > > If not, I'll work up a set of patches to change ptep_get_and_clear and > its callers for post 2.6.12 release. > > - kumar
Because it is an atomic operation. If you dereference it before ptep_get_and_clear() it could change in between.
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