Messages in this thread | | | Date | Thu, 15 Jan 2015 21:30:12 -0600 (CST) | From | Christoph Lameter <> | Subject | Re: [PATCH v2 2/2] mm: don't use compound_head() in virt_to_head_page() |
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On Thu, 15 Jan 2015, Andrew Morton wrote:
> And perhaps some explanation here as to why virt_to_head_page() can > safely use compound_head_fast(). There's an assumption here that > nobody will be dismantling the compound page while virt_to_head_page() > is in progress, yes? And this assumption also holds for the calling > code, because otherwise the virt_to_head_page() return value is kinda > meaningless.
I think this assumption is pretty natural to make. A coupound_head that works well while dismantling a compound page should be marked specially and Joonsoo's definition should be the standard.
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