Messages in this thread | | | From | "Kirill A. Shutemov" <> | Subject | Re: [PATCH 34/34] mm: dynamically allocate page->ptl if it cannot be embedded to struct page | Date | Mon, 14 Oct 2013 12:04:37 +0300 (EEST) |
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Christoph Lameter wrote: > On Thu, 10 Oct 2013, Kirill A. Shutemov wrote: > > > Christoph Lameter wrote: > > > On Thu, 10 Oct 2013, Kirill A. Shutemov wrote: > > > > > > > +static inline bool ptlock_alloc(struct page *page) > > > > +{ > > > > + if (sizeof(spinlock_t) > sizeof(page->ptl)) > > > > + return __ptlock_alloc(page); > > > > + return true; > > > > +} > > > > > > Could you make the check a CONFIG option? CONFIG_PTLOCK_DOES_NOT_FIT_IN_PAGE_STRUCT or > > > so? > > > > No. We will have to track what affects sizeof(spinlock_t) manually. > > Not a fun and error prune. > > You can generate a config option depending on the size of the object via > Kbuild. Kbuild will determine the setting before building the kernel as a > whole by runing some small C program.
I don't think it's any better than what we have there now.
-- Kirill A. Shutemov
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