Re: [v2 PATCH] mm: gup: do not call try_grab_folio() in slow path

On Thu, Jun 27, 2024 at 11:35 PM Christoph Hellwig hch@infradead.org wrote:

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+int __must_check try_grab_folio(struct folio *folio, int refs, unsigned int flags)

Overly long line (same for the external declaration)

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• struct page *page = &folio->page;
  

Page is only used for is_pci_p2pdma_page and is_zero_page, and for the latter a is_zero_folio already exist. Maybe remove the local variable, use is_zero_folio and just open code the dereference in the is_pci_p2pdma_page call?

Thanks, Christoph. Good point, I think we can use is_zero_folio and open coeded it in is_pci_p2pdma_page.

And all the format problems will be solved in v3.

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•         ret = gup_hugepte(vma, ptep, sz, addr, end, flags, pages, nr, fast);
  

Overly lone line.

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•         folio_ref_add(folio,
  

•                         refs * (GUP_PIN_COUNTING_BIAS - 1));
  

Nit: this easily fits onto a single line.

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                  if (gup_hugepd(NULL, __hugepd(pmd_val(pmd)), addr,

•                                PMD_SHIFT, next, flags, pages, nr) != 1)
  

•                                PMD_SHIFT, next, flags, pages, nr, true) != 1)
  

Overly long lin (same in the similar calls below)