| Message ID | 20141016092529.GA1524@linaro.org |
|---|---|
| State | New |
| Headers | show |
Steve Capper <steve.capper@linaro.org> writes: > On Wed, Oct 15, 2014 at 10:04:47PM +0530, Aneesh Kumar K.V wrote: >> Update generic gup implementation with powerpc specific details. >> On powerpc at pmd level we can have hugepte, normal pmd pointer >> or a pointer to the hugepage directory. >> >> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> > > Hi, > This patch causes compiler errors on arm and arm64 due to pgd_huge > being undefined. I've attached a fixup below, this fixup will require > that #define pgd_huge(pgd) 0 be added back into: > arch/powerpc/include/asm/page.h > For the second patch in this series. > > Another avenue would be to do something like: > #ifndef pgd_huge > #define pgd_huge(pgd) (0) > #endif > > Then no changes would be required to arm and arm64 (or other > architectures). > > To help with bisectability, could we please have a suitable fix applied > to the two patches in the -mm tree: > http://ozlabs.org/~akpm/mmots/broken-out/mm-update-generic-gup-implementation-to-handle-hugepage-directory.patch > http://ozlabs.org/~akpm/mmots/broken-out/arch-powerpc-switch-to-generic-rcu-get_user_pages_fast.patch > > rather than applied afterwards? > > With pgd_huge(x) defined, this patch passes my futex test on arm > (Arndale platform) and arm64(Juno). > > Cheers, > -- > Steve > > > > From 2fb7b0308f0aca94c50611257ba82d656abb0768 Mon Sep 17 00:00:00 2001 > From: Steve Capper <steve.capper@linaro.org> > Date: Thu, 16 Oct 2014 09:09:48 +0100 > Subject: [PATCH] Fixup for Update generic gup implementation > > The patch: > mm: Update generic gup implementation to handle hugepage directory > > will not compile for arm or arm64 due to pgd_huge being undefined. > > Signed-off-by: Steve Capper <steve.capper@linaro.org> > --- > arch/arm/include/asm/pgtable.h | 2 ++ > arch/arm64/include/asm/pgtable.h | 2 ++ > include/linux/hugetlb.h | 1 - > 3 files changed, 4 insertions(+), 1 deletion(-) > > diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h > index 90aa4583..46f81fb 100644 > --- a/arch/arm/include/asm/pgtable.h > +++ b/arch/arm/include/asm/pgtable.h > @@ -181,6 +181,8 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; > /* to find an entry in a kernel page-table-directory */ > #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) > > +#define pgd_huge(pgd) (0) > + > #define pmd_none(pmd) (!pmd_val(pmd)) > #define pmd_present(pmd) (pmd_val(pmd)) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index 464c5ce..d4462ca 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -462,6 +462,8 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) > extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; > extern pgd_t idmap_pg_dir[PTRS_PER_PGD]; > > +#define pgd_huge(pgd) (0) > + > /* > * Encode and decode a swap entry: > * bits 0-1: present (must be zero) > diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h > index 65e12a2..6e6d338 100644 > --- a/include/linux/hugetlb.h > +++ b/include/linux/hugetlb.h > @@ -138,7 +138,6 @@ static inline void hugetlb_show_meminfo(void) > #define prepare_hugepage_range(file, addr, len) (-EINVAL) > #define pmd_huge(x) 0 > #define pud_huge(x) 0 > -#define pgd_huge(x) 0 > #define is_hugepage_only_range(mm, addr, len) 0 > #define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; }) > #define hugetlb_fault(mm, vma, addr, flags) ({ BUG(); 0; }) don't do the last hunk, that will result in build failures on sub platforms on ppc64. can you do the arm patch without making the change to hugetlb.h ? -aneesh -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/
On Thu, Oct 16, 2014 at 08:48:20PM +0530, Aneesh Kumar K.V wrote: > Steve Capper <steve.capper@linaro.org> writes: > > > On Wed, Oct 15, 2014 at 10:04:47PM +0530, Aneesh Kumar K.V wrote: > >> Update generic gup implementation with powerpc specific details. > >> On powerpc at pmd level we can have hugepte, normal pmd pointer > >> or a pointer to the hugepage directory. > >> > >> Signed-off-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com> > > > > Hi, > > This patch causes compiler errors on arm and arm64 due to pgd_huge > > being undefined. I've attached a fixup below, this fixup will require > > that #define pgd_huge(pgd) 0 be added back into: > > arch/powerpc/include/asm/page.h > > For the second patch in this series. > > > > Another avenue would be to do something like: > > #ifndef pgd_huge > > #define pgd_huge(pgd) (0) > > #endif > > > > Then no changes would be required to arm and arm64 (or other > > architectures). > > > > To help with bisectability, could we please have a suitable fix applied > > to the two patches in the -mm tree: > > http://ozlabs.org/~akpm/mmots/broken-out/mm-update-generic-gup-implementation-to-handle-hugepage-directory.patch > > http://ozlabs.org/~akpm/mmots/broken-out/arch-powerpc-switch-to-generic-rcu-get_user_pages_fast.patch > > > > rather than applied afterwards? > > > > With pgd_huge(x) defined, this patch passes my futex test on arm > > (Arndale platform) and arm64(Juno). > > > > Cheers, > > -- > > Steve > > > > > > > > From 2fb7b0308f0aca94c50611257ba82d656abb0768 Mon Sep 17 00:00:00 2001 > > From: Steve Capper <steve.capper@linaro.org> > > Date: Thu, 16 Oct 2014 09:09:48 +0100 > > Subject: [PATCH] Fixup for Update generic gup implementation > > > > The patch: > > mm: Update generic gup implementation to handle hugepage directory > > > > will not compile for arm or arm64 due to pgd_huge being undefined. > > > > Signed-off-by: Steve Capper <steve.capper@linaro.org> > > --- > > arch/arm/include/asm/pgtable.h | 2 ++ > > arch/arm64/include/asm/pgtable.h | 2 ++ > > include/linux/hugetlb.h | 1 - > > 3 files changed, 4 insertions(+), 1 deletion(-) > > > > diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h > > index 90aa4583..46f81fb 100644 > > --- a/arch/arm/include/asm/pgtable.h > > +++ b/arch/arm/include/asm/pgtable.h > > @@ -181,6 +181,8 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; > > /* to find an entry in a kernel page-table-directory */ > > #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) > > > > +#define pgd_huge(pgd) (0) > > + > > #define pmd_none(pmd) (!pmd_val(pmd)) > > #define pmd_present(pmd) (pmd_val(pmd)) > > > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > > index 464c5ce..d4462ca 100644 > > --- a/arch/arm64/include/asm/pgtable.h > > +++ b/arch/arm64/include/asm/pgtable.h > > @@ -462,6 +462,8 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) > > extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; > > extern pgd_t idmap_pg_dir[PTRS_PER_PGD]; > > > > +#define pgd_huge(pgd) (0) > > + > > /* > > * Encode and decode a swap entry: > > * bits 0-1: present (must be zero) > > diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h > > index 65e12a2..6e6d338 100644 > > --- a/include/linux/hugetlb.h > > +++ b/include/linux/hugetlb.h > > @@ -138,7 +138,6 @@ static inline void hugetlb_show_meminfo(void) > > #define prepare_hugepage_range(file, addr, len) (-EINVAL) > > #define pmd_huge(x) 0 > > #define pud_huge(x) 0 > > -#define pgd_huge(x) 0 > > #define is_hugepage_only_range(mm, addr, len) 0 > > #define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; }) > > #define hugetlb_fault(mm, vma, addr, flags) ({ BUG(); 0; }) > > don't do the last hunk, that will result in build failures on sub > platforms on ppc64. can you do the arm patch without making the change > to hugetlb.h ? > Hi Aneesh, The problem with leaving the empty pgd_huge in hugetlb.h is that we would then have to resort to patterns like this for both arm and arm64: #ifdef CONFIG_HUGETLB_PAGE #define pgd_huge(pgd) (0) #endif If possible, I'd much rather just have: #define pgd_huge(pgd) (0) After the second patch in this series we already have the following code pattern in arch/powerpc/include/asm/page.h: #define is_hugepd(hpd) (hugepd_ok(hpd)) int pgd_huge(pgd_t pgd); #else /* CONFIG_HUGETLB_PAGE */ #define is_hugepd(pdep) 0 #endif /* CONFIG_HUGETLB_PAGE */ #define __hugepd(x) ((hugepd_t) { (x) }) Can we not just add a: #define pgd_huge(pgd) (0) above the "#endif /* CONFIG_HUGETLB_PAGE */" line in the second patch? (or, more precisely, prevent the second patch from removing this line). That way we get a clearer code overall? Cheers,
diff --git a/arch/arm/include/asm/pgtable.h b/arch/arm/include/asm/pgtable.h index 90aa4583..46f81fb 100644 --- a/arch/arm/include/asm/pgtable.h +++ b/arch/arm/include/asm/pgtable.h @@ -181,6 +181,8 @@ extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; /* to find an entry in a kernel page-table-directory */ #define pgd_offset_k(addr) pgd_offset(&init_mm, addr) +#define pgd_huge(pgd) (0) + #define pmd_none(pmd) (!pmd_val(pmd)) #define pmd_present(pmd) (pmd_val(pmd)) diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index 464c5ce..d4462ca 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -462,6 +462,8 @@ static inline pmd_t pmd_modify(pmd_t pmd, pgprot_t newprot) extern pgd_t swapper_pg_dir[PTRS_PER_PGD]; extern pgd_t idmap_pg_dir[PTRS_PER_PGD]; +#define pgd_huge(pgd) (0) + /* * Encode and decode a swap entry: * bits 0-1: present (must be zero) diff --git a/include/linux/hugetlb.h b/include/linux/hugetlb.h index 65e12a2..6e6d338 100644 --- a/include/linux/hugetlb.h +++ b/include/linux/hugetlb.h @@ -138,7 +138,6 @@ static inline void hugetlb_show_meminfo(void) #define prepare_hugepage_range(file, addr, len) (-EINVAL) #define pmd_huge(x) 0 #define pud_huge(x) 0 -#define pgd_huge(x) 0 #define is_hugepage_only_range(mm, addr, len) 0 #define hugetlb_free_pgd_range(tlb, addr, end, floor, ceiling) ({BUG(); 0; }) #define hugetlb_fault(mm, vma, addr, flags) ({ BUG(); 0; })