| Message ID | 20190427012842.93737-1-cai@lca.pw (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | arm64: fix pte_unmap() -Wunused-but-set-variable | expand |
On Fri, Apr 26, 2019 at 09:28:42PM -0400, Qian Cai wrote: > Many compilation warnings due to pte_unmap() compiles away. Fixed it by > making it an static inline function. > > mm/gup.c: In function 'gup_pte_range': > mm/gup.c:1727:16: warning: variable 'ptem' set but not used > [-Wunused-but-set-variable] > mm/gup.c: At top level: > mm/memory.c: In function 'copy_pte_range': > mm/memory.c:821:24: warning: variable 'orig_dst_pte' set but not used > [-Wunused-but-set-variable] > mm/memory.c:821:9: warning: variable 'orig_src_pte' set but not used > [-Wunused-but-set-variable] > mm/swap_state.c: In function 'swap_ra_info': > mm/swap_state.c:641:15: warning: variable 'orig_pte' set but not used > [-Wunused-but-set-variable] > mm/madvise.c: In function 'madvise_free_pte_range': > mm/madvise.c:318:9: warning: variable 'orig_pte' set but not used > [-Wunused-but-set-variable] > > Also, remove pte_unmap_nested() as nobody uses it anymore since the > commit ece0e2b6406a ("mm: remove pte_*map_nested()"). Can you post that as a separate patch which also removes pte_offset_map_nested(), please? > Signed-off-by: Qian Cai <cai@lca.pw> > --- > arch/arm64/include/asm/pgtable.h | 4 ++-- > 1 file changed, 2 insertions(+), 2 deletions(-) > > diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h > index de70c1eabf33..7543e345e078 100644 > --- a/arch/arm64/include/asm/pgtable.h > +++ b/arch/arm64/include/asm/pgtable.h > @@ -478,6 +478,8 @@ static inline phys_addr_t pmd_page_paddr(pmd_t pmd) > return __pmd_to_phys(pmd); > } > > +static inline void pte_unmap(pte_t *pte) { } Hmm, is this guaranteed to stop the compiler from warning? Assuming the pte_unmap() call is inlined, I'd expect it to keep complaining. What compiler are you using? Also, there are a bunch of other architectures that I would expect to have this same issue because they defined pte_unmap() exactly the same way. Will
On Mon, 2019-04-29 at 17:49 +0100, Will Deacon wrote: > > arch/arm64/include/asm/pgtable.h | 4 ++-- > > 1 file changed, 2 insertions(+), 2 deletions(-) > > > > diff --git a/arch/arm64/include/asm/pgtable.h > > b/arch/arm64/include/asm/pgtable.h > > index de70c1eabf33..7543e345e078 100644 > > --- a/arch/arm64/include/asm/pgtable.h > > +++ b/arch/arm64/include/asm/pgtable.h > > @@ -478,6 +478,8 @@ static inline phys_addr_t pmd_page_paddr(pmd_t pmd) > > return __pmd_to_phys(pmd); > > } > > > > +static inline void pte_unmap(pte_t *pte) { } > > Hmm, is this guaranteed to stop the compiler from warning? Assuming the > pte_unmap() call is inlined, I'd expect it to keep complaining. What > compiler are you using? Yes, it is guaranteed. Tested on both gcc and clang. > > Also, there are a bunch of other architectures that I would expect to have > this same issue because they defined pte_unmap() exactly the same way. This has already fixed in powerpc that went in. https://lore.kernel.org/lkml/20190307144031.52494-1-cai@lca.pw/ I am not sure if I care about any other arches nor I have real hardware to test further.
diff --git a/arch/arm64/include/asm/pgtable.h b/arch/arm64/include/asm/pgtable.h index de70c1eabf33..7543e345e078 100644 --- a/arch/arm64/include/asm/pgtable.h +++ b/arch/arm64/include/asm/pgtable.h @@ -478,6 +478,8 @@ static inline phys_addr_t pmd_page_paddr(pmd_t pmd) return __pmd_to_phys(pmd); } +static inline void pte_unmap(pte_t *pte) { } + /* Find an entry in the third-level page table. */ #define pte_index(addr) (((addr) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1)) @@ -486,8 +488,6 @@ static inline phys_addr_t pmd_page_paddr(pmd_t pmd) #define pte_offset_map(dir,addr) pte_offset_kernel((dir), (addr)) #define pte_offset_map_nested(dir,addr) pte_offset_kernel((dir), (addr)) -#define pte_unmap(pte) do { } while (0) -#define pte_unmap_nested(pte) do { } while (0) #define pte_set_fixmap(addr) ((pte_t *)set_fixmap_offset(FIX_PTE, addr)) #define pte_set_fixmap_offset(pmd, addr) pte_set_fixmap(pte_offset_phys(pmd, addr))
Many compilation warnings due to pte_unmap() compiles away. Fixed it by making it an static inline function. mm/gup.c: In function 'gup_pte_range': mm/gup.c:1727:16: warning: variable 'ptem' set but not used [-Wunused-but-set-variable] mm/gup.c: At top level: mm/memory.c: In function 'copy_pte_range': mm/memory.c:821:24: warning: variable 'orig_dst_pte' set but not used [-Wunused-but-set-variable] mm/memory.c:821:9: warning: variable 'orig_src_pte' set but not used [-Wunused-but-set-variable] mm/swap_state.c: In function 'swap_ra_info': mm/swap_state.c:641:15: warning: variable 'orig_pte' set but not used [-Wunused-but-set-variable] mm/madvise.c: In function 'madvise_free_pte_range': mm/madvise.c:318:9: warning: variable 'orig_pte' set but not used [-Wunused-but-set-variable] Also, remove pte_unmap_nested() as nobody uses it anymore since the commit ece0e2b6406a ("mm: remove pte_*map_nested()"). Signed-off-by: Qian Cai <cai@lca.pw> --- arch/arm64/include/asm/pgtable.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)