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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit X-Rspamd-Queue-Id: 93B6D160002 X-Rspam-User: X-Rspamd-Server: rspam07 X-Stat-Signature: rcyes96heybt7u98ck5q3exqsk8wg99j X-HE-Tag: 1745901638-71206 X-HE-Meta: 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 gF835RNA 8541d2PGJLTFI9T1YJQLqJZmLpuwI2Z19bgoOcBWoF68JOX+Typ5ylw0wYmqrqM1Zdp3J1LtbV1WIPySdncXHHTSe4BbyzNZyq6CMLHLGbTje+zJ2h82Nkj3MWgGj6Iwt74bWgkWoklo4ysL582VCEmnTpLYhDPFrAUTaElL8gUszKcw= X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: On 28/04/25 7:01 pm, Lance Yang wrote: > I'm hitting the following compilation errors after applying this patch > series: Not sure why is that. I cherry-picked my commits onto 6ebffe676fcf8d259e3fb5d5fbf1a8227f22182c and the kernel builds for me. Let me send a v2 rebased onto this. > > In file included from ./include/linux/kasan.h:37, >                  from ./include/linux/slab.h:260, >                  from ./include/linux/crypto.h:19, >                  from arch/x86/kernel/asm-offsets.c:9: > ./include/linux/pgtable.h: In function ‘modify_prot_start_ptes’: > ./include/linux/pgtable.h:905:15: error: implicit declaration of > function ‘ptep_modify_prot_start’ [-Werror=implicit-function-declaration] >   905 |         pte = ptep_modify_prot_start(vma, addr, ptep); >       |               ^~~~~~~~~~~~~~~~~~~~~~ > ./include/linux/pgtable.h:905:15: error: incompatible types when > assigning to type ‘pte_t’ from type ‘int’ > ./include/linux/pgtable.h:909:27: error: incompatible types when > assigning to type ‘pte_t’ from type ‘int’ >   909 |                 tmp_pte = ptep_modify_prot_start(vma, addr, ptep); >       |                           ^~~~~~~~~~~~~~~~~~~~~~ > ./include/linux/pgtable.h: In function ‘modify_prot_commit_ptes’: > ./include/linux/pgtable.h:925:17: error: implicit declaration of > function ‘ptep_modify_prot_commit’ [-Werror=implicit-function-declaration] >   925 |                 ptep_modify_prot_commit(vma, addr, ptep, > old_pte, pte); >       |                 ^~~~~~~~~~~~~~~~~~~~~~~ > ./include/linux/pgtable.h: At top level: > ./include/linux/pgtable.h:1360:21: error: conflicting types for > ‘ptep_modify_prot_start’; have ‘pte_t(struct vm_area_struct *, long > unsigned int,  pte_t *)’ >  1360 | static inline pte_t ptep_modify_prot_start(struct > vm_area_struct *vma, >       |                     ^~~~~~~~~~~~~~~~~~~~~~ > ./include/linux/pgtable.h:905:15: note: previous implicit declaration of > ‘ptep_modify_prot_start’ with type ‘int()’ >   905 |         pte = ptep_modify_prot_start(vma, addr, ptep); >       |               ^~~~~~~~~~~~~~~~~~~~~~ > ./include/linux/pgtable.h:1371:20: warning: conflicting types for > ‘ptep_modify_prot_commit’; have ‘void(struct vm_area_struct *, long > unsigned int,  pte_t *, pte_t,  pte_t)’ >  1371 | static inline void ptep_modify_prot_commit(struct > vm_area_struct *vma, >       |                    ^~~~~~~~~~~~~~~~~~~~~~~ > ./include/linux/pgtable.h:1371:20: error: static declaration of > ‘ptep_modify_prot_commit’ follows non-static declaration > ./include/linux/pgtable.h:925:17: note: previous implicit declaration of > ‘ptep_modify_prot_commit’ with type ‘void(struct vm_area_struct *, long > unsigned int,  pte_t *, pte_t,  pte_t)’ >   925 |                 ptep_modify_prot_commit(vma, addr, ptep, > old_pte, pte); >       |                 ^~~~~~~~~~~~~~~~~~~~~~~ > cc1: some warnings being treated as errors > make[2]: *** [scripts/Makefile.build:98: arch/x86/kernel/asm-offsets.s] > Error 1 > make[1]: *** [/home/runner/work/mm-test-robot/mm-test-robot/linux/ > Makefile:1280: prepare0] Error 2 > make: *** [Makefile:248: __sub-make] Error 2 > > Based on: > > mm-unstable b18dec6a6ad3d051dadc3c16fb838e4abddf8d3c ("mm/numa: remove > unnecessary local variable in alloc_node_data()") > > > Thanks, > Lance > > > > On 2025/4/28 20:04, Dev Jain wrote: >> This patchset optimizes the mprotect() system call for large folios >> by PTE-batching. >> >> We use the following test cases to measure performance, mprotect()'ing >> the mapped memory to read-only then read-write 40 times: >> >> Test case 1: Mapping 1G of memory, touching it to get PMD-THPs, then >> pte-mapping those THPs >> Test case 2: Mapping 1G of memory with 64K mTHPs >> Test case 3: Mapping 1G of memory with 4K pages >> >> Average execution time on arm64, Apple M3: >> Before the patchset: >> T1: 7.9 seconds   T2: 7.9 seconds   T3: 4.2 seconds >> >> After the patchset: >> T1: 2.1 seconds   T2: 2.2 seconds   T3: 4.2 seconds >> >> Observing T1/T2 and T3 before the patchset, we also remove the regression >> introduced by ptep_get() on a contpte block. And, for large folios we get >> an almost 276% performance improvement. >> >> Dev Jain (7): >>    mm: Refactor code in mprotect >>    mm: Optimize mprotect() by batch-skipping PTEs >>    mm: Add batched versions of ptep_modify_prot_start/commit >>    arm64: Add batched version of ptep_modify_prot_start >>    arm64: Add batched version of ptep_modify_prot_commit >>    mm: Batch around can_change_pte_writable() >>    mm: Optimize mprotect() through PTE-batching >> >>   arch/arm64/include/asm/pgtable.h |  10 ++ >>   arch/arm64/mm/mmu.c              |  21 +++- >>   include/linux/mm.h               |   4 +- >>   include/linux/pgtable.h          |  42 ++++++++ >>   mm/gup.c                         |   2 +- >>   mm/huge_memory.c                 |   4 +- >>   mm/memory.c                      |   6 +- >>   mm/mprotect.c                    | 163 +++++++++++++++++++++---------- >>   mm/pgtable-generic.c             |  16 ++- >>   9 files changed, 198 insertions(+), 70 deletions(-) >> > >