Message ID | 20170714015258.7933-3-benh@kernel.crashing.org (mailing list archive) |
---|---|
State | Superseded |
Headers | show |
Benjamin Herrenschmidt <benh@kernel.crashing.org> writes: > We do that because it's used by THP pmd collapsing, so use > instead a dedicated flush function. > > Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> > --- > .../powerpc/include/asm/book3s/64/tlbflush-radix.h | 1 + > arch/powerpc/mm/pgtable-radix.c | 5 ++- > arch/powerpc/mm/tlb-radix.c | 41 +++++++++++++++++++--- > 3 files changed, 41 insertions(+), 6 deletions(-) > > diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h b/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h > index 7196999..9b433a6 100644 > --- a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h > +++ b/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h > @@ -36,6 +36,7 @@ extern void radix__flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmad > #define radix__flush_tlb_page_psize(mm,addr,p) radix__local_flush_tlb_page_psize(mm,addr,p) > #endif > extern void radix__flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr); > +extern void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr); > extern void radix__flush_tlb_lpid_va(unsigned long lpid, unsigned long gpa, > unsigned long page_size); > extern void radix__flush_tlb_lpid(unsigned long lpid); > diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c > index c28165d..83d70f7 100644 > --- a/arch/powerpc/mm/pgtable-radix.c > +++ b/arch/powerpc/mm/pgtable-radix.c > @@ -706,9 +706,12 @@ pmd_t radix__pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long addre > */ > pmd = *pmdp; > pmd_clear(pmdp); > + > /*FIXME!! Verify whether we need this kick below */ > kick_all_cpus_sync(); > - flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); > + > + radix__flush_tlb_collapsed_pmd(vma->vm_mm, address); > + > return pmd; > } > > diff --git a/arch/powerpc/mm/tlb-radix.c b/arch/powerpc/mm/tlb-radix.c > index f65c928..73d3fbf 100644 > --- a/arch/powerpc/mm/tlb-radix.c > +++ b/arch/powerpc/mm/tlb-radix.c > @@ -267,11 +267,7 @@ void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start, > { > struct mm_struct *mm = vma->vm_mm; > > - /* > - * This is currently used when collapsing THPs so we need to > - * flush the PWC. We should fix this. > - */ > - radix__flush_all_mm(mm); > + radix__flush_tlb_mm(mm); > } > EXPORT_SYMBOL(radix__flush_tlb_range); > > @@ -350,6 +346,41 @@ void radix__flush_tlb_range_psize(struct mm_struct *mm, unsigned long start, > preempt_enable(); > } > > +void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr) > +{ > + int local = mm_is_thread_local(mm); > + unsigned long ap = mmu_get_ap(mmu_virtual_psize); > + unsigned long pid, end; > + > + > + pid = mm ? mm->context.id : 0; > + if (unlikely(pid == MMU_NO_CONTEXT)) > + goto no_context; > + > + /* 4k page size, just blow the world */ > + if (PAGE_SIZE == 0x1000) { > + radix__flush_all_mm(mm); > + return; > + } What is special here ? because it is 4096 tlb flushes ? > + > + /* Otherwise first do the PWC */ > + if (local) > + _tlbiel_pid(pid, RIC_FLUSH_PWC); > + else > + _tlbie_pid(pid, RIC_FLUSH_PWC); > + > + /* Then iterate the pages */ > + end = addr + HPAGE_PMD_SIZE; > + for (; addr < end; addr += PAGE_SIZE) { > + if (local) > + _tlbiel_va(addr, pid, ap, RIC_FLUSH_TLB); > + else > + _tlbie_va(addr, pid, ap, RIC_FLUSH_TLB); > + } > +no_context: > + preempt_enable(); > +} > + > void radix__flush_tlb_lpid_va(unsigned long lpid, unsigned long gpa, > unsigned long page_size) > { > -- > 2.9.4
On Fri, 2017-07-14 at 11:14 +0530, Aneesh Kumar K.V wrote: > > + pid = mm ? mm->context.id : 0; > > + if (unlikely(pid == MMU_NO_CONTEXT)) > > + goto no_context; > > + > > + /* 4k page size, just blow the world */ > > + if (PAGE_SIZE == 0x1000) { > > + radix__flush_all_mm(mm); > > + return; > > + } > > What is special here ? because it is 4096 tlb flushes ? Yes, keeping in line with the existing logic in flush_tlb_pages(), more than 32, do a full flush. Cheers, Ben.
Hi Benjamin, [auto build test ERROR on powerpc/next] [also build test ERROR on v4.13-rc1 next-20170717] [if your patch is applied to the wrong git tree, please drop us a note to help improve the system] url: https://github.com/0day-ci/linux/commits/Benjamin-Herrenschmidt/powerpc-mm-radix-Don-t-iterate-all-sets-when-flushing-the-PWC/20170715-044140 base: https://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux.git next config: powerpc-pasemi_defconfig (attached as .config) compiler: powerpc64-linux-gnu-gcc (Debian 6.1.1-9) 6.1.1 20160705 reproduce: wget https://raw.githubusercontent.com/01org/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross chmod +x ~/bin/make.cross # save the attached .config to linux build tree make.cross ARCH=powerpc All error/warnings (new ones prefixed by >>): In file included from include/asm-generic/bug.h:4:0, from arch/powerpc/include/asm/bug.h:127, from include/linux/bug.h:4, from include/linux/mmdebug.h:4, from include/linux/mm.h:8, from arch/powerpc/mm/tlb-radix.c:12: arch/powerpc/mm/tlb-radix.c: In function 'radix__flush_tlb_collapsed_pmd': >> include/linux/compiler.h:529:38: error: call to '__compiletime_assert_378' declared with attribute error: BUILD_BUG failed _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) ^ include/linux/compiler.h:512:4: note: in definition of macro '__compiletime_assert' prefix ## suffix(); \ ^~~~~~ include/linux/compiler.h:529:2: note: in expansion of macro '_compiletime_assert' _compiletime_assert(condition, msg, __compiletime_assert_, __LINE__) ^~~~~~~~~~~~~~~~~~~ include/linux/bug.h:54:37: note: in expansion of macro 'compiletime_assert' #define BUILD_BUG_ON_MSG(cond, msg) compiletime_assert(!(cond), msg) ^~~~~~~~~~~~~~~~~~ include/linux/bug.h:88:21: note: in expansion of macro 'BUILD_BUG_ON_MSG' #define BUILD_BUG() BUILD_BUG_ON_MSG(1, "BUILD_BUG failed") ^~~~~~~~~~~~~~~~ >> include/linux/huge_mm.h:218:27: note: in expansion of macro 'BUILD_BUG' #define HPAGE_PMD_SIZE ({ BUILD_BUG(); 0; }) ^~~~~~~~~ >> arch/powerpc/mm/tlb-radix.c:378:15: note: in expansion of macro 'HPAGE_PMD_SIZE' end = addr + HPAGE_PMD_SIZE; ^~~~~~~~~~~~~~ vim +/HPAGE_PMD_SIZE +378 arch/powerpc/mm/tlb-radix.c 353 354 void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr) 355 { 356 int local = mm_is_thread_local(mm); 357 unsigned long ap = mmu_get_ap(mmu_virtual_psize); 358 unsigned long pid, end; 359 360 361 pid = mm ? mm->context.id : 0; 362 if (unlikely(pid == MMU_NO_CONTEXT)) 363 goto no_context; 364 365 /* 4k page size, just blow the world */ 366 if (PAGE_SIZE == 0x1000) { 367 radix__flush_all_mm(mm); 368 return; 369 } 370 371 /* Otherwise first do the PWC */ 372 if (local) 373 _tlbiel_pid(pid, RIC_FLUSH_PWC); 374 else 375 _tlbie_pid(pid, RIC_FLUSH_PWC); 376 377 /* Then iterate the pages */ > 378 end = addr + HPAGE_PMD_SIZE; 379 for (; addr < end; addr += PAGE_SIZE) { 380 if (local) 381 _tlbiel_va(addr, pid, ap, RIC_FLUSH_TLB); 382 else 383 _tlbie_va(addr, pid, ap, RIC_FLUSH_TLB); 384 } 385 no_context: 386 preempt_enable(); 387 } 388 --- 0-DAY kernel test infrastructure Open Source Technology Center https://lists.01.org/pipermail/kbuild-all Intel Corporation
diff --git a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h b/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h index 7196999..9b433a6 100644 --- a/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h +++ b/arch/powerpc/include/asm/book3s/64/tlbflush-radix.h @@ -36,6 +36,7 @@ extern void radix__flush_tlb_page_psize(struct mm_struct *mm, unsigned long vmad #define radix__flush_tlb_page_psize(mm,addr,p) radix__local_flush_tlb_page_psize(mm,addr,p) #endif extern void radix__flush_tlb_pwc(struct mmu_gather *tlb, unsigned long addr); +extern void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr); extern void radix__flush_tlb_lpid_va(unsigned long lpid, unsigned long gpa, unsigned long page_size); extern void radix__flush_tlb_lpid(unsigned long lpid); diff --git a/arch/powerpc/mm/pgtable-radix.c b/arch/powerpc/mm/pgtable-radix.c index c28165d..83d70f7 100644 --- a/arch/powerpc/mm/pgtable-radix.c +++ b/arch/powerpc/mm/pgtable-radix.c @@ -706,9 +706,12 @@ pmd_t radix__pmdp_collapse_flush(struct vm_area_struct *vma, unsigned long addre */ pmd = *pmdp; pmd_clear(pmdp); + /*FIXME!! Verify whether we need this kick below */ kick_all_cpus_sync(); - flush_tlb_range(vma, address, address + HPAGE_PMD_SIZE); + + radix__flush_tlb_collapsed_pmd(vma->vm_mm, address); + return pmd; } diff --git a/arch/powerpc/mm/tlb-radix.c b/arch/powerpc/mm/tlb-radix.c index f65c928..73d3fbf 100644 --- a/arch/powerpc/mm/tlb-radix.c +++ b/arch/powerpc/mm/tlb-radix.c @@ -267,11 +267,7 @@ void radix__flush_tlb_range(struct vm_area_struct *vma, unsigned long start, { struct mm_struct *mm = vma->vm_mm; - /* - * This is currently used when collapsing THPs so we need to - * flush the PWC. We should fix this. - */ - radix__flush_all_mm(mm); + radix__flush_tlb_mm(mm); } EXPORT_SYMBOL(radix__flush_tlb_range); @@ -350,6 +346,41 @@ void radix__flush_tlb_range_psize(struct mm_struct *mm, unsigned long start, preempt_enable(); } +void radix__flush_tlb_collapsed_pmd(struct mm_struct *mm, unsigned long addr) +{ + int local = mm_is_thread_local(mm); + unsigned long ap = mmu_get_ap(mmu_virtual_psize); + unsigned long pid, end; + + + pid = mm ? mm->context.id : 0; + if (unlikely(pid == MMU_NO_CONTEXT)) + goto no_context; + + /* 4k page size, just blow the world */ + if (PAGE_SIZE == 0x1000) { + radix__flush_all_mm(mm); + return; + } + + /* Otherwise first do the PWC */ + if (local) + _tlbiel_pid(pid, RIC_FLUSH_PWC); + else + _tlbie_pid(pid, RIC_FLUSH_PWC); + + /* Then iterate the pages */ + end = addr + HPAGE_PMD_SIZE; + for (; addr < end; addr += PAGE_SIZE) { + if (local) + _tlbiel_va(addr, pid, ap, RIC_FLUSH_TLB); + else + _tlbie_va(addr, pid, ap, RIC_FLUSH_TLB); + } +no_context: + preempt_enable(); +} + void radix__flush_tlb_lpid_va(unsigned long lpid, unsigned long gpa, unsigned long page_size) {
We do that because it's used by THP pmd collapsing, so use instead a dedicated flush function. Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org> --- .../powerpc/include/asm/book3s/64/tlbflush-radix.h | 1 + arch/powerpc/mm/pgtable-radix.c | 5 ++- arch/powerpc/mm/tlb-radix.c | 41 +++++++++++++++++++--- 3 files changed, 41 insertions(+), 6 deletions(-)