This is a note to let you know that I've just added the patch titled sparc64: Use kernel page tables for vmemmap. to the 3.17-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: sparc64-use-kernel-page-tables-for-vmemmap.patch and it can be found in the queue-3.17 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From foo@baz Tue Oct 28 11:21:07 CST 2014 From: "David S. Miller" <davem@xxxxxxxxxxxxx> Date: Wed, 24 Sep 2014 21:20:14 -0700 Subject: sparc64: Use kernel page tables for vmemmap. From: "David S. Miller" <davem@xxxxxxxxxxxxx> [ Upstream commit c06240c7f5c39c83dfd7849c0770775562441b96 ] For sparse memory configurations, the vmemmap array behaves terribly and it takes up an inordinate amount of space in the BSS section of the kernel image unconditionally. Just build huge PMDs and look them up just like we do for TLB misses in the vmalloc area. Kernel BSS shrinks by about 2MB. Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Acked-by: Bob Picco <bob.picco@xxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- arch/sparc/kernel/ktlb.S | 9 +---- arch/sparc/mm/init_64.c | 72 ++++++++++++++++++++++------------------------- arch/sparc/mm/init_64.h | 11 ------- 3 files changed, 36 insertions(+), 56 deletions(-) --- a/arch/sparc/kernel/ktlb.S +++ b/arch/sparc/kernel/ktlb.S @@ -186,13 +186,8 @@ kvmap_dtlb_load: #ifdef CONFIG_SPARSEMEM_VMEMMAP kvmap_vmemmap: - sub %g4, %g5, %g5 - srlx %g5, ILOG2_4MB, %g5 - sethi %hi(vmemmap_table), %g1 - sllx %g5, 3, %g5 - or %g1, %lo(vmemmap_table), %g1 - ba,pt %xcc, kvmap_dtlb_load - ldx [%g1 + %g5], %g5 + KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_dtlb_longpath) + ba,a,pt %xcc, kvmap_dtlb_load #endif kvmap_dtlb_nonlinear: --- a/arch/sparc/mm/init_64.c +++ b/arch/sparc/mm/init_64.c @@ -2261,18 +2261,9 @@ unsigned long _PAGE_CACHE __read_mostly; EXPORT_SYMBOL(_PAGE_CACHE); #ifdef CONFIG_SPARSEMEM_VMEMMAP -unsigned long vmemmap_table[VMEMMAP_SIZE]; - -static long __meminitdata addr_start, addr_end; -static int __meminitdata node_start; - int __meminit vmemmap_populate(unsigned long vstart, unsigned long vend, int node) { - unsigned long phys_start = (vstart - VMEMMAP_BASE); - unsigned long phys_end = (vend - VMEMMAP_BASE); - unsigned long addr = phys_start & VMEMMAP_CHUNK_MASK; - unsigned long end = VMEMMAP_ALIGN(phys_end); unsigned long pte_base; pte_base = (_PAGE_VALID | _PAGE_SZ4MB_4U | @@ -2283,47 +2274,52 @@ int __meminit vmemmap_populate(unsigned _PAGE_CP_4V | _PAGE_CV_4V | _PAGE_P_4V | _PAGE_W_4V); - for (; addr < end; addr += VMEMMAP_CHUNK) { - unsigned long *vmem_pp = - vmemmap_table + (addr >> VMEMMAP_CHUNK_SHIFT); - void *block; + pte_base |= _PAGE_PMD_HUGE; - if (!(*vmem_pp & _PAGE_VALID)) { - block = vmemmap_alloc_block(1UL << ILOG2_4MB, node); - if (!block) + vstart = vstart & PMD_MASK; + vend = ALIGN(vend, PMD_SIZE); + for (; vstart < vend; vstart += PMD_SIZE) { + pgd_t *pgd = pgd_offset_k(vstart); + unsigned long pte; + pud_t *pud; + pmd_t *pmd; + + if (pgd_none(*pgd)) { + pud_t *new = vmemmap_alloc_block(PAGE_SIZE, node); + + if (!new) return -ENOMEM; + pgd_populate(&init_mm, pgd, new); + } - *vmem_pp = pte_base | __pa(block); + pud = pud_offset(pgd, vstart); + if (pud_none(*pud)) { + pmd_t *new = vmemmap_alloc_block(PAGE_SIZE, node); - /* check to see if we have contiguous blocks */ - if (addr_end != addr || node_start != node) { - if (addr_start) - printk(KERN_DEBUG " [%lx-%lx] on node %d\n", - addr_start, addr_end-1, node_start); - addr_start = addr; - node_start = node; - } - addr_end = addr + VMEMMAP_CHUNK; + if (!new) + return -ENOMEM; + pud_populate(&init_mm, pud, new); } - } - return 0; -} -void __meminit vmemmap_populate_print_last(void) -{ - if (addr_start) { - printk(KERN_DEBUG " [%lx-%lx] on node %d\n", - addr_start, addr_end-1, node_start); - addr_start = 0; - addr_end = 0; - node_start = 0; + pmd = pmd_offset(pud, vstart); + + pte = pmd_val(*pmd); + if (!(pte & _PAGE_VALID)) { + void *block = vmemmap_alloc_block(PMD_SIZE, node); + + if (!block) + return -ENOMEM; + + pmd_val(*pmd) = pte_base | __pa(block); + } } + + return 0; } void vmemmap_free(unsigned long start, unsigned long end) { } - #endif /* CONFIG_SPARSEMEM_VMEMMAP */ static void prot_init_common(unsigned long page_none, --- a/arch/sparc/mm/init_64.h +++ b/arch/sparc/mm/init_64.h @@ -31,15 +31,4 @@ extern unsigned long kern_locked_tte_dat void prom_world(int enter); -#ifdef CONFIG_SPARSEMEM_VMEMMAP -#define VMEMMAP_CHUNK_SHIFT 22 -#define VMEMMAP_CHUNK (1UL << VMEMMAP_CHUNK_SHIFT) -#define VMEMMAP_CHUNK_MASK ~(VMEMMAP_CHUNK - 1UL) -#define VMEMMAP_ALIGN(x) (((x)+VMEMMAP_CHUNK-1UL)&VMEMMAP_CHUNK_MASK) - -#define VMEMMAP_SIZE ((((1UL << MAX_PHYSADDR_BITS) >> PAGE_SHIFT) * \ - sizeof(struct page)) >> VMEMMAP_CHUNK_SHIFT) -extern unsigned long vmemmap_table[VMEMMAP_SIZE]; -#endif - #endif /* _SPARC64_MM_INIT_H */ Patches currently in stable-queue which might be from davem@xxxxxxxxxxxxx are queue-3.17/sparc64-adjust-vmalloc-region-size-based-upon-available-virtual-address-bits.patch queue-3.17/sparc64-fix-fpu-register-corruption-with-aes-crypto-offload.patch queue-3.17/sparc64-move-request_irq-from-ldc_bind-to-ldc_alloc.patch queue-3.17/sparc32-dma_alloc_coherent-must-honour-gfp-flags.patch queue-3.17/sparc64-kill-unnecessary-tables-and-increase-max_banks.patch queue-3.17/sparc-let-memset-return-the-address-argument.patch queue-3.17/sparc64-use-kernel-page-tables-for-vmemmap.patch queue-3.17/sparc64-sparse-irq.patch queue-3.17/sparc64-fix-physical-memory-management-regressions-with-large-max_phys_bits.patch queue-3.17/sparc64-fix-lockdep-warnings-on-reboot-on-ultra-5.patch queue-3.17/sparc64-switch-to-4-level-page-tables.patch queue-3.17/sparc64-sun4v-tlb-error-power-off-events.patch queue-3.17/sparc64-increase-size-of-boot-string-to-1024-bytes.patch queue-3.17/sparc64-find_node-adjustment.patch queue-3.17/sparc64-fix-reversed-start-end-in-flush_tlb_kernel_range.patch queue-3.17/sparc64-increase-max_phys_address_bits-to-53.patch queue-3.17/sparc64-define-va-hole-at-run-time-rather-than-at-compile-time.patch queue-3.17/sparc64-fix-register-corruption-in-top-most-kernel-stack-frame-during-boot.patch queue-3.17/sparc64-support-m6-and-m7-for-building-cpu-distribution-map.patch queue-3.17/sparc64-cpu-hardware-caps-support-for-sparc-m6-and-m7.patch queue-3.17/sparc64-do-not-define-thread-fpregs-save-area-as-zero-length-array.patch queue-3.17/sparc64-t5-pmu.patch queue-3.17/sparc64-adjust-ktsb-assembler-to-support-larger-physical-addresses.patch queue-3.17/sparc64-implement-__get_user_pages_fast.patch queue-3.17/sparc64-fix-corrupted-thread-fault-code.patch queue-3.17/sparc64-fix-hibernation-code-refrence-to-page_offset.patch queue-3.17/sparc64-correctly-recognise-m6-and-m7-cpu-type.patch -- To unsubscribe from this list: send the line "unsubscribe stable" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html