If the kernel exports the vmmemap then we can use that symbol in crash to optimize access. vmmemap is just an array of page structs after all. This patch tries to: 1.) Get the "vmemmap" from the vmcore file. If we can use the "vmemmap", we implement the arm64_vmemmap_is_page_ptr and set it to machdep->is_page_ptr. 2.) We implement the fast page_to_pfn code in arm64_vmemmap_is_page_ptr. 3.) Dump "vmemmap" in "help -v". Test result: Test the patch: "[PATCH v3] add "files -n" command for an inode" https://lists.crash-utility.osci.io/archives/list/ devel(a)lists.crash-utility.osci.io/thread/CRLOQP534YKEQPTCXIWVDYK4NA7BOSUK/ Without the this patch: #files -n xxx (xxx is the inode of vmlinux which is 441M) This costed about 162 seconds. With the this patch: #files -n xxx (xxx is the inode of vmlinux which is 441M) This costed less then 1 second.

Signed-off-by: Huang Shijie <shijie(a)os.amperecomputing.com&gt; --- v2 --> v3: Use arm64_get_vmcoreinfo() to parse the "vmemmap" Dump it in "help -v" --- arm64.c | 25 +++++++++++++++++++++++++ defs.h | 1 + memory.c | 1 + 3 files changed, 27 insertions(+) diff --git a/arm64.c b/arm64.c index 57965c6..fd6e9f7 100644 --- a/arm64.c +++ b/arm64.c @@ -117,6 +117,28 @@ static void arm64_calc_kernel_start(void) ms->kimage_end = (sp ? sp->value : 0); } +static int +arm64_vmemmap_is_page_ptr(ulong addr, physaddr_t *phys) +{ + ulong size = SIZE(page); + ulong pfn, nr; + + + if (IS_SPARSEMEM() && (machdep->flags & VMEMMAP) && + (addr >= VMEMMAP_VADDR && addr <= VMEMMAP_END) && + !((addr - VMEMMAP_VADDR) % size)) { + + pfn = (addr - vt->vmemmap) / size; + nr = pfn_to_section_nr(pfn); + if (valid_section_nr(nr)) { + if (phys) + *phys = PTOB(pfn); + return TRUE; + } + } + return FALSE; +} + /* * Do all necessary machine-specific setup here. This is called several times * during initialization. @@ -382,6 +404,9 @@ arm64_init(int when) machdep->stacksize = ARM64_STACK_SIZE; machdep->flags |= VMEMMAP; + /* If vmemmap exists, it means kernel enabled CONFIG_SPARSEMEM_VMEMMAP */ + if (arm64_get_vmcoreinfo(&vt->vmemmap, "SYMBOL(vmemmap)", NUM_HEX)) + machdep->is_page_ptr = arm64_vmemmap_is_page_ptr; machdep->uvtop = arm64_uvtop; machdep->is_uvaddr = arm64_is_uvaddr; diff --git a/defs.h b/defs.h index 0558d13..bb775fd 100644 --- a/defs.h +++ b/defs.h @@ -2634,6 +2634,7 @@ struct vm_table { /* kernel VM-related data */ ulong max_mem_section_nr; ulong zero_paddr; ulong huge_zero_paddr; + ulong vmemmap;

Rewrite the arm64_get_vmcoreinfo_ul to arm64_get_vmcoreinfo, add a new parameter "base" for it. Also use it to simplify the arm64 code. Signed-off-by: Huang Shijie <shijie(a)os.amperecomputing.com&gt; --- v2 --> v3: Do not change the generic code, only change the arm64 code.

--- arm64.c | 99 +++++++++++++++++++++++---------------------------------- 1 file changed, 39 insertions(+), 60 deletions(-) diff --git a/arm64.c b/arm64.c index 2b6b0e5..57965c6 100644 --- a/arm64.c +++ b/arm64.c @@ -92,6 +92,7 @@ static void arm64_get_crash_notes(void); static void arm64_calc_VA_BITS(void); static int arm64_is_uvaddr(ulong, struct task_context *); static void arm64_calc_KERNELPACMASK(void); +static int arm64_get_vmcoreinfo(unsigned long *vaddr, const char *label, int base); struct kernel_range { unsigned long modules_vaddr, modules_end; @@ -124,7 +125,6 @@ void arm64_init(int when) { ulong value; - char *string; struct machine_specific *ms; #if defined(__x86_64__) @@ -160,11 +160,8 @@ arm64_init(int when) if (!ms->kimage_voffset && STREQ(pc->live_memsrc, "/dev/crash")) ioctl(pc->mfd, DEV_CRASH_ARCH_DATA, &ms->kimage_voffset); - if (!ms->kimage_voffset && - (string = pc->read_vmcoreinfo("NUMBER(kimage_voffset)"))) { - ms->kimage_voffset = htol(string, QUIET, NULL); - free(string); - } + if (!ms->kimage_voffset) + arm64_get_vmcoreinfo(&ms->kimage_voffset, "NUMBER(kimage_voffset)", NUM_HEX); if (ms->kimage_voffset || (ACTIVE() && (symbol_value_from_proc_kallsyms("kimage_voffset") != BADVAL))) { @@ -185,11 +182,8 @@ arm64_init(int when) if (kernel_symbol_exists("kimage_voffset")) machdep->flags |= NEW_VMEMMAP; - if (!machdep->pagesize && - (string = pc->read_vmcoreinfo("PAGESIZE"))) { - machdep->pagesize = atoi(string); - free(string); - } + if (!machdep->pagesize && arm64_get_vmcoreinfo(&value, "PAGESIZE", NUM_DEC)) + machdep->pagesize = (unsigned int)value; if (!machdep->pagesize) { /* @@ -443,9 +437,8 @@ arm64_init(int when) arm64_get_section_size_bits(); if (!machdep->max_physmem_bits) { - if ((string = pc->read_vmcoreinfo("NUMBER(MAX_PHYSMEM_BITS)"))) { - machdep->max_physmem_bits = atol(string); - free(string); + if (arm64_get_vmcoreinfo(&machdep->max_physmem_bits, "NUMBER(MAX_PHYSMEM_BITS)", NUM_DEC)) { + /* nothing */ } else if (machdep->machspec->VA_BITS == 52) /* guess */ machdep->max_physmem_bits = _MAX_PHYSMEM_BITS_52; else if (THIS_KERNEL_VERSION >= LINUX(3,17,0)) @@ -573,16 +566,28 @@ static int arm64_get_struct_page_max_shift(struct machine_specific *ms) } /* Return TRUE if we succeed, return FALSE on failure. */ -static int arm64_get_vmcoreinfo_ul(unsigned long *vaddr, const char* label) +static int +arm64_get_vmcoreinfo(unsigned long *vaddr, const char *label, int base) { + int err = 0; char *string = pc->read_vmcoreinfo(label); if (!string) return FALSE; - *vaddr = strtoul(string, NULL, 0); + switch (base) { + case NUM_HEX: + *vaddr = strtoul(string, NULL, 16); + break; + case NUM_DEC: + *vaddr = strtoul(string, NULL, 10); + break; + default: + err++; + error(INFO, "Unknown type:%#x, (NUM_HEX|NUM_DEC)\n", base); + } free(string); - return TRUE; + return err ? FALSE: TRUE; } /* @@ -594,21 +599,21 @@ static struct kernel_range *arm64_get_range_v5_18(struct machine_specific *ms) struct kernel_range *r = &tmp_range; /* Get the MODULES_VADDR ~ MODULES_END */ - if (!arm64_get_vmcoreinfo_ul(&r->modules_vaddr, "NUMBER(MODULES_VADDR)")) + if (!arm64_get_vmcoreinfo(&r->modules_vaddr, "NUMBER(MODULES_VADDR)", NUM_HEX)) return NULL; - if (!arm64_get_vmcoreinfo_ul(&r->modules_end, "NUMBER(MODULES_END)")) + if (!arm64_get_vmcoreinfo(&r->modules_end, "NUMBER(MODULES_END)", NUM_HEX)) return NULL; /* Get the VMEMMAP_START ~ VMEMMAP_END */ - if (!arm64_get_vmcoreinfo_ul(&r->vmemmap_vaddr, "NUMBER(VMEMMAP_START)")) + if (!arm64_get_vmcoreinfo(&r->vmemmap_vaddr, "NUMBER(VMEMMAP_START)", NUM_HEX)) return NULL; - if (!arm64_get_vmcoreinfo_ul(&r->vmemmap_end, "NUMBER(VMEMMAP_END)")) + if (!arm64_get_vmcoreinfo(&r->vmemmap_end, "NUMBER(VMEMMAP_END)", NUM_HEX)) return NULL; /* Get the VMALLOC_START ~ VMALLOC_END */ - if (!arm64_get_vmcoreinfo_ul(&r->vmalloc_start_addr, "NUMBER(VMALLOC_START)")) + if (!arm64_get_vmcoreinfo(&r->vmalloc_start_addr, "NUMBER(VMALLOC_START)", NUM_HEX)) return NULL; - if (!arm64_get_vmcoreinfo_ul(&r->vmalloc_end, "NUMBER(VMALLOC_END)")) + if (!arm64_get_vmcoreinfo(&r->vmalloc_end, "NUMBER(VMALLOC_END)", NUM_HEX)) return NULL; return r; @@ -888,12 +893,7 @@ range_failed: /* Get the size of struct page {} */ static void arm64_get_struct_page_size(struct machine_specific *ms) { - char *string; - - string = pc->read_vmcoreinfo("SIZE(page)"); - if (string) - ms->struct_page_size = atol(string); - free(string); + arm64_get_vmcoreinfo(&ms->struct_page_size, "SIZE(page)", NUM_DEC); } /* @@ -1469,16 +1469,12 @@ arm64_calc_phys_offset(void) physaddr_t paddr; ulong vaddr; struct syment *sp; - char *string; if ((machdep->flags & NEW_VMEMMAP) && ms->kimage_voffset && (sp = kernel_symbol_search("memstart_addr"))) { if (pc->flags & PROC_KCORE) { - if ((string = pc->read_vmcoreinfo("NUMBER(PHYS_OFFSET)"))) { - ms->phys_offset = htol(string, QUIET, NULL); - free(string); + if (arm64_get_vmcoreinfo(&ms->phys_offset, "NUMBER(PHYS_OFFSET)", NUM_HEX)) return; - } vaddr = symbol_value_from_proc_kallsyms("memstart_addr"); if (vaddr == BADVAL) vaddr = sp->value; @@ -1560,9 +1556,8 @@ arm64_get_section_size_bits(void) } else machdep->section_size_bits = _SECTION_SIZE_BITS; - if ((string = pc->read_vmcoreinfo("NUMBER(SECTION_SIZE_BITS)"))) { - machdep->section_size_bits = atol(string); - free(string); + if (arm64_get_vmcoreinfo(&machdep->section_size_bits, "NUMBER(SECTION_SIZE_BITS)", NUM_DEC)) { + /* nothing */ } else if (kt->ikconfig_flags & IKCONFIG_AVAIL) { if ((ret = get_kernel_config("CONFIG_MEMORY_HOTPLUG", NULL)) == IKCONFIG_Y) { if ((ret = get_kernel_config("CONFIG_HOTPLUG_SIZE_BITS", &string)) == IKCONFIG_STR) @@ -1581,15 +1576,11 @@ arm64_get_section_size_bits(void) static int arm64_kdump_phys_base(ulong *phys_offset) { - char *string; struct syment *sp; physaddr_t paddr; - if ((string = pc->read_vmcoreinfo("NUMBER(PHYS_OFFSET)"))) { - *phys_offset = htol(string, QUIET, NULL); - free(string); + if (arm64_get_vmcoreinfo(phys_offset, "NUMBER(PHYS_OFFSET)", NUM_HEX)) return TRUE; - } if ((machdep->flags & NEW_VMEMMAP) && machdep->machspec->kimage_voffset && @@ -4592,10 +4583,9 @@ static int arm64_set_va_bits_by_tcr(void) { ulong value; - char *string; - if ((string = pc->read_vmcoreinfo("NUMBER(TCR_EL1_T1SZ)")) || - (string = pc->read_vmcoreinfo("NUMBER(tcr_el1_t1sz)"))) { + if (arm64_get_vmcoreinfo(&value, "NUMBER(TCR_EL1_T1SZ)", NUM_HEX) || + arm64_get_vmcoreinfo(&value, "NUMBER(tcr_el1_t1sz)", NUM_HEX)) { /* See ARMv8 ARM for the description of * TCR_EL1.T1SZ and how it can be used * to calculate the vabits_actual @@ -4604,10 +4594,9 @@ arm64_set_va_bits_by_tcr(void) * Basically: * vabits_actual = 64 - T1SZ; */ - value = 64 - strtoll(string, NULL, 0); + value = 64 - value; if (CRASHDEBUG(1)) fprintf(fp, "vmcoreinfo : vabits_actual: %ld\n", value); - free(string); machdep->machspec->VA_BITS_ACTUAL = value; machdep->machspec->VA_BITS = value; machdep->machspec->VA_START = _VA_START(machdep->machspec->VA_BITS_ACTUAL); @@ -4623,13 +4612,8 @@ arm64_calc_VA_BITS(void) int bitval; struct syment *sp; ulong vabits_actual, value; - char *string; - if ((string = pc->read_vmcoreinfo("NUMBER(VA_BITS)"))) { - value = atol(string); - free(string); - machdep->machspec->CONFIG_ARM64_VA_BITS = value; - } + arm64_get_vmcoreinfo(&machdep->machspec->CONFIG_ARM64_VA_BITS, "NUMBER(VA_BITS)", NUM_DEC); if (kernel_symbol_exists("vabits_actual")) { if (pc->flags & PROC_KCORE) { @@ -4754,9 +4738,7 @@ arm64_calc_virtual_memory_ranges(void) ulong PUD_SIZE = UNINITIALIZED; if (!machdep->machspec->CONFIG_ARM64_VA_BITS) { - if ((string = pc->read_vmcoreinfo("NUMBER(VA_BITS)"))) { - value = atol(string); - free(string); + if (arm64_get_vmcoreinfo(&value, "NUMBER(VA_BITS)", NUM_DEC)) { machdep->machspec->CONFIG_ARM64_VA_BITS = value; } else if (kt->ikconfig_flags & IKCONFIG_AVAIL) { if ((ret = get_kernel_config("CONFIG_ARM64_VA_BITS", @@ -4852,11 +4834,8 @@ arm64_swp_offset(ulong pte) static void arm64_calc_KERNELPACMASK(void) { ulong value; - char *string; - if ((string = pc->read_vmcoreinfo("NUMBER(KERNELPACMASK)"))) { - value = htol(string, QUIET, NULL); - free(string); + if (arm64_get_vmcoreinfo(&value, "NUMBER(KERNELPACMASK)", NUM_HEX)) { machdep->machspec->CONFIG_ARM64_KERNELPACMASK = value; if (CRASHDEBUG(1)) fprintf(fp, "CONFIG_ARM64_KERNELPACMASK: %lx\n", value);