diff options
author | Robin Holt <holt@sgi.com> | 2006-04-13 15:34:45 -0700 |
---|---|---|
committer | Tony Luck <tony.luck@intel.com> | 2006-04-13 15:34:45 -0700 |
commit | ace1d816a13ff42d4f41989862552032f9c19853 (patch) | |
tree | 084277670a76f9a50449e82b308ecc7b881fd5ac /arch/ia64 | |
parent | 356a5c1c6fdfb8eed6dbb3979d90c7cc7060017a (diff) | |
download | kernel_samsung_smdk4412-ace1d816a13ff42d4f41989862552032f9c19853.zip kernel_samsung_smdk4412-ace1d816a13ff42d4f41989862552032f9c19853.tar.gz kernel_samsung_smdk4412-ace1d816a13ff42d4f41989862552032f9c19853.tar.bz2 |
[IA64] Make show_mem() skip holes in a pgdat
This patch modifies ia64's show_mem() to walk the vmem_map page tables and
rapidly skip forward across regions where the page tables are missing.
This prevents the pfn_valid() check from causing numerous unnecessary
page faults.
Without this patch on a 512 node 512 cpu system where every node has four
memory holes, the show_mem() call takes 1 hour 18 minutes. With this
patch, it takes less than 3 seconds.
Signed-off-by: Robin Holt <holt@sgi.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>
Diffstat (limited to 'arch/ia64')
-rw-r--r-- | arch/ia64/mm/discontig.c | 66 |
1 files changed, 65 insertions, 1 deletions
diff --git a/arch/ia64/mm/discontig.c b/arch/ia64/mm/discontig.c index ec9eeb8..b6bcc9f 100644 --- a/arch/ia64/mm/discontig.c +++ b/arch/ia64/mm/discontig.c @@ -519,6 +519,68 @@ void __cpuinit *per_cpu_init(void) } #endif /* CONFIG_SMP */ +#ifdef CONFIG_VIRTUAL_MEM_MAP +static inline int find_next_valid_pfn_for_pgdat(pg_data_t *pgdat, int i) +{ + unsigned long end_address, hole_next_pfn; + unsigned long stop_address; + + end_address = (unsigned long) &vmem_map[pgdat->node_start_pfn + i]; + end_address = PAGE_ALIGN(end_address); + + stop_address = (unsigned long) &vmem_map[ + pgdat->node_start_pfn + pgdat->node_spanned_pages]; + + do { + pgd_t *pgd; + pud_t *pud; + pmd_t *pmd; + pte_t *pte; + + pgd = pgd_offset_k(end_address); + if (pgd_none(*pgd)) { + end_address += PGDIR_SIZE; + continue; + } + + pud = pud_offset(pgd, end_address); + if (pud_none(*pud)) { + end_address += PUD_SIZE; + continue; + } + + pmd = pmd_offset(pud, end_address); + if (pmd_none(*pmd)) { + end_address += PMD_SIZE; + continue; + } + + pte = pte_offset_kernel(pmd, end_address); +retry_pte: + if (pte_none(*pte)) { + end_address += PAGE_SIZE; + pte++; + if ((end_address < stop_address) && + (end_address != ALIGN(end_address, 1UL << PMD_SHIFT))) + goto retry_pte; + continue; + } + /* Found next valid vmem_map page */ + break; + } while (end_address < stop_address); + + end_address = min(end_address, stop_address); + end_address = end_address - (unsigned long) vmem_map + sizeof(struct page) - 1; + hole_next_pfn = end_address / sizeof(struct page); + return hole_next_pfn - pgdat->node_start_pfn; +} +#else +static inline int find_next_valid_pfn_for_pgdat(pg_data_t *pgdat, int i) +{ + return i + 1; +} +#endif + /** * show_mem - give short summary of memory stats * @@ -547,8 +609,10 @@ void show_mem(void) struct page *page; if (pfn_valid(pgdat->node_start_pfn + i)) page = pfn_to_page(pgdat->node_start_pfn + i); - else + else { + i = find_next_valid_pfn_for_pgdat(pgdat, i) - 1; continue; + } if (PageReserved(page)) reserved++; else if (PageSwapCache(page)) |