diff options
| author | Mel Gorman | 2015-06-30 14:57:09 -0700 |
|---|---|---|
| committer | Linus Torvalds | 2015-06-30 19:44:56 -0700 |
| commit | 54608c3f3a448f1e042f5d9f3b873cc8dc022f27 (patch) | |
| tree | 410305a0ade6719f350a8c5f2456cec85c4e462a /mm | |
| parent | 7e18adb4f80bea90d30b62158694d97c31f71d37 (diff) | |
mm: meminit: minimise number of pfn->page lookups during initialisation
Deferred struct page initialisation is using pfn_to_page() on every PFN
unnecessarily. This patch minimises the number of lookups and scheduler
checks.
Signed-off-by: Mel Gorman <mgorman@suse.de>
Tested-by: Nate Zimmer <nzimmer@sgi.com>
Tested-by: Waiman Long <waiman.long@hp.com>
Tested-by: Daniel J Blueman <daniel@numascale.com>
Acked-by: Pekka Enberg <penberg@kernel.org>
Cc: Robin Holt <robinmholt@gmail.com>
Cc: Nate Zimmer <nzimmer@sgi.com>
Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Waiman Long <waiman.long@hp.com>
Cc: Scott Norton <scott.norton@hp.com>
Cc: "Luck, Tony" <tony.luck@intel.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'mm')
| -rw-r--r-- | mm/page_alloc.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/mm/page_alloc.c b/mm/page_alloc.c index c30f5a0535fd..0f770cc13450 100644 --- a/mm/page_alloc.c +++ b/mm/page_alloc.c @@ -1091,6 +1091,7 @@ void __defermem_init deferred_init_memmap(int nid) for_each_mem_pfn_range(i, nid, &walk_start, &walk_end, NULL) { unsigned long pfn, end_pfn; + struct page *page = NULL; end_pfn = min(walk_end, zone_end_pfn(zone)); pfn = first_init_pfn; @@ -1100,13 +1101,32 @@ void __defermem_init deferred_init_memmap(int nid) pfn = zone->zone_start_pfn; for (; pfn < end_pfn; pfn++) { - struct page *page; - - if (!pfn_valid(pfn)) + if (!pfn_valid_within(pfn)) continue; - if (!meminit_pfn_in_nid(pfn, nid, &nid_init_state)) + /* + * Ensure pfn_valid is checked every + * MAX_ORDER_NR_PAGES for memory holes + */ + if ((pfn & (MAX_ORDER_NR_PAGES - 1)) == 0) { + if (!pfn_valid(pfn)) { + page = NULL; + continue; + } + } + + if (!meminit_pfn_in_nid(pfn, nid, &nid_init_state)) { + page = NULL; continue; + } + + /* Minimise pfn page lookups and scheduler checks */ + if (page && (pfn & (MAX_ORDER_NR_PAGES - 1)) != 0) { + page++; + } else { + page = pfn_to_page(pfn); + cond_resched(); + } if (page->flags) { VM_BUG_ON(page_zone(page) != zone); @@ -1116,7 +1136,6 @@ void __defermem_init deferred_init_memmap(int nid) __init_single_page(page, pfn, zid, nid); __free_pages_boot_core(page, pfn, 0); nr_pages++; - cond_resched(); } first_init_pfn = max(end_pfn, first_init_pfn); } |