diff mbox series

[072/128] mm/swapfile.c: use prandom_u32_max()

Message ID	20200602044919.X2xGegOOR%akpm@linux-foundation.org (mailing list archive)
State	New, archived
Headers	show Return-Path: <SRS0=y6BJ=7P=kvack.org=owner-linux-mm@kernel.org> DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1DBAC20734 Date: Mon, 01 Jun 2020 21:49:19 -0700 From: Andrew Morton <akpm@linux-foundation.org> To: akpm@linux-foundation.org, hughd@google.com, linux-mm@kvack.org, mhocko@suse.com, minchan@kernel.org, mm-commits@vger.kernel.org, tim.c.chen@linux.intel.com, torvalds@linux-foundation.org, ying.huang@intel.com Subject: [patch 072/128] mm/swapfile.c: use prandom_u32_max() Message-ID: <20200602044919.X2xGegOOR%akpm@linux-foundation.org> In-Reply-To: <20200601214457.919c35648e96a2b46b573fe1@linux-foundation.org> User-Agent: s-nail v14.8.16 Sender: owner-linux-mm@kvack.org Precedence: bulk
Series	[001/128] squashfs: migrate from ll_rw_block usage to BIO \| expand [001/128] squashfs: migrate from ll_rw_block usage to BIO [002/128] ocfs2: add missing annotation for dlm_empty_lockres() [003/128] ocfs2: mount shared volume without ha stack [004/128] arch/parisc/include/asm/pgtable.h: remove unused `old_pte' [005/128] vfs: track per-sb writeback errors and report them to syncfs [006/128] fs/buffer.c: record blockdev write errors in super_block that it backs [007/128] usercopy: mark dma-kmalloc caches as usercopy caches [008/128] mm/slub.c: fix corrupted freechain in deactivate_slab() [009/128] slub: Remove userspace notifier for cache add/remove [010/128] slub: remove kmalloc under list_lock from list_slab_objects() V2 [011/128] mm/slub: fix stack overruns with SLUB_STATS [012/128] Documentation/vm/slub.rst: s/Toggle/Enable/ [013/128] mm, dump_page(): do not crash with invalid mapping pointer [014/128] mm: move readahead prototypes from mm.h [015/128] mm: return void from various readahead functions [016/128] mm: ignore return value of ->readpages [017/128] mm: move readahead nr_pages check into read_pages [018/128] mm: add new readahead_control API [019/128] mm: use readahead_control to pass arguments [020/128] mm: rename various 'offset' parameters to 'index' [021/128] mm: rename readahead loop variable to 'i' [022/128] mm: remove 'page_offset' from readahead loop [023/128] mm: put readahead pages in cache earlier [024/128] mm: add readahead address space operation [025/128] mm: move end_index check out of readahead loop [026/128] mm: add page_cache_readahead_unbounded [027/128] mm: document why we don't set PageReadahead [028/128] mm: use memalloc_nofs_save in readahead path [029/128] fs: convert mpage_readpages to mpage_readahead [030/128] btrfs: convert from readpages to readahead [031/128] erofs: convert uncompressed files from readpages to readahead [032/128] erofs: convert compressed files from readpages to readahead [033/128] ext4: convert from readpages to readahead [034/128] ext4: pass the inode to ext4_mpage_readpages [035/128] f2fs: convert from readpages to readahead [036/128] f2fs: pass the inode to f2fs_mpage_readpages [037/128] fuse: convert from readpages to readahead [038/128] iomap: convert from readpages to readahead [039/128] include/linux/pagemap.h: introduce attach/detach_page_private [040/128] md: remove __clear_page_buffers and use attach/detach_page_private [041/128] btrfs: use attach/detach_page_private [042/128] fs/buffer.c: use attach/detach_page_private [043/128] f2fs: use attach/detach_page_private [044/128] iomap: use attach/detach_page_private [045/128] ntfs: replace attach_page_buffers with attach_page_private [046/128] orangefs: use attach/detach_page_private [047/128] buffer_head.h: remove attach_page_buffers [048/128] mm/migrate.c: call detach_page_private to cleanup code [049/128] mm_types.h: change set_page_private to inline function [050/128] mm/filemap.c: remove misleading comment [051/128] mm/page-writeback.c: remove unused variable [052/128] mm/writeback: replace PF_LESS_THROTTLE with PF_LOCAL_THROTTLE [053/128] mm/writeback: discard NR_UNSTABLE_NFS, use NR_WRITEBACK instead [054/128] mm/gup.c: update the documentation [055/128] mm/gup: introduce pin_user_pages_unlocked [056/128] ivtv: convert get_user_pages() --> pin_user_pages() [057/128] mm/gup.c: further document vma_permits_fault() [058/128] mm/swapfile: use list_{prev,next}_entry() instead of open-coding [059/128] mm/swap_state: fix a data race in swapin_nr_pages [060/128] mm: swap: properly update readahead statistics in unuse_pte_range() [061/128] mm/swapfile.c: offset is only used when there is more slots [062/128] mm/swapfile.c: explicitly show ssd/non-ssd is handled mutually exclusive [063/128] mm/swapfile.c: remove the unnecessary goto for SSD case [064/128] mm/swapfile.c: simplify the calculation of n_goal [065/128] mm/swapfile.c: remove the extra check in scan_swap_map_slots() [066/128] mm/swapfile.c: found_free could be represented by (tmp < max) [067/128] mm/swapfile.c: tmp is always smaller than max [068/128] mm/swapfile.c: omit a duplicate code by compare tmp and max first [069/128] swap: try to scan more free slots even when fragmented [070/128] mm/swapfile.c: classify SWAP_MAP_XXX to make it more readable [071/128] mm/swapfile.c: __swap_entry_free() always free 1 entry [072/128] mm/swapfile.c: use prandom_u32_max() [073/128] swap: reduce lock contention on swap cache from swap slots allocation [074/128] mm: swapfile: fix /proc/swaps heading and Size/Used/Priority alignment [075/128] include/linux/swap.h: delete meaningless __add_to_swap_cache() declaration [076/128] mm, memcg: add workingset_restore in memory.stat [077/128] mm: memcontrol: simplify value comparison between count and limit [078/128] memcg: expose root cgroup's memory.stat [079/128] mm/memcg: prepare for swap over-high accounting and penalty calculation [080/128] mm/memcg: move penalty delay clamping out of calculate_high_delay() [081/128] mm/memcg: move cgroup high memory limit setting into struct page_counter [082/128] mm/memcg: automatically penalize tasks with high swap use [083/128] memcg: fix memcg_kmem_bypass() for remote memcg charging [084/128] x86: mm: ptdump: calculate effective permissions correctly [085/128] mm: ptdump: expand type of 'val' in note_page() [086/128] /proc/PID/smaps: Add PMD migration entry parsing [087/128] mm/memory: remove unnecessary pte_devmap case in copy_one_pte() [088/128] mm, memory_failure: don't send BUS_MCEERR_AO for action required error [089/128] x86/hyperv: use vmalloc_exec for the hypercall page [090/128] x86: fix vmap arguments in map_irq_stack [091/128] staging: android: ion: use vmap instead of vm_map_ram [092/128] staging: media: ipu3: use vmap instead of reimplementing it [093/128] dma-mapping: use vmap insted of reimplementing it [094/128] powerpc: add an ioremap_phb helper [095/128] powerpc: remove __ioremap_at and __iounmap_at [096/128] mm: remove __get_vm_area [097/128] mm: unexport unmap_kernel_range_noflush [098/128] mm: rename CONFIG_PGTABLE_MAPPING to CONFIG_ZSMALLOC_PGTABLE_MAPPING [099/128] mm: only allow page table mappings for built-in zsmalloc [100/128] mm: pass addr as unsigned long to vb_free [101/128] mm: remove vmap_page_range_noflush and vunmap_page_range [102/128] mm: rename vmap_page_range to map_kernel_range [103/128] mm: don't return the number of pages from map_kernel_range{,_noflush} [104/128] mm: remove map_vm_range [105/128] mm: remove unmap_vmap_area [106/128] mm: remove the prot argument from vm_map_ram [107/128] mm: enforce that vmap can't map pages executable [108/128] gpu/drm: remove the powerpc hack in drm_legacy_sg_alloc [109/128] mm: remove the pgprot argument to __vmalloc [110/128] mm: remove the prot argument to __vmalloc_node [111/128] mm: remove both instances of __vmalloc_node_flags [112/128] mm: remove __vmalloc_node_flags_caller [113/128] mm: switch the test_vmalloc module to use __vmalloc_node [114/128] mm: remove vmalloc_user_node_flags [115/128] arm64: use __vmalloc_node in arch_alloc_vmap_stack [116/128] powerpc: use __vmalloc_node in alloc_vm_stack [117/128] s390: use __vmalloc_node in stack_alloc [118/128] mm: add functions to track page directory modifications [119/128] mm/vmalloc: track which page-table levels were modified [120/128] mm/ioremap: track which page-table levels were modified [121/128] x86/mm/64: implement arch_sync_kernel_mappings() [122/128] x86/mm/32: implement arch_sync_kernel_mappings() [123/128] mm: remove vmalloc_sync_(un)mappings() [124/128] x86/mm: remove vmalloc faulting [125/128] kasan: fix clang compilation warning due to stack protector [126/128] ubsan: entirely disable alignment checks under UBSAN_TRAP [127/128] mm/mm_init.c: report kasan-tag information stored in page->flags [128/128] kasan: move kasan_report() into report.c

Commit Message

Andrew Morton June 2, 2020, 4:49 a.m. UTC

From: Huang Ying <ying.huang@intel.com>
Subject: mm/swapfile.c: use prandom_u32_max()

To improve the code readability and take advantage of the common
implementation.

Link: http://lkml.kernel.org/r/20200512081013.520201-1-ying.huang@intel.com
Signed-off-by: "Huang, Ying" <ying.huang@intel.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Tim Chen <tim.c.chen@linux.intel.com>
Cc: Hugh Dickins <hughd@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
---

 mm/swapfile.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff mbox series

Patch

--- a/mm/swapfile.c~mm-swap-use-prandom_u32_max
+++ a/mm/swapfile.c
@@ -3209,7 +3209,7 @@  SYSCALL_DEFINE2(swapon, const char __use
 		 * select a random position to start with to help wear leveling
 		 * SSD
 		 */
-		p->cluster_next = 1 + (prandom_u32() % p->highest_bit);
+		p->cluster_next = 1 + prandom_u32_max(p->highest_bit);
 		nr_cluster = DIV_ROUND_UP(maxpages, SWAPFILE_CLUSTER);
 
 		cluster_info = kvcalloc(nr_cluster, sizeof(*cluster_info),