linux/mm
Zhen Lei 7bba8f0ea4 mm/mmap: optimize a branch judgment in ksys_mmap_pgoff()
Look at the pseudo code below.  It's very clear that, the judgement
"!is_file_hugepages(file)" at 3) is duplicated to the one at 1), we can
use "else if" to avoid it.  And the assignment "retval = -EINVAL" at 2) is
only needed by the branch 3), because "retval" will be overwritten at 4).

No functional change, but it can reduce the code size. Maybe more clearer?
Before:
text    data     bss     dec     hex filename
28733    1590       1   30324    7674 mm/mmap.o

After:
text    data     bss     dec     hex filename
28701    1590       1   30292    7654 mm/mmap.o

====pseudo code====:
	if (!(flags & MAP_ANONYMOUS)) {
		...
1)		if (is_file_hugepages(file))
			len = ALIGN(len, huge_page_size(hstate_file(file)));
2)		retval = -EINVAL;
3)		if (unlikely(flags & MAP_HUGETLB && !is_file_hugepages(file)))
			goto out_fput;
	} else if (flags & MAP_HUGETLB) {
		...
	}
	...

4)	retval = vm_mmap_pgoff(file, addr, len, prot, flags, pgoff);
out_fput:
	...
	return retval;

Signed-off-by: Zhen Lei <thunder.leizhen@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200705080112.1405-1-thunder.leizhen@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-08-07 11:33:26 -07:00
..
kasan mm: remove __ARCH_HAS_5LEVEL_HACK and include/asm-generic/5level-fixup.h 2020-06-04 19:06:21 -07:00
Kconfig docs: move nommu-mmap.txt to admin-guide and rename to ReST 2020-06-26 11:33:35 -06:00
Kconfig.debug treewide: replace '---help---' in Kconfig files with 'help' 2020-06-14 01:57:21 +09:00
Makefile mm: move lib/ioremap.c to mm/ 2020-08-07 11:33:26 -07:00
backing-dev.c writeback: remove struct bdi_writeback_congested 2020-07-08 17:05:53 -06:00
balloon_compaction.c mm/balloon_compaction: suppress allocation warnings 2019-09-04 07:42:01 -04:00
cleancache.c Driver Core and debugfs changes for 5.3-rc1 2019-07-12 12:24:03 -07:00
cma.c mm/cma.c: use exact_nid true to fix possible per-numa cma leak 2020-07-03 16:15:25 -07:00
cma.h debugfs: make sure we can remove u32_array files cleanly 2020-07-10 13:54:00 -07:00
cma_debug.c debugfs: make sure we can remove u32_array files cleanly 2020-07-10 13:54:00 -07:00
compaction.c mm, compaction: make capture control handling safe wrt interrupts 2020-06-26 00:27:36 -07:00
debug.c mm, dump_page: do not crash with bad compound_mapcount() 2020-08-07 11:33:23 -07:00
debug_page_ref.c
debug_vm_pgtable.c Documentation/mm: add descriptions for arch page table helpers 2020-08-07 11:33:23 -07:00
dmapool.c mm/dmapool.c: micro-optimisation remove unnecessary branch 2020-04-07 10:43:42 -07:00
early_ioremap.c mm/early_ioremap.c: use %pa to print resource_size_t variables 2020-01-31 10:30:38 -08:00
fadvise.c mm: return void from various readahead functions 2020-06-02 10:59:06 -07:00
failslab.c mm/failslab.c: by default, do not fail allocations with direct reclaim only 2019-07-12 11:05:43 -07:00
filemap.c mm: filemap: add missing FGP_ flags in kerneldoc comment for pagecache_get_page 2020-08-07 11:33:23 -07:00
frame_vector.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
frontswap.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
gup.c mm/gup.c: fix the comment of return value for populate_vma_page_range() 2020-08-07 11:33:23 -07:00
gup_benchmark.c mm/gup_benchmark: support pin_user_pages() and related calls 2020-04-02 09:35:27 -07:00
highmem.c mm, x86/mm: Untangle address space layout definitions from basic pgtable type definitions 2019-12-10 10:12:55 +01:00
hmm.c mm/hmm: provide the page mapping order in hmm_range_fault() 2020-07-10 16:24:28 -03:00
huge_memory.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
hugetlb.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
hugetlb_cgroup.c mm: use fallthrough; 2020-04-07 10:43:41 -07:00
hwpoison-inject.c mm/hwpoison-inject: use DEFINE_DEBUGFS_ATTRIBUTE to define debugfs fops 2019-12-01 12:59:09 -08:00
init-mm.c mmap locking API: add MMAP_LOCK_INITIALIZER 2020-06-09 09:39:14 -07:00
internal.h mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
interval_tree.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 248 2019-06-19 17:09:08 +02:00
ioremap.c mm: move p?d_alloc_track to separate header file 2020-08-07 11:33:26 -07:00
khugepaged.c khugepaged: fix null-pointer dereference due to race 2020-07-24 12:42:41 -07:00
kmemleak-test.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 333 2019-06-05 17:37:06 +02:00
kmemleak.c mm/kmemleak.c: use address-of operator on section symbols 2020-04-02 09:35:26 -07:00
ksm.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
list_lru.c mm/list_lru.c: Rename kvfree_rcu() to local variant 2020-06-29 11:59:25 -07:00
maccess.c maccess: rename probe_user_{read,write} to copy_{from,to}_user_nofault 2020-06-17 10:57:41 -07:00
madvise.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mapping_dirty_helpers.c mm/mapping_dirty_helpers: update huge page-table entry callbacks 2020-04-02 09:35:29 -07:00
memblock.c mm/memblock: expose only miminal interface to add/walk physmem 2020-07-10 15:08:09 +02:00
memcontrol.c mm: memcontrol: don't count limit-setting reclaim as memory pressure 2020-08-07 11:33:26 -07:00
memfd.c mm: page cache: store only head pages in i_pages 2019-09-24 15:54:08 -07:00
memory-failure.c mm/memory-failure: send SIGBUS(BUS_MCEERR_AR) only to current thread 2020-06-11 18:17:47 -07:00
memory.c mm/memory.c: make remap_pfn_range() reject unaligned addr 2020-08-07 11:33:26 -07:00
memory_hotplug.c mm/memory_hotplug.c: fix false softlockup during pfn range removal 2020-06-26 00:27:38 -07:00
mempolicy.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
mempool.c docs/core-api/mm: fix return value descriptions in mm/ 2019-03-05 21:07:20 -08:00
memremap.c mm/memremap: set caching mode for PCI P2PDMA memory to WC 2020-04-10 15:36:21 -07:00
memtest.c
migrate.c mm/migrate: fix migrate_pgmap_owner w/o CONFIG_MMU_NOTIFIER 2020-08-07 11:33:21 -07:00
mincore.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
mlock.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mm_init.c mm/mm_init.c: report kasan-tag information stored in page->flags 2020-06-02 10:59:12 -07:00
mmap.c mm/mmap: optimize a branch judgment in ksys_mmap_pgoff() 2020-08-07 11:33:26 -07:00
mmu_gather.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mmu_notifier.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mmzone.c
mprotect.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
mremap.c mm: document warning in move_normal_pmd() and make it warn only once 2020-07-13 11:37:39 -07:00
msync.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
nommu.c It's been a busy cycle for documentation - hopefully the busiest for a 2020-08-04 22:47:54 -07:00
oom_kill.c mm: memcg: convert vmstat slab counters to bytes 2020-08-07 11:33:24 -07:00
page-writeback.c mm/page-writeback: fix a typo in comment "effictive"->"effective" 2020-06-04 19:06:24 -07:00
page_alloc.c mm: memcontrol: account kernel stack per node 2020-08-07 11:33:25 -07:00
page_counter.c mm/page_counter.c: fix protection usage propagation 2020-08-07 11:33:26 -07:00
page_ext.c mm/page_ext.c: drop pfn_present() check when onlining 2020-04-07 10:43:40 -07:00
page_idle.c mm/page_idle.c: skip offline pages 2020-06-08 11:05:55 -07:00
page_io.c mm/page_io.c: use blk_io_schedule() for avoiding task hung in sync io 2020-08-07 11:33:24 -07:00
page_isolation.c mm: Allow to offline unmovable PageOffline() pages via MEM_GOING_OFFLINE 2020-06-04 15:36:52 -04:00
page_owner.c mm: rename gfpflags_to_migratetype to gfp_migratetype for same convention 2020-06-03 20:09:45 -07:00
page_poison.c mm/page_poison.c: fix a typo in a comment 2019-09-24 15:54:08 -07:00
page_reporting.c mm/page_reporting: add budget limit on how many pages can be reported per pass 2020-04-07 10:43:39 -07:00
page_reporting.h mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
page_vma_mapped.c mm/page_vma_mapped.c: explicitly compare pfn for normal, hugetlbfs and THP page 2020-01-31 10:30:38 -08:00
pagewalk.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
percpu-internal.h percpu: convert chunk hints to be based on pcpu_block_md 2019-03-13 12:25:31 -07:00
percpu-km.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu-stats.c percpu: update copyright emails to dennis@kernel.org 2020-04-01 10:09:12 -07:00
percpu-vm.c treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428 2019-06-05 17:37:16 +02:00
percpu.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
pgalloc-track.h mm: move p?d_alloc_track to separate header file 2020-08-07 11:33:26 -07:00
pgtable-generic.c mm: introduce include/linux/pgtable.h 2020-06-09 09:39:13 -07:00
process_vm_access.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
ptdump.c mmap locking API: use coccinelle to convert mmap_sem rwsem call sites 2020-06-09 09:39:14 -07:00
readahead.c mm: use memalloc_nofs_save in readahead path 2020-06-02 10:59:07 -07:00
rmap.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
rodata_test.c maccess: rename probe_kernel_{read,write} to copy_{from,to}_kernel_nofault 2020-06-17 10:57:41 -07:00
shmem.c tmpfs: support 64-bit inums per-sb 2020-08-07 11:33:24 -07:00
shuffle.c mm/shuffle: don't move pages between zones and don't read garbage memmaps 2020-08-07 11:33:21 -07:00
shuffle.h mm: adjust shuffle code to allow for future coalescing 2020-04-07 10:43:38 -07:00
slab.c mm: slab: rename (un)charge_slab_page() to (un)account_slab_page() 2020-08-07 11:33:25 -07:00
slab.h mm: slab: rename (un)charge_slab_page() to (un)account_slab_page() 2020-08-07 11:33:25 -07:00
slab_common.c mm: memcg/slab: use a single set of kmem_caches for all allocations 2020-08-07 11:33:25 -07:00
slob.c mm: memcg: convert vmstat slab counters to bytes 2020-08-07 11:33:24 -07:00
slub.c mm: slab: rename (un)charge_slab_page() to (un)account_slab_page() 2020-08-07 11:33:25 -07:00
sparse-vmemmap.c mm: don't include asm/pgtable.h if linux/mm.h is already included 2020-06-09 09:39:13 -07:00
sparse.c mm: remove unneeded includes of <asm/pgalloc.h> 2020-08-07 11:33:26 -07:00
swap.c treewide: Remove uninitialized_var() usage 2020-07-16 12:35:15 -07:00
swap_cgroup.c mm: memcontrol: make swap tracking an integral part of memory control 2020-06-03 20:09:48 -07:00
swap_slots.c mm/swap_slots.c: remove redundant check for swap_slot_cache_initialized 2020-08-07 11:33:24 -07:00
swap_state.c mm: swap: fix kerneldoc of swap_vma_readahead() 2020-08-07 11:33:24 -07:00
swapfile.c block: remove the bd_queue field from struct block_device 2020-07-01 08:08:20 -06:00
truncate.c mm/thp: allow dropping THP from page cache 2019-10-19 06:32:33 -04:00
usercopy.c usercopy: Avoid HIGHMEM pfn warning 2019-09-17 15:20:17 -07:00
userfaultfd.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
util.c mmap locking API: convert mmap_sem comments 2020-06-09 09:39:14 -07:00
vmacache.c kernel: better document the use_mm/unuse_mm API contract 2020-06-10 19:14:18 -07:00
vmalloc.c mm: move p?d_alloc_track to separate header file 2020-08-07 11:33:26 -07:00
vmpressure.c mm: vmpressure: use mem_cgroup_is_root API 2020-04-02 09:35:31 -07:00
vmscan.c mm: memcontrol: don't count limit-setting reclaim as memory pressure 2020-08-07 11:33:26 -07:00
vmstat.c mm: memcontrol: account kernel stack per node 2020-08-07 11:33:25 -07:00
workingset.c mm: memcg: convert vmstat slab counters to bytes 2020-08-07 11:33:24 -07:00
z3fold.c mm/z3fold: silence kmemleak false positives of slots 2020-05-28 11:35:40 -07:00
zbud.c mm: use false for bool variable 2020-06-04 19:06:24 -07:00
zpool.c zpool: add malloc_support_movable to zpool_driver 2019-09-24 15:54:12 -07:00
zsmalloc.c mm: reorder includes after introduction of linux/pgtable.h 2020-06-09 09:39:13 -07:00
zswap.c mm/zswap: allow setting default status, compressor and allocator in Kconfig 2020-04-07 10:43:41 -07:00