mm: eliminate "expecting prototype" kernel-doc warnings

Fix stray kernel-doc warnings in mm/ due to mis-typed or missing function
names.

Quietens these kernel-doc warnings:

  mm/mmu_gather.c:264: warning: expecting prototype for tlb_gather_mmu(). Prototype was for __tlb_gather_mmu() instead
  mm/oom_kill.c:180: warning: expecting prototype for Check whether unreclaimable slab amount is greater than(). Prototype was for should_dump_unreclaim_slab() instead
  mm/shuffle.c:155: warning: expecting prototype for shuffle_free_memory(). Prototype was for __shuffle_free_memory() instead

Link: https://lkml.kernel.org/r/20210411210642.11362-1-rdunlap@infradead.org
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Reviewed-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

mm/mmu_gather.c

@@ -249,16 +249,6 @@ void tlb_flush_mmu(struct mmu_gather *tlb)
 	tlb_flush_mmu_free(tlb);
 }
 
-/**
- * tlb_gather_mmu - initialize an mmu_gather structure for page-table tear-down
- * @tlb: the mmu_gather structure to initialize
- * @mm: the mm_struct of the target address space
- * @fullmm: @mm is without users and we're going to destroy the full address
- *	    space (exit/execve)
- *
- * Called to initialize an (on-stack) mmu_gather structure for page-table
- * tear-down from @mm.
- */
 static void __tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
 			     bool fullmm)
 {
@@ -283,11 +273,30 @@ static void __tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm,
 	inc_tlb_flush_pending(tlb->mm);
 }
 
+/**
+ * tlb_gather_mmu - initialize an mmu_gather structure for page-table tear-down
+ * @tlb: the mmu_gather structure to initialize
+ * @mm: the mm_struct of the target address space
+ *
+ * Called to initialize an (on-stack) mmu_gather structure for page-table
+ * tear-down from @mm.
+ */
 void tlb_gather_mmu(struct mmu_gather *tlb, struct mm_struct *mm)
 {
 	__tlb_gather_mmu(tlb, mm, false);
 }
 
+/**
+ * tlb_gather_mmu_fullmm - initialize an mmu_gather structure for page-table tear-down
+ * @tlb: the mmu_gather structure to initialize
+ * @mm: the mm_struct of the target address space
+ *
+ * In this case, @mm is without users and we're going to destroy the
+ * full address space (exit/execve).
+ *
+ * Called to initialize an (on-stack) mmu_gather structure for page-table
+ * tear-down from @mm.
+ */
 void tlb_gather_mmu_fullmm(struct mmu_gather *tlb, struct mm_struct *mm)
 {
 	__tlb_gather_mmu(tlb, mm, true);

mm/oom_kill.c

@@ -170,7 +170,7 @@ static bool oom_unkillable_task(struct task_struct *p)
 	return false;
 }
 
-/**
+/*
  * Check whether unreclaimable slab amount is greater than
  * all user memory(LRU pages).
  * dump_unreclaimable_slab() could help in the case that

mm/shuffle.c

@@ -147,8 +147,8 @@ void __meminit __shuffle_zone(struct zone *z)
 	spin_unlock_irqrestore(&z->lock, flags);
 }
 
-/**
- * shuffle_free_memory - reduce the predictability of the page allocator
+/*
+ * __shuffle_free_memory - reduce the predictability of the page allocator
  * @pgdat: node page data
  */
 void __meminit __shuffle_free_memory(pg_data_t *pgdat)