mm: functions may simplify the use of return values

p4d_clear_huge may be optimized for void return type and function usage.
vunmap_p4d_range function saves a few steps here.

Link: https://lkml.kernel.org/r/20220507150630.90399-1-kunyu@nfschina.com
Signed-off-by: Li kunyu <kunyu@nfschina.com>
Cc: Dave Hansen <dave.hansen@linux.intel.com>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/arch/x86/mm/pgtable.c b/arch/x86/mm/pgtable.c
index f16059e..a932d77 100644 (file)
--- a/arch/x86/mm/pgtable.c
+++ b/arch/x86/mm/pgtable.c
@@ -686,9 +686,8 @@ int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
  *
  * No 512GB pages yet -- always return 0
  */
-int p4d_clear_huge(p4d_t *p4d)
+void p4d_clear_huge(p4d_t *p4d)
 {
-       return 0;
 }
 #endif
 

diff --git a/include/linux/pgtable.h b/include/linux/pgtable.h
index ecb4c76..3cdc16c 100644 (file)
--- a/include/linux/pgtable.h
+++ b/include/linux/pgtable.h
@@ -1448,16 +1448,13 @@ static inline int pmd_protnone(pmd_t pmd)
 
 #ifndef __PAGETABLE_P4D_FOLDED
 int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot);
-int p4d_clear_huge(p4d_t *p4d);
+void p4d_clear_huge(p4d_t *p4d);
 #else
 static inline int p4d_set_huge(p4d_t *p4d, phys_addr_t addr, pgprot_t prot)
 {
        return 0;
 }
-static inline int p4d_clear_huge(p4d_t *p4d)
-{
-       return 0;
-}
+static inline void p4d_clear_huge(p4d_t *p4d) { }
 #endif /* !__PAGETABLE_P4D_FOLDED */
 
 int pud_set_huge(pud_t *pud, phys_addr_t addr, pgprot_t prot);
@@ -1480,10 +1477,7 @@ static inline int pmd_set_huge(pmd_t *pmd, phys_addr_t addr, pgprot_t prot)
 {
        return 0;
 }
-static inline int p4d_clear_huge(p4d_t *p4d)
-{
-       return 0;
-}
+static inline void p4d_clear_huge(p4d_t *p4d) { }
 static inline int pud_clear_huge(pud_t *pud)
 {
        return 0;

diff --git a/mm/vmalloc.c b/mm/vmalloc.c
index c3af9b2..5b59cca 100644 (file)
--- a/mm/vmalloc.c
+++ b/mm/vmalloc.c
@@ -389,18 +389,15 @@ static void vunmap_p4d_range(pgd_t *pgd, unsigned long addr, unsigned long end,
 {
        p4d_t *p4d;
        unsigned long next;
-       int cleared;
 
        p4d = p4d_offset(pgd, addr);
        do {
                next = p4d_addr_end(addr, end);
 
-               cleared = p4d_clear_huge(p4d);
-               if (cleared || p4d_bad(*p4d))
+               p4d_clear_huge(p4d);
+               if (p4d_bad(*p4d))
                        *mask |= PGTBL_P4D_MODIFIED;
 
-               if (cleared)
-                       continue;
                if (p4d_none_or_clear_bad(p4d))
                        continue;
                vunmap_pud_range(p4d, addr, next, mask);