linux/include/asm-generic/pgtable-nopud.h
Vineet Gupta b08861d10b asm-generic/tlb: stub out pud_free_tlb() if nopud ...
... independent of __ARCH_HAS_4LEVEL_HACK

This came up when removing __ARCH_HAS_5LEVEL_HACK for ARC as code bloat.
With this patch we see the following code reduction

| bloat-o-meter2 vmlinux-B-elide-ARCH_USE_5LEVEL_HACK vmlinux-C-elide-pud_free_tlb
| add/remove: 0/0 grow/shrink: 0/1 up/down: 0/-104 (-104)
| function                                     old     new   delta
| free_pgd_range                               656     552    -104
| Total: Before=4137276, After=4137172, chg -1.000000%

Note: The primary change is alternate defintion for pud_free_tlb() but
while there also removed empty stubs for __pud_free_tlb, which is anyhow
called only from pud_free_tlb()

Link: http://lkml.kernel.org/r/20191016162400.14796-3-vgupta@synopsys.com
Signed-off-by: Vineet Gupta <vgupta@synopsys.com>
Acked-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Acked-by: Linus Torvalds <torvalds@linux-foundation.org>
Cc: "Aneesh Kumar K . V" <aneesh.kumar@linux.ibm.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Nick Piggin <npiggin@gmail.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2019-12-01 06:29:19 -08:00

70 lines
2.0 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
#ifndef _PGTABLE_NOPUD_H
#define _PGTABLE_NOPUD_H
#ifndef __ASSEMBLY__
#ifdef __ARCH_USE_5LEVEL_HACK
#include <asm-generic/pgtable-nop4d-hack.h>
#else
#include <asm-generic/pgtable-nop4d.h>
#define __PAGETABLE_PUD_FOLDED 1
/*
* Having the pud type consist of a p4d gets the size right, and allows
* us to conceptually access the p4d entry that this pud is folded into
* without casting.
*/
typedef struct { p4d_t p4d; } pud_t;
#define PUD_SHIFT P4D_SHIFT
#define PTRS_PER_PUD 1
#define PUD_SIZE (1UL << PUD_SHIFT)
#define PUD_MASK (~(PUD_SIZE-1))
/*
* The "p4d_xxx()" functions here are trivial for a folded two-level
* setup: the pud is never bad, and a pud always exists (as it's folded
* into the p4d entry)
*/
static inline int p4d_none(p4d_t p4d) { return 0; }
static inline int p4d_bad(p4d_t p4d) { return 0; }
static inline int p4d_present(p4d_t p4d) { return 1; }
static inline void p4d_clear(p4d_t *p4d) { }
#define pud_ERROR(pud) (p4d_ERROR((pud).p4d))
#define p4d_populate(mm, p4d, pud) do { } while (0)
#define p4d_populate_safe(mm, p4d, pud) do { } while (0)
/*
* (puds are folded into p4ds so this doesn't get actually called,
* but the define is needed for a generic inline function.)
*/
#define set_p4d(p4dptr, p4dval) set_pud((pud_t *)(p4dptr), (pud_t) { p4dval })
static inline pud_t *pud_offset(p4d_t *p4d, unsigned long address)
{
return (pud_t *)p4d;
}
#define pud_val(x) (p4d_val((x).p4d))
#define __pud(x) ((pud_t) { __p4d(x) })
#define p4d_page(p4d) (pud_page((pud_t){ p4d }))
#define p4d_page_vaddr(p4d) (pud_page_vaddr((pud_t){ p4d }))
/*
* allocating and freeing a pud is trivial: the 1-entry pud is
* inside the p4d, so has no extra memory associated with it.
*/
#define pud_alloc_one(mm, address) NULL
#define pud_free(mm, x) do { } while (0)
#define pud_free_tlb(tlb, x, a) do { } while (0)
#undef pud_addr_end
#define pud_addr_end(addr, end) (end)
#endif /* __ASSEMBLY__ */
#endif /* !__ARCH_USE_5LEVEL_HACK */
#endif /* _PGTABLE_NOPUD_H */