Commit e75d07bd authored by Christophe Leroy's avatar Christophe Leroy Committed by Michael Ellerman
Browse files

powerpc: Remove find_current_mm_pte() 



Last usage of find_current_mm_pte() was removed by
commit 15759cb0 ("powerpc/perf/callchain: Use
__get_user_pages_fast in read_user_stack_slow")

Remove it.

Signed-off-by: default avatarChristophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: default avatarMichael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/ec79f462a3bfa8365b7df505e574d5d85246bc68.1646818177.git.christophe.leroy@csgroup.eu
parent 58369476

arch/powerpc/include/asm/pte-walk.h

+0 −25
Original line number Diff line number Diff line
@@ -60,29 +60,4 @@ static inline phys_addr_t ppc_find_vmap_phys(unsigned long addr) 
	return pa;

}



/*

 * This is what we should always use. Any other lockless page table lookup needs

 * careful audit against THP split.

 */

static inline pte_t *find_current_mm_pte(pgd_t *pgdir, unsigned long ea,

					 bool *is_thp, unsigned *hshift)

{

	pte_t *pte;



	VM_WARN(!arch_irqs_disabled(), "%s called with irq enabled\n", __func__);

	VM_WARN(pgdir != current->mm->pgd,

		"%s lock less page table lookup called on wrong mm\n", __func__);

	pte = __find_linux_pte(pgdir, ea, is_thp, hshift);



#if defined(CONFIG_DEBUG_VM) &&						\

	!(defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE))

	/*

	 * We should not find huge page if these configs are not enabled.

	 */

	if (hshift)

		WARN_ON(*hshift);

#endif

	return pte;

}



#endif /* _ASM_POWERPC_PTE_WALK_H */

arch/powerpc/mm/book3s64/pgtable.c

+2 −2
Original line number Diff line number Diff line
@@ -100,14 +100,14 @@ static void do_serialize(void *arg) 
}



/*

 * Serialize against find_current_mm_pte which does lock-less

 * Serialize against __find_linux_pte() which does lock-less

 * lookup in page tables with local interrupts disabled. For huge pages

 * it casts pmd_t to pte_t. Since format of pte_t is different from

 * pmd_t we want to prevent transit from pmd pointing to page table

 * to pmd pointing to huge page (and back) while interrupts are disabled.

 * We clear pmd to possibly replace it with page table pointer in

 * different code paths. So make sure we wait for the parallel

 * find_current_mm_pte to finish.

 * __find_linux_pte() to finish.

 */

void serialize_against_pte_lookup(struct mm_struct *mm)

{