From a6d27ea01a702b51b9dc102aebcae39151bea8e3 Mon Sep 17 00:00:00 2001 From: Claudio Imbrenda Date: Tue, 5 Dec 2023 18:32:52 +0100 Subject: s390/mm: convert pgste locking functions to C Convert pgste_get_lock() and pgste_set_unlock() to C. There is no real reasons to keep them in assembler. Having them in C makes them more readable and maintainable, and better instructions are used automatically when available. Signed-off-by: Claudio Imbrenda Acked-by: Alexander Gordeev Reviewed-by: Heiko Carstens Link: https://lore.kernel.org/r/20231205173252.62305-1-imbrenda@linux.ibm.com Signed-off-by: Alexander Gordeev --- arch/s390/mm/pgtable.c | 29 ++++++++++------------------- 1 file changed, 10 insertions(+), 19 deletions(-) diff --git a/arch/s390/mm/pgtable.c b/arch/s390/mm/pgtable.c index 3bd2ab2a9a34..6c4523aa4fdf 100644 --- a/arch/s390/mm/pgtable.c +++ b/arch/s390/mm/pgtable.c @@ -125,32 +125,23 @@ static inline pte_t ptep_flush_lazy(struct mm_struct *mm, static inline pgste_t pgste_get_lock(pte_t *ptep) { - unsigned long new = 0; + unsigned long value = 0; #ifdef CONFIG_PGSTE - unsigned long old; - - asm( - " lg %0,%2\n" - "0: lgr %1,%0\n" - " nihh %0,0xff7f\n" /* clear PCL bit in old */ - " oihh %1,0x0080\n" /* set PCL bit in new */ - " csg %0,%1,%2\n" - " jl 0b\n" - : "=&d" (old), "=&d" (new), "=Q" (ptep[PTRS_PER_PTE]) - : "Q" (ptep[PTRS_PER_PTE]) : "cc", "memory"); + unsigned long *ptr = (unsigned long *)(ptep + PTRS_PER_PTE); + + do { + value = __atomic64_or_barrier(PGSTE_PCL_BIT, ptr); + } while (value & PGSTE_PCL_BIT); + value |= PGSTE_PCL_BIT; #endif - return __pgste(new); + return __pgste(value); } static inline void pgste_set_unlock(pte_t *ptep, pgste_t pgste) { #ifdef CONFIG_PGSTE - asm( - " nihh %1,0xff7f\n" /* clear PCL bit */ - " stg %1,%0\n" - : "=Q" (ptep[PTRS_PER_PTE]) - : "d" (pgste_val(pgste)), "Q" (ptep[PTRS_PER_PTE]) - : "cc", "memory"); + barrier(); + WRITE_ONCE(*(unsigned long *)(ptep + PTRS_PER_PTE), pgste_val(pgste) & ~PGSTE_PCL_BIT); #endif } -- cgit