Mon Jul 19 16:31:19 2021 UTC ()
Re-arrange the kernel pmap fast-path in pmap_extract() so that
when DEBUG is not enabled, the compiler can emit a tail-call to
vtophys_internal().


(thorpej)
diff -r1.298 -r1.299 src/sys/arch/alpha/alpha/pmap.c
cvs diff -r1.298 -r1.299 src/sys/arch/alpha/alpha/pmap.c (expand / switch to unified diff)

--- src/sys/arch/alpha/alpha/pmap.c 2021/07/16 19:02:22 1.298
+++ src/sys/arch/alpha/alpha/pmap.c 2021/07/19 16:31:19 1.299
@@ -1,14 +1,14 @@ @@ -1,14 +1,14 @@
1/* $NetBSD: pmap.c,v 1.298 2021/07/16 19:02:22 thorpej Exp $ */ 1/* $NetBSD: pmap.c,v 1.299 2021/07/19 16:31:19 thorpej Exp $ */
2 2
3/*- 3/*-
4 * Copyright (c) 1998, 1999, 2000, 2001, 2007, 2008, 2020 4 * Copyright (c) 1998, 1999, 2000, 2001, 2007, 2008, 2020
5 * The NetBSD Foundation, Inc. 5 * The NetBSD Foundation, Inc.
6 * All rights reserved. 6 * All rights reserved.
7 * 7 *
8 * This code is derived from software contributed to The NetBSD Foundation 8 * This code is derived from software contributed to The NetBSD Foundation
9 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility, 9 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
10 * NASA Ames Research Center, by Andrew Doran and Mindaugas Rasiukevicius, 10 * NASA Ames Research Center, by Andrew Doran and Mindaugas Rasiukevicius,
11 * and by Chris G. Demetriou. 11 * and by Chris G. Demetriou.
12 * 12 *
13 * Redistribution and use in source and binary forms, with or without 13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions 14 * modification, are permitted provided that the following conditions
@@ -125,27 +125,27 @@ @@ -125,27 +125,27 @@
125 * this module may delay invalidate or reduced protection 125 * this module may delay invalidate or reduced protection
126 * operations until such time as they are actually 126 * operations until such time as they are actually
127 * necessary. This module is given full information as 127 * necessary. This module is given full information as
128 * to which processors are currently using which maps, 128 * to which processors are currently using which maps,
129 * and to when physical maps must be made correct. 129 * and to when physical maps must be made correct.
130 */ 130 */
131 131
132#include "opt_lockdebug.h" 132#include "opt_lockdebug.h"
133#include "opt_sysv.h" 133#include "opt_sysv.h"
134#include "opt_multiprocessor.h" 134#include "opt_multiprocessor.h"
135 135
136#include <sys/cdefs.h> /* RCS ID & Copyright macro defns */ 136#include <sys/cdefs.h> /* RCS ID & Copyright macro defns */
137 137
138__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.298 2021/07/16 19:02:22 thorpej Exp $"); 138__KERNEL_RCSID(0, "$NetBSD: pmap.c,v 1.299 2021/07/19 16:31:19 thorpej Exp $");
139 139
140#include <sys/param.h> 140#include <sys/param.h>
141#include <sys/systm.h> 141#include <sys/systm.h>
142#include <sys/kernel.h> 142#include <sys/kernel.h>
143#include <sys/proc.h> 143#include <sys/proc.h>
144#include <sys/pool.h> 144#include <sys/pool.h>
145#include <sys/buf.h> 145#include <sys/buf.h>
146#include <sys/evcnt.h> 146#include <sys/evcnt.h>
147#include <sys/atomic.h> 147#include <sys/atomic.h>
148#include <sys/cpu.h> 148#include <sys/cpu.h>
149 149
150#include <uvm/uvm.h> 150#include <uvm/uvm.h>
151 151
@@ -2568,38 +2568,38 @@ pmap_extract(pmap_t pmap, vaddr_t va, pa @@ -2568,38 +2568,38 @@ pmap_extract(pmap_t pmap, vaddr_t va, pa
2568 pt_entry_t *l1pte, *l2pte, *l3pte; 2568 pt_entry_t *l1pte, *l2pte, *l3pte;
2569 paddr_t pa; 2569 paddr_t pa;
2570 2570
2571#ifdef DEBUG 2571#ifdef DEBUG
2572 if (pmapdebug & PDB_FOLLOW) 2572 if (pmapdebug & PDB_FOLLOW)
2573 printf("pmap_extract(%p, %lx) -> ", pmap, va); 2573 printf("pmap_extract(%p, %lx) -> ", pmap, va);
2574#endif 2574#endif
2575 2575
2576 /* 2576 /*
2577 * Take a faster path for the kernel pmap. Avoids locking, 2577 * Take a faster path for the kernel pmap. Avoids locking,
2578 * handles K0SEG. 2578 * handles K0SEG.
2579 */ 2579 */
2580 if (__predict_true(pmap == pmap_kernel())) { 2580 if (__predict_true(pmap == pmap_kernel())) {
2581 if (__predict_true(vtophys_internal(va, pap))) { 
2582#ifdef DEBUG 2581#ifdef DEBUG
2583 if (pmapdebug & PDB_FOLLOW) 2582 bool address_is_valid = vtophys_internal(va, pap);
 2583 if (pmapdebug & PDB_FOLLOW) {
 2584 if (address_is_valid) {
2584 printf("0x%lx (kernel vtophys)\n", *pap); 2585 printf("0x%lx (kernel vtophys)\n", *pap);
2585#endif 2586 } else {
2586 return true; 2587 printf("failed (kernel vtophys)\n");
 2588 }
2587 } 2589 }
2588#ifdef DEBUG 2590#else
2589 if (pmapdebug & PDB_FOLLOW) 2591 return vtophys_internal(va, pap);
2590 printf("failed (kernel vtophys)\n"); 
2591#endif 2592#endif
2592 return false; 
2593 } 2593 }
2594 2594
2595 pt_entry_t * const lev1map = pmap_lev1map(pmap); 2595 pt_entry_t * const lev1map = pmap_lev1map(pmap);
2596 2596
2597 PMAP_LOCK(pmap); 2597 PMAP_LOCK(pmap);
2598 2598
2599 l1pte = pmap_l1pte(lev1map, va); 2599 l1pte = pmap_l1pte(lev1map, va);
2600 if (pmap_pte_v(l1pte) == 0) 2600 if (pmap_pte_v(l1pte) == 0)
2601 goto out; 2601 goto out;
2602 2602
2603 l2pte = pmap_l2pte(lev1map, va, l1pte); 2603 l2pte = pmap_l2pte(lev1map, va, l1pte);
2604 if (pmap_pte_v(l2pte) == 0) 2604 if (pmap_pte_v(l2pte) == 0)
2605 goto out; 2605 goto out;