Module Name: src
Committed By: simonb
Date: Sun Aug 23 10:23:38 UTC 2020
Modified Files:
src/sys/arch/mips/include: mips_param.h proc.h
src/sys/arch/mips/mips: mipsX_subr.S vm_machdep.c
Log Message:
Use a 16kB USPACE (and larger kernel stack) for LP64 kernels. Invert
the logic for setting the USPACE size. Define a desired USPACE size
(16kB for LP64, 8kB otherwise) then divide by PAGE_SIZE to get UPAGES.
Fixes random segmap lossage, since the uarea usually sits immediately
above the segmap for a process. Thanks to mrg@, skrll@ and dholland@
for testing, debugging and general help tracking down this problem.
To generate a diff of this commit:
cvs rdiff -u -r1.45 -r1.46 src/sys/arch/mips/include/mips_param.h
cvs rdiff -u -r1.29 -r1.30 src/sys/arch/mips/include/proc.h
cvs rdiff -u -r1.108 -r1.109 src/sys/arch/mips/mips/mipsX_subr.S
cvs rdiff -u -r1.161 -r1.162 src/sys/arch/mips/mips/vm_machdep.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/sys/arch/mips/include/mips_param.h
diff -u src/sys/arch/mips/include/mips_param.h:1.45 src/sys/arch/mips/include/mips_param.h:1.46
--- src/sys/arch/mips/include/mips_param.h:1.45 Sun Jul 26 08:08:41 2020
+++ src/sys/arch/mips/include/mips_param.h Sun Aug 23 10:23:38 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: mips_param.h,v 1.45 2020/07/26 08:08:41 simonb Exp $ */
+/* $NetBSD: mips_param.h,v 1.46 2020/08/23 10:23:38 simonb Exp $ */
/*-
* Copyright (c) 2013 The NetBSD Foundation, Inc.
@@ -117,12 +117,18 @@
#endif
#define NSEGPG (1 << SEGLENGTH)
-#if PGSHIFT >= 13
-#define UPAGES 1 /* pages of u-area */
+#ifdef _LP64
+#define __MIN_USPACE 16384 /* LP64 needs a 16kB stack */
#else
-#define UPAGES 2 /* pages of u-area */
+/*
+ * Note for the non-LP64 case, cpu_switch_resume has the assumption
+ * that UPAGES == 2. For MIPS-I we wire USPACE in TLB #0 and #1.
+ * For MIPS3+ we wire USPACE in the the TLB #0 pair.
+ */
+#define __MIN_USPACE 8192 /* otherwise use an 8kB stack */
#endif
-#define USPACE (UPAGES*NBPG) /* size of u-area in bytes */
+#define USPACE MAX(__MIN_USPACE, PAGE_SIZE)
+#define UPAGES (USPACE / PAGE_SIZE) /* number of pages for u-area */
#define USPACE_ALIGN USPACE /* make sure it starts on a even VA */
/*
Index: src/sys/arch/mips/include/proc.h
diff -u src/sys/arch/mips/include/proc.h:1.29 src/sys/arch/mips/include/proc.h:1.30
--- src/sys/arch/mips/include/proc.h:1.29 Sun Jul 26 08:08:41 2020
+++ src/sys/arch/mips/include/proc.h Sun Aug 23 10:23:38 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: proc.h,v 1.29 2020/07/26 08:08:41 simonb Exp $ */
+/* $NetBSD: proc.h,v 1.30 2020/08/23 10:23:38 simonb Exp $ */
/*
* Copyright (c) 1992, 1993
@@ -52,7 +52,7 @@ struct mdlwp {
vaddr_t md_ss_addr; /* single step address for ptrace */
int md_ss_instr; /* single step instruction for ptrace */
volatile int md_astpending; /* AST pending on return to userland */
- int md_upte[2]; /* ptes for mapping u page */
+ int md_upte[UPAGES]; /* ptes for mapping u page */
};
struct mdproc {
Index: src/sys/arch/mips/mips/mipsX_subr.S
diff -u src/sys/arch/mips/mips/mipsX_subr.S:1.108 src/sys/arch/mips/mips/mipsX_subr.S:1.109
--- src/sys/arch/mips/mips/mipsX_subr.S:1.108 Sat Jun 13 12:53:42 2020
+++ src/sys/arch/mips/mips/mipsX_subr.S Sun Aug 23 10:23:38 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: mipsX_subr.S,v 1.108 2020/06/13 12:53:42 simonb Exp $ */
+/* $NetBSD: mipsX_subr.S,v 1.109 2020/08/23 10:23:38 simonb Exp $ */
/*
* Copyright 2002 Wasabi Systems, Inc.
@@ -2707,12 +2707,14 @@ END(MIPSX(lwp_trampoline))
* Disable the optimisation for PGSHIFT == 14 (aka ENABLE_MIPS_16KB_PAGE)
* as the code needs fixing for this case
*
- * _LP64 with UPAGES == 1 is always direct mappable; everything else can have
- * non-direct mappable USPACE.
+ * A TLB entry isn't used for the following cases:
+ * - 16kB USPACE
+ * - LP64 - USPACE is always accessed directly via XKPHYS
*/
LEAF_NOPROFILE(MIPSX(cpu_switch_resume))
-#if (PGSHIFT < 14)
+#if !defined(_LP64)
+#if (PAGE_SIZE < 16384)
#if (USPACE > PAGE_SIZE) || !defined(_LP64)
INT_L a1, L_MD_UPTE_0(a0) # a1 = upte[0]
#if (PGSHIFT & 1)
@@ -2789,7 +2791,8 @@ MIPSX(entry0set):
COP0_SYNC
MIPSX(resume):
#endif /* (USPACE > PAGE_SIZE) || !defined(_LP64) */
-#endif /* PGSHIFT < 14 */
+#endif /* PAGE_SIZE < 16384 */
+#endif /* ! LP64 */
#ifdef MIPSNNR2
PTR_L v0, L_PRIVATE(a0) # get lwp private
_MTC0 v0, MIPS_COP_0_USERLOCAL # make available for rdhwr
Index: src/sys/arch/mips/mips/vm_machdep.c
diff -u src/sys/arch/mips/mips/vm_machdep.c:1.161 src/sys/arch/mips/mips/vm_machdep.c:1.162
--- src/sys/arch/mips/mips/vm_machdep.c:1.161 Sun Aug 9 07:09:35 2020
+++ src/sys/arch/mips/mips/vm_machdep.c Sun Aug 23 10:23:38 2020
@@ -1,4 +1,4 @@
-/* $NetBSD: vm_machdep.c,v 1.161 2020/08/09 07:09:35 skrll Exp $ */
+/* $NetBSD: vm_machdep.c,v 1.162 2020/08/23 10:23:38 simonb Exp $ */
/*
* Copyright (c) 1988 University of Utah.
@@ -39,7 +39,7 @@
*/
#include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: vm_machdep.c,v 1.161 2020/08/09 07:09:35 skrll Exp $");
+__KERNEL_RCSID(0, "$NetBSD: vm_machdep.c,v 1.162 2020/08/23 10:23:38 simonb Exp $");
#include "opt_ddb.h"
#include "opt_cputype.h"
@@ -120,11 +120,6 @@ cpu_lwp_fork(struct lwp *l1, struct lwp
l2->l_md.md_upte[i] = 0;
}
if (!pmap_md_direct_mapped_vaddr_p(ua2)) {
- /*
- * UPAGES has to be 2 for 4KB PAGE_SIZE
- * UPAGES has to be 1 for >= 8KB PAGE_SIZE
- */
- CTASSERT((PGSHIFT == 12) == (UPAGES == 2));
pt_entry_t * const pte = pmap_pte_lookup(pmap_kernel(), ua2);
const uint32_t x = MIPS_HAS_R4K_MMU
? (MIPS3_PG_RO | MIPS3_PG_WIRED)
