From: William Lee Irwin III <wli@holomorphy.com>
To: Andrew Morton <akpm@digeo.com>
Cc: lkml <linux-kernel@vger.kernel.org>, linux-mm@kvack.org
Subject: Re: 2.5.53-mm2
Date: Wed, 1 Jan 2003 20:53:27 -0800 [thread overview]
Message-ID: <20030102045327.GC7644@holomorphy.com> (raw)
In-Reply-To: <3E0E4744.8EE126ED@digeo.com>
On Sat, Dec 28, 2002 at 04:52:20PM -0800, Andrew Morton wrote:
> wli-11_pgd_ctor.patch
> (undescribed patch)
A moment's reflection on the subject suggests to me it's worthwhile to
generalize pgd_ctor support so it works (without #ifdefs!) on both PAE
and non-PAE. This tiny tweak is actually more noticeably beneficial
on non-PAE systems but only really because pgd_alloc() is more visible;
the most likely reason it's less visible on PAE is "other overhead".
It looks particularly nice since it removes more code than it adds.
Touch tested on NUMA-Q (PAE). OFTC #kn testers testing the non-PAE case.
arch/i386/mm/init.c | 36 +++++++++++++----------
arch/i386/mm/pgtable.c | 58 ++++++++++++--------------------------
include/asm-i386/pgtable-3level.h | 2 -
include/asm-i386/pgtable.h | 13 +-------
4 files changed, 41 insertions(+), 68 deletions(-)
diff -urpN mm3-2.5.53-1/arch/i386/mm/init.c mm3-2.5.53-2/arch/i386/mm/init.c
--- mm3-2.5.53-1/arch/i386/mm/init.c 2003-01-01 18:49:19.000000000 -0800
+++ mm3-2.5.53-2/arch/i386/mm/init.c 2003-01-01 18:51:17.000000000 -0800
@@ -504,32 +504,36 @@ void __init mem_init(void)
#endif
}
-#if CONFIG_X86_PAE
#include <linux/slab.h>
-kmem_cache_t *pae_pmd_cachep;
-kmem_cache_t *pae_pgd_cachep;
+kmem_cache_t *pmd_cache;
+kmem_cache_t *pgd_cache;
-void pae_pmd_ctor(void *, kmem_cache_t *, unsigned long);
-void pae_pgd_ctor(void *, kmem_cache_t *, unsigned long);
+void pmd_ctor(void *, kmem_cache_t *, unsigned long);
+void pgd_ctor(void *, kmem_cache_t *, unsigned long);
void __init pgtable_cache_init(void)
{
+ if (PTRS_PER_PMD > 1) {
+ pmd_cache = kmem_cache_create("pae_pmd",
+ PTRS_PER_PMD*sizeof(pmd_t),
+ 0,
+ SLAB_HWCACHE_ALIGN | SLAB_MUST_HWCACHE_ALIGN,
+ pmd_ctor,
+ NULL);
+
+ if (!pmd_cache)
+ panic("pgtable_cache_init(): cannot create pmd cache");
+ }
+
/*
* PAE pgds must be 16-byte aligned:
*/
- pae_pmd_cachep = kmem_cache_create("pae_pmd", 4096, 0,
- SLAB_HWCACHE_ALIGN | SLAB_MUST_HWCACHE_ALIGN, pae_pmd_ctor, NULL);
-
- if (!pae_pmd_cachep)
- panic("init_pae(): cannot allocate pae_pmd SLAB cache");
-
- pae_pgd_cachep = kmem_cache_create("pae_pgd", 32, 0,
- SLAB_HWCACHE_ALIGN | SLAB_MUST_HWCACHE_ALIGN, pae_pgd_ctor, NULL);
- if (!pae_pgd_cachep)
- panic("init_pae(): Cannot alloc pae_pgd SLAB cache");
+ pgd_cache = kmem_cache_create("pgd", PTRS_PER_PGD*sizeof(pgd_t), 0,
+ SLAB_HWCACHE_ALIGN | SLAB_MUST_HWCACHE_ALIGN, pgd_ctor, NULL);
+ if (!pgd_cache)
+ panic("pgtable_cache_init(): Cannot create pgd cache");
}
-#endif
/* Put this after the callers, so that it cannot be inlined */
static int do_test_wp_bit(void)
diff -urpN mm3-2.5.53-1/arch/i386/mm/pgtable.c mm3-2.5.53-2/arch/i386/mm/pgtable.c
--- mm3-2.5.53-1/arch/i386/mm/pgtable.c 2003-01-01 18:49:19.000000000 -0800
+++ mm3-2.5.53-2/arch/i386/mm/pgtable.c 2003-01-01 18:51:17.000000000 -0800
@@ -166,19 +166,20 @@ struct page *pte_alloc_one(struct mm_str
return pte;
}
-#if CONFIG_X86_PAE
+extern kmem_cache_t *pmd_cache;
+extern kmem_cache_t *pgd_cache;
-extern kmem_cache_t *pae_pmd_cachep;
-
-void pae_pmd_ctor(void *__pmd, kmem_cache_t *pmd_cache, unsigned long flags)
+void pmd_ctor(void *__pmd, kmem_cache_t *pmd_cache, unsigned long flags)
{
clear_page(__pmd);
}
-void pae_pgd_ctor(void *__pgd, kmem_cache_t *pgd_cache, unsigned long flags)
+void pgd_ctor(void *__pgd, kmem_cache_t *pgd_cache, unsigned long flags)
{
pgd_t *pgd = __pgd;
+ if (PTRS_PER_PMD == 1)
+ memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
memcpy(pgd + USER_PTRS_PER_PGD,
swapper_pg_dir + USER_PTRS_PER_PGD,
(PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
@@ -187,59 +188,38 @@ void pae_pgd_ctor(void *__pgd, kmem_cach
pgd_t *pgd_alloc(struct mm_struct *mm)
{
int i;
- pgd_t *pgd = kmem_cache_alloc(pae_pgd_cachep, SLAB_KERNEL);
+ pgd_t *pgd = kmem_cache_alloc(pgd_cache, SLAB_KERNEL);
- if (!pgd)
+ if (PTRS_PER_PMD == 1)
+ return pgd;
+ else if (!pgd)
return NULL;
for (i = 0; i < USER_PTRS_PER_PGD; ++i) {
- pmd_t *pmd = kmem_cache_alloc(pae_pmd_cachep, SLAB_KERNEL);
+ pmd_t *pmd = kmem_cache_alloc(pmd_cache, SLAB_KERNEL);
if (!pmd)
goto out_oom;
- else if ((unsigned long)pmd & ~PAGE_MASK) {
- printk("kmem_cache_alloc did wrong! death ensues!\n");
- goto out_oom;
- }
set_pgd(pgd + i, __pgd(1 + __pa((unsigned long long)((unsigned long)pmd))));
}
return pgd;
out_oom:
for (i--; i >= 0; --i)
- kmem_cache_free(pae_pmd_cachep, (void *)__va(pgd_val(pgd[i])-1));
- kmem_cache_free(pae_pgd_cachep, (void *)pgd);
+ kmem_cache_free(pmd_cache, (void *)__va(pgd_val(pgd[i])-1));
+ kmem_cache_free(pgd_cache, (void *)pgd);
return NULL;
}
void pgd_free(pgd_t *pgd)
{
int i;
- for (i = 0; i < USER_PTRS_PER_PGD; ++i) {
- kmem_cache_free(pae_pmd_cachep, (void *)__va(pgd_val(pgd[i])-1));
- set_pgd(pgd + i, __pgd(0));
- }
- kmem_cache_free(pae_pgd_cachep, (void *)pgd);
-}
-
-#else
-pgd_t *pgd_alloc(struct mm_struct *mm)
-{
- pgd_t *pgd = (pgd_t *)__get_free_page(GFP_KERNEL);
-
- if (pgd) {
- memset(pgd, 0, USER_PTRS_PER_PGD * sizeof(pgd_t));
- memcpy(pgd + USER_PTRS_PER_PGD,
- swapper_pg_dir + USER_PTRS_PER_PGD,
- (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+ if (PTRS_PER_PMD > 1) {
+ for (i = 0; i < USER_PTRS_PER_PGD; ++i) {
+ kmem_cache_free(pmd_cache, (void *)__va(pgd_val(pgd[i])-1));
+ set_pgd(pgd + i, __pgd(0));
+ }
}
- return pgd;
-}
-void pgd_free(pgd_t *pgd)
-{
- free_page((unsigned long)pgd);
+ kmem_cache_free(pgd_cache, (void *)pgd);
}
-
-#endif /* CONFIG_X86_PAE */
-
diff -urpN mm3-2.5.53-1/include/asm-i386/pgtable-3level.h mm3-2.5.53-2/include/asm-i386/pgtable-3level.h
--- mm3-2.5.53-1/include/asm-i386/pgtable-3level.h 2002-12-23 21:21:07.000000000 -0800
+++ mm3-2.5.53-2/include/asm-i386/pgtable-3level.h 2003-01-01 18:51:17.000000000 -0800
@@ -106,6 +106,4 @@ static inline pmd_t pfn_pmd(unsigned lon
return __pmd(((unsigned long long)page_nr << PAGE_SHIFT) | pgprot_val(pgprot));
}
-extern struct kmem_cache_s *pae_pgd_cachep;
-
#endif /* _I386_PGTABLE_3LEVEL_H */
diff -urpN mm3-2.5.53-1/include/asm-i386/pgtable.h mm3-2.5.53-2/include/asm-i386/pgtable.h
--- mm3-2.5.53-1/include/asm-i386/pgtable.h 2003-01-01 18:49:21.000000000 -0800
+++ mm3-2.5.53-2/include/asm-i386/pgtable.h 2003-01-01 18:51:17.000000000 -0800
@@ -41,22 +41,13 @@ extern unsigned long empty_zero_page[102
#ifndef __ASSEMBLY__
#if CONFIG_X86_PAE
# include <asm/pgtable-3level.h>
-
-/*
- * Need to initialise the X86 PAE caches
- */
-extern void pgtable_cache_init(void);
-
#else
# include <asm/pgtable-2level.h>
+#endif
-/*
- * No page table caches to initialise
- */
-#define pgtable_cache_init() do { } while (0)
+void pgtable_cache_init(void);
#endif
-#endif
#define __beep() asm("movb $0x3,%al; outb %al,$0x61")
--
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next prev parent reply other threads:[~2003-01-02 4:53 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2002-12-29 0:52 2.5.53-mm2 Andrew Morton
2003-01-02 4:53 ` William Lee Irwin III [this message]
2003-01-02 5:25 ` 2.5.53-mm2 William Lee Irwin III
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