[tip:x86/cleanups] x86, cleanups: Use clear_page/copy_page rather than memset/memcpy

tip-bot for Jan Beulich
2010-09-22T23:58:24Z

Commit-ID: 234bb549eea16ec7d5207ba747fb8dbf489e64c1
Gitweb: http://git.kernel.org/tip/234bb549eea16ec7d5207ba747fb8dbf489e64c1
Author: Jan Beulich <JBeulich@novell.com>
AuthorDate: Thu, 2 Sep 2010 13:46:34 +0100
Committer: H. Peter Anvin <hpa@linux.intel.com>
CommitDate: Wed, 22 Sep 2010 15:36:49 -0700

x86, cleanups: Use clear_page/copy_page rather than memset/memcpy

When operating on whole pages, use clear_page() and copy_page() in
favor of memset() and memcpy(); after all that's what they are
intended for.

Signed-off-by: Jan Beulich <jbeulich@novell.com>
LKML-Reference: <4C7FB8CA0200007800013F51@vpn.id2.novell.com>
Cc: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
---
arch/x86/kernel/machine_kexec_64.c | 4 ++--
arch/x86/kvm/lapic.c | 3 +--
arch/x86/mm/init_32.c | 4 ++--
arch/x86/mm/init_64.c | 2 +-
4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/arch/x86/kernel/machine_kexec_64.c b/arch/x86/kernel/machine_kexec_64.c
index 035c8c5..b3ea9db 100644
--- a/arch/x86/kernel/machine_kexec_64.c
+++ b/arch/x86/kernel/machine_kexec_64.c
@@ -36,7 +36,7 @@ static int init_one_level2_page(struct kimage *image, pgd_t *pgd,
if (!page)
goto out;
pud = (pud_t *)page_address(page);
- memset(pud, 0, PAGE_SIZE);
+ clear_page(pud);
set_pgd(pgd, __pgd(__pa(pud) | _KERNPG_TABLE));
}
pud = pud_offset(pgd, addr);
@@ -45,7 +45,7 @@ static int init_one_level2_page(struct kimage *image, pgd_t *pgd,
if (!page)
goto out;
pmd = (pmd_t *)page_address(page);
- memset(pmd, 0, PAGE_SIZE);
+ clear_page(pmd);
set_pud(pud, __pud(__pa(pmd) | _KERNPG_TABLE));
}
pmd = pmd_offset(pud, addr);
diff --git a/arch/x86/kvm/lapic.c b/arch/x86/kvm/lapic.c
index 77d8c0f..22b06f7 100644
--- a/arch/x86/kvm/lapic.c
+++ b/arch/x86/kvm/lapic.c
@@ -1056,14 +1056,13 @@ int kvm_create_lapic(struct kvm_vcpu *vcpu)

vcpu->arch.apic = apic;

- apic->regs_page = alloc_page(GFP_KERNEL);
+ apic->regs_page = alloc_page(GFP_KERNEL|__GFP_ZERO);
if (apic->regs_page == NULL) {
printk(KERN_ERR "malloc apic regs error for vcpu %x\n",
vcpu->vcpu_id);
goto nomem_free_apic;
}
apic->regs = page_address(apic->regs_page);
- memset(apic->regs, 0, PAGE_SIZE);
apic->vcpu = vcpu;

hrtimer_init(&apic->lapic_timer.timer, CLOCK_MONOTONIC,
diff --git a/arch/x86/mm/init_32.c b/arch/x86/mm/init_32.c
index bca7909..558f2d3 100644
--- a/arch/x86/mm/init_32.c
+++ b/arch/x86/mm/init_32.c
@@ -67,7 +67,7 @@ static __init void *alloc_low_page(void)
panic("alloc_low_page: ran out of memory");

adr = __va(pfn * PAGE_SIZE);
- memset(adr, 0, PAGE_SIZE);
+ clear_page(adr);
return adr;
}

@@ -558,7 +558,7 @@ char swsusp_pg_dir[PAGE_SIZE]

static inline void save_pg_dir(void)
{
- memcpy(swsusp_pg_dir, swapper_pg_dir, PAGE_SIZE);
+ copy_page(swsusp_pg_dir, swapper_pg_dir);
}
#else /* !CONFIG_ACPI_SLEEP */
static inline void save_pg_dir(void)
diff --git a/arch/x86/mm/init_64.c b/arch/x86/mm/init_64.c
index 9a66746..7c48ad4 100644
--- a/arch/x86/mm/init_64.c
+++ b/arch/x86/mm/init_64.c
@@ -293,7 +293,7 @@ static __ref void *alloc_low_page(unsigned long *phys)
panic("alloc_low_page: ran out of memory");

adr = early_memremap(pfn * PAGE_SIZE, PAGE_SIZE);
- memset(adr, 0, PAGE_SIZE);
+ clear_page(adr);
*phys = pfn * PAGE_SIZE;
return adr;
}