diff options
author | Cliff Wickman <cpw@sgi.com> | 2010-09-08 10:14:27 -0500 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@suse.de> | 2010-11-22 11:03:05 -0800 |
commit | b6af39cd87b99525e0e6838bdee5819104cc1182 (patch) | |
tree | f585b89c50b1f8f15dceafe2a454a10de84c53ca | |
parent | bbfc3a3c96fca7386244f1c0ddf88c8a958f044d (diff) |
x86, kdump: Change copy_oldmem_page() to use cached addressing
commit 37a2f9f30a360fb03522d15c85c78265ccd80287 upstream.
The copy of /proc/vmcore to a user buffer proceeds much faster
if the kernel addresses memory as cached.
With this patch we have seen an increase in transfer rate from
less than 15MB/s to 80-460MB/s, depending on size of the
transfer. This makes a big difference in time needed to save a
system dump.
Signed-off-by: Cliff Wickman <cpw@sgi.com>
Acked-by: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: kexec@lists.infradead.org
LKML-Reference: <E1OtMLz-0001yp-Ia@eag09.americas.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
-rw-r--r-- | arch/x86/kernel/crash_dump_64.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/arch/x86/kernel/crash_dump_64.c b/arch/x86/kernel/crash_dump_64.c index ce96a6b575b..994828899e0 100644 --- a/arch/x86/kernel/crash_dump_64.c +++ b/arch/x86/kernel/crash_dump_64.c @@ -34,7 +34,7 @@ ssize_t copy_oldmem_page(unsigned long pfn, char *buf, if (!csize) return 0; - vaddr = ioremap(pfn << PAGE_SHIFT, PAGE_SIZE); + vaddr = ioremap_cache(pfn << PAGE_SHIFT, PAGE_SIZE); if (!vaddr) return -ENOMEM; |