diff options
| author | Cliff Wickman <cpw@sgi.com> | 2010-09-08 10:14:27 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-09-09 09:46:23 +0200 |
| commit | 37a2f9f30a360fb03522d15c85c78265ccd80287 (patch) | |
| tree | bcc77b64a38aff205daacea238cf0586e8301c68 | |
| parent | 1c5f50ee347daea013671f718b70cd6bf497bef9 (diff) | |
x86, kdump: Change copy_oldmem_page() to use cached addressing
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
Cc: <stable@kernel.org> # as far back as it would apply
LKML-Reference: <E1OtMLz-0001yp-Ia@eag09.americas.sgi.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -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 045b36cada6..bf43188ca65 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; |