Commit-ID: 37a2f9f30a360fb03522d15c85c78265ccd80287 Gitweb: http://git.kernel.org/tip/37a2f9f30a360fb03522d15c85c78265ccd80287 Author: Cliff Wickman <cpw@xxxxxxx> AuthorDate: Wed, 8 Sep 2010 10:14:27 -0500 Committer: Ingo Molnar <mingo@xxxxxxx> CommitDate: Thu, 9 Sep 2010 09:46:23 +0200 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@xxxxxxx> Acked-by: "Eric W. Biederman" <ebiederm@xxxxxxxxxxxx> Cc: kexec@xxxxxxxxxxxxxxxxxxx Cc: <stable@xxxxxxxxxx> # as far back as it would apply LKML-Reference: <E1OtMLz-0001yp-Ia@xxxxxxxxxxxxxxxxxxxxxx> Signed-off-by: Ingo Molnar <mingo@xxxxxxx> --- 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 045b36c..bf43188 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; -- To unsubscribe from this list: send the line "unsubscribe linux-tip-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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