Re: [parisc-linux] 2.4.0-test6 lack of speed

[Richard Hirst <rhirst@linuxcare.com>]

On Tue, Aug 22, 2000 at 03:52:21PM +0100, Richard Hirst wrote:
> > __flush_dcache_range: addr 0x00001000, size 770048
> > __flush_icache_range: addr 0x00001000, size 770048
> > __flush_dcache_range: addr 0x000bd000, size 24576
> > __flush_icache_range: addr 0x000bd000, size 24576
> > __flush_dcache_range: addr 0x000c3000, size 102400
> > __flush_icache_range: addr 0x000c3000, size 102400
> > __flush_dcache_range: addr 0x2001f000, size 268308480
> > __flush_icache_range: addr 0x2001f000, size 268308480

Those ones are caused by a call to flush_page_range() being added to
mm/mmap.c:exit_mmap().

We just blindly assume addresses passed to flush_page_range() are
kernel virtual addresses, but in this case I guess they are user
process virtual addresses.  Even so, the last one below looks
like a rather large area to have mmapped.

exit_mmap: calling flush_cache_range(0x00001000, 0x00083000)
exit_mmap: calling flush_cache_range(0x00083000, 0x00085000)
exit_mmap: calling flush_cache_range(0x00085000, 0x00088000)
exit_mmap: calling flush_cache_range(0x2001f000, 0x30000000)

(the exit_mmap debug is from a different kernel build, so don't
try and match the numbers with those quoted above)

Richard