speed process startup by 7%

[John Reiser]

Jakub Jelinek wrote:
> Prelink by default allocates libs on i?86 in the
> 0x00101000 .. 0x00e00000
> 0x02000000 .. 0x08000000
> 0x41000000 .. 0x50000000
> regions.  So, if kernel wants to put vDSO randomly into the ASCII zone,
> it can have 528 choices (2MB from 0xe00000 to 0x1010000) or if it doesn't
> care about that, it can use 18MB (0xe00000 to 0x2000000), i.e. 4608
> possibile placements.
> Of course it is possible to change prelink to pick up different
> ranges (though, the 0 .. 1MB+4KB range is not an option due to various
> emulators that need that range and from 0x08000000 or so start binaries
> and if possible, prelink would like to use at least part of the ASCII zone).

It would be nice if prelink default policy avoided 0 .. 0x111000
(1MB + 64KB + 4KB) so that vm86 could run various programs that
use "himem" where the segment base is 0xffff0 (1MB - 16)
and inclusive limit is 0xffff, which gives a highest address of
0x10ffef.  [It would have been nice if the default linux kernel
loaded at 0x110000 instead of 0x100000.  Then Win3.1 and linux
could have co-existed in memory.]

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