975b3d3d5b
Enable selection of different user/kernel VM splits for i386, including an optimized mode for 1GB physical RAM, which gives the kernel a direct (non HIGHMEM) mapping to the entire 1GB rather than just the first 896MB. There is a similarly a similarly optimized mode for machines with exactly 2GB of physical RAM. This can speed up the kernel by avoiding having to create/destroy temporary HIGHMEM mappings, and by not having to include HIGHMEM support at all on such machines. The flip side is that there's less virtual addressing left for userspace in these alternatives, and some binary-only kernel modules may misbehave unless rebuilt with the same VMSPLIT option as the main kernel image. Original idea/patch from Jens Axboe, modified based on suggestions from Linus et al. Signed-off-by: Mark Lord <mlord@pobox.com> Signed-off-by: Jens Axboe <axboe@suse.de> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org> |
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| .. | ||
| alpha | ||
| arm | ||
| arm26 | ||
| cris | ||
| frv | ||
| h8300 | ||
| i386 | ||
| ia64 | ||
| m32r | ||
| m68k | ||
| m68knommu | ||
| mips | ||
| parisc | ||
| powerpc | ||
| ppc | ||
| s390 | ||
| sh | ||
| sh64 | ||
| sparc | ||
| sparc64 | ||
| um | ||
| v850 | ||
| x86_64 | ||
| xtensa | ||