[PATCH] Reduce TLB flushing during process migration

[PATCH] Reduce TLB flushing during process migration

From: Martin Hicks <mort@wildopensource.com>

Another optimization patch from Jack Steiner, intended to reduce TLB
flushes during process migration.

Most architextures should define tlb_migrate_prepare() to be flush_tlb_mm(),
but on i386, it would be a wasted flush, because i386 disconnects previous
cpus from the tlb flush automatically.