• LEROY Christophe's avatar
    powerpc/8xx: reduce pressure on TLB due to context switches · debddd95
    LEROY Christophe authored
    For nohash powerpc, when we run out of contexts, contexts are freed by stealing
    used contexts in-turn. When a victim has been selected, the associated TLB
    entries are freed using _tlbil_pid(). Unfortunatly, on the PPC 8xx, _tlbil_pid()
    does a tlbia, hence flushes ALL TLB entries and not only the one linked to the
    stolen context. Therefore, as implented today, at each task switch requiring a
    new context, all entries are flushed.
    
    This patch modifies the implementation so that when running out of contexts, all
    contexts get freed at once, hence dividing the number of calls to tlbia by 16.
    Signed-off-by: default avatarChristophe Leroy <christophe.leroy@c-s.fr>
    Signed-off-by: default avatarScott Wood <scottwood@freescale.com>
    debddd95
mmu_context_nohash.c 13.2 KB