Re: [PATCH] powerpc/8xx: reduce pressure on TLB due to context switches

2015-01-06 Thread Scott Wood
On Mon, 2015-01-05 at 16:14 +0100, Christophe Leroy wrote: > + } > + __clear_bit(id, stale_map[cpu]); > + > + } Whitespace > + > + /* Flush the TLB for all contexts */ > + _tlbil_all(); Can you put a comment in here pointing out that for this to work on SMP, i

[PATCH] powerpc/8xx: reduce pressure on TLB due to context switches

2015-01-05 Thread Christophe Leroy
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 on

[PATCH] powerpc/8xx: reduce pressure on TLB due to context switches

2015-01-05 Thread Christophe Leroy
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 on