diff options
| author | Nicholas Piggin <npiggin@gmail.com> | 2017-11-03 07:13:20 +0300 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2017-11-06 14:46:15 +0300 |
| commit | 9d2f510a66ec60411536b83dab831ee091c84307 (patch) | |
| tree | 0c121b6385a2309189bbe1edda5b28815f7f8952 /arch/powerpc/kernel/idle_book3s.S | |
| parent | b6b3755e9bec9c686a34ec81eacced0075370cbc (diff) | |
| download | linux-9d2f510a66ec60411536b83dab831ee091c84307.tar.xz | |
powerpc/64s/idle: avoid POWER9 DD1 and DD2.0 ERAT workaround on DD2.1
DD2.1 does not have to flush the ERAT after a state-loss idle.
Performance testing was done on a DD2.1 using only the stop0 idle state
(the shallowest state which supports state loss), using context_switch
selftest configured to ping-poing between two threads on the same core
and two different cores.
Performance improvement for same core is 7.0%, different cores is 14.8%.
Reviewed-by: Vaidyanathan Srinivasan <svaidy@linux.vnet.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Diffstat (limited to 'arch/powerpc/kernel/idle_book3s.S')
| -rw-r--r-- | arch/powerpc/kernel/idle_book3s.S | 2 |
1 files changed, 2 insertions, 0 deletions
diff --git a/arch/powerpc/kernel/idle_book3s.S b/arch/powerpc/kernel/idle_book3s.S index 175d49f468af..d77766814090 100644 --- a/arch/powerpc/kernel/idle_book3s.S +++ b/arch/powerpc/kernel/idle_book3s.S @@ -542,7 +542,9 @@ pnv_restore_hyp_resource_arch300: * then clear bit 60 in MMCRA to ensure the PMU starts running. */ blt cr3,1f +BEGIN_FTR_SECTION PPC_INVALIDATE_ERAT +END_FTR_SECTION_IFSET(CPU_FTR_POWER9_DD1 | CPU_FTR_POWER9_DD20) ld r1,PACAR1(r13) mfspr r4,SPRN_MMCRA ori r4,r4,(1 << (63-60)) |