powerpc/perf: Fix MMCR2 handling for EBB
In the recent commitb50a6c584b
"Clear MMCR2 when enabling PMU", I screwed up the handling of MMCR2 for tasks using EBB. We must make sure we set MMCR2 *before* ebb_switch_in(), otherwise we overwrite the value of MMCR2 that userspace may have written. That potentially breaks a task that uses EBB and manually uses MMCR2 for event freezing. Fixes:b50a6c584b
("powerpc/perf: Clear MMCR2 when enabling PMU") Cc: stable@vger.kernel.org Signed-off-by: Michael Ellerman <mpe@ellerman.id.au> Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
This commit is contained in:
Родитель
6f5405bc2e
Коммит
8903461c9b
|
@ -1307,6 +1307,9 @@ static void power_pmu_enable(struct pmu *pmu)
|
||||||
out_enable:
|
out_enable:
|
||||||
pmao_restore_workaround(ebb);
|
pmao_restore_workaround(ebb);
|
||||||
|
|
||||||
|
if (ppmu->flags & PPMU_ARCH_207S)
|
||||||
|
mtspr(SPRN_MMCR2, 0);
|
||||||
|
|
||||||
mmcr0 = ebb_switch_in(ebb, cpuhw->mmcr[0]);
|
mmcr0 = ebb_switch_in(ebb, cpuhw->mmcr[0]);
|
||||||
|
|
||||||
mb();
|
mb();
|
||||||
|
@ -1315,9 +1318,6 @@ static void power_pmu_enable(struct pmu *pmu)
|
||||||
|
|
||||||
write_mmcr0(cpuhw, mmcr0);
|
write_mmcr0(cpuhw, mmcr0);
|
||||||
|
|
||||||
if (ppmu->flags & PPMU_ARCH_207S)
|
|
||||||
mtspr(SPRN_MMCR2, 0);
|
|
||||||
|
|
||||||
/*
|
/*
|
||||||
* Enable instruction sampling if necessary
|
* Enable instruction sampling if necessary
|
||||||
*/
|
*/
|
||||||
|
|
Загрузка…
Ссылка в новой задаче