| Message ID | 20200121101728.14858-2-anju@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Superseded |
| Headers | show |
| Series | Re-enable IMC trace-mode | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (20862247a368dbb75d6e97d82345999adaacf3cc) |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 15 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
On 1/21/20 3:47 PM, Anju T Sudhakar wrote: > commit <249fad734a25> ""powerpc/perf: Disable trace_imc pmu" > disables IMC(In-Memory Collection) trace-mode in kernel, since frequent > mode switching between accumulation mode and trace mode via the spr LDBAR > in the hardware can trigger a checkstop(system crash). > > Patch to re-enable imc-trace mode in kernel. > > The following patch in this series will address the mode switching issue > by implementing a global lock, and will restrict the usage of > accumulation and trace-mode at a time. Reviewed-by: MAdhavan Srinivasan <maddy@linux.ibm.com> > > Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com> > --- > arch/powerpc/platforms/powernv/opal-imc.c | 9 +-------- > 1 file changed, 1 insertion(+), 8 deletions(-) > > diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c > index 000b350d4060..3b4518f4b643 100644 > --- a/arch/powerpc/platforms/powernv/opal-imc.c > +++ b/arch/powerpc/platforms/powernv/opal-imc.c > @@ -278,14 +278,7 @@ static int opal_imc_counters_probe(struct platform_device *pdev) > domain = IMC_DOMAIN_THREAD; > break; > case IMC_TYPE_TRACE: > - /* > - * FIXME. Using trace_imc events to monitor application > - * or KVM thread performance can cause a checkstop > - * (system crash). > - * Disable it for now. > - */ > - pr_info_once("IMC: disabling trace_imc PMU\n"); > - domain = -1; > + domain = IMC_DOMAIN_TRACE; > break; > default: > pr_warn("IMC Unknown Device type \n");
diff --git a/arch/powerpc/platforms/powernv/opal-imc.c b/arch/powerpc/platforms/powernv/opal-imc.c index 000b350d4060..3b4518f4b643 100644 --- a/arch/powerpc/platforms/powernv/opal-imc.c +++ b/arch/powerpc/platforms/powernv/opal-imc.c @@ -278,14 +278,7 @@ static int opal_imc_counters_probe(struct platform_device *pdev) domain = IMC_DOMAIN_THREAD; break; case IMC_TYPE_TRACE: - /* - * FIXME. Using trace_imc events to monitor application - * or KVM thread performance can cause a checkstop - * (system crash). - * Disable it for now. - */ - pr_info_once("IMC: disabling trace_imc PMU\n"); - domain = -1; + domain = IMC_DOMAIN_TRACE; break; default: pr_warn("IMC Unknown Device type \n");
commit <249fad734a25> ""powerpc/perf: Disable trace_imc pmu" disables IMC(In-Memory Collection) trace-mode in kernel, since frequent mode switching between accumulation mode and trace mode via the spr LDBAR in the hardware can trigger a checkstop(system crash). Patch to re-enable imc-trace mode in kernel. The following patch in this series will address the mode switching issue by implementing a global lock, and will restrict the usage of accumulation and trace-mode at a time. Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com> --- arch/powerpc/platforms/powernv/opal-imc.c | 9 +-------- 1 file changed, 1 insertion(+), 8 deletions(-)