| Message ID | 1510232445-10869-1-git-send-email-anju@linux.vnet.ibm.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Headers | show |
| Series | [v3] powerpc/kernel/sysfs: Export ldbar spr to sysfs | expand |
Anju T Sudhakar <anju@linux.vnet.ibm.com> writes: > diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c > index 4437c70..caefb64 100644 > --- a/arch/powerpc/kernel/sysfs.c > +++ b/arch/powerpc/kernel/sysfs.c > @@ -757,6 +759,9 @@ static int register_cpu_online(unsigned int cpu) > device_create_file(s, &pmc_attrs[i]); > > #ifdef CONFIG_PPC64 > + if (cpu_has_feature(CPU_FTR_ARCH_300)) > + device_create_file(s, &dev_attr_ldbar); Is this register readable in supervisor state? cheers
Hi, On Tuesday 06 March 2018 04:35 PM, Michael Ellerman wrote: > Anju T Sudhakar <anju@linux.vnet.ibm.com> writes: > >> diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c >> index 4437c70..caefb64 100644 >> --- a/arch/powerpc/kernel/sysfs.c >> +++ b/arch/powerpc/kernel/sysfs.c >> @@ -757,6 +759,9 @@ static int register_cpu_online(unsigned int cpu) >> device_create_file(s, &pmc_attrs[i]); >> >> #ifdef CONFIG_PPC64 >> + if (cpu_has_feature(CPU_FTR_ARCH_300)) >> + device_create_file(s, &dev_attr_ldbar); > Is this register readable in supervisor state? This is a nice catch, thanks. :) The guest kernel can not access the register, it is only readable in the hypervisor state. I will resend the patch with a condition check so that this spr will not get registered for guest kernel. Regards, Anju > > cheers >
diff --git a/arch/powerpc/kernel/sysfs.c b/arch/powerpc/kernel/sysfs.c index 4437c70..caefb64 100644 --- a/arch/powerpc/kernel/sysfs.c +++ b/arch/powerpc/kernel/sysfs.c @@ -485,6 +485,7 @@ SYSFS_PMCSETUP(mmcra, SPRN_MMCRA); SYSFS_SPRSETUP(purr, SPRN_PURR); SYSFS_SPRSETUP(spurr, SPRN_SPURR); SYSFS_SPRSETUP(pir, SPRN_PIR); +SYSFS_SPRSETUP(ldbar, SPRN_LDBAR); /* Lets only enable read for phyp resources and @@ -492,6 +493,7 @@ SYSFS_SPRSETUP(pir, SPRN_PIR); Lets be conservative and default to pseries. */ static DEVICE_ATTR(mmcra, 0600, show_mmcra, store_mmcra); +static DEVICE_ATTR(ldbar, 0400, show_ldbar, NULL); static DEVICE_ATTR(spurr, 0400, show_spurr, NULL); static DEVICE_ATTR(purr, 0400, show_purr, store_purr); static DEVICE_ATTR(pir, 0400, show_pir, NULL); @@ -757,6 +759,9 @@ static int register_cpu_online(unsigned int cpu) device_create_file(s, &pmc_attrs[i]); #ifdef CONFIG_PPC64 + if (cpu_has_feature(CPU_FTR_ARCH_300)) + device_create_file(s, &dev_attr_ldbar); + if (cpu_has_feature(CPU_FTR_MMCRA)) device_create_file(s, &dev_attr_mmcra); @@ -842,6 +847,9 @@ static int unregister_cpu_online(unsigned int cpu) device_remove_file(s, &pmc_attrs[i]); #ifdef CONFIG_PPC64 + if (cpu_has_feature(CPU_FTR_ARCH_300)) + device_remove_file(s, &dev_attr_ldbar); + if (cpu_has_feature(CPU_FTR_MMCRA)) device_remove_file(s, &dev_attr_mmcra);
Add ldbar spr to sysfs. The spr holds thread level In-Memory Collection (IMC) counter configuration data. Exposing this will help to understand the current configuration of thread-level counters in the system. Primarily, Bit 0 of ldbar says whether the counters are enabled or not. And bit 1 indicates the mode (if 0-Accumulation Mode/if 1-Trace Mode). Signed-off-by: Anju T Sudhakar <anju@linux.vnet.ibm.com> --- arch/powerpc/kernel/sysfs.c | 8 ++++++++ 1 file changed, 8 insertions(+)