linux.git/arch/powerpc/kernel/sysfs.c, branch v5.10

powerpc/sysfs: Remove unused 'err' variable in sysfs_create_dscr_default()

2020-09-18T10:05:24+00:00

This fixes a compile error with W=1.

arch/powerpc/kernel/sysfs.c: In function ‘sysfs_create_dscr_default’:
arch/powerpc/kernel/sysfs.c:228:7: error: variable ‘err’ set but not used [-Werror=unused-but-set-variable]
   int err = 0;
       ^~~
cc1: all warnings being treated as errors

Signed-off-by: Cédric Le Goater 
Reviewed-by: Christophe Leroy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200914211007.2285999-2-clg@kaod.org

powerpc/smp: Move ppc_md.cpu_die() to smp_ops.cpu_offline_self()

2020-09-18T09:59:43+00:00

We have smp_ops->cpu_die() and ppc_md.cpu_die(). One of them offlines
the current CPU and one offlines another CPU, can you guess which is
which? Also one is in smp_ops and one is in ppc_md?

So rename ppc_md.cpu_die(), to cpu_offline_self(), because that's what
it does. And move it into smp_ops where it belongs.

Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200819015634.1974478-3-mpe@ellerman.id.au

powerpc: Warn about use of smt_snooze_delay

2020-09-08T12:57:12+00:00

It's not done anything for a long time. Save the percpu variable, and
emit a warning to remind users to not expect it to do anything.

This uses pr_warn_once instead of pr_warn_ratelimit as testing
'ppc64_cpu --smt=off' on a 24 core / 4 SMT system showed the warning
to be noisy, as the online/offline loop is slow.

Fixes: 3fa8cad82b94 ("powerpc/pseries/cpuidle: smt-snooze-delay cleanup.")
Cc: stable@vger.kernel.org # v3.14
Signed-off-by: Joel Stanley 
Acked-by: Gautham R. Shenoy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200902000012.3440389-1-joel@jms.id.au

powerpc/perf: Add support for ISA3.1 PMU SPRs

2020-07-22T11:56:41+00:00

PowerISA v3.1 includes new performance monitoring unit(PMU)
special purpose registers (SPRs). They are

Monitor Mode Control Register 3 (MMCR3)
Sampled Instruction Event Register 2 (SIER2)
Sampled Instruction Event Register 3 (SIER3)

MMCR3 is added for further sampling related configuration
control. SIER2/SIER3 are added to provide additional
information about the sampled instruction.

Patch adds new PPMU flag called "PPMU_ARCH_31" to support handling of
these new SPRs, updates the struct thread_struct to include these new
SPRs, include MMCR3 in struct mmcr_regs. This is needed to support
programming of MMCR3 SPR during event_enable/disable. Patch also adds
the sysfs support for the MMCR3 SPR along with SPRN_ macros for these
new pmu SPRs.

Signed-off-by: Madhavan Srinivasan 
[mpe: Rename to PPMU_ARCH_31 as noted by jpn]
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/1594996707-3727-5-git-send-email-atrajeev@linux.vnet.ibm.com

powerpc/sysfs: Show idle_purr and idle_spurr for every CPU

2020-04-30T02:35:26+00:00

On Pseries LPARs, to calculate utilization, we need to know the
[S]PURR ticks when the CPUs were busy or idle.

The total PURR and SPURR ticks are already exposed via the per-cpu
sysfs files "purr" and "spurr". This patch adds support for exposing
the idle PURR and SPURR ticks via new per-cpu sysfs files named
"idle_purr" and "idle_spurr".

This patch also adds helper functions to accurately read the values of
idle_purr and idle_spurr especially from an interrupt context between
when the interrupt has occurred between the pseries_idle_prolog() and
pseries_idle_epilog(). This will ensure that the idle purr/spurr
values corresponding to the latest idle period is accounted for before
these values are read.

Signed-off-by: Gautham R. Shenoy 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/1586249263-14048-5-git-send-email-ego@linux.vnet.ibm.com

powerpc/kernel/sysfs: Add new config option PMU_SYSFS to enable PMU SPRs sysfs file creation

2020-03-04T11:44:28+00:00

Many of the performance monitoring unit (PMU) SPRs are
exposed in the sysfs. This may not be a desirable since
"perf" API is the primary interface to program PMU and
collect counter data in the system. But that said, we
cant remove these sysfs files since we dont whether
anyone/anything is using them.

So the patch adds a new CONFIG option 'CONFIG_PMU_SYSFS'
(user selectable) to be used in sysfs file creation for
PMU SPRs. New option by default is disabled, but can be
enabled if user needs it.

Tested this patch behaviour in powernv and pseries machines.
Patch is also tested for pmac32_defconfig.

Signed-off-by: Kajol Jain 
Tested-by: Nageswara R Sastry 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200214080606.26872-2-kjain@linux.ibm.com

powerpc/kernel/sysfs: Refactor current sysfs.c

2020-03-04T11:44:28+00:00

An attempt to refactor the current sysfs.c file.
To start with a big chuck of macro #defines and dscr
functions are moved to start of the file. Secondly,
HAS_ #define macros are cleanup based on CONFIG_ options

Finally new HAS_ macro added:
1. HAS_PPC_PA6T (for PA6T) to separate out non-PMU SPRs.
2. HAS_PPC_PMC56 to separate out PMC SPR's from HAS_PPC_PMC_CLASSIC
   which come under CONFIG_PPC64.

Signed-off-by: Madhavan Srinivasan 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20200214080606.26872-1-kjain@linux.ibm.com

powerpc/pseries/svm: Export guest SVM status to user space via sysfs

2019-08-29T23:55:41+00:00

User space might want to know it's running in a secure VM.  It can't do
a mfmsr because mfmsr is a privileged instruction.

The solution here is to create a cpu attribute:

/sys/devices/system/cpu/svm

which will read 0 or 1 based on the S bit of the current CPU.

Signed-off-by: Ryan Grimm 
Signed-off-by: Thiago Jung Bauermann 
Signed-off-by: Michael Ellerman 
Link: https://lore.kernel.org/r/20190820021326.6884-12-bauerman@linux.ibm.com

treewide: Add SPDX license identifier for missed files

2019-05-21T08:50:45+00:00

Add SPDX license identifiers to all files which:

 - Have no license information of any form

 - Have EXPORT_.*_SYMBOL_GPL inside which was used in the
   initial scan/conversion to ignore the file

These files fall under the project license, GPL v2 only. The resulting SPDX
license identifier is:

  GPL-2.0-only

Signed-off-by: Thomas Gleixner 
Signed-off-by: Greg Kroah-Hartman

powerpc: replace CONFIG_DEBUG_KERNEL with CONFIG_DEBUG_MISC

2019-05-15T02:52:50+00:00

CONFIG_DEBUG_KERNEL should not impact code generation.  Use the newly
defined CONFIG_DEBUG_MISC instead to keep the current code.

Link: http://lkml.kernel.org/r/20190413224438.10802-3-okaya@kernel.org
Signed-off-by: Sinan Kaya 
Reviewed-by: Josh Triplett 
Reviewed-by: Kees Cook 
Cc: Benjamin Herrenschmidt 
Cc: Paul Mackerras 
Cc: Michael Ellerman 
Cc: Christophe Leroy 
Cc: Anders Roxell 
Cc:  Chris Zankel 
Cc: "David S. Miller" 
Cc: Florian Westphal 
Cc: Greg Kroah-Hartman 
Cc: James Hogan 
Cc: Jozsef Kadlecsik 
Cc: Max Filippov 
Cc: Michal Hocko 
Cc: Mike Rapoport 
Cc: Pablo Neira Ayuso 
Cc: Paul Burton 
Cc: Ralf Baechle 
Cc: Thomas Bogendoerfer 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds