linux-xiaomi-chiron/Documentation
Vaibhav Jain ed78f56e12 powerpc/papr_scm: Make 'perf_stats' invisible if perf-stats unavailable
In case performance stats for an nvdimm are not available, reading the
'perf_stats' sysfs file returns an -ENOENT error. A better approach is
to make the 'perf_stats' file entirely invisible to indicate that
performance stats for an nvdimm are unavailable.

So this patch updates 'papr_nd_attribute_group' to add a 'is_visible'
callback implemented as newly introduced 'papr_nd_attribute_visible()'
that returns an appropriate mode in case performance stats aren't
supported in a given nvdimm.

Also the initialization of 'papr_scm_priv.stat_buffer_len' is moved
from papr_scm_nvdimm_init() to papr_scm_probe() so that it value is
available when 'papr_nd_attribute_visible()' is called during nvdimm
initialization.

Even though 'perf_stats' attribute is available since v5.9, there are
no known user-space tools/scripts that are dependent on presence of its
sysfs file. Hence I dont expect any user-space breakage with this
patch.

Fixes: 2d02bf835e ("powerpc/papr_scm: Fetch nvdimm performance stats from PHYP")
Signed-off-by: Vaibhav Jain <vaibhav@linux.ibm.com>
Reviewed-by: Dan Williams <dan.j.williams@intel.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210513092349.285021-1-vaibhav@linux.ibm.com
2021-06-25 14:47:18 +10:00
..
ABI powerpc/papr_scm: Make 'perf_stats' invisible if perf-stats unavailable 2021-06-25 14:47:18 +10:00
accounting
admin-guide docs: admin-guide: update description for kernel.modprobe sysctl 2021-05-14 19:41:32 -07:00
arm
arm64 Assorted arm64 fixes and clean-ups, the most important: 2021-05-07 12:11:05 -07:00
block Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
bpf
cdrom docs: cdrom-standard.rst: get rid of uneeded UTF-8 chars 2021-05-11 11:00:17 -06:00
core-api
cpu-freq
crypto
dev-tools scripts/gdb: add lx_current support for arm64 2021-05-07 00:26:33 -07:00
devicetree Kbuild updates for v5.13 (2nd) 2021-05-08 10:00:11 -07:00
doc-guide
driver-api USB fixes for 5.13-rc2 2021-05-16 09:55:05 -07:00
fault-injection
fb
features
filesystems erofs: update documentation about data compression 2021-05-11 16:47:15 +08:00
firmware-guide
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hid
hwmon docs: hwmon: tmp103.rst: fix bad usage of UTF-8 chars 2021-05-11 11:00:18 -06:00
i2c
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nios2
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openrisc
parisc
PCI
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power
powerpc powerpc/64s/syscall: Use pt_regs.trap to distinguish syscall ABI difference between sc and scv syscalls 2021-05-21 00:58:03 +10:00
process Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
RCU
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security Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
sh
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timers Documentation: drop optional BOMs 2021-05-10 15:17:34 -06:00
trace
translations docs/zh_CN: Remove obsolete translation file 2021-05-10 15:14:31 -06:00
usb USB fixes for 5.13-rc2 2021-05-16 09:55:05 -07:00
userspace-api
virt KVM: PPC: Book3S HV: Add KVM_CAP_PPC_RPT_INVALIDATE capability 2021-06-22 23:38:28 +10:00
vm
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x86 x86/msr: Rename MSR_K8_SYSCFG to MSR_AMD64_SYSCFG 2021-05-10 07:51:38 +02:00
xtensa
.gitignore
arch.rst
asm-annotations.rst
atomic_bitops.txt
atomic_t.txt
Changes
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conf.py
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docutils.conf
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index.rst
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memory-barriers.txt
SubmittingPatches
watch_queue.rst