dev_attr_show() calls the __uncore_*_show() functions via an indirect
call but their type does not currently match the type of the show()
member in 'struct device_attribute', resulting in a Control Flow
Integrity violation.
$ cat /sys/devices/amd_l3/format/umask
config:8-15
$ dmesg | grep "CFI failure"
[ 1258.174653] CFI failure (target: __uncore_umask_show...):
Update the type in the DEFINE_UNCORE_FORMAT_ATTR macro to match
'struct device_attribute' so that there is no more CFI violation.
Fixes: 06f2c24584 ("perf/amd/uncore: Prepare to scale for more attributes that vary per family")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20210415001112.3024673-2-nathan@kernel.org
Previously, the uncore driver would say "NB counters detected" on F17h
machines, which don't have NorthBridge (NB) counters. They have Data
Fabric (DF) counters. Just use the pmu.name to inform users which pmu
to use and its associated counter count.
F17h dmesg BEFORE:
amd_uncore: AMD NB counters detected
amd_uncore: AMD LLC counters detected
F17h dmesg AFTER:
amd_uncore: 4 amd_df counters detected
amd_uncore: 6 amd_l3 counters detected
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-5-kim.phillips@amd.com
On Family 19h, the driver checks for a populated 2-bit threadmask in
order to establish that the user wants to measure individual slices,
individual cores (only one can be measured at a time), and lets
the user also directly specify enallcores and/or enallslices if
desired.
Example F19h invocation to measure L3 accesses (event 4, umask 0xff)
by the first thread (id 0 -> mask 0x1) of the first core (id 0) on the
first slice (id 0):
perf stat -a -e instructions,amd_l3/umask=0xff,event=0x4,coreid=0,threadmask=1,sliceid=0,enallcores=0,enallslices=0/ <workload>
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-4-kim.phillips@amd.com
Continue to fully populate either one of threadmask or slicemask if the
user doesn't.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-3-kim.phillips@amd.com
Replace AMD_FORMAT_ATTR with the more apropos DEFINE_UNCORE_FORMAT_ATTR
stolen from arch/x86/events/intel/uncore.h. This way we can clearly
see the bit-variants of each of the attributes that want to have
the same name across families.
Also unroll AMD_ATTRIBUTE because we are going to separately add
new attributes that differ between DF and L3.
Also clean up the if-Family 17h-else logic in amd_uncore_init.
This is basically a rewrite of commit da6adaea2b
("perf/x86/amd/uncore: Update sysfs attributes for Family17h processors").
No functional changes.
Tested F17h+ /sys/bus/event_source/devices/amd_{l3,df}/format/*
content remains unchanged:
/sys/bus/event_source/devices/amd_l3/format/event:config:0-7
/sys/bus/event_source/devices/amd_l3/format/umask:config:8-15
/sys/bus/event_source/devices/amd_df/format/event:config:0-7,32-35,59-60
/sys/bus/event_source/devices/amd_df/format/umask:config:8-15
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200921144330.6331-2-kim.phillips@amd.com
Commit 2f217d58a8 ("perf/x86/amd/uncore: Set the thread mask for
F17h L3 PMCs") inadvertently changed the uncore driver's behaviour
wrt perf tool invocations with or without a CPU list, specified with
-C / --cpu=.
Change the behaviour of the driver to assume the former all-cpu (-a)
case, which is the more commonly desired default. This fixes
'-a -A' invocations without explicit cpu lists (-C) to not count
L3 events only on behalf of the first thread of the first core
in the L3 domain.
BEFORE:
Activity performed by the first thread of the last core (CPU#43) in
CPU#40's L3 domain is not reported by CPU#40:
sudo perf stat -a -A -e l3_request_g1.caching_l3_cache_accesses taskset -c 43 perf bench mem memcpy -s 32mb -l 100 -f default
...
CPU36 21,835 l3_request_g1.caching_l3_cache_accesses
CPU40 87,066 l3_request_g1.caching_l3_cache_accesses
CPU44 17,360 l3_request_g1.caching_l3_cache_accesses
...
AFTER:
The L3 domain activity is now reported by CPU#40:
sudo perf stat -a -A -e l3_request_g1.caching_l3_cache_accesses taskset -c 43 perf bench mem memcpy -s 32mb -l 100 -f default
...
CPU36 354,891 l3_request_g1.caching_l3_cache_accesses
CPU40 1,780,870 l3_request_g1.caching_l3_cache_accesses
CPU44 315,062 l3_request_g1.caching_l3_cache_accesses
...
Fixes: 2f217d58a8 ("perf/x86/amd/uncore: Set the thread mask for F17h L3 PMCs")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200908214740.18097-2-kim.phillips@amd.com
Family 19h introduces change in slice, core and thread specification in
its L3 Performance Event Select (ChL3PmcCfg) h/w register. The change is
incompatible with Family 17h's version of the register.
Introduce a new path in l3_thread_slice_mask() to do things differently
for Family 19h vs. Family 17h, otherwise the new hardware doesn't get
programmed correctly.
Instead of a linear core--thread bitmask, Family 19h takes an encoded
core number, and a separate thread mask. There are new bits that are set
for all cores and all slices, of which only the latter is used, since
the driver counts events for all slices on behalf of the specified CPU.
Also update amd_uncore_init() to base its L2/NB vs. L3/Data Fabric mode
decision based on Family 17h or above, not just 17h and 18h: the Family
19h Data Fabric PMC is compatible with the Family 17h DF PMC.
[ bp: Touchups. ]
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200313231024.17601-3-kim.phillips@amd.com
Convert the l3_thread_slice_mask() function to use the more readable
topology_* helper functions, more intuitive variable names like shift
and thread_mask, and BIT_ULL().
No functional changes.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200313231024.17601-2-kim.phillips@amd.com
In order to better accommodate the upcoming Family 19h, given
the 80-char line limit, move the existing code into a new
l3_thread_slice_mask() function.
No functional changes.
[ bp: Touchups. ]
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200313231024.17601-1-kim.phillips@amd.com
Enable the sampling check in kernel/events/core.c::perf_event_open(),
which returns the more appropriate -EOPNOTSUPP.
BEFORE:
$ sudo perf record -a -e instructions,l3_request_g1.caching_l3_cache_accesses true
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument) for event (l3_request_g1.caching_l3_cache_accesses).
/bin/dmesg | grep -i perf may provide additional information.
With nothing relevant in dmesg.
AFTER:
$ sudo perf record -a -e instructions,l3_request_g1.caching_l3_cache_accesses true
Error:
l3_request_g1.caching_l3_cache_accesses: PMU Hardware doesn't support sampling/overflow-interrupts. Try 'perf stat'
Fixes: c43ca5091a ("perf/x86/amd: Add support for AMD NB and L2I "uncore" counters")
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200311191323.13124-1-kim.phillips@amd.com
The following commit:
d7cbbe49a9 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events")
enables L3 PMC events for all threads and slices by writing 1's in
'ChL3PmcCfg' (L3 PMC PERF_CTL) register fields.
Those bitfields overlap with high order event select bits in the Data
Fabric PMC control register, however.
So when a user requests raw Data Fabric events (-e amd_df/event=0xYYY/),
the two highest order bits get inadvertently set, changing the counter
select to events that don't exist, and for which no counts are read.
This patch changes the logic to write the L3 masks only when dealing
with L3 PMC counters.
AMD Family 16h and below Northbridge (NB) counters were not affected.
Signed-off-by: Kim Phillips <kim.phillips@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: <stable@vger.kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Gary Hook <Gary.Hook@amd.com>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Martin Liska <mliska@suse.cz>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Pu Wen <puwen@hygon.cn>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Fixes: d7cbbe49a9 ("perf/x86/amd/uncore: Set ThreadMask and SliceMask for L3 Cache perf events")
Link: https://lkml.kernel.org/r/20190628215906.4276-1-kim.phillips@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Based on 2 normalized pattern(s):
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation
this program is free software you can redistribute it and or modify
it under the terms of the gnu general public license version 2 as
published by the free software foundation #
extracted by the scancode license scanner the SPDX license identifier
GPL-2.0-only
has been chosen to replace the boilerplate/reference in 4122 file(s).
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Enrico Weigelt <info@metux.net>
Reviewed-by: Kate Stewart <kstewart@linuxfoundation.org>
Reviewed-by: Allison Randal <allison@lohutok.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190604081206.933168790@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
For x86 PMUs that do not support context exclusion let's advertise the
PERF_PMU_CAP_NO_EXCLUDE capability. This ensures that perf will
prevent us from handling events where any exclusion flags are set.
Let's also remove the now unnecessary check for exclusion flags.
This change means that amd/iommu and amd/uncore will now also
indicate that they do not support exclude_{hv|idle} and intel/uncore
that it does not support exclude_{guest|host}.
Signed-off-by: Andrew Murray <andrew.murray@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Ivan Kokshaysky <ink@jurassic.park.msu.ru>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Matt Turner <mattst88@gmail.com>
Cc: Michael Ellerman <mpe@ellerman.id.au>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Richard Henderson <rth@twiddle.net>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Sascha Hauer <s.hauer@pengutronix.de>
Cc: Shawn Guo <shawnguo@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linuxppc-dev@lists.ozlabs.org
Cc: robin.murphy@arm.com
Cc: suzuki.poulose@arm.com
Link: https://lkml.kernel.org/r/1547128414-50693-12-git-send-email-andrew.murray@arm.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull x86 cpu updates from Ingo Molnar:
"The main changes in this cycle were:
- Add support for the "Dhyana" x86 CPUs by Hygon: these are licensed
based on the AMD Zen architecture, and are built and sold in China,
for domestic datacenter use. The code is pretty close to AMD
support, mostly with a few quirks and enumeration differences. (Pu
Wen)
- Enable CPUID support on Cyrix 6x86/6x86L processors"
* 'x86-cpu-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tools/cpupower: Add Hygon Dhyana support
cpufreq: Add Hygon Dhyana support
ACPI: Add Hygon Dhyana support
x86/xen: Add Hygon Dhyana support to Xen
x86/kvm: Add Hygon Dhyana support to KVM
x86/mce: Add Hygon Dhyana support to the MCA infrastructure
x86/bugs: Add Hygon Dhyana to the respective mitigation machinery
x86/apic: Add Hygon Dhyana support
x86/pci, x86/amd_nb: Add Hygon Dhyana support to PCI and northbridge
x86/amd_nb: Check vendor in AMD-only functions
x86/alternative: Init ideal_nops for Hygon Dhyana
x86/events: Add Hygon Dhyana support to PMU infrastructure
x86/smpboot: Do not use BSP INIT delay and MWAIT to idle on Dhyana
x86/cpu/mtrr: Support TOP_MEM2 and get MTRR number
x86/cpu: Get cache info and setup cache cpumap for Hygon Dhyana
x86/cpu: Create Hygon Dhyana architecture support file
x86/CPU: Change query logic so CPUID is enabled before testing
x86/CPU: Use correct macros for Cyrix calls
In Family 17h, some L3 Cache Performance events require the ThreadMask
and SliceMask to be set. For other events, these fields do not affect
the count either way.
Set ThreadMask and SliceMask to 0xFF and 0xF respectively.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: H . Peter Anvin <hpa@zytor.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee <Suravee.Suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/Message-ID:
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Current logic iterates over CPUID Fn8000001d leafs (Cache Properties)
to detect the last level cache, and derive the last-level cache ID.
However, this information is already available in the cpu_llc_id.
Therefore, make use of it instead.
Signed-off-by: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "Peter Zijlstra (Intel)" <peterz@infradead.org>
Cc: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Link: http://lkml.kernel.org/r/1524864877-111962-3-git-send-email-suravee.suthikulpanit@amd.com
In Family 17h, the number of cores sharing a cache level is obtained
from the Cache Properties CPUID leaf (0x8000001d) by passing in the
cache level in ECX. In prior families, a cache level of 2 was used to
determine this information.
To get the right information, irrespective of Family, iterate over
the cache levels using CPUID 0x8000001d. The last level cache is the
last value to return a non-zero value in EAX.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/5ab569025b39cdfaeca55b571d78c0fc800bdb69.1497452002.git.Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In Family 17h, L3 is the last level cache as opposed to L2 in previous
families. Avoid this name confusion and rename X86_FEATURE_PERFCTR_L2 to
X86_FEATURE_PERFCTR_LLC to indicate the performance counter on the last
level of cache.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Link: http://lkml.kernel.org/r/016311029fdecdc3fdc13b7ed865c6cbf48b2f15.1497452002.git.Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Fam16h is the same as the default one, remove it. Turn the switch-case
into a simple if-else.
No functionality change.
Signed-off-by: Borislav Petkov <bp@suse.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <Suravee.Suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/20170410122047.3026-3-bp@alien8.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch updates the sysfs attributes for AMD Family17h processors. In
Family17h, the event bit position is changed for both the NorthBridge
and Last level cache counters.
The sysfs attributes are assigned based on the family and the type of
the counter.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/617570ed3634e804991f95db62c3cf3856a9d2a7.1484598705.git.Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch updates the AMD uncore driver to support AMD Family17h
processors. In Family17h, there are two extra last level cache counters.
The maximum available counters is increased and the number of counters
for each uncore type is now based on the family.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/799f9c5be8963cc209d9169a08f4a2643b748dc7.1484598705.git.Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
This patch renames L2 counters to LLC counters. In AMD Family17h
processors, L3 cache counter is supported.
Since older families have at most L2 counters, last level cache (LLC)
indicates L2/L3 based on the family.
Signed-off-by: Janakarajan Natarajan <Janakarajan.Natarajan@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Suravee Suthikulpanit <suravee.suthikulpanit@amd.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Link: http://lkml.kernel.org/r/5d8cd8736d8d578354597a548e64ff16210c319b.1484598705.git.Janakarajan.Natarajan@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
When the state names got added a script was used to add the extra argument
to the calls. The script basically converted the state constant to a
string, but the cleanup to convert these strings into meaningful ones did
not happen.
Replace all the useless strings with 'subsys/xxx/yyy:state' strings which
are used in all the other places already.
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Sebastian Siewior <bigeasy@linutronix.de>
Link: http://lkml.kernel.org/r/20161221192112.085444152@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
The resent conversion of the cpu hotplug support in the uncore driver
introduced a regression due to the way the callbacks are invoked at
initialization time.
The old code called the prepare/starting/online function on each online cpu
as a block. The new code registers the hotplug callbacks in the core for
each state. The core invokes the callbacks at each registration on all
online cpus.
The code implicitely relied on the prepare/starting/online callbacks being
called as combo on a particular cpu, which was not obvious and completely
undocumented.
The resulting subtle wreckage happens due to the way how the uncore code
manages shared data structures for cpus which share an uncore resource in
hardware. The sharing is determined in the cpu starting callback, but the
prepare callback allocates per cpu data for the upcoming cpu because
potential sharing is unknown at this point. If the starting callback finds
a online cpu which shares the hardware resource it takes a refcount on the
percpu data of that cpu and puts the own data structure into a
'free_at_online' pointer of that shared data structure. The online callback
frees that.
With the old model this worked because in a starting callback only one non
unused structure (the one of the starting cpu) was available. The new code
allocates the data structures for all cpus when the prepare callback is
registered.
Now the starting function iterates through all online cpus and looks for a
data structure (skipping its own) which has a matching hardware id. The id
member of the data structure is initialized to 0, but the hardware id can
be 0 as well. The resulting wreckage is:
CPU0 finds a matching id on CPU1, takes a refcount on CPU1 data and puts
its own data structure into CPU1s data structure to be freed.
CPU1 skips CPU0 because the data structure is its allegedly unsued own.
It finds a matching id on CPU2, takes a refcount on CPU1 data and puts
its own data structure into CPU2s data structure to be freed.
....
Now the online callbacks are invoked.
CPU0 has a pointer to CPU1s data and frees the original CPU0 data. So
far so good.
CPU1 has a pointer to CPU2s data and frees the original CPU1 data, which
is still referenced by CPU0 ---> Booom
So there are two issues to be solved here:
1) The id field must be initialized at allocation time to a value which
cannot be a valid hardware id, i.e. -1
This prevents the above scenario, but now CPU1 and CPU2 both stick their
own data structure into the free_at_online pointer of CPU0. So we leak
CPU1s data structure.
2) Fix the memory leak described in #1
Instead of having a single pointer, use a hlist to enqueue the
superflous data structures which are then freed by the first cpu
invoking the online callback.
Ideally we should know the sharing _before_ invoking the prepare callback,
but that's way beyond the scope of this bug fix.
[ tglx: Rewrote changelog ]
Fixes: 96b2bd3866 ("perf/x86/amd/uncore: Convert to hotplug state machine")
Reported-and-tested-by: Eric Sandeen <sandeen@sandeen.net>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Borislav Petkov <bp@suse.de>
Link: http://lkml.kernel.org/r/20160909160822.lowgmkdwms2dheyv@linutronix.de
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Install the callbacks via the state machine and let the core invoke
the callbacks on the already online CPUs.
Signed-off-by: Richard Cochran <rcochran@linutronix.de>
Signed-off-by: Anna-Maria Gleixner <anna-maria@linutronix.de>
Reviewed-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Borislav Petkov <bp@suse.de>
Cc: Chen Yucong <slaoub@gmail.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vince Weaver <vincent.weaver@maine.edu>
Cc: rt@linutronix.de
Link: http://lkml.kernel.org/r/20160713153333.839150380@linutronix.de
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Nathan Chancellor
Kim Phillips
Ingo Molnar
Thomas Gleixner
Andrew Murray
Linus Torvalds
Natarajan, Janakarajan
Pu Wen
Suravee Suthikulpanit
Borislav Petkov
Sebastian Andrzej Siewior
Richard Cochran
Peter Zijlstra