When I made an attempt at separating __pa_symbol and __pa I found that there
were a number of cases where __pa was used on an obvious symbol.
I also caught one non-obvious case as _brk_start and _brk_end are based on the
address of __brk_base which is a C visible symbol.
In mark_rodata_ro I was able to reduce the overhead of kernel symbol to
virtual memory translation by using a combination of __va(__pa_symbol())
instead of page_address(virt_to_page()).
Signed-off-by: Alexander Duyck <alexander.h.duyck@intel.com>
Link: http://lkml.kernel.org/r/20121116215640.8521.80483.stgit@ahduyck-cp1.jf.intel.com
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
The patch is based on a patch submitted by Hans Rosenfeld.
See http://marc.info/?l=linux-kernel&m=133908777200931
Note that CPUID Fn8000_001D_EAX slightly differs to Intel's CPUID function 4.
Bits 14-25 contain NumSharingCache. Actual number of cores sharing
this cache. SW to add value of one to get result.
The corresponding bits on Intel are defined as "maximum number of threads
sharing this cache" (with a "plus 1" encoding).
Thus a different method to determine which cores are sharing a cache
level has to be used.
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/r/20121019090209.GG26718@alberich
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Introduce cpu_has_topoext to check for AMD's CPUID topology extensions
support. It indicates support for
CPUID Fn8000_001D_EAX_x[N:0]-CPUID Fn8000_001E_EDX
See AMD's CPUID Specification, Publication # 25481
(as of Rev. 2.34 September 2010)
Signed-off-by: Andreas Herrmann <andreas.herrmann3@amd.com>
Link: http://lkml.kernel.org/r/20121019085813.GD26718@alberich
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull MCE fix from Tony Luck:
"Fix problem in CMCI rediscovery code that was illegally
migrating worker threads to other cpus."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The Way Access Filter in recent AMD CPUs may hurt the performance of
some workloads, caused by aliasing issues in the L1 cache.
This patch disables it on the affected CPUs.
The issue is similar to that one of last year:
http://lkml.indiana.edu/hypermail/linux/kernel/1107.3/00041.html
This new patch does not replace the old one, we just need another
quirk for newer CPUs.
The performance penalty without the patch depends on the
circumstances, but is a bit less than the last year's 3%.
The workloads affected would be those that access code from the same
physical page under different virtual addresses, so different
processes using the same libraries with ASLR or multiple instances of
PIE-binaries. The code needs to be accessed simultaneously from both
cores of the same compute unit.
More details can be found here:
http://developer.amd.com/Assets/SharedL1InstructionCacheonAMD15hCPU.pdf
CPUs affected are anything with the core known as Piledriver.
That includes the new parts of the AMD A-Series (aka Trinity) and the
just released new CPUs of the FX-Series (aka Vishera).
The model numbering is a bit odd here: FX CPUs have model 2,
A-Series has model 10h, with possible extensions to 1Fh. Hence the
range of model ids.
Signed-off-by: Andre Przywara <osp@andrep.de>
Link: http://lkml.kernel.org/r/1351700450-9277-1-git-send-email-osp@andrep.de
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull x86 RAS changes from Borislav Petkov:
"Rework all config variables used throughout the MCA code and collect
them together into a mca_config struct. This keeps them tightly and
neatly packed together instead of spilled all over the place.
Then, convert those which are used as booleans into real booleans and
save some space."
Signed-off-by: Ingo Molnar <mingo@kernel.org>
mce_ser, mce_bios_cmci_threshold and mce_disabled are the last three
bools which need conversion. Move them to the mca_config struct and
adjust usage sites accordingly.
Signed-off-by: Borislav Petkov <bp@alien8.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Move them into the mca_config struct and adjust code touching them
accordingly.
Signed-off-by: Borislav Petkov <bp@alien8.de>
Acked-by: Tony Luck <tony.luck@intel.com>
Move those MCA configuration variables into struct mca_config and adjust
the places they're used accordingly.
Signed-off-by: Borislav Petkov <bp@alien8.de>
Acked-by: Tony Luck <tony.luck@intel.com>
This, beyond handling corner cases, also fixes some build warnings:
arch/x86/kernel/cpu/perf_event_intel_uncore.c: In function ‘snbep_uncore_pci_disable_box’:
arch/x86/kernel/cpu/perf_event_intel_uncore.c:124:9: warning: ‘config’ is used uninitialized in this function [-Wuninitialized]
arch/x86/kernel/cpu/perf_event_intel_uncore.c: In function ‘snbep_uncore_pci_enable_box’:
arch/x86/kernel/cpu/perf_event_intel_uncore.c:135:9: warning: ‘config’ is used uninitialized in this function [-Wuninitialized]
arch/x86/kernel/cpu/perf_event_intel_uncore.c: In function ‘snbep_uncore_pci_read_counter’:
arch/x86/kernel/cpu/perf_event_intel_uncore.c:164:2: warning: ‘count’ is used uninitialized in this function [-Wuninitialized]
Signed-off-by: Yan, Zheng <zheng.z.yan@intel.com>
Cc: a.p.zijlstra@chello.nl
Link: http://lkml.kernel.org/r/1351068140-13456-1-git-send-email-zheng.z.yan@intel.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Add support to display hardware events translations available
through the sysfs. Add 'events' group attribute under the sysfs
x86 PMU record with attribute/file for each hardware event.
This patch adds only backbone for PMUs to display config under
'events' directory. The specific PMU support itself will come
in next patches, however this is how the sysfs group will look
like:
# ls /sys/devices/cpu/events/
branch-instructions
branch-misses
bus-cycles
cache-misses
cache-references
cpu-cycles
instructions
ref-cycles
stalled-cycles-backend
stalled-cycles-frontend
The file - hw event ID mapping is:
file hw event ID
---------------------------------------------------------------
cpu-cycles PERF_COUNT_HW_CPU_CYCLES
instructions PERF_COUNT_HW_INSTRUCTIONS
cache-references PERF_COUNT_HW_CACHE_REFERENCES
cache-misses PERF_COUNT_HW_CACHE_MISSES
branch-instructions PERF_COUNT_HW_BRANCH_INSTRUCTIONS
branch-misses PERF_COUNT_HW_BRANCH_MISSES
bus-cycles PERF_COUNT_HW_BUS_CYCLES
stalled-cycles-frontend PERF_COUNT_HW_STALLED_CYCLES_FRONTEND
stalled-cycles-backend PERF_COUNT_HW_STALLED_CYCLES_BACKEND
ref-cycles PERF_COUNT_HW_REF_CPU_CYCLES
Each file in the 'events' directory contains the term translation
for the symbolic hw event for the currently running cpu model.
# cat /sys/devices/cpu/events/stalled-cycles-backend
event=0xb1,umask=0x01,inv,cmask=0x01
Suggested-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Jiri Olsa <jolsa@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Corey Ashford <cjashfor@linux.vnet.ibm.com>
Cc: Frederic Weisbecker <fweisbec@gmail.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1349873598-12583-2-git-send-email-jolsa@redhat.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Between 2.6.33 and 2.6.34 the PMU code was made modular.
The x86_pmu_enable() call was extended to disable cpuc->enabled
and iterate the counters, enabling one at a time, before calling
enable_all() at the end, followed by re-enabling cpuc->enabled.
Since cpuc->enabled was set to 0, that change effectively caused
the "val |= ARCH_PERFMON_EVENTSEL_ENABLE;" code in p6_pmu_enable_event()
and p6_pmu_disable_event() to be dead code that was never called.
This change removes this code (which was confusing) and adds some
extra commentary to make it more clear what is going on.
Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1210191732000.14552@vincent-weaver-1.um.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>
In check_hw_exists() we try to detect non-emulated MSR accesses
by writing an arbitrary value into one of the PMU registers
and check if it's value after a readout is still the same.
This algorithm silently assumes that the register does not contain
the magic value already, which is wrong in at least one situation.
Fix the algorithm to really do a read-modify-write cycle. This fixes
a warning under Xen under some circumstances on AMD family 10h CPUs.
The reasons in more details actually sound like a story from
Believe It or Not!:
First you need an AMD family 10h/12h CPU. These do not reset the
PERF_CTR registers on a reboot.
Now you boot bare metal Linux, which goes successfully through this
check, but leaves the magic value of 0xabcd in the register. You
don't use the performance counters, but do a reboot (warm reset).
Then you choose to boot Xen. The check will be triggered with a
recent Linux kernel as Dom0 again, trying to write 0xabcd into the
MSR. Xen silently drops the write (expected), but the subsequent read
will return the value in the register, which just happens to be the
expected magic value. Thus the test misleadingly succeeds, leaving
the kernel in the belief that the PMU is available. This will trigger
the following message:
[ 0.020294] ------------[ cut here ]------------
[ 0.020311] WARNING: at arch/x86/xen/enlighten.c:730 xen_apic_write+0x15/0x17()
[ 0.020318] Hardware name: empty
[ 0.020323] Modules linked in:
[ 0.020334] Pid: 1, comm: swapper/0 Not tainted 3.3.8 #7
[ 0.020340] Call Trace:
[ 0.020354] [<ffffffff81050379>] warn_slowpath_common+0x80/0x98
[ 0.020369] [<ffffffff810503a6>] warn_slowpath_null+0x15/0x17
[ 0.020378] [<ffffffff810034df>] xen_apic_write+0x15/0x17
[ 0.020392] [<ffffffff8101cb2b>] perf_events_lapic_init+0x2e/0x30
[ 0.020410] [<ffffffff81ee4dd0>] init_hw_perf_events+0x250/0x407
[ 0.020419] [<ffffffff81ee4b80>] ? check_bugs+0x2d/0x2d
[ 0.020430] [<ffffffff81002181>] do_one_initcall+0x7a/0x131
[ 0.020444] [<ffffffff81edbbf9>] kernel_init+0x91/0x15d
[ 0.020456] [<ffffffff817caaa4>] kernel_thread_helper+0x4/0x10
[ 0.020471] [<ffffffff817c347c>] ? retint_restore_args+0x5/0x6
[ 0.020481] [<ffffffff817caaa0>] ? gs_change+0x13/0x13
[ 0.020500] ---[ end trace a7919e7f17c0a725 ]---
The new code will change every of the 16 low bits read from the
register and tries to write and read-back that modified number
from the MSR.
Signed-off-by: Andre Przywara <andre.przywara@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Arnaldo Carvalho de Melo <acme@redhat.com>
Cc: Avi Kivity <avi@redhat.com>
Link: http://lkml.kernel.org/r/1349797115-28346-2-git-send-email-andre.przywara@amd.com
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Pull perf fixes from Ingo Molnar:
"Assorted small fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf python: Properly link with libtraceevent
perf hists browser: Add back callchain folding symbol
perf tools: Fix build on sparc.
perf python: Link with libtraceevent
perf python: Initialize 'page_size' variable
tools lib traceevent: Fix missed freeing of subargs in free_arg() in filter
lib tools traceevent: Add back pevent assignment in __pevent_parse_format()
perf hists browser: Fix off-by-two bug on the first column
perf tools: Remove warnings on JIT samples for srcline sort key
perf tools: Fix segfault when using srcline sort key
perf: Require exclude_guest to use PEBS - kernel side enforcement
perf tool: Precise mode requires exclude_guest
Pull perf/urgent fixes from Arnaldo Carvalho de Melo:
* The python binding needs to link with libtraceevent and to initialize
the 'page_size' variable so that mmaping works again.
* The callchain folding character that appears on the TUI just before
the overhead had disappeared due to recent changes, add it back.
* Intel PEBS in VT-x context uses the DS address as a guest linear address,
even though its programmed by the host as a host linear address. This either
results in guest memory corruption and or the hardware faulting and 'crashing'
the virtual machine. Therefore we have to disable PEBS on VT-x enter and
re-enable on VT-x exit, enforcing a strict exclude_guest.
Kernel side enforcement fix by Peter Zijlstra, tooling side fix by David Ahern.
* Fix build on sparc due to UAPI, fix from David Miller.
* Fixes for the srclike sort key for unresolved symbols and when processing
samples in JITted code, where we don't have an ELF file, just an special
symbol table, fixes from Namhyung Kim.
* Fix some leaks in libtraceevent, from Steven Rostedt.
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
From Borislav Petkov <bp@amd64.org>:
Below is a RAS fix which reverts the addition of a sysfs attribute
which we agreed is not needed, post-factum. And this should go in now
because that sysfs attribute is going to end up in 3.7 otherwise and
thus exposed to userspace; removing it then would be a lot harder.
This is done as a merge rather than a simple patch/cherry-pick since
the baseline for this patch was not in the previous x86/urgent.
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
450cc20103 ("x86/mce: Provide boot argument to honour bios-set CMCI
threshold") added the bios_cmci_threshold sysfs attribute which was
supposed to communicate to userspace tools that BIOS CMCI threshold has
been honoured.
However, this info is not of any importance to userspace - it should
rather get the actual error count it has been thresholded already from
MCi_STATUS[38:52].
So drop this before it becomes a used interface (good thing we caught
this early in 3.7-rc1, right after the merge window closed).
Cc: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
Acked-by: Tony Luck <tony.luck@intel.com>
Link: http://lkml.kernel.org/r/20121017105940.GA14590@x1.osrc.amd.com
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
When booting on a federated multi-server system (NumaScale), the
processor Northbridge lookup returns NULL; add guards to prevent this
causing an oops.
On those systems, the northbridge is accessed through MMIO and the
"normal" northbridge enumeration in amd_nb.c doesn't work since we're
generating the northbridge ID from the initial APIC ID and the last
is not unique on those systems. Long story short, we end up without
northbridge descriptors.
Signed-off-by: Daniel J Blueman <daniel@numascale-asia.com>
Cc: stable@vger.kernel.org # 3.6
Link: http://lkml.kernel.org/r/1349073725-14093-1-git-send-email-daniel@numascale-asia.com
[ Boris: beef up commit message ]
Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>
Pull perf updates from Ingo Molnar:
"This tree includes some late late perf items that missed the first
round:
tools:
- Bash auto completion improvements, now we can auto complete the
tools long options, tracepoint event names, etc, from Namhyung Kim.
- Look up thread using tid instead of pid in 'perf sched'.
- Move global variables into a perf_kvm struct, from David Ahern.
- Hists refactorings, preparatory for improved 'diff' command, from
Jiri Olsa.
- Hists refactorings, preparatory for event group viewieng work, from
Namhyung Kim.
- Remove double negation on optional feature macro definitions, from
Namhyung Kim.
- Remove several cases of needless global variables, on most
builtins.
- misc fixes
kernel:
- sysfs support for IBS on AMD CPUs, from Robert Richter.
- Support for an upcoming Intel CPU, the Xeon-Phi / Knights Corner
HPC blade PMU, from Vince Weaver.
- misc fixes"
* 'perf-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (46 commits)
perf: Fix perf_cgroup_switch for sw-events
perf: Clarify perf_cpu_context::active_pmu usage by renaming it to ::unique_pmu
perf/AMD/IBS: Add sysfs support
perf hists: Add more helpers for hist entry stat
perf hists: Move he->stat.nr_events initialization to a template
perf hists: Introduce struct he_stat
perf diff: Removing the total_period argument from output code
perf tool: Add hpp interface to enable/disable hpp column
perf tools: Removing hists pair argument from output path
perf hists: Separate overhead and baseline columns
perf diff: Refactor diff displacement possition info
perf hists: Add struct hists pointer to struct hist_entry
perf tools: Complete tracepoint event names
perf/x86: Add support for Intel Xeon-Phi Knights Corner PMU
perf evlist: Remove some unused methods
perf evlist: Introduce add_newtp method
perf kvm: Move global variables into a perf_kvm struct
perf tools: Convert to BACKTRACE_SUPPORT
perf tools: Long option completion support for each subcommands
perf tools: Complete long option names of perf command
...
Add sysfs format entries for AMD IBS PMUs:
# find /sys/bus/event_source/devices/ibs_*/format
/sys/bus/event_source/devices/ibs_fetch/format
/sys/bus/event_source/devices/ibs_fetch/format/rand_en
/sys/bus/event_source/devices/ibs_op/format
/sys/bus/event_source/devices/ibs_op/format/cnt_ctl
This allows to specify following IBS options:
$ perf record -e ibs_fetch/rand_en=1/GH ...
$ perf record -e ibs_op/cnt_ctl=1/GH ...
Option cnt_ctl is only enabled if the IBS_CAPS_OPCNT bit is set in IBS
cpuid feature flags (AMD family 10h RevC and above).
Signed-off-by: Robert Richter <robert.richter@amd.com>
Signed-off-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Link: http://lkml.kernel.org/r/1347447584-28405-1-git-send-email-robert.richter@amd.com
[ Added small readability improvements. ]
Signed-off-by: Ingo Molnar <mingo@kernel.org>
The following patch adds perf_event support for the Xeon-Phi
PMU, as documented in the "Intel Xeon Phi Coprocessor (codename:
Knights Corner) Performance Monitoring Units" manual.
Even though it is a co-processor, a Phi runs a full Linux
environment and can support performance counters.
This is just barebones support, it does not add support for
interesting new features such as the SPFLT intruction that
allows starting/stopping events without entering the kernel.
The PMU internally is just like that of an original Pentium, but
a "P6-like" MSR interface is provided. The interface is
different enough from a real P6 that it's not easy (or
practical) to re-use the code in perf_event_p6.c
Acked-by: Lawrence F Meadows <lawrence.f.meadows@intel.com>
Acked-by: Cyrill Gorcunov <gorcunov@openvz.org>
Signed-off-by: Vince Weaver <vincent.weaver@maine.edu>
Acked-by: Peter Zijlstra <a.p.zijlstra@chello.nl>
Cc: Paul Mackerras <paulus@samba.org>
Cc: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Cc: eranian@gmail.com
Cc: Lawrence F <lawrence.f.meadows@intel.com>
Link: http://lkml.kernel.org/r/alpine.DEB.2.02.1209261405320.8398@vincent-weaver-1.um.maine.edu
Signed-off-by: Ingo Molnar <mingo@kernel.org>
