- 05 Dec, 2018 1 commit
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Jiri Olsa authored
commit ed6101bb upstream. Moving branch tracing setup to Intel core object into separate intel_pmu_bts_config function, because it's Intel specific. Suggested-by:
Peter Zijlstra <peterz@infradead.org> Signed-off-by:
Jiri Olsa <jolsa@kernel.org> Acked-by:
Peter Zijlstra <a.p.zijlstra@chello.nl> Cc: <stable@vger.kernel.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: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Link: http://lkml.kernel.org/r/20181121101612.16272-1-jolsa@kernel.orgSigned-off-by:
Ingo Molnar <mingo@kernel.org> Signed-off-by:
Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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- 20 Jun, 2018 1 commit
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Kan Liang authored
[ Upstream commit 4e949e9b ] The SMM freeze feature was introduced since PerfMon V2. But the current code unconditionally enables the feature for all platforms. It can generate #GP exception, if the related FREEZE_WHILE_SMM bit is set for the machine with PerfMon V1. To disable the feature for PerfMon V1, perf needs to - Remove the freeze_on_smi sysfs entry by moving intel_pmu_attrs to intel_pmu, which is only applied to PerfMon V2 and later. - Check the PerfMon version before flipping the SMM bit when starting CPU Fixes: 6089327f ("perf/x86: Add sysfs entry to freeze counters on SMI") Signed-off-by:
Kan Liang <kan.liang@linux.intel.com> Signed-off-by:
Thomas Gleixner <tglx@linutronix.de> Acked-by:
Sasha Levin <alexander.levin@microsoft.com> Signed-off-by:
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- 30 May, 2018 2 commits
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Kan Liang authored
[ Upstream commit f605cfca ] Large fixed period values could be truncated on Broadwell, for example: perf record -e cycles -c 10000000000 Here the fixed period is 0x2540BE400, but the period which finally applied is 0x540BE400 - which is wrong. The reason is that x86_pmu::limit_period() uses an u32 parameter, so the high 32 bits of 'period' get truncated. This bug was introduced in: commit 294fe0f5 ("perf/x86/intel: Add INST_RETIRED.ALL workarounds") It's safe to use u64 instead of u32: - Although the 'left' is s64, the value of 'left' must be positive when calling limit_period(). - bdw_limit_period() only modifies the lowest 6 bits, it doesn't touch the higher 32 bits. Signed-off-by:
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Kan Liang authored
[ Upstream commit 82d71ed0 ] The PMU is disabled in intel_pmu_handle_irq(), but cpuc->enabled is not updated accordingly. This is fine in current usage because no-one checks it - but fix it for future code: for example, the drain_pebs() will be modified to fix an auto-reload bug. Properly save/restore the old PMU state. Signed-off-by:
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- 28 Mar, 2018 1 commit
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Dan Carpenter authored
commit e5ea9b54 upstream. We intended to clear the lowest 6 bits but because of a type bug we clear the high 32 bits as well. Andi says that periods are rarely more than U32_MAX so this bug probably doesn't have a huge runtime impact. Signed-off-by:
Dan Carpenter <dan.carpenter@oracle.com> Signed-off-by:
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- 03 Mar, 2018 1 commit
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Thomas Gleixner authored
[ Upstream commit 7ad1437d ] A recent commit introduced an extra merge_attr() call in the skylake branch, which causes a memory leak. Store the pointer to the extra allocated memory and free it at the end of the function. Fixes: a5df70c3 ("perf/x86: Only show format attributes when supported") Reported-by:
Tommi Rantala <tommi.t.rantala@nokia.com> Signed-off-by:
Sasha Levin <alexander.levin@verizon.com> Signed-off-by:
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- 22 Feb, 2018 1 commit
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Jia Zhang authored
commit b399151c upstream. x86_mask is a confusing name which is hard to associate with the processor's stepping. Additionally, correct an indent issue in lib/cpu.c. Signed-off-by:
Jia Zhang <qianyue.zj@alibaba-inc.com> [ Updated it to more recent kernels. ] Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: bp@alien8.de Cc: tony.luck@intel.com Link: http://lkml.kernel.org/r/1514771530-70829-1-git-send-email-qianyue.zj@alibaba-inc.comSigned-off-by:
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- 25 Dec, 2017 1 commit
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Andi Kleen authored
commit 2fe1bc1f upstream. [ Note, this is a Git cherry-pick of the following commit: a47ba4d7 ("perf/x86: Enable free running PEBS for REGS_USER/INTR") ... for easier x86 PTI code testing and back-porting. ] Currently free running PEBS is disabled when user or interrupt registers are requested. Most of the registers are actually available in the PEBS record and can be supported. So we just need to check for the supported registers and then allow it: it is all except for the segment register. For user registers this only works when the counter is limited to ring 3 only, so this also needs to be checked. Signed-off-by:
Andi Kleen <ak@linux.intel.com> Signed-off-by:
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- 30 Nov, 2017 1 commit
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Andi Kleen authored
commit 58ba4d5a upstream. 0day testing reported a perf test regression on Haswell systems without RTM. Commit a5df70c3 hides the in_tx/in_tx_cp attributes when RTM is not available, but the TSX events are still available in sysfs. Due to the missing attributes the event parser fails on those files. Don't show the TSX events in sysfs when RTM is not available on Haswell/Broadwell/Skylake. Fixes: a5df70c3 (perf/x86: Only show format attributes when supported) Reported-by:
kernel test robot <xiaolong.ye@intel.com> Tested-by:
Jin Yao <yao.jin@linux.intel.com> Signed-off-by:
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- 14 Sep, 2017 1 commit
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Peter Zijlstra authored
The lockup_detector_suspend/resume() interface is broken in several ways especially as it results in recursive locking of the CPU hotplug lock. Use the new stop/restart interface in the perf NMI watchdog to temporarily disable and reenable the already active watchdog events. That's enough to handle it. Signed-off-by:
Don Zickus <dzickus@redhat.com> Cc: Andrew Morton <akpm@linux-foundation.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Chris Metcalf <cmetcalf@mellanox.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Nicholas Piggin <npiggin@gmail.com> Cc: Sebastian Siewior <bigeasy@linutronix.de> Cc: Ulrich Obergfell <uobergfe@redhat.com> Link: http://lkml.kernel.org/r/20170912194146.247141871@linutronix.deSigned-off-by:
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- 29 Aug, 2017 1 commit
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Peter Zijlstra authored
Move the 'max_precise' capability into generic x86 code where it belongs. This fixes a sysfs splat on !Intel systems where we fail to set x86_pmu_caps_group.atts. Reported-and-tested-by:
Borislav Petkov <bp@suse.de> Signed-off-by:
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- 25 Aug, 2017 4 commits
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Andi Kleen authored
It can be difficult to figure out for user programs what features the x86 CPU PMU driver actually supports. Currently it requires grepping in dmesg, but dmesg is not always available. This adds a caps directory to /sys/bus/event_source/devices/cpu/, similar to the caps already used on intel_pt, which can be used to discover the available capabilities cleanly. Three capabilities are defined: - pmu_name: Underlying CPU name known to the driver - max_precise: Max precise level supported - branches: Known depth of LBR. Example: % grep . /sys/bus/event_source/devices/cpu/caps/* /sys/bus/event_source/devices/cpu/caps/branches:32 /sys/bus/event_source/devices/cpu/caps/max_precise:3 /sys/bus/event_source/devices/cpu/caps/pmu_name:skylake Signed-off-by:
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Andi Kleen authored
Only show the Intel format attributes in sysfs when the feature is actually supported with the current model numbers. This allows programs to probe what format attributes are available, and give a sensible error message to users if they are not. This handles near all cases for intel attributes since Nehalem, except the (obscure) case when the model number if known, but PEBS is disabled in PERF_CAPABILITIES. Signed-off-by:
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Andi Kleen authored
Skylake changed the encoding of the PEBS data source field. Some combinations are not available anymore, but some new cases e.g. for L4 cache hit are added. Fix up the conversion table for Skylake, similar as had been done for Nehalem. On Skylake server the encoding for L4 actually means persistent memory. Handle this case too. To properly describe it in the abstracted perf format I had to add some new fields. Since a hit can have only one level add a new field that is an enumeration, not a bit field to describe the level. It can describe any level. Some numbers are also used to describe PMEM and LFB. Also add a new generic remote flag that can be combined with the generic level to signify a remote cache. And there is an extension field for the snoop indication to handle the Forward state. I didn't add a generic flag for hops because it's not needed for Skylake. I changed the existing encodings for older CPUs to also fill in the new level and remote fields. Signed-off-by:
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Andi Kleen authored
Minor cleanup: use an explicit x86_pmu flag to handle the missing Lock / TLB information on Nehalem, instead of always checking the model number for each PEBS sample. Signed-off-by:
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- 21 Jul, 2017 1 commit
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Jiri Olsa authored
We have 2 functions using the same sched_task callback: - PEBS drain for free running counters - LBR save/store Both of them are called from intel_pmu_sched_task() and either of them can be unwillingly triggered when the other one is configured to run. Let's say there's PEBS drain configured in sched_task callback for the event, but in the callback itself (intel_pmu_sched_task()) we will also run the code for LBR save/restore, which we did not ask for, but the code in intel_pmu_sched_task() does not check for that. This can lead to extra cycles in some perf monitoring, like when we monitor PEBS event without LBR data. # perf record --no-timestamp -c 10000 -e cycles:p ./perf bench sched pipe -l 1000000 (We need PEBS, non freq/non timestamp event to enable the sched_task callback) The perf stat of cycles and msr:write_msr for above command before the change: ... Performance counter stats for './perf record --no-timestamp -c 10000 -e cycles:p \ ./perf bench sched pipe -l 1000000' (5 runs): 18,519,557,441 cycles:k 91,195,527 msr:write_msr 29.334476406 seconds time elapsed And after the change: ... Performance counter stats for './perf record --no-timestamp -c 10000 -e cycles:p \ ./perf bench sched pipe -l 1000000' (5 runs): 18,704,973,540 cycles:k 27,184,720 msr:write_msr 16.977875900 seconds time elapsed There's no affect on cycles:k because the sched_task happens with events switched off, however the msr:write_msr tracepoint counter together with almost 50% of time speedup show the improvement. Monitoring LBR event and having extra PEBS drain processing in sched_task callback showed just a little speedup, because the drain function does not do much extra work in case there is no PEBS data. Adding conditions to recognize the configured work that needs to be done in the x86_pmu's sched_task callback. Suggested-by:
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- 18 Jul, 2017 1 commit
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Kan Liang authored
Add perf core PMU support for Intel Goldmont Plus CPU cores: - The init code is based on Goldmont. - There is a new cache event list, based on the Goldmont cache event list. - All four general-purpose performance counters support PEBS. - The first general-purpose performance counter is for reduced skid PEBS mechanism. Using :ppp to indicate the event which want to do reduced skid PEBS. - Goldmont Plus has 4-wide pipeline for Topdown Signed-off-by:
Kan Liang <kan.liang@intel.com> 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: Thomas Gleixner <tglx@linutronix.de> Cc: Vince Weaver <vincent.weaver@maine.edu> Cc: acme@kernel.org Link: http://lkml.kernel.org/r/20170712134423.17766-1-kan.liang@intel.comSigned-off-by:
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- 22 Jun, 2017 1 commit
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Kan Liang authored
Current DTLB load/store miss events (0x608/0x649) only counts 4K,2M and 4M page size. Need to extend the events to support any page size (4K/2M/4M/1G). The complete DTLB load/store miss events are: DTLB_LOAD_MISSES.WALK_COMPLETED 0xe08 DTLB_STORE_MISSES.WALK_COMPLETED 0xe49 Signed-off-by:
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- 26 May, 2017 1 commit
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Sebastian Andrzej Siewior authored
If intel_snb_check_microcode() is invoked via microcode_init -> perf_check_microcode -> intel_snb_check_microcode then get_online_cpus() is invoked nested. This works with the current implementation of get_online_cpus() but prevents converting it to a percpu rwsem. intel_snb_check_microcode() is also invoked from intel_sandybridge_quirk() unprotected. Drop get_online_cpus() from intel_snb_check_microcode() and add it to intel_sandybridge_quirk() so both call sites are protected. Convert *_online_cpus() to the new interfaces while at it. Signed-off-by:
Sebastian Andrzej Siewior <bigeasy@linutronix.de> Signed-off-by:
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- 23 May, 2017 1 commit
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Kan Liang authored
Currently, the SMIs are visible to all performance counters, because many users want to measure everything including SMIs. But in some cases, the SMI cycles should not be counted - for example, to calculate the cost of an SMI itself. So a knob is needed. When setting FREEZE_WHILE_SMM bit in IA32_DEBUGCTL, all performance counters will be effected. There is no way to do per-counter freeze on SMI. So it should not use the per-event interface (e.g. ioctl or event attribute) to set FREEZE_WHILE_SMM bit. Adds sysfs entry /sys/device/cpu/freeze_on_smi to set FREEZE_WHILE_SMM bit in IA32_DEBUGCTL. When set, freezes perfmon and trace messages while in SMM. Value has to be 0 or 1. It will be applied to all processors. Also serialize the entire setting so we don't get multiple concurrent threads trying to update to different values. Signed-off-by:
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- 14 Apr, 2017 1 commit
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Kan Liang authored
Spurious NMIs will be observed with the following command: while :; do perf record -bae "cpu/umask=0x01,event=0xcd,ldlat=0x80/pp" -e "cpu/umask=0x03,event=0x0/" -e "cpu/umask=0x02,event=0x0/" -e cycles,branches,cache-misses -e cache-references -- sleep 10 done The bug was introduced by commit: 8077eca0 ("perf/x86/pebs: Add workaround for broken OVFL status on HSW+") That commit clears the status bits for the counters used for PEBS events, by masking the whole 64 bits pebs_enabled. However, only the low 32 bits of both status and pebs_enabled are reserved for PEBS-able counters. For status bits 32-34 are fixed counter overflow bits. For pebs_enabled bits 32-34 are for PEBS Load Latency. In the test case, the PEBS Load Latency event and fixed counter event could overflow at the same time. The fixed counter overflow bit will be cleared by mistake. Once it is cleared, the fixed counter overflow never be processed, which finally trigger spurious NMI. Correct the PEBS enabled mask by ignoring the non-PEBS bits. Signed-off-by:
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- 16 Mar, 2017 1 commit
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Kan Liang authored
Goldmont supports full Top Down level 1 metrics (FrontendBound, Retiring, Backend Bound and Bad Speculation). It has 3 wide pipeline. Signed-off-by:
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- 17 Jan, 2017 1 commit
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Zhou Chengming authored
The CPU hotplug function intel_pmu_cpu_starting() sets cpu_hw_events.excl_thread_id unconditionally to 1 when the shared exclusive counters data structure is already availabe for the sibling thread. This works during the boot process because the first sibling gets threadid 0 assigned and the second sibling which shares the data structure gets 1. But when the first thread of the core is offlined and onlined again it shares the data structure with the second thread and gets exclusive thread id 1 assigned as well. Prevent this by checking the threadid of the already online thread. [ tglx: Rewrote changelog ] Signed-off-by:
Zhou Chengming <zhouchengming1@huawei.com> Cc: NuoHan Qiao <qiaonuohan@huawei.com> Cc: ak@linux.intel.com Cc: peterz@infradead.org Cc: kan.liang@intel.com Cc: dave.hansen@linux.intel.com Cc: eranian@google.com Cc: qiaonuohan@huawei.com Cc: davidcc@google.com Cc: guohanjun@huawei.com Link: http://lkml.kernel.org/r/1484536871-3131-1-git-send-email-zhouchengming1@huawei.comSigned-off-by:
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- 11 Jan, 2017 1 commit
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Colin King authored
When x86_pmu.num_counters is 32 the shift of the integer constant 1 is exceeding 32bit and therefor undefined behaviour. Fix this by shifting 1ULL instead of 1. Reported-by: CoverityScan CID#1192105 ("Bad bit shift operation") Signed-off-by:Colin Ian King <colin.king@canonical.com> Cc: Andi Kleen <ak@linux.intel.com> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Kan Liang <kan.liang@intel.com> Cc: Stephane Eranian <eranian@google.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Link: http://lkml.kernel.org/r/20170111114310.17928-1-colin.king@canonical.comSigned-off-by:
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- 22 Dec, 2016 1 commit
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Stephane Eranian authored
This patch solves a race condition between PEBS and the PMU handler. In case multiple PEBS events are sampled at the same time, it is possible to have GLOBAL_STATUS bit 62 set indicating PEBS buffer overflow and also seeing at most 3 PEBS counters having their bits set in the status register. This is a sign that there was at least one PEBS record pending at the time of the PMU interrupt. PEBS counters must only be processed via the drain_pebs() calls, and not via the regular sample processing loop coming after that the function, otherwise phony regular samples may be generated in the sampling buffer not marked with the EXACT tag. Another possibility is to have one PEBS event and at least one non-PEBS event whic hoverflows while PEBS has armed. In this case, bit 62 of GLOBAL_STATUS will not be set, yet the overflow status bit for the PEBS counter will be on Skylake. To avoid this problem, we systematically ignore the PEBS-enabled counters from the GLOBAL_STATUS mask and we always process PEBS events via drain_pebs(). The problem manifested itself by having non-exact samples when sampling only PEBS events, i.e., the PERF_SAMPLE_RECORD would not have the EXACT flag set. Note that this problem is only present on Skylake processor. This fix is harmless on older processors. Reported-by:
Stephane Eranian <eranian@google.com> Signed-off-by:
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- 06 Dec, 2016 1 commit
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Peter Zijlstra (Intel) authored
Lukasz reported that perf stat counters overflow handling is broken on KNL/SLM. Both these parts have full_width_write set, and that does indeed have a problem. In order to deal with counter wrap, we must sample the counter at at least half the counter period (see also the sampling theorem) such that we can unambiguously reconstruct the count. However commit: 069e0c3c ("perf/x86/intel: Support full width counting") sets the sampling interval to the full period, not half. Fixing that exposes another issue, in that we must not sign extend the delta value when we shift it right; the counter cannot have decremented after all. With both these issues fixed, counter overflow functions correctly again. Reported-by:
Lukasz Odzioba <lukasz.odzioba@intel.com> Tested-by:
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- 28 Oct, 2016 1 commit
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Imre Palik authored
perf doesn't seem to honour the number of fixed counters specified by CPUID leaf 0xa. It always assumes that Intel CPUs have at least 3 fixed counters. So if some of the fixed counters are masked out by the hypervisor, it still tries to check/set them. This patch makes perf behave nicer when the kernel is running under a hypervisor that doesn't expose all the counters. This patch contains some ideas from Matt Wilson. Signed-off-by:
Imre Palik <imrep@amazon.de> Signed-off-by:
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- 17 Oct, 2016 1 commit
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Piotr Luc authored
Add Knights Mill (KNM) to the list of CPUIDs supported by PMU. Signed-off-by:
Piotr Luc <piotr.luc@intel.com> Reviewed-by:
Dave Hansen <dave.hansen@intel.com> Cc: Andy Lutomirski <luto@kernel.org> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Josh Poimboeuf <jpoimboe@redhat.com> Cc: Linus Torvalds <torvalds@linux-foundation.org> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Thomas Gleixner <tglx@linutronix.de> Link: http://lkml.kernel.org/r/20161012182634.2462-1-piotr.luc@intel.comSigned-off-by:
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- 15 Sep, 2016 1 commit
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Alexander Shishkin authored
At the moment, intel_bts events get disabled from intel PMU's disable callback, which includes event scheduling transactions of said PMU, which have nothing to do with intel_bts events. We do want to keep intel_bts events off inside the PMI handler to avoid filling up their buffer too soon. This patch moves intel_bts enabling/disabling directly to the PMI handler. Reported-by:
Vince Weaver <vincent.weaver@maine.edu> Signed-off-by:
Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Arnaldo Carvalho de Melo <acme@infradead.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 <a.p.zijlstra@chello.nl> Cc: Peter Zijlstra <peterz@infradead.org> Cc: Stephane Eranian <eranian@google.com> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: vince@deater.net Link: http://lkml.kernel.org/r/20160915082233.11065-1-alexander.shishkin@linux.intel.comSigned-off-by:
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- 10 Aug, 2016 1 commit
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Peter Zijlstra authored
Currently perf_sched_cb_{inc,dec}() are called from pmu::{start,stop}(), which has the problem that this can happen from NMI context, this is making it hard to optimize perf_pmu_sched_task(). Furthermore, we really only need this accounting on pmu::{add,del}(), so doing it from pmu::{start,stop}() is doing more work than we really need. Introduce x86_pmu::{add,del}() and wire up the LBR and PEBS. Signed-off-by:
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- 14 Jul, 2016 1 commit
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Thomas Gleixner authored
Replace the perf_notifier() install mechanism, which invokes magically the callback on the current CPU. Convert the hardware specific callbacks which are invoked from the x86 perf core to return proper error codes instead of totally pointless NOTIFY_BAD return values. Signed-off-by:
Anna-Maria Gleixner <anna-maria@linutronix.de> Reviewed-by:
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- 03 Jul, 2016 1 commit
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Stephane Eranian authored
This patch updates the event constraints for non-PEBS mode for Intel Broadwell and Skylake processors. When HT is off, each CPU gets 8 generic counters. However, not all events can be programmed on any of the 8 counters. This patch adds the constraints for the MEM_* events which can only be measured on the bottom 4 counters. The constraints are also valid when HT is off because, then, there are only 4 generic counters and they are the bottom counters. Signed-off-by:
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- 27 Jun, 2016 2 commits
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David Carrillo-Cisneros authored
Intel's SDM states that bits 61:62 in MSR_LAST_BRANCH_FROM_x are the TSX flags for formats with LBR_TSX flags (i.e. LBR_FORMAT_EIP_EFLAGS2). However, when the CPU has TSX support deactivated, bits 61:62 actually behave as follows: - For wrmsr(), bits 61:62 are considered part of the sign extension. - When capturing branches, the LBR hw will always clear bits 61:62. regardless of the sign extension. Therefore, if: 1) LBR has TSX format. 2) CPU has no TSX support enabled. ... then any value passed to wrmsr() must be sign extended to 63 bits and any value from rdmsr() must be converted to have a sign extension of 61 bits, ignoring the values at TSX flags. This bug was masked by the work-around to the Intel's CPU bug: BJ94. "LBR May Contain Incorrect Information When Using FREEZE_LBRS_ON_PMI" in Document Number: 324643-037US. The aforementioned work-around uses hw flags to filter out all kernel branches, limiting LBR callstack to user level execution only. Since user addresses are not sign extended, they do not trigger the wrmsr() bug in MSR_LAST_BRANCH_FROM_x when saved/restored at context switch. To verify the hw bug: $ perf record -b -e cycles sleep 1 $ rdmsr -p 0 0x680 0x1fffffffb0b9b0cc $ wrmsr -p 0 0x680 0x1fffffffb0b9b0cc write(): Input/output error The quirk for LBR_FROM_ MSRs is required before calls to wrmsrl() and after rdmsrl(). This patch introduces it for wrmsrl()'s done for testing LBR support. Future patch in series adds the quirk for context switch, that would be required if LBR callstack is to be enabled for ring 0. Signed-off-by:David Carrillo-Cisneros <davidcc@google.com> Signed-off-by:
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David Carrillo-Cisneros authored
The following commit: 338b522c ("perf/x86/intel: Protect LBR and extra_regs against KVM lying") added an additional test to LBR support detection that is performed after printing the LBR support statement to dmesg. Move the LBR support output after the very last test, to make sure we print the true status of LBR support. Signed-off-by:
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- 08 Jun, 2016 1 commit
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Dave Hansen authored
Use the new model number macros instead of spelling things out in the comments. Note that this is missing a Nehalem model that is mentioned in intel_idle which is fixed up in a later patch. The resulting binary (arch/x86/events/intel/core.o) is exactly the same with and without this patch modulo some harmless changes to restoring %esi in the return path of functions, even those untouched by this patch. Signed-off-by:
Dave Hansen <dave.hansen@linux.intel.com> Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com> Cc: Andy Lutomirski <luto@amacapital.net> Cc: Arnaldo Carvalho de Melo <acme@redhat.com> Cc: Borislav Petkov <bp@alien8.de> Cc: Brian Gerst <brgerst@gmail.com> Cc: Dave Hansen <dave@sr71.net> Cc: Denys Vlasenko <dvlasenk@redhat.com> Cc: H. Peter Anvin <hpa@zytor.com> Cc: Jiri Olsa <jolsa@redhat.com> Cc: Kan Liang <kan.liang@intel.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: jacob.jun.pan@intel.com Link: http://lkml.kernel.org/r/20160603001929.C5F1C079@viggo.jf.intel.comSigned-off-by:
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- 03 Jun, 2016 5 commits
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Andi Kleen authored
Now that we have topology_max_smt_threads() use it to detect the HT workarounds for older CPUs. Signed-off-by:
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Andi Kleen authored
Add topdown event declarations to Silvermont / Airmont. These cores do not support the full Top Down metrics, but an useful subset (FrontendBound, Retiring, Backend Bound/Bad Speculation). The perf stat tool automatically handles the missing events and combines the available metrics. Signed-off-by:
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Andi Kleen authored
Add declarations for the events needed for topdown to the Intel big core CPUs starting with Sandy Bridge. We need to report different values if HyperThreading is on or off. The only thing this patch does is to export some events in sysfs. topdown level 1 uses a set of abstracted metrics which are generic to out of order CPU cores (although some CPUs may not implement all of them): topdown-total-slots Available slots in the pipeline topdown-slots-issued Slots issued into the pipeline topdown-slots-retired Slots successfully retired topdown-fetch-bubbles Pipeline gaps in the frontend topdown-recovery-bubbles Pipeline gaps during recovery from misspeculation A slot is a single operation in the CPU pipe line. These metrics then allow to compute four useful metrics: FrontendBound, BackendBound, Retiring, BadSpeculation. The formulas to compute the metrics are generic, they only change based on the availability on the abstracted input values. The kernel declares the events supported by the current CPU and their scaling factors (such as the pipeline width) and perf stat then computes the formulas based on the available metrics. This is similar how existing perf metrics, such as TSC metrics or IPC, are implemented. This abstracts all CPU pipe line specific knowledge in the kernel driver, but still avoids the need for larger scale perf interface changes. For HyperThreading the any bit is needed to get accurate values when both threads are executing. This implies that the events can only be collected as root or with perf_event_paranoid=-1 for now. The basic scheme is based on the following paper: Yasin, A Top Down Method for Performance analysis and Counter architecture ISPASS14 (pdf available via google) Signed-off-by:
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Lukasz Odzioba authored
Due to change in register definition we need to update OCR mask: MSR_OFFCORE_RESP0 reserved bits: 3,4,18,29,30,33,34, 8,11,14 MSR_OFFCORE_RESP1 reserved bits: 3,4,18,29,30,33,34, 38 Reported-by:
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Lukasz Odzioba authored
Add the 'static' keyword to intel_bdw_event_constraints[], snb_events_attrs[], nhm_events_attrs[] and intel_skl_event_constraints arrays[], because they are only used locally. Signed-off-by:
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