Commit Graph

737 Commits

Author SHA1 Message Date
Kan Liang
c301b1d80e perf/x86/intel/lbr: Add a function pointer for LBR read
The method to read Architectural LBRs is different from previous
model-specific LBR. Perf has to implement a different function.

A function pointer for LBR read is introduced. Perf should initialize
the corresponding function at boot time, and avoid checking lbr_format
at run time.

The current 64-bit LBR read function is set as default.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593780569-62993-4-git-send-email-kan.liang@linux.intel.com
2020-07-08 11:38:51 +02:00
Kan Liang
9f354a726c perf/x86/intel/lbr: Add a function pointer for LBR reset
The method to reset Architectural LBRs is different from previous
model-specific LBR. Perf has to implement a different function.

A function pointer is introduced for LBR reset. The enum of
LBR_FORMAT_* is also moved to perf_event.h. Perf should initialize the
corresponding functions at boot time, and avoid checking lbr_format at
run time.

The current 64-bit LBR reset function is set as default.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1593780569-62993-3-git-send-email-kan.liang@linux.intel.com
2020-07-08 11:38:51 +02:00
Peter Zijlstra
78c2141b65 Merge branch 'perf/vlbr' 2020-07-02 15:51:48 +02:00
Like Xu
e1ad1ac2de perf/x86: Keep LBR records unchanged in host context for guest usage
When a guest wants to use the LBR registers, its hypervisor creates a guest
LBR event and let host perf schedules it. The LBR records msrs are
accessible to the guest when its guest LBR event is scheduled on
by the perf subsystem.

Before scheduling this event out, we should avoid host changes on
IA32_DEBUGCTLMSR or LBR_SELECT. Otherwise, some unexpected branch
operations may interfere with guest behavior, pollute LBR records, and even
cause host branches leakage. In addition, the read operation
on host is also avoidable.

To ensure that guest LBR records are not lost during the context switch,
the guest LBR event would enable the callstack mode which could
save/restore guest unread LBR records with the help of
intel_pmu_lbr_sched_task() naturally.

However, the guest LBR_SELECT may changes for its own use and the host
LBR event doesn't save/restore it. To ensure that we doesn't lost the guest
LBR_SELECT value when the guest LBR event is running, the vlbr_constraint
is bound up with a new constraint flag PERF_X86_EVENT_LBR_SELECT.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200514083054.62538-6-like.xu@linux.intel.com
2020-07-02 15:51:46 +02:00
Like Xu
097e4311cd perf/x86: Add constraint to create guest LBR event without hw counter
The hypervisor may request the perf subsystem to schedule a time window
to directly access the LBR records msrs for its own use. Normally, it would
create a guest LBR event with callstack mode enabled, which is scheduled
along with other ordinary LBR events on the host but in an exclusive way.

To avoid wasting a counter for the guest LBR event, the perf tracks its
hw->idx via INTEL_PMC_IDX_FIXED_VLBR and assigns it with a fake VLBR
counter with the help of new vlbr_constraint. As with the BTS event,
there is actually no hardware counter assigned for the guest LBR event.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200514083054.62538-5-like.xu@linux.intel.com
2020-07-02 15:51:46 +02:00
Like Xu
b2d6504761 perf/x86/lbr: Add interface to get LBR information
The LBR records msrs are model specific. The perf subsystem has already
obtained the base addresses of LBR records based on the cpu model.

Therefore, an interface is added to allow callers outside the perf
subsystem to obtain these LBR information. It's useful for hypervisors
to emulate the LBR feature for guests with less code.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200613080958.132489-4-like.xu@linux.intel.com
2020-07-02 15:51:46 +02:00
Like Xu
027440b5d4 perf/x86/core: Refactor hw->idx checks and cleanup
For intel_pmu_en/disable_event(), reorder the branches checks for hw->idx
and make them sorted by probability: gp,fixed,bts,others.

Clean up the x86_assign_hw_event() by converting multiple if-else
statements to a switch statement.

To skip x86_perf_event_update() and x86_perf_event_set_period(),
it's generic to replace "idx == INTEL_PMC_IDX_FIXED_BTS" check with
'!hwc->event_base' because that should be 0 for all non-gp/fixed cases.

Wrap related bit operations into intel_set/clear_masks() and make the main
path more cleaner and readable.

No functional changes.

Signed-off-by: Like Xu <like.xu@linux.intel.com>
Original-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200613080958.132489-3-like.xu@linux.intel.com
2020-07-02 15:51:46 +02:00
Wei Wang
3cb9d5464c perf/x86: Fix variable types for LBR registers
The MSR variable type can be 'unsigned int', which uses less memory than
the longer 'unsigned long'. Fix 'struct x86_pmu' for that. The lbr_nr won't
be a negative number, so make it 'unsigned int' as well.

Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Wei Wang <wei.w.wang@intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200613080958.132489-2-like.xu@linux.intel.com
2020-07-02 15:51:45 +02:00
Linus Torvalds
ae71d4bf00 A single Kbuild dependency fix.
Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-urgent-2020-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf fix from Ingo Molnar:
 "A single Kbuild dependency fix"

* tag 'perf-urgent-2020-06-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  perf/x86/rapl: Fix RAPL config variable bug
2020-06-28 11:58:14 -07:00
Roman Sudarikov
bb42b3d397 perf/x86/intel/uncore: Expose an Uncore unit to IIO PMON mapping
Current version supports a server line starting Intel® Xeon® Processor
Scalable Family and introduces mapping for IIO Uncore units only.
Other units can be added on demand.

IIO stack to PMON mapping is exposed through:
    /sys/devices/uncore_iio_<pmu_idx>/dieX
    where dieX is file which holds "Segment:Root Bus" for PCIe root port,
    which can be monitored by that IIO PMON block.

Details are explained in Documentation/ABI/testing/sysfs-devices-mapping

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Signed-off-by: Roman Sudarikov <roman.sudarikov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/20200601083543.30011-4-alexander.antonov@linux.intel.com
2020-06-15 14:09:51 +02:00
Roman Sudarikov
36b533bc5e perf/x86/intel/uncore: Wrap the max dies calculation into an accessor
The accessor to return number of dies on the platform.

Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Signed-off-by: Roman Sudarikov <roman.sudarikov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/20200601083543.30011-3-alexander.antonov@linux.intel.com
2020-06-15 14:09:51 +02:00
Roman Sudarikov
19a3981981 perf/x86/intel/uncore: Expose an Uncore unit to PMON mapping
Each Uncore unit type, by its nature, can be mapped to its own context -
which platform component each PMON block of that type is supposed to
monitor.

Intel® Xeon® Scalable processor family (code name Skylake-SP) makes
significant changes in the integrated I/O (IIO) architecture. The new
solution introduces IIO stacks which are responsible for managing traffic
between the PCIe domain and the Mesh domain. Each IIO stack has its own
PMON block and can handle either DMI port, x16 PCIe root port, MCP-Link
or various built-in accelerators. IIO PMON blocks allow concurrent
monitoring of I/O flows up to 4 x4 bifurcation within each IIO stack.

Software is supposed to program required perf counters within each IIO
stack and gather performance data. The tricky thing here is that IIO PMON
reports data per IIO stack but users have no idea what IIO stacks are -
they only know devices which are connected to the platform.

Understanding IIO stack concept to find which IIO stack that particular
IO device is connected to, or to identify an IIO PMON block to program
for monitoring specific IIO stack assumes a lot of implicit knowledge
about given Intel server platform architecture.

Usage example:
    ls /sys/devices/uncore_<type>_<pmu_idx>/die*

Signed-off-by: Alexander Antonov <alexander.antonov@linux.intel.com>
Signed-off-by: Roman Sudarikov <roman.sudarikov@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Kan Liang <kan.liang@linux.intel.com>
Reviewed-by: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Link: https://lkml.kernel.org/r/20200601083543.30011-2-alexander.antonov@linux.intel.com
2020-06-15 14:09:51 +02:00
Kan Liang
f01719730b perf/x86/intel/uncore: Validate MMIO address before accessing
An oops will be triggered, if perf tries to access an invalid address
which exceeds the mapped area.

Check the address before the actual access to MMIO sapce of an uncore
unit.

Suggested-by: David Laight <David.Laight@ACULAB.COM>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1590679169-61823-3-git-send-email-kan.liang@linux.intel.com
2020-06-15 14:09:50 +02:00
Kan Liang
1b94d31de4 perf/x86/intel/uncore: Record the size of mapped area
Perf cannot validate an address before the actual access to MMIO space
of some uncore units, e.g. IMC on TGL. Accessing an invalid address,
which exceeds mapped area, can trigger oops.

Perf never records the size of mapped area. Generic functions, e.g.
uncore_mmio_read_counter(), cannot get the correct size for address
validation.

Add mmio_map_size in intel_uncore_type to record the size of mapped
area. Print warning message if ioremap fails.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1590679169-61823-2-git-send-email-kan.liang@linux.intel.com
2020-06-15 14:09:50 +02:00
Kan Liang
2af834f1fa perf/x86/intel/uncore: Fix oops when counting IMC uncore events on some TGL
When counting IMC uncore events on some TGL machines, an oops will be
triggered.
  [ 393.101262] BUG: unable to handle page fault for address:
  ffffb45200e15858
  [ 393.101269] #PF: supervisor read access in kernel mode
  [ 393.101271] #PF: error_code(0x0000) - not-present page

Current perf uncore driver still use the IMC MAP SIZE inherited from
SNB, which is 0x6000.
However, the offset of IMC uncore counters is larger than 0x6000,
e.g. 0xd8a0.

Enlarge the IMC MAP SIZE for TGL to 0xe000.

Fixes: fdb6482244 ("perf/x86: Add Intel Tiger Lake uncore support")
Reported-by: Ammy Yi <ammy.yi@intel.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Ammy Yi <ammy.yi@intel.com>
Tested-by: Chao Qin <chao.qin@intel.com>
Link: https://lkml.kernel.org/r/1590679169-61823-1-git-send-email-kan.liang@linux.intel.com
2020-06-15 14:09:50 +02:00
Kan Liang
bb85429a9b perf/x86/intel/uncore: Add Comet Lake support
The uncore subsystem on Comet Lake is similar to Sky Lake.
The only difference is the new PCI IDs for IMC.

Share the perf code with Sky Lake.
Add new PCI IDs in the table.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1589915905-55870-1-git-send-email-kan.liang@linux.intel.com
2020-06-15 14:09:47 +02:00
Masahiro Yamada
a7f7f6248d treewide: replace '---help---' in Kconfig files with 'help'
Since commit 84af7a6194 ("checkpatch: kconfig: prefer 'help' over
'---help---'"), the number of '---help---' has been gradually
decreasing, but there are still more than 2400 instances.

This commit finishes the conversion. While I touched the lines,
I also fixed the indentation.

There are a variety of indentation styles found.

  a) 4 spaces + '---help---'
  b) 7 spaces + '---help---'
  c) 8 spaces + '---help---'
  d) 1 space + 1 tab + '---help---'
  e) 1 tab + '---help---'    (correct indentation)
  f) 1 tab + 1 space + '---help---'
  g) 1 tab + 2 spaces + '---help---'

In order to convert all of them to 1 tab + 'help', I ran the
following commend:

  $ find . -name 'Kconfig*' | xargs sed -i 's/^[[:space:]]*---help---/\thelp/'

Signed-off-by: Masahiro Yamada <masahiroy@kernel.org>
2020-06-14 01:57:21 +09:00
Michel Lespinasse
c1e8d7c6a7 mmap locking API: convert mmap_sem comments
Convert comments that reference mmap_sem to reference mmap_lock instead.

[akpm@linux-foundation.org: fix up linux-next leftovers]
[akpm@linux-foundation.org: s/lockaphore/lock/, per Vlastimil]
[akpm@linux-foundation.org: more linux-next fixups, per Michel]

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-13-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Michel Lespinasse
42fc541404 mmap locking API: add mmap_assert_locked() and mmap_assert_write_locked()
Add new APIs to assert that mmap_sem is held.

Using this instead of rwsem_is_locked and lockdep_assert_held[_write]
makes the assertions more tolerant of future changes to the lock type.

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Laurent Dufour <ldufour@linux.ibm.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-10-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
2020-06-09 09:39:14 -07:00
Linus Torvalds
f4dd60a3d4 Misc changes:
- Unexport various PAT primitives
 
  - Unexport per-CPU tlbstate
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'x86-mm-2020-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull x86 mm updates from Ingo Molnar:
 "Misc changes:

   - Unexport various PAT primitives

   - Unexport per-CPU tlbstate and uninline TLB helpers"

* tag 'x86-mm-2020-06-05' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (23 commits)
  x86/tlb/uv: Add a forward declaration for struct flush_tlb_info
  x86/cpu: Export native_write_cr4() only when CONFIG_LKTDM=m
  x86/tlb: Restrict access to tlbstate
  xen/privcmd: Remove unneeded asm/tlb.h include
  x86/tlb: Move PCID helpers where they are used
  x86/tlb: Uninline nmi_uaccess_okay()
  x86/tlb: Move cr4_set_bits_and_update_boot() to the usage site
  x86/tlb: Move paravirt_tlb_remove_table() to the usage site
  x86/tlb: Move __flush_tlb_all() out of line
  x86/tlb: Move flush_tlb_others() out of line
  x86/tlb: Move __flush_tlb_one_kernel() out of line
  x86/tlb: Move __flush_tlb_one_user() out of line
  x86/tlb: Move __flush_tlb_global() out of line
  x86/tlb: Move __flush_tlb() out of line
  x86/alternatives: Move temporary_mm helpers into C
  x86/cr4: Sanitize CR4.PCE update
  x86/cpu: Uninline CR4 accessors
  x86/tlb: Uninline __get_current_cr3_fast()
  x86/mm: Use pgprotval_t in protval_4k_2_large() and protval_large_2_4k()
  x86/mm: Unexport __cachemode2pte_tbl
  ...
2020-06-05 11:18:53 -07:00
Stephane Eranian
16accae3d9 perf/x86/rapl: Fix RAPL config variable bug
This patch fixes a bug introduced by:

  fd3ae1e158 ("perf/x86/rapl: Move RAPL support to common x86 code")

The Kconfig variable name was wrong. It was missing the CONFIG_ prefix.

Signed-off-by: Stephane Eranian <eraniangoogle.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Kim Phillips <kim.phillips@amd.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20200528201614.250182-1-eranian@google.com
2020-06-02 11:52:56 +02:00
Stephane Eranian
5cde265384 perf/x86/rapl: Add AMD Fam17h RAPL support
This patch enables AMD Fam17h RAPL support for the Package level metric.
The support is as per AMD Fam17h Model31h (Zen2) and model 00-ffh (Zen1) PPR.

The same output is available via the energy-pkg pseudo event:

  $ perf stat -a -I 1000 --per-socket -e power/energy-pkg/

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200527224659.206129-6-eranian@google.com
2020-05-28 07:58:56 +02:00
Stephane Eranian
4c953f8794 perf/x86/rapl: Make perf_probe_msr() more robust and flexible
This patch modifies perf_probe_msr() by allowing passing of
struct perf_msr array where some entries are not populated, i.e.,
they have either an msr address of 0 or no attribute_group pointer.
This helps with certain call paths, e.g., RAPL.

In case the grp is NULL, the default sysfs visibility rule
applies which is to make the group visible. Without the patch,
you would get a kernel crash with a NULL group.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200527224659.206129-5-eranian@google.com
2020-05-28 07:58:55 +02:00
Stephane Eranian
2a3e3f73a2 perf/x86/rapl: Flip logic on default events visibility
This patch modifies the default visibility of the attribute_group
for each RAPL event. By default if the grp.is_visible field is NULL,
sysfs considers that it must display the attribute group.
If the field is not NULL (callback function), then the return value
of the callback determines the visibility (0 = not visible). The RAPL
attribute groups had the field set to NULL, meaning that unless they
failed the probing from perf_msr_probe(), they would be visible. We want
to avoid having to specify attribute groups that are not supported by the HW
in the rapl_msrs[] array, they don't have an MSR address to begin with.

Therefore, we intialize the visible field of all RAPL attribute groups
to a callback that returns 0. If the RAPL msr goes through probing
and succeeds the is_visible field will be set back to NULL (visible).
If the probing fails the field is set to a callback that return 0 (not visible).

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200527224659.206129-4-eranian@google.com
2020-05-28 07:58:55 +02:00
Stephane Eranian
5c95c68949 perf/x86/rapl: Refactor to share the RAPL code between Intel and AMD CPUs
This patch modifies the rapl_model struct to include architecture specific
knowledge in this previously Intel specific structure, and in particular
it adds the MSR for POWER_UNIT and the rapl_msrs array.

No functional changes.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200527224659.206129-3-eranian@google.com
2020-05-28 07:58:55 +02:00
Stephane Eranian
fd3ae1e158 perf/x86/rapl: Move RAPL support to common x86 code
To prepare for support of both Intel and AMD RAPL.

As per the AMD PPR, Fam17h support Package RAPL counters to monitor power usage.
The RAPL counter operates as with Intel RAPL, and as such it is beneficial
to share the code.

No change in functionality.

Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lore.kernel.org/r/20200527224659.206129-2-eranian@google.com
2020-05-28 07:58:55 +02:00
Ingo Molnar
0bffedbce9 Linux 5.7-rc7
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Merge tag 'v5.7-rc7' into perf/core, to pick up fixes

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-05-28 07:58:12 +02:00
Gustavo A. R. Silva
8ac7571a8c perf/x86: Replace zero-length array with flexible-array
The current codebase makes use of the zero-length array language
extension to the C90 standard, but the preferred mechanism to declare
variable-length types such as these ones is a flexible array member[1][2],
introduced in C99:

struct foo {
        int stuff;
        struct boo array[];
};

By making use of the mechanism above, we will get a compiler warning
in case the flexible array does not occur last in the structure, which
will help us prevent some kind of undefined behavior bugs from being
inadvertently introduced[3] to the codebase from now on.

Also, notice that, dynamic memory allocations won't be affected by
this change:

"Flexible array members have incomplete type, and so the sizeof operator
may not be applied. As a quirk of the original implementation of
zero-length arrays, sizeof evaluates to zero."[1]

sizeof(flexible-array-member) triggers a warning because flexible array
members have incomplete type[1]. There are some instances of code in
which the sizeof operator is being incorrectly/erroneously applied to
zero-length arrays and the result is zero. Such instances may be hiding
some bugs. So, this work (flexible-array member conversions) will also
help to get completely rid of those sorts of issues.

This issue was found with the help of Coccinelle.

[1] https://gcc.gnu.org/onlinedocs/gcc/Zero-Length.html
[2] https://github.com/KSPP/linux/issues/21
[3] commit 7649773293 ("cxgb3/l2t: Fix undefined behaviour")

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200511200911.GA13149@embeddedor
2020-05-19 20:34:16 +02:00
Kan Liang
0813c40556 perf/x86/intel: Add more available bits for OFFCORE_RESPONSE of Intel Tremont
The mask in the extra_regs for Intel Tremont need to be extended to
allow more defined bits.

"Outstanding Requests" (bit 63) is only available on MSR_OFFCORE_RSP0;

Fixes: 6daeb8737f ("perf/x86/intel: Add Tremont core PMU support")
Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Cc: stable@vger.kernel.org
Link: https://lkml.kernel.org/r/20200501125442.7030-1-kan.liang@linux.intel.com
2020-05-19 20:34:16 +02:00
Kan Liang
f649fc2eef perf/x86/rapl: Add Ice Lake RAPL support
Enable RAPL support for Intel Ice Lake X and Ice Lake D.

For RAPL support, it is identical to Sky Lake X.

Reported-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1588857258-38213-1-git-send-email-kan.liang@linux.intel.com
2020-05-19 20:34:16 +02:00
Paul Gortmaker
4bd30106dd perf/x86/intel/pt: Drop pointless NULL assignment.
Only a few lines below this removed line is this:

  attrs = kzalloc(size, GFP_KERNEL);

and since there is no code path where this could be avoided, the
NULL assignment is a pointless relic of history and can be removed.

Signed-off-by: Paul Gortmaker <paul.gortmaker@windriver.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200408235216.108980-1-paul.gortmaker@windriver.com
2020-04-30 20:14:36 +02:00
CodyYao-oc
3a4ac121c2 x86/perf: Add hardware performance events support for Zhaoxin CPU.
Zhaoxin CPU has provided facilities for monitoring performance
via PMU (Performance Monitor Unit), but the functionality is unused so far.
Therefore, add support for zhaoxin pmu to make performance related
hardware events available.

The PMU is mostly an Intel Architectural PerfMon-v2 with a novel
errata for the ZXC line. It supports the following events:

  -----------------------------------------------------------------------------------------------------------------------------------
  Event                      | Event  | Umask |          Description
			     | Select |       |
  -----------------------------------------------------------------------------------------------------------------------------------
  cpu-cycles                 |  82h   |  00h  | unhalt core clock
  instructions               |  00h   |  00h  | number of instructions at retirement.
  cache-references           |  15h   |  05h  | number of fillq pushs at the current cycle.
  cache-misses               |  1ah   |  05h  | number of l2 miss pushed by fillq.
  branch-instructions        |  28h   |  00h  | counts the number of branch instructions retired.
  branch-misses              |  29h   |  00h  | mispredicted branch instructions at retirement.
  bus-cycles                 |  83h   |  00h  | unhalt bus clock
  stalled-cycles-frontend    |  01h   |  01h  | Increments each cycle the # of Uops issued by the RAT to RS.
  stalled-cycles-backend     |  0fh   |  04h  | RS0/1/2/3/45 empty
  L1-dcache-loads            |  68h   |  05h  | number of retire/commit load.
  L1-dcache-load-misses      |  4bh   |  05h  | retired load uops whose data source followed an L1 miss.
  L1-dcache-stores           |  69h   |  06h  | number of retire/commit Store,no LEA
  L1-dcache-store-misses     |  62h   |  05h  | cache lines in M state evicted out of L1D due to Snoop HitM or dirty line replacement.
  L1-icache-loads            |  00h   |  03h  | number of l1i cache access for valid normal fetch,including un-cacheable access.
  L1-icache-load-misses      |  01h   |  03h  | number of l1i cache miss for valid normal fetch,including un-cacheable miss.
  L1-icache-prefetches       |  0ah   |  03h  | number of prefetch.
  L1-icache-prefetch-misses  |  0bh   |  03h  | number of prefetch miss.
  dTLB-loads                 |  68h   |  05h  | number of retire/commit load
  dTLB-load-misses           |  2ch   |  05h  | number of load operations miss all level tlbs and cause a tablewalk.
  dTLB-stores                |  69h   |  06h  | number of retire/commit Store,no LEA
  dTLB-store-misses          |  30h   |  05h  | number of store operations miss all level tlbs and cause a tablewalk.
  dTLB-prefetches            |  64h   |  05h  | number of hardware pte prefetch requests dispatched out of the prefetch FIFO.
  dTLB-prefetch-misses       |  65h   |  05h  | number of hardware pte prefetch requests miss the l1d data cache.
  iTLB-load                  |  00h   |  00h  | actually counter instructions.
  iTLB-load-misses           |  34h   |  05h  | number of code operations miss all level tlbs and cause a tablewalk.
  -----------------------------------------------------------------------------------------------------------------------------------

Reported-by: kbuild test robot <lkp@intel.com>
Signed-off-by: CodyYao-oc <CodyYao-oc@zhaoxin.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1586747669-4827-1-git-send-email-CodyYao-oc@zhaoxin.com
2020-04-30 20:14:35 +02:00
Thomas Gleixner
cb2a02355b x86/cr4: Sanitize CR4.PCE update
load_mm_cr4_irqsoff() is really a strange name for a function which has
only one purpose: Update the CR4.PCE bit depending on the perf state.

Rename it to update_cr4_pce_mm(), move it into the tlb code and provide a
function which can be invoked by the perf smp function calls.

Another step to remove exposure of cpu_tlbstate.

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Alexandre Chartre <alexandre.chartre@oracle.com>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20200421092559.049499158@linutronix.de
2020-04-24 19:01:17 +02:00
Harry Pan
5b16ef2e43 perf/x86/cstate: Add Jasper Lake CPU support
The Jasper Lake processor is Tremont microarchitecture, reuse the
glm_cstates table of Goldmont and Goldmont Plus to enable the C-states
residency profiling.

Signed-off-by: Harry Pan <harry.pan@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Link: https://lkml.kernel.org/r/20200402190658.1.Ic02e891daac41303aed1f2fc6c64f6110edd27bd@changeid
2020-04-22 21:43:12 +02:00
Kan Liang
2b3b76b5ec perf/x86/intel/uncore: Add Ice Lake server uncore support
The uncore subsystem in Ice Lake server is similar to previous server.
There are some differences in config register encoding and pci device
IDs. The uncore PMON units in Ice Lake server include Ubox, Chabox, IIO,
IRP, M2PCIE, PCU, M2M, PCIE3 and IMC.

 - For CHA, filter 1 register has been removed. The filter 0 register can
   be used by and of CHA events to be filterd by Thread/Core-ID. To do
   so, the control register's tid_en bit must be set to 1.
 - For IIO, there are some changes on event constraints. The MSR address
   and MSR offsets among counters are also changed.
 - For IRP, the MSR address and MSR offsets among counters are changed.
 - For M2PCIE, the counters are accessed by MSR now. Add new MSR address
   and MSR offsets. Change event constraints.
 - To determine the number of CHAs, have to read CAPID6(Low) and CAPID7
   (High) now.
 - For M2M, update the PCICFG address and Device ID.
 - For UPI, update the PCICFG address, Device ID and counter address.
 - For M3UPI, update the PCICFG address, Device ID, counter address and
   event constraints.
 - For IMC, update the formular to calculate MMIO BAR address, which is
   MMIO_BASE + specific MEM_BAR offset.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/1585842411-150452-1-git-send-email-kan.liang@linux.intel.com
2020-04-08 11:33:46 +02:00
Linus Torvalds
fdf5563a72 Merge branch 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull x86 cleanups from Ingo Molnar:
 "This topic tree contains more commits than usual:

   - most of it are uaccess cleanups/reorganization by Al

   - there's a bunch of prototype declaration (--Wmissing-prototypes)
     cleanups

   - misc other cleanups all around the map"

* 'x86-cleanups-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (36 commits)
  x86/mm/set_memory: Fix -Wmissing-prototypes warnings
  x86/efi: Add a prototype for efi_arch_mem_reserve()
  x86/mm: Mark setup_emu2phys_nid() static
  x86/jump_label: Move 'inline' keyword placement
  x86/platform/uv: Add a missing prototype for uv_bau_message_interrupt()
  kill uaccess_try()
  x86: unsafe_put-style macro for sigmask
  x86: x32_setup_rt_frame(): consolidate uaccess areas
  x86: __setup_rt_frame(): consolidate uaccess areas
  x86: __setup_frame(): consolidate uaccess areas
  x86: setup_sigcontext(): list user_access_{begin,end}() into callers
  x86: get rid of put_user_try in __setup_rt_frame() (both 32bit and 64bit)
  x86: ia32_setup_rt_frame(): consolidate uaccess areas
  x86: ia32_setup_frame(): consolidate uaccess areas
  x86: ia32_setup_sigcontext(): lift user_access_{begin,end}() into the callers
  x86/alternatives: Mark text_poke_loc_init() static
  x86/cpu: Fix a -Wmissing-prototypes warning for init_ia32_feat_ctl()
  x86/mm: Drop pud_mknotpresent()
  x86: Replace setup_irq() by request_irq()
  x86/configs: Slightly reduce defconfigs
  ...
2020-03-31 11:04:05 -07:00
Ingo Molnar
629b3df7ec Merge branch 'x86/cpu' into perf/core, to resolve conflict
Conflicts:
	arch/x86/events/intel/uncore.c

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-25 15:20:44 +01:00
Thomas Gleixner
ef37219ab8 x86/perf/events: Convert to new CPU match macros
The new macro set has a consistent namespace and uses C99 initializers
instead of the grufty C89 ones.

Get rid the of the local macro wrappers for consistency.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Link: https://lkml.kernel.org/r/20200320131509.029267418@linutronix.de
2020-03-24 21:22:28 +01:00
Kan Liang
3442a9ecb8 perf/x86/intel/uncore: Factor out __snr_uncore_mmio_init_box
The IMC uncore unit in Ice Lake server can only be accessed by MMIO,
which is similar as Snow Ridge.
Factor out __snr_uncore_mmio_init_box which can be shared with Ice Lake
server in the following patch.

No functional changes.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1584470314-46657-2-git-send-email-kan.liang@linux.intel.com
2020-03-20 13:06:23 +01:00
Kan Liang
bc88a2fe21 perf/x86/intel/uncore: Add box_offsets for free-running counters
The offset between uncore boxes of free-running counters varies, e.g.
IIO free-running counters on Ice Lake server.

Add box_offsets, an array of offsets between adjacent uncore boxes.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/1584470314-46657-1-git-send-email-kan.liang@linux.intel.com
2020-03-20 13:06:23 +01:00
Ingo Molnar
409e1a3140 Merge branch 'perf/urgent' into perf/core, to pick up fixes
Signed-off-by: Ingo Molnar <mingo@kernel.org>
2020-03-19 15:01:45 +01:00
Kim Phillips
e48667b865 perf/amd/uncore: Add support for Family 19h L3 PMU
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
2020-03-17 13:01:03 +01:00
Kim Phillips
9689dbbeae perf/amd/uncore: Make L3 thread mask code more readable
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
2020-03-17 13:00:49 +01:00
Kim Phillips
4dcc3df825 perf/amd/uncore: Prepare L3 thread mask code for Family 19h
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
2020-03-17 13:00:29 +01:00
Kim Phillips
f967140dfb perf/amd/uncore: Replace manual sampling check with CAP_NO_INTERRUPT flag
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
2020-03-12 14:08:50 +01:00
Al Viro
c8e3dd8660 x86 user stack frame reads: switch to explicit __get_user()
rather than relying upon the magic in raw_copy_from_user()

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
2020-02-15 17:26:26 -05:00
Kan Liang
fdb6482244 perf/x86: Add Intel Tiger Lake uncore support
For MSR type of uncore units, there is no difference between Ice Lake
and Tiger Lake. Share the same code with Ice Lake.

Tiger Lake has two MCs. Both of them are located at 0:0:0. The BAR
offset is still 0x48. The offset of the two MCs is 0x10000.
Each MC has three counters to count every read/write/total issued by the
Memory Controller to DRAM. The counters can be accessed by MMIO.
They are free-running counters.

The offset of counters are different for TIGERLAKE_L and TIGERLAKE.
Add separated mmio_init() functions.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Andi Kleen <ak@linux.intel.com>
Link: https://lkml.kernel.org/r/20200206161527.3529-1-kan.liang@linux.intel.com
2020-02-11 13:23:49 +01:00
Kan Liang
db278b90c3 perf/x86/intel: Output LBR TOS information correctly
For Intel LBR, the LBR Top-of-Stack (TOS) information is the HW index of
raw branch record for the most recent branch.

For non-adaptive PEBS and non-PEBS, the TOS information can be directly
retrieved from TOS MSR read in intel_pmu_lbr_read().

For adaptive PEBS, the LBR information stored in PEBS record doesn't
include the TOS information. For single PEBS, TOS can be directly read
from MSR, because the PMI is triggered immediately after PEBS is
written. TOS MSR is still unchanged.
For large PEBS, TOS MSR has stale value. Set -1ULL to indicate that the
TOS information is not available.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200127165355.27495-3-kan.liang@linux.intel.com
2020-02-11 13:23:49 +01:00
Kan Liang
bbfd5e4fab perf/core: Add new branch sample type for HW index of raw branch records
The low level index is the index in the underlying hardware buffer of
the most recently captured taken branch which is always saved in
branch_entries[0]. It is very useful for reconstructing the call stack.
For example, in Intel LBR call stack mode, the depth of reconstructed
LBR call stack limits to the number of LBR registers. With the low level
index information, perf tool may stitch the stacks of two samples. The
reconstructed LBR call stack can break the HW limitation.

Add a new branch sample type to retrieve low level index of raw branch
records. The low level index is between -1 (unknown) and max depth which
can be retrieved in /sys/devices/cpu/caps/branches.

Only when the new branch sample type is set, the low level index
information is dumped into the PERF_SAMPLE_BRANCH_STACK output.
Perf tool should check the attr.branch_sample_type, and apply the
corresponding format for PERF_SAMPLE_BRANCH_STACK samples.
Otherwise, some user case may be broken. For example, users may parse a
perf.data, which include the new branch sample type, with an old version
perf tool (without the check). Users probably get incorrect information
without any warning.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200127165355.27495-2-kan.liang@linux.intel.com
2020-02-11 13:23:49 +01:00
Kan Liang
6c1c07b33e perf/x86/intel: Avoid unnecessary PEBS_ENABLE MSR access in PMI
The perf PMI handler, intel_pmu_handle_irq(), currently does
unnecessary MSR accesses for PEBS_ENABLE MSR in
__intel_pmu_enable/disable_all() when PEBS is enabled.

When entering the handler, global ctrl is explicitly disabled. All
counters do not count anymore. It doesn't matter if PEBS is enabled
or not in a PMI handler.
Furthermore, for most cases, the cpuc->pebs_enabled is not changed in
PMI. The PEBS status doesn't change. The PEBS_ENABLE MSR doesn't need to
be changed either when exiting the handler.

PMI throttle may change the PEBS status during PMI handler. The
x86_pmu_stop() ends up in intel_pmu_pebs_disable() which can update
cpuc->pebs_enabled. But the MSR_IA32_PEBS_ENABLE is not updated
at the same time. Because the cpuc->enabled has been forced to 0.
The patch explicitly update the MSR_IA32_PEBS_ENABLE for this case.

Use ftrace to measure the duration of intel_pmu_handle_irq() on BDX.
   #perf record -e cycles:P -- ./tchain_edit

The average duration of intel_pmu_handle_irq():

  Without the patch       1.144 us
  With the patch          1.025 us

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Link: https://lkml.kernel.org/r/20200121181338.3234-1-kan.liang@linux.intel.com
2020-02-11 13:23:48 +01:00