Commit Graph

35 Commits

Author SHA1 Message Date
Rob Herring e8a709dc2a perf: arm_spe: Print the version of SPE detected
There's up to 4 versions of SPE now. Let's add the version that's been
detected to the driver's informational print out.

Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20230206204746.1452942-1-robh@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-02-07 11:52:21 +00:00
Rob Herring 8d9190f00a perf: arm_spe: Add support for SPEv1.2 inverted event filtering
Arm SPEv1.2 (Arm v8.7/v9.2) adds a new feature called Inverted Event
Filter which excludes samples matching the event filter. The feature
mirrors the existing event filter in PMSEVFR_EL1 adding a new register,
PMSNEVFR_EL1, which has the same event bit assignments.

Tested-by: James Clark <james.clark@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Link: https://lore.kernel.org/r/20220825-arm-spe-v8-7-v4-8-327f860daf28@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-02-07 11:52:00 +00:00
Rob Herring 4998897b1e perf: arm_spe: Support new SPEv1.2/v8.7 'not taken' event
Arm SPEv1.2 (Armv8.7/v9.2) adds a new event, 'not taken', in bit 6 of
the PMSEVFR_EL1 register. Update arm_spe_pmsevfr_res0() to support the
additional event.

Tested-by: James Clark <james.clark@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20220825-arm-spe-v8-7-v4-6-327f860daf28@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-01-19 18:30:23 +00:00
Rob Herring 05e4c88e2b perf: arm_spe: Use new PMSIDR_EL1 register enums
Now that the SPE register definitions include enums for some PMSIDR_EL1
fields, use them in the driver in place of magic values.

Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20220825-arm-spe-v8-7-v4-5-327f860daf28@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-01-19 18:30:23 +00:00
Rob Herring 2d347ac233 perf: arm_spe: Drop BIT() and use FIELD_GET/PREP accessors
Now that generated sysregs are in place, update the register field
accesses. The use of BIT() is no longer needed with the new defines. Use
FIELD_GET and FIELD_PREP instead of open coding masking and shifting.

No functional change.

Tested-by: James Clark <james.clark@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20220825-arm-spe-v8-7-v4-4-327f860daf28@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-01-19 18:30:22 +00:00
Rob Herring c759ec850d arm64: Drop SYS_ from SPE register defines
We currently have a non-standard SYS_ prefix in the constants generated
for the SPE register bitfields. Drop this in preparation for automatic
register definition generation.

The SPE mask defines were unshifted, and the SPE register field
enumerations were shifted. The autogenerated defines are the opposite,
so make the necessary adjustments.

No functional changes.

Tested-by: James Clark <james.clark@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20220825-arm-spe-v8-7-v4-2-327f860daf28@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-01-19 18:30:22 +00:00
Rob Herring e080477a05 perf: arm_spe: Use feature numbering for PMSEVFR_EL1 defines
Similar to commit 121a8fc088 ("arm64/sysreg: Use feature numbering for
PMU and SPE revisions") use feature numbering instead of architecture
versions for the PMSEVFR_EL1 Res0 defines.

Tested-by: James Clark <james.clark@arm.com>
Signed-off-by: Rob Herring <robh@kernel.org>
Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com>
Link: https://lore.kernel.org/r/20220825-arm-spe-v8-7-v4-1-327f860daf28@kernel.org
Signed-off-by: Will Deacon <will@kernel.org>
2023-01-19 18:30:22 +00:00
Linus Torvalds 3871d93b82 Perf events updates for v6.1:
- PMU driver updates:
 
      - Add AMD Last Branch Record Extension Version 2 (LbrExtV2)
        feature support for Zen 4 processors.
 
      - Extend the perf ABI to provide branch speculation information,
        if available, and use this on CPUs that have it (eg. LbrExtV2).
 
      - Improve Intel PEBS TSC timestamp handling & integration.
 
      - Add Intel Raptor Lake S CPU support.
 
      - Add 'perf mem' and 'perf c2c' memory profiling support on
        AMD CPUs by utilizing IBS tagged load/store samples.
 
      - Clean up & optimize various x86 PMU details.
 
  - HW breakpoints:
 
      - Big rework to optimize the code for systems with hundreds of CPUs and
        thousands of breakpoints:
 
         - Replace the nr_bp_mutex global mutex with the bp_cpuinfo_sem
 	  per-CPU rwsem that is read-locked during most of the key operations.
 
 	- Improve the O(#cpus * #tasks) logic in toggle_bp_slot()
 	  and fetch_bp_busy_slots().
 
 	- Apply micro-optimizations & cleanups.
 
   - Misc cleanups & enhancements.
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'perf-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf events updates from Ingo Molnar:
 "PMU driver updates:

   - Add AMD Last Branch Record Extension Version 2 (LbrExtV2) feature
     support for Zen 4 processors.

   - Extend the perf ABI to provide branch speculation information, if
     available, and use this on CPUs that have it (eg. LbrExtV2).

   - Improve Intel PEBS TSC timestamp handling & integration.

   - Add Intel Raptor Lake S CPU support.

   - Add 'perf mem' and 'perf c2c' memory profiling support on AMD CPUs
     by utilizing IBS tagged load/store samples.

   - Clean up & optimize various x86 PMU details.

  HW breakpoints:

   - Big rework to optimize the code for systems with hundreds of CPUs
     and thousands of breakpoints:

      - Replace the nr_bp_mutex global mutex with the bp_cpuinfo_sem
        per-CPU rwsem that is read-locked during most of the key
        operations.

      - Improve the O(#cpus * #tasks) logic in toggle_bp_slot() and
        fetch_bp_busy_slots().

      - Apply micro-optimizations & cleanups.

  - Misc cleanups & enhancements"

* tag 'perf-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (75 commits)
  perf/hw_breakpoint: Annotate tsk->perf_event_mutex vs ctx->mutex
  perf: Fix pmu_filter_match()
  perf: Fix lockdep_assert_event_ctx()
  perf/x86/amd/lbr: Adjust LBR regardless of filtering
  perf/x86/utils: Fix uninitialized var in get_branch_type()
  perf/uapi: Define PERF_MEM_SNOOPX_PEER in kernel header file
  perf/x86/amd: Support PERF_SAMPLE_PHY_ADDR
  perf/x86/amd: Support PERF_SAMPLE_ADDR
  perf/x86/amd: Support PERF_SAMPLE_{WEIGHT|WEIGHT_STRUCT}
  perf/x86/amd: Support PERF_SAMPLE_DATA_SRC
  perf/x86/amd: Add IBS OP_DATA2 DataSrc bit definitions
  perf/mem: Introduce PERF_MEM_LVLNUM_{EXTN_MEM|IO}
  perf/x86/uncore: Add new Raptor Lake S support
  perf/x86/cstate: Add new Raptor Lake S support
  perf/x86/msr: Add new Raptor Lake S support
  perf/x86: Add new Raptor Lake S support
  bpf: Check flags for branch stack in bpf_read_branch_records helper
  perf, hw_breakpoint: Fix use-after-free if perf_event_open() fails
  perf: Use sample_flags for raw_data
  perf: Use sample_flags for addr
  ...
2022-10-10 09:27:46 -07:00
Nathan Chancellor db74cd6337 arm64/sysreg: Fix a few missed conversions
After the conversion to automatically generating the ID_AA64DFR0_EL1
definition names, the build fails in a few different places because some
of the definitions were not changed to their new names along the way.
Update the names to resolve the build errors.

Fixes: c0357a73fa ("arm64/sysreg: Align field names in ID_AA64DFR0_EL1 with architecture")
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
Reviewed-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20220919160928.3905780-1-nathan@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2022-09-21 09:24:29 +01:00
Anshuman Khandual 91207f6261 arm64/perf: Assert all platform event flags are within PERF_EVENT_FLAG_ARCH
Ensure all platform specific event flags are within PERF_EVENT_FLAG_ARCH.

Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: James Clark <james.clark@arm.com>
Link: https://lkml.kernel.org/r/20220907091924.439193-4-anshuman.khandual@arm.com
2022-09-07 21:54:01 +02:00
Anshuman Khandual 92f2b8bafa drivers/perf: arm_spe: Fix consistency of SYS_PMSCR_EL1.CX
The arm_spe_pmu driver will enable SYS_PMSCR_EL1.CX in order to add CONTEXT
packets into the traces, if the owner of the perf event runs with required
capabilities i.e CAP_PERFMON or CAP_SYS_ADMIN via perfmon_capable() helper.

The value of this bit is computed in the arm_spe_event_to_pmscr() function
but the check for capabilities happens in the pmu event init callback i.e
arm_spe_pmu_event_init(). This suggests that the value of the CX bit should
remain consistent for the duration of the perf session.

However, the function arm_spe_event_to_pmscr() may be called later during
the event start callback i.e arm_spe_pmu_start() when the "current" process
is not the owner of the perf session, hence the CX bit setting is currently
not consistent.

One way to fix this, is by caching the required value of the CX bit during
the initialization of the PMU event, so that it remains consistent for the
duration of the session. It uses currently unused 'event->hw.flags' element
to cache perfmon_capable() value, which can be referred during event start
callback to compute SYS_PMSCR_EL1.CX. This ensures consistent availability
of context packets in the trace as per event owner capabilities.

Drop BIT(SYS_PMSCR_EL1_CX_SHIFT) check in arm_spe_pmu_event_init(), because
now CX bit cannot be set in arm_spe_event_to_pmscr() with perfmon_capable()
disabled.

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Alexey Budankov <alexey.budankov@linux.intel.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Fixes: d5d9696b03 ("drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension")
Reported-by: German Gomez <german.gomez@arm.com>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/20220714061302.2715102-1-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-07-19 18:50:09 +01:00
Shaokun Zhang 47a9ed88a4 drivers/perf: arm_spe: Expose saturating counter to 16-bit
In order to acquire more accurate latency, Armv8.8[1] has defined the
CountSize field to 16-bit saturating counters when it's 0b0011.

Let's support this new feature and expose its to user under sysfs.

[1] https://developer.arm.com/documentation/ddi0487/latest

Cc: Will Deacon <will@kernel.org>
Cc: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Shaokun Zhang <zhangshaokun@hisilicon.com>
Link: https://lore.kernel.org/r/20220429063307.63251-1-zhangshaokun@hisilicon.com
Signed-off-by: Will Deacon <will@kernel.org>
2022-05-06 15:10:00 +01:00
YueHaibing f9e36b388a perf: arm_spe: use DEVICE_ATTR_RO macro
Use DEVICE_ATTR_RO() helper instead of plain DEVICE_ATTR(),
which makes the code a bit shorter and easier to read.

Signed-off-by: YueHaibing <yuehaibing@huawei.com>
Link: https://lore.kernel.org/r/20210528061738.23392-1-yuehaibing@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-06-01 14:25:09 +01:00
Junhao He 27e4482075 drivers/perf: arm_spe_pmu: Fix some coding style issues
Fix some coding style issues reported by checkpatch.pl, including
following types:

WARNING: void function return statements are not generally useful
WARNING: Possible unnecessary 'out of memory' message

Signed-off-by: Junhao He <hejunhao2@hisilicon.com>
Signed-off-by: Jay Fang <f.fangjian@huawei.com>
Link: https://lore.kernel.org/r/1620736054-58412-2-git-send-email-f.fangjian@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-05-25 18:59:23 +01:00
Zihao Tang 700a9cf052 drivers/perf: convert sysfs snprintf family to sysfs_emit
Fix the following coccicheck warning:

./drivers/perf/hisilicon/hisi_uncore_pmu.c:128:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/fsl_imx8_ddr_perf.c:173:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm_spe_pmu.c:129:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm_smmu_pmu.c:563:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm_dsu_pmu.c:149:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm_dsu_pmu.c:139:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm-cmn.c:563:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm-cmn.c:351:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm-ccn.c:224:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm-cci.c:708:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm-cci.c:699:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm-cci.c:528:8-16: WARNING: use scnprintf or sprintf.
./drivers/perf/arm-cci.c:309:8-16: WARNING: use scnprintf or sprintf.

Signed-off-by: Zihao Tang <tangzihao1@hisilicon.com>
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Link: https://lore.kernel.org/r/1616148273-16374-2-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-03-25 12:55:44 +00:00
Rikard Falkeborn f0c140481d perf: Constify static struct attribute_group
The only usage is to put their addresses in an array of pointers to
const struct attribute group. Make them const to allow the compiler
to put them in read-only memory.

Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Link: https://lore.kernel.org/r/20210117212847.21319-5-rikard.falkeborn@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-20 17:51:23 +00:00
Wei Li 4a669e2432 drivers/perf: Add support for ARMv8.3-SPE
Armv8.3 extends the SPE by adding:
- Alignment field in the Events packet, and filtering on this event
  using PMSEVFR_EL1.
- Support for the Scalable Vector Extension (SVE).

The main additions for SVE are:
- Recording the vector length for SVE operations in the Operation Type
  packet. It is not possible to filter on vector length.
- Incomplete predicate and empty predicate fields in the Events packet,
  and filtering on these events using PMSEVFR_EL1.

Update the check of pmsevfr for empty/partial predicated SVE and
alignment event in SPE driver.

Signed-off-by: Wei Li <liwei391@huawei.com>
Link: https://lore.kernel.org/r/20201203141609.14148-1-liwei391@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2021-01-20 17:47:44 +00:00
Gustavo A. R. Silva df561f6688 treewide: Use fallthrough pseudo-keyword
Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
2020-08-23 17:36:59 -05:00
Qi Liu f32ed8eb0e drivers/perf: Prevent forced unbinding of PMU drivers
Forcefully unbinding PMU drivers during perf sampling will lead to
a kernel panic, because the perf upper-layer framework call a NULL
pointer in this situation.

To solve this issue, "suppress_bind_attrs" should be set to true, so
that bind/unbind can be disabled via sysfs and prevent unbinding PMU
drivers during perf sampling.

Signed-off-by: Qi Liu <liuqi115@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1594975763-32966-1-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-07-17 10:51:44 +01:00
Linus Torvalds 533b220f7b arm64 updates for 5.8
- Branch Target Identification (BTI)
 	* Support for ARMv8.5-BTI in both user- and kernel-space. This
 	  allows branch targets to limit the types of branch from which
 	  they can be called and additionally prevents branching to
 	  arbitrary code, although kernel support requires a very recent
 	  toolchain.
 
 	* Function annotation via SYM_FUNC_START() so that assembly
 	  functions are wrapped with the relevant "landing pad"
 	  instructions.
 
 	* BPF and vDSO updates to use the new instructions.
 
 	* Addition of a new HWCAP and exposure of BTI capability to
 	  userspace via ID register emulation, along with ELF loader
 	  support for the BTI feature in .note.gnu.property.
 
 	* Non-critical fixes to CFI unwind annotations in the sigreturn
 	  trampoline.
 
 - Shadow Call Stack (SCS)
 	* Support for Clang's Shadow Call Stack feature, which reserves
 	  platform register x18 to point at a separate stack for each
 	  task that holds only return addresses. This protects function
 	  return control flow from buffer overruns on the main stack.
 
 	* Save/restore of x18 across problematic boundaries (user-mode,
 	  hypervisor, EFI, suspend, etc).
 
 	* Core support for SCS, should other architectures want to use it
 	  too.
 
 	* SCS overflow checking on context-switch as part of the existing
 	  stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.
 
 - CPU feature detection
 	* Removed numerous "SANITY CHECK" errors when running on a system
 	  with mismatched AArch32 support at EL1. This is primarily a
 	  concern for KVM, which disabled support for 32-bit guests on
 	  such a system.
 
 	* Addition of new ID registers and fields as the architecture has
 	  been extended.
 
 - Perf and PMU drivers
 	* Minor fixes and cleanups to system PMU drivers.
 
 - Hardware errata
 	* Unify KVM workarounds for VHE and nVHE configurations.
 
 	* Sort vendor errata entries in Kconfig.
 
 - Secure Monitor Call Calling Convention (SMCCC)
 	* Update to the latest specification from Arm (v1.2).
 
 	* Allow PSCI code to query the SMCCC version.
 
 - Software Delegated Exception Interface (SDEI)
 	* Unexport a bunch of unused symbols.
 
 	* Minor fixes to handling of firmware data.
 
 - Pointer authentication
 	* Add support for dumping the kernel PAC mask in vmcoreinfo so
 	  that the stack can be unwound by tools such as kdump.
 
 	* Simplification of key initialisation during CPU bringup.
 
 - BPF backend
 	* Improve immediate generation for logical and add/sub
 	  instructions.
 
 - vDSO
 	- Minor fixes to the linker flags for consistency with other
 	  architectures and support for LLVM's unwinder.
 
 	- Clean up logic to initialise and map the vDSO into userspace.
 
 - ACPI
 	- Work around for an ambiguity in the IORT specification relating
 	  to the "num_ids" field.
 
 	- Support _DMA method for all named components rather than only
 	  PCIe root complexes.
 
 	- Minor other IORT-related fixes.
 
 - Miscellaneous
 	* Initialise debug traps early for KGDB and fix KDB cacheflushing
 	  deadlock.
 
 	* Minor tweaks to early boot state (documentation update, set
 	  TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).
 
 	* Refactoring and cleanup
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Will Deacon:
 "A sizeable pile of arm64 updates for 5.8.

  Summary below, but the big two features are support for Branch Target
  Identification and Clang's Shadow Call stack. The latter is currently
  arm64-only, but the high-level parts are all in core code so it could
  easily be adopted by other architectures pending toolchain support

  Branch Target Identification (BTI):

   - Support for ARMv8.5-BTI in both user- and kernel-space. This allows
     branch targets to limit the types of branch from which they can be
     called and additionally prevents branching to arbitrary code,
     although kernel support requires a very recent toolchain.

   - Function annotation via SYM_FUNC_START() so that assembly functions
     are wrapped with the relevant "landing pad" instructions.

   - BPF and vDSO updates to use the new instructions.

   - Addition of a new HWCAP and exposure of BTI capability to userspace
     via ID register emulation, along with ELF loader support for the
     BTI feature in .note.gnu.property.

   - Non-critical fixes to CFI unwind annotations in the sigreturn
     trampoline.

  Shadow Call Stack (SCS):

   - Support for Clang's Shadow Call Stack feature, which reserves
     platform register x18 to point at a separate stack for each task
     that holds only return addresses. This protects function return
     control flow from buffer overruns on the main stack.

   - Save/restore of x18 across problematic boundaries (user-mode,
     hypervisor, EFI, suspend, etc).

   - Core support for SCS, should other architectures want to use it
     too.

   - SCS overflow checking on context-switch as part of the existing
     stack limit check if CONFIG_SCHED_STACK_END_CHECK=y.

  CPU feature detection:

   - Removed numerous "SANITY CHECK" errors when running on a system
     with mismatched AArch32 support at EL1. This is primarily a concern
     for KVM, which disabled support for 32-bit guests on such a system.

   - Addition of new ID registers and fields as the architecture has
     been extended.

  Perf and PMU drivers:

   - Minor fixes and cleanups to system PMU drivers.

  Hardware errata:

   - Unify KVM workarounds for VHE and nVHE configurations.

   - Sort vendor errata entries in Kconfig.

  Secure Monitor Call Calling Convention (SMCCC):

   - Update to the latest specification from Arm (v1.2).

   - Allow PSCI code to query the SMCCC version.

  Software Delegated Exception Interface (SDEI):

   - Unexport a bunch of unused symbols.

   - Minor fixes to handling of firmware data.

  Pointer authentication:

   - Add support for dumping the kernel PAC mask in vmcoreinfo so that
     the stack can be unwound by tools such as kdump.

   - Simplification of key initialisation during CPU bringup.

  BPF backend:

   - Improve immediate generation for logical and add/sub instructions.

  vDSO:

   - Minor fixes to the linker flags for consistency with other
     architectures and support for LLVM's unwinder.

   - Clean up logic to initialise and map the vDSO into userspace.

  ACPI:

   - Work around for an ambiguity in the IORT specification relating to
     the "num_ids" field.

   - Support _DMA method for all named components rather than only PCIe
     root complexes.

   - Minor other IORT-related fixes.

  Miscellaneous:

   - Initialise debug traps early for KGDB and fix KDB cacheflushing
     deadlock.

   - Minor tweaks to early boot state (documentation update, set
     TEXT_OFFSET to 0x0, increase alignment of PE/COFF sections).

   - Refactoring and cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (148 commits)
  KVM: arm64: Move __load_guest_stage2 to kvm_mmu.h
  KVM: arm64: Check advertised Stage-2 page size capability
  arm64/cpufeature: Add get_arm64_ftr_reg_nowarn()
  ACPI/IORT: Remove the unused __get_pci_rid()
  arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR1 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64PFR0 register
  arm64/cpufeature: Add remaining feature bits in ID_AA64ISAR0 register
  arm64/cpufeature: Add remaining feature bits in ID_MMFR4 register
  arm64/cpufeature: Add remaining feature bits in ID_PFR0 register
  arm64/cpufeature: Introduce ID_MMFR5 CPU register
  arm64/cpufeature: Introduce ID_DFR1 CPU register
  arm64/cpufeature: Introduce ID_PFR2 CPU register
  arm64/cpufeature: Make doublelock a signed feature in ID_AA64DFR0
  arm64/cpufeature: Drop TraceFilt feature exposure from ID_DFR0 register
  arm64/cpufeature: Add explicit ftr_id_isar0[] for ID_ISAR0 register
  arm64: mm: Add asid_gen_match() helper
  firmware: smccc: Fix missing prototype warning for arm_smccc_version_init
  arm64: vdso: Fix CFI directives in sigreturn trampoline
  arm64: vdso: Don't prefix sigreturn trampoline with a BTI C instruction
  ...
2020-06-01 15:18:27 -07:00
Tang Bin 1f0d97bb70 drivers/perf: arm_spe_pmu: Avoid duplicate printouts
platform_get_irq() already screams on failure, so the redundant call to
dev_err() can be removed.

Signed-off-by: Tang Bin <tangbin@cmss.chinamobile.com>
Link: https://lore.kernel.org/r/20200402120330.19468-1-tangbin@cmss.chinamobile.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-04-30 21:49:32 +01:00
Alexey Budankov cea7d0d4a5 drivers/perf: Open access for CAP_PERFMON privileged process
Open access to monitoring for CAP_PERFMON privileged process.  Providing
the access under CAP_PERFMON capability singly, without the rest of
CAP_SYS_ADMIN credentials, excludes chances to misuse the credentials
and makes operation more secure.

CAP_PERFMON implements the principle of least privilege for performance
monitoring and observability operations (POSIX IEEE 1003.1e 2.2.2.39
principle of least privilege: A security design principle that states
that a process or program be granted only those privileges (e.g.,
capabilities) necessary to accomplish its legitimate function, and only
for the time that such privileges are actually required)

For backward compatibility reasons access to the monitoring remains open
for CAP_SYS_ADMIN privileged processes but CAP_SYS_ADMIN usage for
secure monitoring is discouraged with respect to CAP_PERFMON capability.

Signed-off-by: Alexey Budankov <alexey.budankov@linux.intel.com>
Reviewed-by: James Morris <jamorris@linux.microsoft.com>
Acked-by: Will Deacon <will@kernel.org>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Andi Kleen <ak@linux.intel.com>
Cc: Igor Lubashev <ilubashe@akamai.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Song Liu <songliubraving@fb.com>
Cc: Stephane Eranian <eranian@google.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: intel-gfx@lists.freedesktop.org
Cc: linux-doc@vger.kernel.org
Cc: linux-man@vger.kernel.org
Cc: linux-security-module@vger.kernel.org
Cc: selinux@vger.kernel.org
Link: http://lore.kernel.org/lkml/4ec1d6f7-548c-8d1c-f84a-cebeb9674e4e@linux.intel.com
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2020-04-16 12:19:09 -03:00
luanshi aaa1972715 perf: arm_spe: Remove unnecessary zero check on 'nr_pages'
We already check that the 'nr_pages' is > 2, so there's no need to check
that it's != 0 later on.

Signed-off-by: Liguang Zhang <zhangliguang@linux.alibaba.com>
Signed-off-by: Will Deacon <will@kernel.org>
2020-03-02 11:27:21 +00:00
Linus Torvalds dfd437a257 arm64 updates for 5.3:
- arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP}
 
 - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to
   manage the permissions of executable vmalloc regions more strictly
 
 - Slight performance improvement by keeping softirqs enabled while
   touching the FPSIMD/SVE state (kernel_neon_begin/end)
 
 - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new XAFLAG
   and AXFLAG instructions for floating point comparison flags
   manipulation) and FRINT (rounding floating point numbers to integers)
 
 - Re-instate ARM64_PSEUDO_NMI support which was previously marked as
   BROKEN due to some bugs (now fixed)
 
 - Improve parking of stopped CPUs and implement an arm64-specific
   panic_smp_self_stop() to avoid warning on not being able to stop
   secondary CPUs during panic
 
 - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI
   platforms
 
 - perf: DDR performance monitor support for iMX8QXP
 
 - cache_line_size() can now be set from DT or ACPI/PPTT if provided to
   cope with a system cache info not exposed via the CPUID registers
 
 - Avoid warning on hardware cache line size greater than
   ARCH_DMA_MINALIGN if the system is fully coherent
 
 - arm64 do_page_fault() and hugetlb cleanups
 
 - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep)
 
 - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the 'arm_boot_flags'
   introduced in 5.1)
 
 - CONFIG_RANDOMIZE_BASE now enabled in defconfig
 
 - Allow the selection of ARM64_MODULE_PLTS, currently only done via
   RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill
   over into the vmalloc area
 
 - Make ZONE_DMA32 configurable
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Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux

Pull arm64 updates from Catalin Marinas:

 - arm64 support for syscall emulation via PTRACE_SYSEMU{,_SINGLESTEP}

 - Wire up VM_FLUSH_RESET_PERMS for arm64, allowing the core code to
   manage the permissions of executable vmalloc regions more strictly

 - Slight performance improvement by keeping softirqs enabled while
   touching the FPSIMD/SVE state (kernel_neon_begin/end)

 - Expose a couple of ARMv8.5 features to user (HWCAP): CondM (new
   XAFLAG and AXFLAG instructions for floating point comparison flags
   manipulation) and FRINT (rounding floating point numbers to integers)

 - Re-instate ARM64_PSEUDO_NMI support which was previously marked as
   BROKEN due to some bugs (now fixed)

 - Improve parking of stopped CPUs and implement an arm64-specific
   panic_smp_self_stop() to avoid warning on not being able to stop
   secondary CPUs during panic

 - perf: enable the ARM Statistical Profiling Extensions (SPE) on ACPI
   platforms

 - perf: DDR performance monitor support for iMX8QXP

 - cache_line_size() can now be set from DT or ACPI/PPTT if provided to
   cope with a system cache info not exposed via the CPUID registers

 - Avoid warning on hardware cache line size greater than
   ARCH_DMA_MINALIGN if the system is fully coherent

 - arm64 do_page_fault() and hugetlb cleanups

 - Refactor set_pte_at() to avoid redundant READ_ONCE(*ptep)

 - Ignore ACPI 5.1 FADTs reported as 5.0 (infer from the
   'arm_boot_flags' introduced in 5.1)

 - CONFIG_RANDOMIZE_BASE now enabled in defconfig

 - Allow the selection of ARM64_MODULE_PLTS, currently only done via
   RANDOMIZE_BASE (and an erratum workaround), allowing modules to spill
   over into the vmalloc area

 - Make ZONE_DMA32 configurable

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (54 commits)
  perf: arm_spe: Enable ACPI/Platform automatic module loading
  arm_pmu: acpi: spe: Add initial MADT/SPE probing
  ACPI/PPTT: Add function to return ACPI 6.3 Identical tokens
  ACPI/PPTT: Modify node flag detection to find last IDENTICAL
  x86/entry: Simplify _TIF_SYSCALL_EMU handling
  arm64: rename dump_instr as dump_kernel_instr
  arm64/mm: Drop [PTE|PMD]_TYPE_FAULT
  arm64: Implement panic_smp_self_stop()
  arm64: Improve parking of stopped CPUs
  arm64: Expose FRINT capabilities to userspace
  arm64: Expose ARMv8.5 CondM capability to userspace
  arm64: defconfig: enable CONFIG_RANDOMIZE_BASE
  arm64: ARM64_MODULES_PLTS must depend on MODULES
  arm64: bpf: do not allocate executable memory
  arm64/kprobes: set VM_FLUSH_RESET_PERMS on kprobe instruction pages
  arm64/mm: wire up CONFIG_ARCH_HAS_SET_DIRECT_MAP
  arm64: module: create module allocations without exec permissions
  arm64: Allow user selection of ARM64_MODULE_PLTS
  acpi/arm64: ignore 5.1 FADTs that are reported as 5.0
  arm64: Allow selecting Pseudo-NMI again
  ...
2019-07-08 09:54:55 -07:00
Jeremy Linton d482e575fb perf: arm_spe: Enable ACPI/Platform automatic module loading
Lets add the MODULE_TABLE and platform id_table entries so that
the SPE driver can attach to the ACPI platform device created by
the core pmu code.

Tested-by: Hanjun Guo <hanjun.guo@linaro.org>
Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Will Deacon <will@kernel.org>
2019-06-27 16:53:53 +01:00
Thomas Gleixner caab277b1d treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 234
Based on 1 normalized pattern(s):

  this program is free software you can redistribute it and or modify
  it under the terms of the gnu general public license version 2 as
  published by the free software foundation this program is
  distributed in the hope that it will be useful but without any
  warranty without even the implied warranty of merchantability or
  fitness for a particular purpose see the gnu general public license
  for more details you should have received a copy of the gnu general
  public license along with this program if not see http www gnu org
  licenses

extracted by the scancode license scanner the SPDX license identifier

  GPL-2.0-only

has been chosen to replace the boilerplate/reference in 503 file(s).

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Reviewed-by: Alexios Zavras <alexios.zavras@intel.com>
Reviewed-by: Allison Randal <allison@lohutok.net>
Reviewed-by: Enrico Weigelt <info@metux.net>
Cc: linux-spdx@vger.kernel.org
Link: https://lkml.kernel.org/r/20190602204653.811534538@linutronix.de
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2019-06-19 17:09:07 +02:00
Will Deacon 14ae42a6f0 drivers/perf: arm_spe: Don't error on high-order pages for aux buf
Since commit 5768402fd9 ("perf/ring_buffer: Use high order allocations
for AUX buffers optimistically"), the perf core tends to back aux buffer
allocations with high-order pages with the order encoded in the
PagePrivate data. The Arm SPE driver explicitly rejects such pages,
causing the perf tool to fail with:

  | failed to mmap with 12 (Cannot allocate memory)

In actual fact, we can simply treat these pages just like any other
since the perf core takes care to populate the page array appropriately.
In theory we could try to map with PMDs where possible, but for now,
let's just get things working again.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Fixes: 5768402fd9 ("perf/ring_buffer: Use high order allocations for AUX buffers optimistically")
Reported-by: Hanjun Guo <guohanjun@huawei.com>
Tested-by: Hanjun Guo <guohanjun@huawei.com>
Tested-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2019-05-13 18:01:56 +01:00
Mathieu Poirier 840018668c perf/aux: Make perf_event accessible to setup_aux()
When pmu::setup_aux() is called the coresight PMU needs to know which
sink to use for the session by looking up the information in the
event's attr::config2 field.

As such simply replace the cpu information by the complete perf_event
structure and change all affected customers.

Signed-off-by: Mathieu Poirier <mathieu.poirier@linaro.org>
Reviewed-by: Suzuki Poulouse <suzuki.poulose@arm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Cc: Adrian Hunter <adrian.hunter@intel.com>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: H. Peter Anvin <hpa@zytor.com>
Cc: Heiko Carstens <heiko.carstens@de.ibm.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Will Deacon <will.deacon@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-s390@vger.kernel.org
Link: http://lkml.kernel.org/r/20190131184714.20388-2-mathieu.poirier@linaro.org
Signed-off-by: Arnaldo Carvalho de Melo <acme@redhat.com>
2019-02-06 10:00:39 -03:00
Nicholas Mc Guire 754a58db6a perf: arm_spe: handle devm_kasprintf() failure
devm_kasprintf() may return NULL on failure of internal allocation
thus the assignment to 'name' is not safe if unchecked. If NULL
is passed in for name then perf_pmu_register() would not fail
but rather silently jump to skip_type which is not the intent
here. As perf_pmu_register() may also return -ENOMEM returning
-ENOMEM in the (unlikely) failure case of devm_kasprintf() should
be fine here as well.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Fixes: d5d9696b03 ("drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension")
Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
[will: reworded error message]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-29 16:29:16 +00:00
Jeremy Linton 472dc9fa7c perf: arm_spe: Enable automatic DT loading
When built as a module, the spe driver isn't automatically
loaded on DT systems. Add the MODULE_DEVICE_TABLE entry.

Reviewed-by: Sudeep Holla <sudeep.holla@arm.com>
Signed-off-by: Jeremy Linton <jeremy.linton@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-11-21 13:16:34 +00:00
Wolfram Sang d0f2e42329 perf: simplify getting .drvdata
We should get drvdata from struct device directly. Going via
platform_device is an unneeded step back and forth.

Signed-off-by: Wolfram Sang <wsa+renesas@sang-engineering.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-05-21 18:02:35 +01:00
Arnd Bergmann fcd9f8315e perf: arm_spe: include linux/vmalloc.h for vmap()
On linux-next, I get a build failure in some configurations:

drivers/perf/arm_spe_pmu.c: In function 'arm_spe_pmu_setup_aux':
drivers/perf/arm_spe_pmu.c:857:14: error: implicit declaration of function 'vmap'; did you mean 'swap'? [-Werror=implicit-function-declaration]
  buf->base = vmap(pglist, nr_pages, VM_MAP, PAGE_KERNEL);
              ^~~~
              swap
drivers/perf/arm_spe_pmu.c:857:37: error: 'VM_MAP' undeclared (first use in this function); did you mean 'VM_MPX'?
  buf->base = vmap(pglist, nr_pages, VM_MAP, PAGE_KERNEL);
                                     ^~~~~~
                                     VM_MPX
drivers/perf/arm_spe_pmu.c:857:37: note: each undeclared identifier is reported only once for each function it appears in
drivers/perf/arm_spe_pmu.c: In function 'arm_spe_pmu_free_aux':
drivers/perf/arm_spe_pmu.c:878:2: error: implicit declaration of function 'vunmap'; did you mean 'iounmap'? [-Werror=implicit-function-declaration]

vmap() is declared in linux/vmalloc.h, so we should include that header file.

Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
[will: add additional missing #includes reported by Mark]
Signed-off-by: Will Deacon <will.deacon@arm.com>
2018-03-27 13:13:11 +01:00
Will Deacon 7a4a0c1555 perf: arm_spe: Fail device probe when arm64_kernel_unmapped_at_el0()
When running with the kernel unmapped whilst at EL0, the virtually-addressed
SPE buffer is also unmapped, which can lead to buffer faults if userspace
profiling is enabled and potentially also when writing back kernel samples
unless an expensive drain operation is performed on exception return.

For now, fail the SPE driver probe when arm64_kernel_unmapped_at_el0().

Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Tested-by: Laura Abbott <labbott@redhat.com>
Tested-by: Shanker Donthineni <shankerd@codeaurora.org>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-12-11 13:41:13 +00:00
Suzuki K Poulose 19b4aff202 perf: arm_spe: Prevent module unload while the PMU is in use
When the PMU driver is built as a module, the perf expects the
pmu->module to be valid, so that the driver is prevented from
being unloaded while it is in use. Fix the SPE pmu driver to
fill in this field.

Cc: Will Deacon <will.deacon@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-11-03 15:23:55 +00:00
Will Deacon d5d9696b03 drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension
The ARMv8.2 architecture introduces the optional Statistical Profiling
Extension (SPE).

SPE can be used to profile a population of operations in the CPU pipeline
after instruction decode. These are either architected instructions (i.e.
a dynamic instruction trace) or CPU-specific uops and the choice is fixed
statically in the hardware and advertised to userspace via caps/. Sampling
is controlled using a sampling interval, similar to a regular PMU counter,
but also with an optional random perturbation to avoid falling into patterns
where you continuously profile the same instruction in a hot loop.

After each operation is decoded, the interval counter is decremented. When
it hits zero, an operation is chosen for profiling and tracked within the
pipeline until it retires. Along the way, information such as TLB lookups,
cache misses, time spent to issue etc is captured in the form of a sample.
The sample is then filtered according to certain criteria (e.g. load
latency) that can be specified in the event config (described under
format/) and, if the sample satisfies the filter, it is written out to
memory as a record, otherwise it is discarded. Only one operation can
be sampled at a time.

The in-memory buffer is linear and virtually addressed, raising an
interrupt when it fills up. The PMU driver handles these interrupts to
give the appearance of a ring buffer, as expected by the AUX code.

The in-memory trace-like format is self-describing (though not parseable
in reverse) and written as a series of records, with each record
corresponding to a sample and consisting of a sequence of packets. These
packets are defined by the architecture, although some have CPU-specific
fields for recording information specific to the microarchitecture.

As a simple example, a record generated for a branch instruction may
consist of the following packets:

  0 (Address) : Virtual PC of the branch instruction
  1 (Type)    : Conditional direct branch
  2 (Counter) : Number of cycles taken from Dispatch to Issue
  3 (Address) : Virtual branch target + condition flags
  4 (Counter) : Number of cycles taken from Dispatch to Complete
  5 (Events)  : Mispredicted as not-taken
  6 (END)     : End of record

It is also possible to toggle properties such as timestamp packets in
each record.

This patch adds support for SPE in the form of a new perf driver.

Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Reviewed-by: Mark Rutland <mark.rutland@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
2017-10-18 12:53:34 +01:00