<feed xmlns='http://www.w3.org/2005/Atom'>
<title>kernel/linux.git/include/linux/perf_event.h, branch linux-6.9.y</title>
<subtitle>Linux kernel stable tree (mirror)</subtitle>
<id>https://git.radix-linux.su/kernel/linux.git/atom?h=linux-6.9.y</id>
<link rel='self' href='https://git.radix-linux.su/kernel/linux.git/atom?h=linux-6.9.y'/>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/'/>
<updated>2023-11-15T09:15:40+00:00</updated>
<entry>
<title>Merge branch 'tip/perf/urgent'</title>
<updated>2023-11-15T09:15:40+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2023-11-15T09:15:40+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=5d2d4a9f603a47403395408f64b1261ca61f6d50'/>
<id>urn:sha1:5d2d4a9f603a47403395408f64b1261ca61f6d50</id>
<content type='text'>
Avoid conflicts, base on fixes.

Signed-off-by: Peter Zijlstra &lt;peterz@infradead.org&gt;
</content>
</entry>
<entry>
<title>perf/core: Fix cpuctx refcounting</title>
<updated>2023-11-15T03:18:31+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2023-06-09T10:34:46+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=889c58b3155ff4c8e8671c95daef63d6fabbb6b1'/>
<id>urn:sha1:889c58b3155ff4c8e8671c95daef63d6fabbb6b1</id>
<content type='text'>
Audit of the refcounting turned up that perf_pmu_migrate_context()
fails to migrate the ctx refcount.

Fixes: bd2756811766 ("perf: Rewrite core context handling")
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lkml.kernel.org/r/20230612093539.085862001@infradead.org
Cc: &lt;stable@vger.kernel.org&gt;
</content>
</entry>
<entry>
<title>Merge tag 'perf-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip</title>
<updated>2023-10-30T23:44:35+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-10-30T23:44:35+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=bceb7accb7b60f9844807c7433af06493ed058b7'/>
<id>urn:sha1:bceb7accb7b60f9844807c7433af06493ed058b7</id>
<content type='text'>
Pull performance event updates from Ingo Molnar:
 - Add AMD Unified Memory Controller (UMC) events introduced with Zen 4
 - Simplify &amp; clean up the uncore management code
 - Fall back from RDPMC to RDMSR on certain uncore PMUs
 - Improve per-package and cstate event reading
 - Extend the Intel ref-cycles event to GP counters
 - Fix Intel MTL event constraints
 - Improve the Intel hybrid CPU handling code
 - Micro-optimize the RAPL code
 - Optimize perf_cgroup_switch()
 - Improve large AUX area error handling
 - Misc fixes and cleanups

* tag 'perf-core-2023-10-28' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (26 commits)
  perf/x86/amd/uncore: Pass through error code for initialization failures, instead of -ENODEV
  perf/x86/amd/uncore: Fix uninitialized return value in amd_uncore_init()
  x86/cpu: Fix the AMD Fam 17h, Fam 19h, Zen2 and Zen4 MSR enumerations
  perf: Optimize perf_cgroup_switch()
  perf/x86/amd/uncore: Add memory controller support
  perf/x86/amd/uncore: Add group exclusivity
  perf/x86/amd/uncore: Use rdmsr if rdpmc is unavailable
  perf/x86/amd/uncore: Move discovery and registration
  perf/x86/amd/uncore: Refactor uncore management
  perf/core: Allow reading package events from perf_event_read_local
  perf/x86/cstate: Allow reading the package statistics from local CPU
  perf/x86/intel/pt: Fix kernel-doc comments
  perf/x86/rapl: Annotate 'struct rapl_pmus' with __counted_by
  perf/core: Rename perf_proc_update_handler() -&gt; perf_event_max_sample_rate_handler(), for readability
  perf/x86/rapl: Fix "Using plain integer as NULL pointer" Sparse warning
  perf/x86/rapl: Use local64_try_cmpxchg in rapl_event_update()
  perf/x86/rapl: Stop doing cpu_relax() in the local64_cmpxchg() loop in rapl_event_update()
  perf/core: Bail out early if the request AUX area is out of bound
  perf/x86/intel: Extend the ref-cycles event to GP counters
  perf/x86/intel: Fix broken fixed event constraints extension
  ...
</content>
</entry>
<entry>
<title>perf: Add branch_sample_call_stack</title>
<updated>2023-10-27T13:05:09+00:00</updated>
<author>
<name>Kan Liang</name>
<email>kan.liang@linux.intel.com</email>
</author>
<published>2023-10-25T20:16:21+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=1f2376cd03dd3b965d130ed46a7c92769d614ba1'/>
<id>urn:sha1:1f2376cd03dd3b965d130ed46a7c92769d614ba1</id>
<content type='text'>
Add a helper function to check call stack sample type.

The later patch will invoke the function in several places.

Signed-off-by: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20231025201626.3000228-3-kan.liang@linux.intel.com
</content>
</entry>
<entry>
<title>perf: Add branch stack counters</title>
<updated>2023-10-27T13:05:08+00:00</updated>
<author>
<name>Kan Liang</name>
<email>kan.liang@linux.intel.com</email>
</author>
<published>2023-10-25T20:16:19+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=571d91dcadfa3cef499010b4eddb9b58b0da4d24'/>
<id>urn:sha1:571d91dcadfa3cef499010b4eddb9b58b0da4d24</id>
<content type='text'>
Currently, the additional information of a branch entry is stored in a
u64 space. With more and more information added, the space is running
out. For example, the information of occurrences of events will be added
for each branch.

Two places were suggested to append the counters.
https://lore.kernel.org/lkml/20230802215814.GH231007@hirez.programming.kicks-ass.net/
One place is right after the flags of each branch entry. It changes the
existing struct perf_branch_entry. The later ARCH specific
implementation has to be really careful to consistently pick
the right struct.
The other place is right after the entire struct perf_branch_stack.
The disadvantage is that the pointer of the extra space has to be
recorded. The common interface perf_sample_save_brstack() has to be
updated.

The latter is much straightforward, and should be easily understood and
maintained. It is implemented in the patch.

Add a new branch sample type, PERF_SAMPLE_BRANCH_COUNTERS, to indicate
the event which is recorded in the branch info.

The "u64 counters" may store the occurrences of several events. The
information regarding the number of events/counters and the width of
each counter should be exposed via sysfs as a reference for the perf
tool. Define the branch_counter_nr and branch_counter_width ABI here.
The support will be implemented later in the Intel-specific patch.

Suggested-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Signed-off-by: Kan Liang &lt;kan.liang@linux.intel.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20231025201626.3000228-1-kan.liang@linux.intel.com
</content>
</entry>
<entry>
<title>perf: Disallow mis-matched inherited group reads</title>
<updated>2023-10-19T08:09:42+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2023-10-18T11:56:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=32671e3799ca2e4590773fd0e63aaa4229e50c06'/>
<id>urn:sha1:32671e3799ca2e4590773fd0e63aaa4229e50c06</id>
<content type='text'>
Because group consistency is non-atomic between parent (filedesc) and children
(inherited) events, it is possible for PERF_FORMAT_GROUP read() to try and sum
non-matching counter groups -- with non-sensical results.

Add group_generation to distinguish the case where a parent group removes and
adds an event and thus has the same number, but a different configuration of
events as inherited groups.

This became a problem when commit fa8c269353d5 ("perf/core: Invert
perf_read_group() loops") flipped the order of child_list and sibling_list.
Previously it would iterate the group (sibling_list) first, and for each
sibling traverse the child_list. In this order, only the group composition of
the parent is relevant. By flipping the order the group composition of the
child (inherited) events becomes an issue and the mis-match in group
composition becomes evident.

That said; even prior to this commit, while reading of a group that is not
equally inherited was not broken, it still made no sense.

(Ab)use ECHILD as error return to indicate issues with child process group
composition.

Fixes: fa8c269353d5 ("perf/core: Invert perf_read_group() loops")
Reported-by: Budimir Markovic &lt;markovicbudimir@gmail.com&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20231018115654.GK33217@noisy.programming.kicks-ass.net
</content>
</entry>
<entry>
<title>perf: Optimize perf_cgroup_switch()</title>
<updated>2023-10-12T17:28:38+00:00</updated>
<author>
<name>Peter Zijlstra</name>
<email>peterz@infradead.org</email>
</author>
<published>2023-10-09T21:04:25+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=f06cc667f79909e9175460b167c277b7c64d3df0'/>
<id>urn:sha1:f06cc667f79909e9175460b167c277b7c64d3df0</id>
<content type='text'>
Namhyung reported that bd2756811766 ("perf: Rewrite core context handling")
regresses context switch overhead when perf-cgroup is in use together
with 'slow' PMUs like uncore.

Specifically, perf_cgroup_switch()'s perf_ctx_disable() /
ctx_sched_out() etc.. all iterate the full list of active PMUs for
that CPU, even if they don't have cgroup events.

Previously there was cgrp_cpuctx_list which linked the relevant PMUs
together, but that got lost in the rework. Instead of re-instruducing
a similar list, let the perf_event_pmu_context iteration skip those
that do not have cgroup events. This avoids growing multiple versions
of the perf_event_pmu_context iteration.

Measured performance (on a slightly different patch):

Before)

  $ taskset -c 0 ./perf bench sched pipe -l 10000 -G AAA,BBB
  # Running 'sched/pipe' benchmark:
  # Executed 10000 pipe operations between two processes

       Total time: 0.901 [sec]

        90.128700 usecs/op
            11095 ops/sec

After)

  $ taskset -c 0 ./perf bench sched pipe -l 10000 -G AAA,BBB
  # Running 'sched/pipe' benchmark:
  # Executed 10000 pipe operations between two processes

       Total time: 0.065 [sec]

         6.560100 usecs/op
           152436 ops/sec

Fixes: bd2756811766 ("perf: Rewrite core context handling")
Reported-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Debugged-by: Namhyung Kim &lt;namhyung@kernel.org&gt;
Signed-off-by: Peter Zijlstra (Intel) &lt;peterz@infradead.org&gt;
Link: https://lkml.kernel.org/r/20231009210425.GC6307@noisy.programming.kicks-ass.net
</content>
</entry>
<entry>
<title>perf/core: Rename perf_proc_update_handler() -&gt; perf_event_max_sample_rate_handler(), for readability</title>
<updated>2023-10-05T08:26:50+00:00</updated>
<author>
<name>Xiu Jianfeng</name>
<email>xiujianfeng@huawei.com</email>
</author>
<published>2023-07-21T09:06:07+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=e6814ec3ba1994561db9b1c05a80227d30cc18fa'/>
<id>urn:sha1:e6814ec3ba1994561db9b1c05a80227d30cc18fa</id>
<content type='text'>
Follow the naming pattern of the other sysctl handlers in perf.

Signed-off-by: Xiu Jianfeng &lt;xiujianfeng@huawei.com&gt;
Signed-off-by: Ingo Molnar &lt;mingo@kernel.org&gt;
Link: https://lore.kernel.org/r/20230721090607.172002-1-xiujianfeng@huawei.com
</content>
</entry>
<entry>
<title>Merge tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux</title>
<updated>2023-09-01T15:09:48+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-09-01T15:09:48+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=e0152e7481c6c63764d6ea8ee41af5cf9dfac5e9'/>
<id>urn:sha1:e0152e7481c6c63764d6ea8ee41af5cf9dfac5e9</id>
<content type='text'>
Pull RISC-V updates from Palmer Dabbelt:

 - Support for the new "riscv,isa-extensions" and "riscv,isa-base"
   device tree interfaces for probing extensions

 - Support for userspace access to the performance counters

 - Support for more instructions in kprobes

 - Crash kernels can be allocated above 4GiB

 - Support for KCFI

 - Support for ELFs in !MMU configurations

 - ARCH_KMALLOC_MINALIGN has been reduced to 8

 - mmap() defaults to sv48-sized addresses, with longer addresses hidden
   behind a hint (similar to Arm and Intel)

 - Also various fixes and cleanups

* tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits)
  lib/Kconfig.debug: Restrict DEBUG_INFO_SPLIT for RISC-V
  riscv: support PREEMPT_DYNAMIC with static keys
  riscv: Move create_tmp_mapping() to init sections
  riscv: Mark KASAN tmp* page tables variables as static
  riscv: mm: use bitmap_zero() API
  riscv: enable DEBUG_FORCE_FUNCTION_ALIGN_64B
  riscv: remove redundant mv instructions
  RISC-V: mm: Document mmap changes
  RISC-V: mm: Update pgtable comment documentation
  RISC-V: mm: Add tests for RISC-V mm
  RISC-V: mm: Restrict address space for sv39,sv48,sv57
  riscv: enable DMA_BOUNCE_UNALIGNED_KMALLOC for !dma_coherent
  riscv: allow kmalloc() caches aligned to the smallest value
  riscv: support the elf-fdpic binfmt loader
  binfmt_elf_fdpic: support 64-bit systems
  riscv: Allow CONFIG_CFI_CLANG to be selected
  riscv/purgatory: Disable CFI
  riscv: Add CFI error handling
  riscv: Add ftrace_stub_graph
  riscv: Add types to indirectly called assembly functions
  ...
</content>
</entry>
<entry>
<title>Merge tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux</title>
<updated>2023-08-29T00:34:54+00:00</updated>
<author>
<name>Linus Torvalds</name>
<email>torvalds@linux-foundation.org</email>
</author>
<published>2023-08-29T00:34:54+00:00</published>
<link rel='alternate' type='text/html' href='https://git.radix-linux.su/kernel/linux.git/commit/?id=542034175ca715d28522a59c1f88a58349f2765c'/>
<id>urn:sha1:542034175ca715d28522a59c1f88a58349f2765c</id>
<content type='text'>
Pull arm64 updates from Will Deacon:
 "I think we have a bit less than usual on the architecture side, but
  that's somewhat balanced out by a large crop of perf/PMU driver
  updates and extensions to our selftests.

  CPU features and system registers:

   - Advertise hinted conditional branch support (FEAT_HBC) to userspace

   - Avoid false positive "SANITY CHECK" warning when xCR registers
     differ outside of the length field

  Documentation:

   - Fix macro name typo in SME documentation

  Entry code:

   - Unmask exceptions earlier on the system call entry path

  Memory management:

   - Don't bother clearing PTE_RDONLY for dirty ptes in pte_wrprotect()
     and pte_modify()

  Perf and PMU drivers:

   - Initial support for Coresight TRBE devices on ACPI systems (the
     coresight driver changes will come later)

   - Fix hw_breakpoint single-stepping when called from bpf

   - Fixes for DDR PMU on i.MX8MP SoC

   - Add NUMA-awareness to Hisilicon PCIe PMU driver

   - Fix locking dependency issue in Arm DMC620 PMU driver

   - Workaround Hisilicon erratum 162001900 in the SMMUv3 PMU driver

   - Add support for Arm CMN-700 r3 parts to the CMN PMU driver

   - Add support for recent Arm Cortex CPU PMUs

   - Update Hisilicon PMU maintainers

  Selftests:

   - Add a bunch of new features to the hwcap test (JSCVT, PMULL, AES,
     SHA1, etc)

   - Fix SSVE test to leave streaming-mode after grabbing the signal
     context

   - Add new test for SVE vector-length changes with SME enabled

  Miscellaneous:

   - Allow compiler to warn on suspicious looking system register
     expressions

   - Work around SDEI firmware bug by aborting any running handlers on a
     kernel crash

   - Fix some harmless warnings when building with W=1

   - Remove some unused function declarations

   - Other minor fixes and cleanup"

* tag 'arm64-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/arm64/linux: (62 commits)
  drivers/perf: hisi: Update HiSilicon PMU maintainers
  arm_pmu: acpi: Add a representative platform device for TRBE
  arm_pmu: acpi: Refactor arm_spe_acpi_register_device()
  kselftest/arm64: Fix hwcaps selftest build
  hw_breakpoint: fix single-stepping when using bpf_overflow_handler
  arm64/sysreg: refactor deprecated strncpy
  kselftest/arm64: add jscvt feature to hwcap test
  kselftest/arm64: add pmull feature to hwcap test
  kselftest/arm64: add AES feature check to hwcap test
  kselftest/arm64: add SHA1 and related features to hwcap test
  arm64: sysreg: Generate C compiler warnings on {read,write}_sysreg_s arguments
  kselftest/arm64: build BTI tests in output directory
  perf/imx_ddr: don't enable counter0 if none of 4 counters are used
  perf/imx_ddr: speed up overflow frequency of cycle
  drivers/perf: hisi: Schedule perf session according to locality
  kselftest/arm64: fix a memleak in zt_regs_run()
  perf/arm-dmc620: Fix dmc620_pmu_irqs_lock/cpu_hotplug_lock circular lock dependency
  perf/smmuv3: Add MODULE_ALIAS for module auto loading
  perf/smmuv3: Enable HiSilicon Erratum 162001900 quirk for HIP08/09
  kselftest/arm64: Size sycall-abi buffers for the actual maximum VL
  ...
</content>
</entry>
</feed>
