178 Commits

Author SHA1 Message Date
Breno Leitao
263f5ecaf7 perf/x86/amd/core: Always clear status for idx
The variable 'status' (which contains the unhandled overflow bits) is
not being properly masked in some cases, displaying the following
warning:

  WARNING: CPU: 156 PID: 475601 at arch/x86/events/amd/core.c:972 amd_pmu_v2_handle_irq+0x216/0x270

This seems to be happening because the loop is being continued before
the status bit being unset, in case x86_perf_event_set_period()
returns 0. This is also causing an inconsistency because the "handled"
counter is incremented, but the status bit is not cleaned.

Move the bit cleaning together above, together when the "handled"
counter is incremented.

Fixes: 7685665c390d ("perf/x86/amd/core: Add PerfMonV2 overflow handling")
Signed-off-by: Breno Leitao <leitao@debian.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sandipan Das <sandipan.das@amd.com>
Link: https://lore.kernel.org/r/20230321113338.1669660-1-leitao@debian.org
2023-03-21 14:43:05 +01:00
Linus Torvalds
1f2d9ffc7a Scheduler updates in this cycle are:
- Improve the scalability of the CFS bandwidth unthrottling logic
    with large number of CPUs.
 
  - Fix & rework various cpuidle routines, simplify interaction with
    the generic scheduler code. Add __cpuidle methods as noinstr to
    objtool's noinstr detection and fix boatloads of cpuidle bugs & quirks.
 
  - Add new ABI: introduce MEMBARRIER_CMD_GET_REGISTRATIONS,
    to query previously issued registrations.
 
  - Limit scheduler slice duration to the sysctl_sched_latency period,
    to improve scheduling granularity with a large number of SCHED_IDLE
    tasks.
 
  - Debuggability enhancement on sys_exit(): warn about disabled IRQs,
    but also enable them to prevent a cascade of followup problems and
    repeat warnings.
 
  - Fix the rescheduling logic in prio_changed_dl().
 
  - Micro-optimize cpufreq and sched-util methods.
 
  - Micro-optimize ttwu_runnable()
 
  - Micro-optimize the idle-scanning in update_numa_stats(),
    select_idle_capacity() and steal_cookie_task().
 
  - Update the RSEQ code & self-tests
 
  - Constify various scheduler methods
 
  - Remove unused methods
 
  - Refine __init tags
 
  - Documentation updates
 
  - ... Misc other cleanups, fixes
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmPzbJwRHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1iIvA//ZcEaB8Z6ChLRQjM+bsaudKJu3pdLQbPK
 iYbP8Da+LsAfxbEfYuGV3m+jIp0LlBOtsI/EezxQrXV+V7FvNyAX9Y00eEu/zlj8
 7Jn3LMy/DBYTwH7LwVdcU0MyIVI8ZPc6WNnkx0LOtGZn8n+qfHPSDzcP3CW+a5AV
 UvllPYpYyEmsX0Eby7CF4Ue8mSmbViw/xR3rNr8ZSve0c25XzKabw8O9kE3jiHxP
 d/zERJoAYeDyYUEuZqhfn5dTlB4an4IjNEkAfRE5SQ09RA8Gkxsa5Ar8gob9e9M1
 eQsdd4/bdhnrkM8L5qDZczqmgCTZ2bukQrxkBXhRDhLgoFxwAn77b+2ZjmIW3Lae
 AyGqRcDSg1q2oxaYm5ZiuO/t26aDOZu9vPHyHRDGt95EGbZlrp+GgeePyfCigJYz
 UmPdZAAcHdSymnnnlcvdG37WVvaVkpgWZzd8LbtBi23QR+Zc4WQ2IlgnUS5WKNNf
 VOBcAcP6E1IslDotZDQCc2dPFFQoQQEssVooyUc5oMytm7BsvxXLOeHG+Ncu/8uc
 H+U8Qn8jnqTxJbC5hkWQIJlhVKCq2FJrHxxySYTKROfUNcDgCmxboFeAcXTCIU1K
 T0S+sdoTS/CvtLklRkG0j6B8N4N98mOd9cFwUV3tX+/gMLMep3hCQs5L76JagvC5
 skkQXoONNaM=
 =l1nN
 -----END PGP SIGNATURE-----

Merge tag 'sched-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:

 - Improve the scalability of the CFS bandwidth unthrottling logic with
   large number of CPUs.

 - Fix & rework various cpuidle routines, simplify interaction with the
   generic scheduler code. Add __cpuidle methods as noinstr to objtool's
   noinstr detection and fix boatloads of cpuidle bugs & quirks.

 - Add new ABI: introduce MEMBARRIER_CMD_GET_REGISTRATIONS, to query
   previously issued registrations.

 - Limit scheduler slice duration to the sysctl_sched_latency period, to
   improve scheduling granularity with a large number of SCHED_IDLE
   tasks.

 - Debuggability enhancement on sys_exit(): warn about disabled IRQs,
   but also enable them to prevent a cascade of followup problems and
   repeat warnings.

 - Fix the rescheduling logic in prio_changed_dl().

 - Micro-optimize cpufreq and sched-util methods.

 - Micro-optimize ttwu_runnable()

 - Micro-optimize the idle-scanning in update_numa_stats(),
   select_idle_capacity() and steal_cookie_task().

 - Update the RSEQ code & self-tests

 - Constify various scheduler methods

 - Remove unused methods

 - Refine __init tags

 - Documentation updates

 - Misc other cleanups, fixes

* tag 'sched-core-2023-02-20' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (110 commits)
  sched/rt: pick_next_rt_entity(): check list_entry
  sched/deadline: Add more reschedule cases to prio_changed_dl()
  sched/fair: sanitize vruntime of entity being placed
  sched/fair: Remove capacity inversion detection
  sched/fair: unlink misfit task from cpu overutilized
  objtool: mem*() are not uaccess safe
  cpuidle: Fix poll_idle() noinstr annotation
  sched/clock: Make local_clock() noinstr
  sched/clock/x86: Mark sched_clock() noinstr
  x86/pvclock: Improve atomic update of last_value in pvclock_clocksource_read()
  x86/atomics: Always inline arch_atomic64*()
  cpuidle: tracing, preempt: Squash _rcuidle tracing
  cpuidle: tracing: Warn about !rcu_is_watching()
  cpuidle: lib/bug: Disable rcu_is_watching() during WARN/BUG
  cpuidle: drivers: firmware: psci: Dont instrument suspend code
  KVM: selftests: Fix build of rseq test
  exit: Detect and fix irq disabled state in oops
  cpuidle, arm64: Fix the ARM64 cpuidle logic
  cpuidle: mvebu: Fix duplicate flags assignment
  sched/fair: Limit sched slice duration
  ...
2023-02-20 17:41:08 -08:00
Ingo Molnar
57a30218fa Linux 6.2-rc6
-----BEGIN PGP SIGNATURE-----
 
 iQFSBAABCAA8FiEEq68RxlopcLEwq+PEeb4+QwBBGIYFAmPW7E8eHHRvcnZhbGRz
 QGxpbnV4LWZvdW5kYXRpb24ub3JnAAoJEHm+PkMAQRiGf7MIAI0JnHN9WvtEukSZ
 E6j6+cEGWxsvD6q0g3GPolaKOCw7hlv0pWcFJFcUAt0jebspMdxV2oUGJ8RYW7Lg
 nCcHvEVswGKLAQtQSWw52qotW6fUfMPsNYYB5l31sm1sKH4Cgss0W7l2HxO/1LvG
 TSeNHX53vNAZ8pVnFYEWCSXC9bzrmU/VALF2EV00cdICmfvjlgkELGXoLKJJWzUp
 s63fBHYGGURSgwIWOKStoO6HNo0j/F/wcSMx8leY8qDUtVKHj4v24EvSgxUSDBER
 ch3LiSQ6qf4sw/z7pqruKFthKOrlNmcc0phjiES0xwwGiNhLv0z3rAhc4OM2cgYh
 SDc/Y/c=
 =zpaD
 -----END PGP SIGNATURE-----

Merge tag 'v6.2-rc6' into sched/core, to pick up fixes

Pick up fixes before merging another batch of cpuidle updates.

Signed-off-by: Ingo Molnar <mingo@kernel.org>
2023-01-31 15:01:20 +01:00
Namhyung Kim
eb55b455ef perf/core: Add perf_sample_save_brstack() helper
When we saves the branch stack to the perf sample data, we needs to
update the sample flags and the dynamic size.  To make sure this is
done consistently, add the perf_sample_save_brstack() helper and
convert all call sites.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230118060559.615653-5-namhyung@kernel.org
2023-01-18 11:57:20 +01:00
Namhyung Kim
0a9081cf0a perf/core: Add perf_sample_save_raw_data() helper
When we save the raw_data to the perf sample data, we need to update
the sample flags and the dynamic size.  To make sure this is done
consistently, add the perf_sample_save_raw_data() helper and convert
all call sites.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230118060559.615653-4-namhyung@kernel.org
2023-01-18 11:57:19 +01:00
Namhyung Kim
31046500c1 perf/core: Add perf_sample_save_callchain() helper
When we save the callchain to the perf sample data, we need to update
the sample flags and the dynamic size.  To ensure this is done consistently,
add the perf_sample_save_callchain() helper and convert all call sites.

Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Jiri Olsa <jolsa@kernel.org>
Acked-by: Song Liu <song@kernel.org>
Acked-by: Peter Zijlstra <peterz@infradead.org>
Link: https://lore.kernel.org/r/20230118060559.615653-3-namhyung@kernel.org
2023-01-18 11:57:19 +01:00
Peter Zijlstra
1f7c232ee0 x86/perf/amd: Remove tracing from perf_lopwr_cb()
The perf_lopwr_cb() function is called from the idle routines; there
is no RCU there, we must not enter tracing.

Use __always_inline, noidle annotations and existing no-trace methods.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Tested-by: Tony Lindgren <tony@atomide.com>
Tested-by: Ulf Hansson <ulf.hansson@linaro.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Acked-by: Frederic Weisbecker <frederic@kernel.org>
Link: https://lore.kernel.org/r/20230112195539.392862891@infradead.org
2023-01-13 11:03:21 +01:00
Colin Ian King
08245672cd perf/x86/amd: fix potential integer overflow on shift of a int
The left shift of int 32 bit integer constant 1 is evaluated using 32 bit
arithmetic and then passed as a 64 bit function argument. In the case where
i is 32 or more this can lead to an overflow.  Avoid this by shifting
using the BIT_ULL macro instead.

Fixes: 471af006a747 ("perf/x86/amd: Constrain Large Increment per Cycle events")
Signed-off-by: Colin Ian King <colin.i.king@gmail.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ian Rogers <irogers@google.com>
Acked-by: Kim Phillips <kim.phillips@amd.com>
Link: https://lore.kernel.org/r/20221202135149.1797974-1-colin.i.king@gmail.com
2022-12-27 12:44:00 +01:00
Linus Torvalds
add7695957 Perf events updates for v6.2:
- Thoroughly rewrite the data structures that implement perf task context handling,
    with the goal of fixing various quirks and unfeatures both in already merged,
    and in upcoming proposed code.
 
    The old data structure is the per task and per cpu perf_event_contexts:
 
          task_struct::perf_events_ctxp[] <-> perf_event_context <-> perf_cpu_context
               ^                                 |    ^     |           ^
               `---------------------------------'    |     `--> pmu ---'
                                                      v           ^
                                                 perf_event ------'
 
    In this new design this is replaced with a single task context and
    a single CPU context, plus intermediate data-structures:
 
          task_struct::perf_event_ctxp -> perf_event_context <- perf_cpu_context
               ^                           |   ^ ^
               `---------------------------'   | |
                                               | |    perf_cpu_pmu_context <--.
                                               | `----.    ^                  |
                                               |      |    |                  |
                                               |      v    v                  |
                                               | ,--> perf_event_pmu_context  |
                                               | |                            |
                                               | |                            |
                                               v v                            |
                                          perf_event ---> pmu ----------------'
 
    [ See commit bd2756811766 for more details. ]
 
    This rewrite was developed by Peter Zijlstra and Ravi Bangoria.
 
  - Optimize perf_tp_event()
 
  - Update the Intel uncore PMU driver, extending it with UPI topology discovery
    on various hardware models.
 
  - Misc fixes & cleanups
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
 -----BEGIN PGP SIGNATURE-----
 
 iQJFBAABCgAvFiEEBpT5eoXrXCwVQwEKEnMQ0APhK1gFAmOXjuURHG1pbmdvQGtl
 cm5lbC5vcmcACgkQEnMQ0APhK1j+VhAAknimsLwenTHCGQp7yqsWSKfBr9KI2UgD
 ZgtQuuwRwSzwqAEwC5Mt6zcIkxRNhU1ookFPqQbpY3XA0W4aNakUk8bDF8QIEKW0
 MFWxn7PtReWqKcUay2oEGGurqZ5OtfpljJGxigQh5oVeMGc+itIwHF2JefeyoRnu
 pq7R2qDgOBb7Np4lWTdqXGmKufzp04/nely2IZQBO8x80cGRZiKQIrGrch6vLUf7
 3iEz9rwmvPyz0aczYSpa/duEZDMLm4lWNK4oMUEXuUWC8gU7CUzBJsJ3AS5NgxAu
 yGBXe/s7GHqwtc/F30l5gK/J5WAyK83IF7sckxTj0dBUpyC6wQwwYPm8BaCAMoqN
 X6mU7Ve938Siih1TyOBZfZsrtDDILhV2N/nku2erb3iqes26u0RcT25rWtu9Yqvn
 hm4Gm6cmkHWq4EOHSBvAdC7l7lDZ3fyVI5+8nN9ly9Qv867HjG70dvIr9iEEolpX
 rhFAz8r/NwTXhDY0AmFZcOkrnNV3IuHtibJ/9wJlgJNqDPqN12Wxqdzy0Nj3HH6G
 EsukBO05cWaDS0gB8MpaO6Q6YtqAr87ZY+afHDBwcfkME50/CyBLr5rd47dTR+Ip
 B+zreYKcaNHdEMd1A9KULRTTDnEjlXYMwjVVJiPRV0jcmA3dHmM46HN5Ae9NdO6+
 R2BAWv9XR6M=
 =KNaI
 -----END PGP SIGNATURE-----

Merge tag 'perf-core-2022-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull perf events updates from Ingo Molnar:

 - Thoroughly rewrite the data structures that implement perf task
   context handling, with the goal of fixing various quirks and
   unfeatures both in already merged, and in upcoming proposed code.

   The old data structure is the per task and per cpu
   perf_event_contexts:

         task_struct::perf_events_ctxp[] <-> perf_event_context <-> perf_cpu_context
              ^                                 |    ^     |           ^
              `---------------------------------'    |     `--> pmu ---'
                                                     v           ^
                                                perf_event ------'

   In this new design this is replaced with a single task context and a
   single CPU context, plus intermediate data-structures:

         task_struct::perf_event_ctxp -> perf_event_context <- perf_cpu_context
              ^                           |   ^ ^
              `---------------------------'   | |
                                              | |    perf_cpu_pmu_context <--.
                                              | `----.    ^                  |
                                              |      |    |                  |
                                              |      v    v                  |
                                              | ,--> perf_event_pmu_context  |
                                              | |                            |
                                              | |                            |
                                              v v                            |
                                         perf_event ---> pmu ----------------'

   [ See commit bd2756811766 for more details. ]

   This rewrite was developed by Peter Zijlstra and Ravi Bangoria.

 - Optimize perf_tp_event()

 - Update the Intel uncore PMU driver, extending it with UPI topology
   discovery on various hardware models.

 - Misc fixes & cleanups

* tag 'perf-core-2022-12-12' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (25 commits)
  perf/x86/intel/uncore: Fix reference count leak in __uncore_imc_init_box()
  perf/x86/intel/uncore: Fix reference count leak in snr_uncore_mmio_map()
  perf/x86/intel/uncore: Fix reference count leak in hswep_has_limit_sbox()
  perf/x86/intel/uncore: Fix reference count leak in sad_cfg_iio_topology()
  perf/x86/intel/uncore: Make set_mapping() procedure void
  perf/x86/intel/uncore: Update sysfs-devices-mapping file
  perf/x86/intel/uncore: Enable UPI topology discovery for Sapphire Rapids
  perf/x86/intel/uncore: Enable UPI topology discovery for Icelake Server
  perf/x86/intel/uncore: Get UPI NodeID and GroupID
  perf/x86/intel/uncore: Enable UPI topology discovery for Skylake Server
  perf/x86/intel/uncore: Generalize get_topology() for SKX PMUs
  perf/x86/intel/uncore: Disable I/O stacks to PMU mapping on ICX-D
  perf/x86/intel/uncore: Clear attr_update properly
  perf/x86/intel/uncore: Introduce UPI topology type
  perf/x86/intel/uncore: Generalize IIO topology support
  perf/core: Don't allow grouping events from different hw pmus
  perf/amd/ibs: Make IBS a core pmu
  perf: Fix function pointer case
  perf/x86/amd: Remove the repeated declaration
  perf: Fix possible memleak in pmu_dev_alloc()
  ...
2022-12-12 15:19:38 -08:00
Ravi Bangoria
30093056f7 perf/amd/ibs: Make IBS a core pmu
So far, only one pmu was allowed to be registered as core pmu and thus
IBS pmus were being registered as uncore. However, with the event context
rewrite, that limitation no longer exists and thus IBS pmus can also be
registered as core pmu. This makes IBS much more usable, for ex, user
will be able to do per-process precise monitoring on AMD:

Before patch:
  $ sudo perf record -e cycles:pp ls
  Error:
  Invalid event (cycles:pp) in per-thread mode, enable system wide with '-a'

After patch:
  $ sudo perf record -e cycles:pp ls
  [ perf record: Woken up 1 times to write data ]
  [ perf record: Captured and wrote 0.017 MB perf.data (33 samples) ]

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-by: Ian Rogers <irogers@google.com>
Link: https://lkml.kernel.org/r/20221115093904.1799-1-ravi.bangoria@amd.com
2022-11-24 11:09:19 +01:00
Ravi Bangoria
baa014b954 perf/x86/amd: Fix crash due to race between amd_pmu_enable_all, perf NMI and throttling
amd_pmu_enable_all() does:

      if (!test_bit(idx, cpuc->active_mask))
              continue;

      amd_pmu_enable_event(cpuc->events[idx]);

A perf NMI of another event can come between these two steps. Perf NMI
handler internally disables and enables _all_ events, including the one
which nmi-intercepted amd_pmu_enable_all() was in process of enabling.
If that unintentionally enabled event has very low sampling period and
causes immediate successive NMI, causing the event to be throttled,
cpuc->events[idx] and cpuc->active_mask gets cleared by x86_pmu_stop().
This will result in amd_pmu_enable_event() getting called with event=NULL
when amd_pmu_enable_all() resumes after handling the NMIs. This causes a
kernel crash:

  BUG: kernel NULL pointer dereference, address: 0000000000000198
  #PF: supervisor read access in kernel mode
  #PF: error_code(0x0000) - not-present page
  [...]
  Call Trace:
   <TASK>
   amd_pmu_enable_all+0x68/0xb0
   ctx_resched+0xd9/0x150
   event_function+0xb8/0x130
   ? hrtimer_start_range_ns+0x141/0x4a0
   ? perf_duration_warn+0x30/0x30
   remote_function+0x4d/0x60
   __flush_smp_call_function_queue+0xc4/0x500
   flush_smp_call_function_queue+0x11d/0x1b0
   do_idle+0x18f/0x2d0
   cpu_startup_entry+0x19/0x20
   start_secondary+0x121/0x160
   secondary_startup_64_no_verify+0xe5/0xeb
   </TASK>

amd_pmu_disable_all()/amd_pmu_enable_all() calls inside perf NMI handler
were recently added as part of BRS enablement but I'm not sure whether
we really need them. We can just disable BRS in the beginning and enable
it back while returning from NMI. This will solve the issue by not
enabling those events whose active_masks are set but are not yet enabled
in hw pmu.

Fixes: ada543459cab ("perf/x86/amd: Add AMD Fam19h Branch Sampling support")
Reported-by: Linux Kernel Functional Testing <lkft@linaro.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221114044029.373-1-ravi.bangoria@amd.com
2022-11-16 10:12:58 +01:00
Sandipan Das
bdfe345971 perf/x86/amd/uncore: Fix memory leak for events array
When a CPU comes online, the per-CPU NB and LLC uncore contexts are
freed but not the events array within the context structure. This
causes a memory leak as identified by the kmemleak detector.

  [...]
  unreferenced object 0xffff8c5944b8e320 (size 32):
    comm "swapper/0", pid 1, jiffies 4294670387 (age 151.072s)
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [<000000000759fb79>] amd_uncore_cpu_up_prepare+0xaf/0x230
      [<00000000ddc9e126>] cpuhp_invoke_callback+0x2cf/0x470
      [<0000000093e727d4>] cpuhp_issue_call+0x14d/0x170
      [<0000000045464d54>] __cpuhp_setup_state_cpuslocked+0x11e/0x330
      [<0000000069f67cbd>] __cpuhp_setup_state+0x6b/0x110
      [<0000000015365e0f>] amd_uncore_init+0x260/0x321
      [<00000000089152d2>] do_one_initcall+0x3f/0x1f0
      [<000000002d0bd18d>] kernel_init_freeable+0x1ca/0x212
      [<0000000030be8dde>] kernel_init+0x11/0x120
      [<0000000059709e59>] ret_from_fork+0x22/0x30
  unreferenced object 0xffff8c5944b8dd40 (size 64):
    comm "swapper/0", pid 1, jiffies 4294670387 (age 151.072s)
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
      00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    backtrace:
      [<00000000306efe8b>] amd_uncore_cpu_up_prepare+0x183/0x230
      [<00000000ddc9e126>] cpuhp_invoke_callback+0x2cf/0x470
      [<0000000093e727d4>] cpuhp_issue_call+0x14d/0x170
      [<0000000045464d54>] __cpuhp_setup_state_cpuslocked+0x11e/0x330
      [<0000000069f67cbd>] __cpuhp_setup_state+0x6b/0x110
      [<0000000015365e0f>] amd_uncore_init+0x260/0x321
      [<00000000089152d2>] do_one_initcall+0x3f/0x1f0
      [<000000002d0bd18d>] kernel_init_freeable+0x1ca/0x212
      [<0000000030be8dde>] kernel_init+0x11/0x120
      [<0000000059709e59>] ret_from_fork+0x22/0x30
  [...]

Fix the problem by freeing the events array before freeing the uncore
context.

Fixes: 39621c5808f5 ("perf/x86/amd/uncore: Use dynamic events array")
Reported-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Tested-by: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: <stable@vger.kernel.org>
Link: https://lore.kernel.org/r/4fa9e5ac6d6e41fa889101e7af7e6ba372cfea52.1662613255.git.sandipan.das@amd.com
2022-11-09 12:38:01 +01:00
Peter Zijlstra
bd27568117 perf: Rewrite core context handling
There have been various issues and limitations with the way perf uses
(task) contexts to track events. Most notable is the single hardware
PMU task context, which has resulted in a number of yucky things (both
proposed and merged).

Notably:
 - HW breakpoint PMU
 - ARM big.little PMU / Intel ADL PMU
 - Intel Branch Monitoring PMU
 - AMD IBS PMU
 - S390 cpum_cf PMU
 - PowerPC trace_imc PMU

*Current design:*

Currently we have a per task and per cpu perf_event_contexts:

  task_struct::perf_events_ctxp[] <-> perf_event_context <-> perf_cpu_context
       ^                                 |    ^     |           ^
       `---------------------------------'    |     `--> pmu ---'
                                              v           ^
                                         perf_event ------'

Each task has an array of pointers to a perf_event_context. Each
perf_event_context has a direct relation to a PMU and a group of
events for that PMU. The task related perf_event_context's have a
pointer back to that task.

Each PMU has a per-cpu pointer to a per-cpu perf_cpu_context, which
includes a perf_event_context, which again has a direct relation to
that PMU, and a group of events for that PMU.

The perf_cpu_context also tracks which task context is currently
associated with that CPU and includes a few other things like the
hrtimer for rotation etc.

Each perf_event is then associated with its PMU and one
perf_event_context.

*Proposed design:*

New design proposed by this patch reduce to a single task context and
a single CPU context but adds some intermediate data-structures:

  task_struct::perf_event_ctxp -> perf_event_context <- perf_cpu_context
       ^                           |   ^ ^
       `---------------------------'   | |
                                       | |    perf_cpu_pmu_context <--.
                                       | `----.    ^                  |
                                       |      |    |                  |
                                       |      v    v                  |
                                       | ,--> perf_event_pmu_context  |
                                       | |                            |
                                       | |                            |
                                       v v                            |
                                  perf_event ---> pmu ----------------'

With the new design, perf_event_context will hold all events for all
pmus in the (respective pinned/flexible) rbtrees. This can be achieved
by adding pmu to rbtree key:

  {cpu, pmu, cgroup, group_index}

Each perf_event_context carries a list of perf_event_pmu_context which
is used to hold per-pmu-per-context state. For example, it keeps track
of currently active events for that pmu, a pmu specific task_ctx_data,
a flag to tell whether rotation is required or not etc.

Additionally, perf_cpu_pmu_context is used to hold per-pmu-per-cpu
state like hrtimer details to drive the event rotation, a pointer to
perf_event_pmu_context of currently running task and some other
ancillary information.

Each perf_event is associated to it's pmu, perf_event_context and
perf_event_pmu_context.

Further optimizations to current implementation are possible. For
example, ctx_resched() can be optimized to reschedule only single pmu
events.

Much thanks to Ravi for picking this up and pushing it towards
completion.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Co-developed-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20221008062424.313-1-ravi.bangoria@amd.com
2022-10-27 20:12:16 +02:00
Ravi Bangoria
cb6c18b5a4 perf/mem: Rename PERF_MEM_LVLNUM_EXTN_MEM to PERF_MEM_LVLNUM_CXL
PERF_MEM_LVLNUM_EXTN_MEM was introduced to cover CXL devices but it's
bit ambiguous name and also not generic enough to cover cxl.cache and
cxl.io devices. Rename it to PERF_MEM_LVLNUM_CXL to be more specific.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/f6268268-b4e9-9ed6-0453-65792644d953@amd.com
2022-10-27 10:27:32 +02:00
Stephane Eranian
3f9a1b3591 perf/x86/amd/lbr: Adjust LBR regardless of filtering
In case of fused compare and taken branch instructions, the AMD LBR points to
the compare instruction instead of the branch. Users of LBR usually expects
the from address to point to a branch instruction. The kernel has code to
adjust the from address via get_branch_type_fused(). However this correction
is only applied when a branch filter is applied. That means that if no
filter is present, the quality of the data is lower.

Fix the problem by applying the adjustment regardless of the filter setting,
bringing the AMD LBR to the same level as other LBR implementations.

Fixes: 245268c19f70 ("perf/x86/amd/lbr: Use fusion-aware branch classifier")
Signed-off-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Sandipan Das <sandipan.das@amd.com>
Link: https://lore.kernel.org/r/20220928184043.408364-3-eranian@google.com
2022-09-29 12:20:57 +02:00
Ravi Bangoria
5b26af6d2b perf/x86/amd: Support PERF_SAMPLE_PHY_ADDR
IBS_DC_PHYSADDR provides the physical data address for the tagged load/
store operation. Populate perf sample physical address using it.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220928095805.596-7-ravi.bangoria@amd.com
2022-09-29 12:20:56 +02:00
Ravi Bangoria
cb2bb85f7e perf/x86/amd: Support PERF_SAMPLE_ADDR
IBS_DC_LINADDR provides the linear data address for the tagged load/
store operation. Populate perf sample address using it.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220928095805.596-6-ravi.bangoria@amd.com
2022-09-29 12:20:55 +02:00
Ravi Bangoria
6b2ae4952e perf/x86/amd: Support PERF_SAMPLE_{WEIGHT|WEIGHT_STRUCT}
IbsDcMissLat indicates the number of clock cycles from when a miss is
detected in the data cache to when the data was delivered to the core.
Similarly, IbsTagToRetCtr provides number of cycles from when the op
was tagged to when the op was retired. Consider these fields for
sample->weight.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220928095805.596-5-ravi.bangoria@amd.com
2022-09-29 12:20:55 +02:00
Ravi Bangoria
7c10dd0a88 perf/x86/amd: Support PERF_SAMPLE_DATA_SRC
struct perf_mem_data_src is used to pass arch specific memory access
details into generic form. These details gets consumed by tools like
perf mem and c2c. IBS tagged load/store sample provides most of the
information needed for these tools. Add a logic to convert IBS
specific raw data into perf_mem_data_src.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220928095805.596-4-ravi.bangoria@amd.com
2022-09-29 12:20:55 +02:00
Namhyung Kim
838d9bb62d perf: Use sample_flags for raw_data
Use the new sample_flags to indicate whether the raw data field is
filled by the PMU driver.  Although it could check with the NULL,
follow the same rule with other fields.

Remove the raw field from the perf_sample_data_init() to minimize
the number of cache lines touched.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220921220032.2858517-2-namhyung@kernel.org
2022-09-27 22:50:24 +02:00
Namhyung Kim
b4e12b2d70 perf: Kill __PERF_SAMPLE_CALLCHAIN_EARLY
There's no in-tree user anymore.  Let's get rid of it.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220908214104.3851807-3-namhyung@kernel.org
2022-09-13 15:03:23 +02:00
Namhyung Kim
3749d33e51 perf: Use sample_flags for callchain
So that it can call perf_callchain() only if needed.  Historically it used
__PERF_SAMPLE_CALLCHAIN_EARLY but we can do that with sample_flags in the
struct perf_sample_data.

Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220908214104.3851807-1-namhyung@kernel.org
2022-09-13 15:03:22 +02:00
Peter Zijlstra
28f0f3c44b perf/x86: Change x86_pmu::limit_period signature
In preparation for making it a static_call, change the signature.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220829101321.573713839@infradead.org
2022-09-07 21:54:02 +02:00
Kan Liang
a9a931e266 perf: Use sample_flags for branch stack
Use the new sample_flags to indicate whether the branch stack is filled
by the PMU driver.

Remove the br_stack from the perf_sample_data_init() to minimize the number
of cache lines touched.

Signed-off-by: Kan Liang <kan.liang@linux.intel.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220901130959.1285717-4-kan.liang@linux.intel.com
2022-09-06 11:33:02 +02:00
Sandipan Das
0bc3be5b4b perf/x86/amd/lbr: Add LbrExtV2 branch speculation info support
Provide branch speculation information captured via AMD Last Branch Record
Extension Version 2 (LbrExtV2) by setting the speculation info in branch
records. The info is based on the "valid" and "spec" bits in the Branch To
registers.

Suggested-by: Stephane Eranian <eranian@google.com>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/ddc02f6320464cad0e3ff5bdb2314531568a91bc.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:45 +02:00
Sandipan Das
245268c19f perf/x86/amd/lbr: Use fusion-aware branch classifier
AMD Last Branch Record Extension Version 2 (LbrExtV2) can report a branch
from address that points to an instruction preceding the actual branch by
several bytes due to branch fusion and further optimizations in Zen4
processors.

In such cases, software should move forward sequentially in the instruction
stream from the reported address and the address of the first branch
encountered should be used instead. Hence, use the fusion-aware branch
classifier to determine the correct branch type and get the offset for
adjusting the branch from address.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/c324d2d0a9c3976da30b9563d09e50bfee0f264d.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:45 +02:00
Sandipan Das
f9c732249b perf/x86/amd/lbr: Add LbrExtV2 software branch filter support
With AMD Last Branch Record Extension Version 2 (LbrExtV2), it is necessary
to process the branch records further as hardware filtering is not granular
enough for identifying certain types of branches. E.g. to record system
calls, one should record far branches. The filter captures both far calls
and far returns but the irrelevant records are filtered out based on the
branch type as seen by the branch classifier.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/e51de057517f77788abd393c832e8dea616d489c.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:44 +02:00
Sandipan Das
f4f925dae7 perf/x86/amd/lbr: Add LbrExtV2 hardware branch filter support
If AMD Last Branch Record Extension Version 2 (LbrExtV2) is detected,
convert the requested branch filter (PERF_SAMPLE_BRANCH_* flags) to the
corresponding hardware filter value and stash it in the event data when
a branch stack is requested. The hardware filter value is also saved in
per-CPU areas for use during event scheduling.

Hardware filtering is provided by the LBR Branch Select register. It has
bits which when set, suppress recording of the following types of branches:

  * CPL = 0 (Kernel only)
  * CPL > 0 (Userspace only)
  * Conditional Branches
  * Near Relative Calls
  * Near Indirect Calls
  * Near Returns
  * Near Indirect Jumps (excluding Near Indirect Calls and Near Returns)
  * Near Relative Jumps (excluding Near Relative Calls)
  * Far Branches

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/9336af5c9785b8e14c62220fc0e6cfb10ab97de3.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:43 +02:00
Sandipan Das
ca5b7c0d96 perf/x86/amd/lbr: Add LbrExtV2 branch record support
If AMD Last Branch Record Extension Version 2 (LbrExtV2) is detected,
enable it alongside LBR Freeze on PMI when an event requests branch stack
i.e. PERF_SAMPLE_BRANCH_STACK.

Each branch record is represented by a pair of registers, LBR From and LBR
To. The freeze feature prevents any updates to these registers once a PMC
overflows. The contents remain unchanged until the freeze bit is cleared by
the PMI handler.

The branch records are read and copied to sample data before unfreezing.
However, only valid entries are copied. There is no additional register to
denote which of the register pairs represent the top of the stack (TOS)
since internal register renaming always ensures that the first pair (i.e.
index 0) is the one representing the most recent branch and so on.

The LBR registers are per-thread resources and are cleared explicitly
whenever a new task is scheduled in. There are no special implications on
the contents of these registers when transitioning to deep C-states.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/d3b8500a3627a0d4d0259b005891ee248f248d91.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:43 +02:00
Sandipan Das
703fb765f4 perf/x86/amd/lbr: Detect LbrExtV2 support
AMD Last Branch Record Extension Version 2 (LbrExtV2) is driven by Core PMC
overflows. It records recently taken branches up to the moment when the PMC
overflow occurs.

Detect the feature during PMU initialization and set the branch stack depth
using CPUID leaf 0x80000022 EBX.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/fc6e45378ada258f1bab79b0de6e05c393a8f1dd.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:43 +02:00
Sandipan Das
706460a96f perf/x86/amd/core: Add generic branch record interfaces
AMD processors that are capable of recording branches support either Branch
Sampling (BRS) or Last Branch Record (LBR). In preparation for adding Last
Branch Record Extension Version 2 (LbrExtV2) support, introduce new static
calls which act as gateways to call into the feature-dependent functions
based on what is available on the processor.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/b75dbc32663cb395f0d701167e952c6a6b0445a3.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:42 +02:00
Sandipan Das
9603aa79e8 perf/x86/amd/core: Refactor branch attributes
AMD processors that are capable of recording branches support either Branch
Sampling (BRS) or Last Branch Record (LBR). In preparation for adding Last
Branch Record Extension Version 2 (LbrExtV2) support, reuse the "branches"
capability to advertise information about both BRS and LBR but make the
"branch-brs" event exclusive to Family 19h processors that support BRS.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/ba4a4cde6db79b1c65c49834027bbdb8a915546b.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:42 +02:00
Sandipan Das
b40d0156f5 perf/x86/amd/brs: Move feature-specific functions
Move some of the Branch Sampling (BRS) specific functions out of the Core
events sources and into the BRS sources in preparation for adding other
mechanisms to record branches.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/b60283b57179475d18ee242d117c335c16733693.1660211399.git.sandipan.das@amd.com
2022-08-27 00:05:41 +02:00
Sandipan Das
f0fe9f3c7a perf/x86/amd/uncore: Add PerfMonV2 RDPMC assignments
The current RDPMC assignment scheme maps four DF PMCs and
six L3 PMCs from index 6 to 15.

If AMD Performance Monitoring Version 2 (PerfMonV2) is
supported, there may be additional DF counters available
which are mapped starting from index 16 i.e. just after
the L3 counters. Update the RDPMC assignments accordingly.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/1359379ef34da760f108b075ac138ab082caa3ba.1652954372.git.sandipan.das@amd.com
2022-06-13 10:15:14 +02:00
Sandipan Das
c390241a93 perf/x86/amd/uncore: Add PerfMonV2 DF event format
If AMD Performance Monitoring Version 2 (PerfMonV2) is
supported, use bits 0-7, 32-37 as EventSelect and bits
8-15, 24-27 as UnitMask for Data Fabric (DF) events.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/ffc24d5a3375b1d6e457d88e83241114de5c1942.1652954372.git.sandipan.das@amd.com
2022-06-13 10:15:14 +02:00
Sandipan Das
16b48c3f5e perf/x86/amd/uncore: Detect available DF counters
If AMD Performance Monitoring Version 2 (PerfMonV2) is
supported, use CPUID leaf 0x80000022 EBX to detect the
number of Data Fabric (DF) PMCs. This offers more
flexibility if the counts change in later processor
families.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/bac7b2806561e03f2acc7fdc9db94f102df80e1d.1652954372.git.sandipan.das@amd.com
2022-06-13 10:15:13 +02:00
Sandipan Das
847f3268bb perf/x86/amd/uncore: Use attr_update for format attributes
Use the update_attrs attribute group introduced by commit
f3a3a8257e5a ("perf/core: Add attr_groups_update into struct
pmu") and the is_visible() callback to populate the family
specifc attributes for uncore events.

The changes apply to attributes that are unique to families
such as slicemask for Family 17h and coreid for Family 19h.
The addition of common attributes such as event and umask,
whose formats change across families, remain unchanged.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/a5e4f4dd5c459199fc497e82b858ba09dc91c064.1652954372.git.sandipan.das@amd.com
2022-06-13 10:15:13 +02:00
Sandipan Das
39621c5808 perf/x86/amd/uncore: Use dynamic events array
If AMD Performance Monitoring Version 2 (PerfMonV2) is
supported, the number of available counters for a given
uncore PMU may not be fixed across families and models
and has to be determined at runtime.

The per-cpu uncore PMU data currently uses a fixed-sized
array for event information. Make it dynamic based on the
number of available counters.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/21eea0cb6de9d14f78d52d1d62637ae02bc900f5.1652954372.git.sandipan.das@amd.com
2022-06-13 10:15:13 +02:00
Sandipan Das
bae19fdd7e perf/x86/amd/core: Fix reloading events for SVM
Commit 1018faa6cf23 ("perf/x86/kvm: Fix Host-Only/Guest-Only
counting with SVM disabled") addresses an issue in which the
Host-Only bit in the counter control registers needs to be
masked off when SVM is not enabled.

The events need to be reloaded whenever SVM is enabled or
disabled for a CPU and this requires the PERF_CTL registers
to be reprogrammed using {enable,disable}_all(). However,
PerfMonV2 variants of these functions do not reprogram the
PERF_CTL registers. Hence, the legacy enable_all() function
should also be called.

Fixes: 9622e67e3980 ("perf/x86/amd/core: Add PerfMonV2 counter control")
Reported-by: Like Xu <likexu@tencent.com>
Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220518084327.464005-1-sandipan.das@amd.com
2022-05-19 23:46:14 +02:00
Borislav Petkov
841b51e4a3 perf/x86/amd: Run AMD BRS code only on supported hw
This fires on a Fam16h machine here:

 unchecked MSR access error: WRMSR to 0xc000010f (tried to write 0x0000000000000018) \
    at rIP: 0xffffffff81007db1 (amd_brs_reset+0x11/0x50)
 Call Trace:
  <TASK>
  amd_pmu_cpu_starting
  ? x86_pmu_dead_cpu
  x86_pmu_starting_cpu
  cpuhp_invoke_callback
  ? x86_pmu_starting_cpu
  ? x86_pmu_dead_cpu
  cpuhp_issue_call
  ? x86_pmu_starting_cpu
  __cpuhp_setup_state_cpuslocked
  ? x86_pmu_dead_cpu
  ? x86_pmu_starting_cpu
  __cpuhp_setup_state
  ? map_vsyscall
  init_hw_perf_events
  ? map_vsyscall
  do_one_initcall
  ? _raw_spin_unlock_irqrestore
  ? try_to_wake_up
  kernel_init_freeable
  ? rest_init
  kernel_init
  ret_from_fork

because that CPU hotplug callback gets executed on any AMD CPU - not
only on the BRS-enabled ones. Check the BRS feature bit properly.

Signed-off-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Acked-By: Stephane Eranian <eranian@google.com>
Link: https://lkml.kernel.org/r/20220516154838.7044-1-bp@alien8.de
2022-05-18 00:08:26 +02:00
Peter Zijlstra
3c27b0c6ea perf/x86/amd: Fix AMD BRS period adjustment
There's two problems with the current amd_brs_adjust_period() code:

 - it isn't in fact AMD specific and wil always adjust the period;

 - it adjusts the period, while it should only adjust the event count,
   resulting in repoting a short period.

Fix this by using x86_pmu.limit_period, this makes it specific to the
AMD BRS case and ensures only the event count is adjusted while the
reported period is unmodified.

Fixes: ba2fe7500845 ("perf/x86/amd: Add AMD branch sampling period adjustment")
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
2022-05-18 00:08:25 +02:00
Zucheng Zheng
bc469ddf67 perf/x86/amd: Remove unused variable 'hwc'
'hwc' is never used in amd_pmu_enable_all(), so remove it.

Signed-off-by: Zucheng Zheng <zhengzucheng@huawei.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220421111031.174698-1-zhengzucheng@huawei.com
2022-05-12 16:28:46 +02:00
Ravi Bangoria
838de1d843 perf/amd/ibs: Advertise zen4_ibs_extensions as pmu capability attribute
PMU driver can advertise certain feature via capability attribute('caps'
sysfs directory) which can be consumed by userspace tools like perf. Add
zen4_ibs_extensions capability attribute for IBS pmus. This attribute
will be enabled when CPUID_Fn8000001B_EAX[11] is set.

With patch on Zen4:

  $ ls /sys/bus/event_source/devices/ibs_op/caps
  zen4_ibs_extensions

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220509044914.1473-5-ravi.bangoria@amd.com
2022-05-11 16:27:10 +02:00
Ravi Bangoria
ba5d35b442 perf/amd/ibs: Add support for L3 miss filtering
IBS L3 miss filtering works by tagging an instruction on IBS counter
overflow and generating an NMI if the tagged instruction causes an L3
miss. Samples without an L3 miss are discarded and counter is reset
with random value (between 1-15 for fetch pmu and 1-127 for op pmu).
This helps in reducing sampling overhead when user is interested only
in such samples. One of the use case of such filtered samples is to
feed data to page-migration daemon in tiered memory systems.

Add support for L3 miss filtering in IBS driver via new pmu attribute
"l3missonly". Example usage:

  # perf record -a -e ibs_op/l3missonly=1/ --raw-samples sleep 5

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220509044914.1473-4-ravi.bangoria@amd.com
2022-05-11 16:27:10 +02:00
Ravi Bangoria
2a7a7e6586 perf/amd/ibs: Use ->is_visible callback for dynamic attributes
Currently, some attributes are added at build time whereas others
at boot time depending on IBS pmu capabilities. Instead, we can
just add all attribute groups at build time but hide individual
group at boot time using more appropriate ->is_visible() callback.

Also, struct perf_ibs has bunch of fields for pmu attributes which
just pass on the pointer, does not do anything else. Remove them.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220509044914.1473-3-ravi.bangoria@amd.com
2022-05-11 16:27:09 +02:00
Ravi Bangoria
39b2ca75ee perf/amd/ibs: Cascade pmu init functions' return value
IBS pmu initialization code ignores return value provided by
callee functions. Fix it.

Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20220509044914.1473-2-ravi.bangoria@amd.com
2022-05-11 16:27:09 +02:00
Ravi Bangoria
3d47083b9f perf/amd/ibs: Use interrupt regs ip for stack unwinding
IbsOpRip is recorded when IBS interrupt is triggered. But there is
a skid from the time IBS interrupt gets triggered to the time the
interrupt is presented to the core. Meanwhile processor would have
moved ahead and thus IbsOpRip will be inconsistent with rsp and rbp
recorded as part of the interrupt regs. This causes issues while
unwinding stack using the ORC unwinder as it needs consistent rip,
rsp and rbp. Fix this by using rip from interrupt regs instead of
IbsOpRip for stack unwinding.

Fixes: ee9f8fce99640 ("x86/unwind: Add the ORC unwinder")
Reported-by: Dmitry Monakhov <dmtrmonakhov@yandex-team.ru>
Suggested-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Ravi Bangoria <ravi.bangoria@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/20220429051441.14251-1-ravi.bangoria@amd.com
2022-05-10 11:00:45 +02:00
Sandipan Das
7685665c39 perf/x86/amd/core: Add PerfMonV2 overflow handling
If AMD Performance Monitoring Version 2 (PerfMonV2) is
supported, use a new scheme to process Core PMC overflows
in the NMI handler using the new global control and status
registers. This will be bypassed on unsupported hardware
(x86_pmu.version < 2).

In x86_pmu_handle_irq(), overflows are detected by testing
the contents of the PERF_CTR register for each active PMC in
a loop. The new scheme instead inspects the overflow bits of
the global status register.

The Performance Counter Global Status (PerfCntrGlobalStatus)
register has overflow (PerfCntrOvfl) bits for each PMC. This
is, however, a read-only MSR. To acknowledge that overflows
have been processed, the NMI handler must clear the bits by
writing to the PerfCntrGlobalStatusClr register.

In x86_pmu_handle_irq(), PMCs counting the same event that
are started and stopped at the same time record slightly
different counts due to delays in between reads from the
PERF_CTR registers. This is fixed by stopping and starting
the PMCs at the same before and with a single write to the
Performance Counter Global Control (PerfCntrGlobalCtl) upon
entering and before exiting the NMI handler.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/f20b7e4da0b0a83bdbe05857f354146623bc63ab.1650515382.git.sandipan.das@amd.com
2022-05-04 11:18:27 +02:00
Sandipan Das
9622e67e39 perf/x86/amd/core: Add PerfMonV2 counter control
If AMD Performance Monitoring Version 2 (PerfMonV2) is
supported, use a new scheme to manage the Core PMCs using
the new global control and status registers. This will be
bypassed on unsupported hardware (x86_pmu.version < 2).

Currently, all PMCs have dedicated control (PERF_CTL) and
counter (PERF_CTR) registers. For a given PMC, the enable
(En) bit of its PERF_CTL register is used to start or stop
counting.

The Performance Counter Global Control (PerfCntrGlobalCtl)
register has enable (PerfCntrEn) bits for each PMC. For a
PMC to start counting, both PERF_CTL and PerfCntrGlobalCtl
enable bits must be set. If either of those are cleared,
the PMC stops counting.

In x86_pmu_{en,dis}able_all(), the PERF_CTL registers of
all active PMCs are written to in a loop. Ideally, PMCs
counting the same event that were started and stopped at
the same time should record the same counts. Due to delays
in between writes to the PERF_CTL registers across loop
iterations, the PMCs cannot be enabled or disabled at the
same instant and hence, record slightly different counts.
This is fixed by enabling or disabling all active PMCs at
the same time with a single write to the PerfCntrGlobalCtl
register.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/dfe8e934074aaabc6ba748dfaccd0a77c974bb82.1650515382.git.sandipan.das@amd.com
2022-05-04 11:18:27 +02:00
Sandipan Das
56e026a7ca perf/x86/amd/core: Detect available counters
If AMD Performance Monitoring Version 2 (PerfMonV2) is
supported, use CPUID leaf 0x80000022 EBX to detect the
number of Core PMCs. This offers more flexibility if the
counts change in later processor families.

Signed-off-by: Sandipan Das <sandipan.das@amd.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lkml.kernel.org/r/68a6d9688df189267db26530378870edd34f7b06.1650515382.git.sandipan.das@amd.com
2022-05-04 11:18:26 +02:00