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commit ea142e590aec55ba40c5affb4d49e68c713c63dc upstream.
When the PMU is disabled, MMCRA is not updated to disable BHRB and
instruction sampling. This can lead to those features remaining enabled,
which can slow down a real or emulated CPU.
Fixes: 1cade527f6e9 ("powerpc/perf: BHRB control to disable BHRB logic when not used")
Cc: stable@vger.kernel.org # v5.9+
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20231018153423.298373-1-npiggin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 007240d59c11f87ac4f6cfc6a1d116630b6b634c ]
The macro __SPIN_LOCK_INITIALIZER() is implementation specific. Users
that desire to initialize a spinlock in a struct must use
__SPIN_LOCK_UNLOCKED().
Use __SPIN_LOCK_UNLOCKED() for the spinlock_t in imc_global_refc.
Fixes: 76d588dddc459 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section")
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230309134831.Nz12nqsU@linutronix.de
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 4ff3ba4db5943cac1045e3e4a3c0463ea10f6930 ]
Valid domain value is in range 1 to HV_PERF_DOMAIN_MAX. Current code has
check for domain value greater than or equal to HV_PERF_DOMAIN_MAX. But
the check for domain value 0 is missing.
Fix this issue by adding check for domain value 0.
Before:
# ./perf stat -v -e hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ sleep 1
Using CPUID 00800200
Control descriptor is not initialized
Error:
The sys_perf_event_open() syscall returned with 5 (Input/output error) for
event (hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/).
/bin/dmesg | grep -i perf may provide additional information.
Result from dmesg:
[ 37.819387] hv-24x7: hcall failed: [0 0x60040000 0x100 0] => ret
0xfffffffffffffffc (-4) detail=0x2000000 failing ix=0
After:
# ./perf stat -v -e hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ sleep 1
Using CPUID 00800200
Control descriptor is not initialized
Warning:
hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/ event is not supported by the kernel.
failed to read counter hv_24x7/CPM_ADJUNCT_INST,domain=0,core=1/
Fixes: ebd4a5a3ebd9 ("powerpc/perf/hv-24x7: Minor improvements")
Reported-by: Krishan Gopal Sarawast <krishang@linux.vnet.ibm.com>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Tested-by: Disha Goel <disgoel@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/20230825055601.360083-1-kjain@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 34daf445f82bd3a4df852bb5f1dffd792ac830a0 ]
CC arch/powerpc/perf/core-fsl-emb.o
arch/powerpc/perf/core-fsl-emb.c:675:6: error: no previous prototype for 'hw_perf_event_setup' [-Werror=missing-prototypes]
675 | void hw_perf_event_setup(int cpu)
| ^~~~~~~~~~~~~~~~~~~
Looks like fsl_emb was completely missed by commit 3f6da3905398 ("perf:
Rework and fix the arch CPU-hotplug hooks")
So, apply same changes as commit 3f6da3905398 ("perf: Rework and fix
the arch CPU-hotplug hooks") then commit 57ecde42cc74 ("powerpc/perf:
Convert book3s notifier to state machine callbacks")
While at it, also fix following error:
arch/powerpc/perf/core-fsl-emb.c: In function 'perf_event_interrupt':
arch/powerpc/perf/core-fsl-emb.c:648:13: error: variable 'found' set but not used [-Werror=unused-but-set-variable]
648 | int found = 0;
| ^~~~~
Fixes: 3f6da3905398 ("perf: Rework and fix the arch CPU-hotplug hooks")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/603e1facb32608f88f40b7d7b9094adc50e7b2dc.1692349125.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit e7299f961fe5e4496db0bfaa9e819f5e97f3846b ]
Unlike PVR_POWER8, etc ...., PVR_7450 represents a full PVR
value and not a family value.
To avoid confusion, do like E500 family and define the relevant
PVR_VER_xxxx values for the 7450 family:
0x8000 ==> 7450
0x8001 ==> 7455
0x8002 ==> 7447
0x8003 ==> 7447A
0x8004 ==> 7448
And use them to detect 7450 family for perf events.
Reported-by: kernel test robot <lkp@intel.com>
Reported-by: Dan Carpenter <error27@gmail.com>
Link: https://lore.kernel.org/r/202302260657.7dM9Uwev-lkp@intel.com/
Fixes: ec3eb9d941a9 ("powerpc/perf: Use PVR rather than oprofile field to determine CPU version")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://msgid.link/99ca1da2e5a6cf82a8abf4bc034918e500e31781.1677513277.git.christophe.leroy@csgroup.eu
Signed-off-by: Sasha Levin <sashal@kernel.org>
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commit ad53db4acb415976761d7302f5b02e97f2bd097e upstream.
The recent commit 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in
IRQs disabled section") fixed warnings (and possible deadlocks) in the
IMC PMU driver by converting the locking to use spinlocks.
It also converted the init-time nest_init_lock to a spinlock, even
though it's not used at runtime in IRQ disabled sections or while
holding other spinlocks.
This leads to warnings such as:
BUG: sleeping function called from invalid context at include/linux/percpu-rwsem.h:49
in_atomic(): 1, irqs_disabled(): 0, non_block: 0, pid: 1, name: swapper/0
preempt_count: 1, expected: 0
CPU: 7 PID: 1 Comm: swapper/0 Not tainted 6.2.0-rc2-14719-gf12cd06109f4-dirty #1
Hardware name: Mambo,Simulated-System POWER9 0x4e1203 opal:v6.6.6 PowerNV
Call Trace:
dump_stack_lvl+0x74/0xa8 (unreliable)
__might_resched+0x178/0x1a0
__cpuhp_setup_state+0x64/0x1e0
init_imc_pmu+0xe48/0x1250
opal_imc_counters_probe+0x30c/0x6a0
platform_probe+0x78/0x110
really_probe+0x104/0x420
__driver_probe_device+0xb0/0x170
driver_probe_device+0x58/0x180
__driver_attach+0xd8/0x250
bus_for_each_dev+0xb4/0x140
driver_attach+0x34/0x50
bus_add_driver+0x1e8/0x2d0
driver_register+0xb4/0x1c0
__platform_driver_register+0x38/0x50
opal_imc_driver_init+0x2c/0x40
do_one_initcall+0x80/0x360
kernel_init_freeable+0x310/0x3b8
kernel_init+0x30/0x1a0
ret_from_kernel_thread+0x5c/0x64
Fix it by converting nest_init_lock back to a mutex, so that we can call
sleeping functions while holding it. There is no interaction between
nest_init_lock and the runtime spinlocks used by the actual PMU routines.
Fixes: 76d588dddc45 ("powerpc/imc-pmu: Fix use of mutex in IRQs disabled section")
Tested-by: Kajol Jain<kjain@linux.ibm.com>
Reviewed-by: Kajol Jain<kjain@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230130014401.540543-1-mpe@ellerman.id.au
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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commit 76d588dddc459fefa1da96e0a081a397c5c8e216 upstream.
Current imc-pmu code triggers a WARNING with CONFIG_DEBUG_ATOMIC_SLEEP
and CONFIG_PROVE_LOCKING enabled, while running a thread_imc event.
Command to trigger the warning:
# perf stat -e thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/ sleep 5
Performance counter stats for 'sleep 5':
0 thread_imc/CPM_CS_FROM_L4_MEM_X_DPTEG/
5.002117947 seconds time elapsed
0.000131000 seconds user
0.001063000 seconds sys
Below is snippet of the warning in dmesg:
BUG: sleeping function called from invalid context at kernel/locking/mutex.c:580
in_atomic(): 1, irqs_disabled(): 1, non_block: 0, pid: 2869, name: perf-exec
preempt_count: 2, expected: 0
4 locks held by perf-exec/2869:
#0: c00000004325c540 (&sig->cred_guard_mutex){+.+.}-{3:3}, at: bprm_execve+0x64/0xa90
#1: c00000004325c5d8 (&sig->exec_update_lock){++++}-{3:3}, at: begin_new_exec+0x460/0xef0
#2: c0000003fa99d4e0 (&cpuctx_lock){-...}-{2:2}, at: perf_event_exec+0x290/0x510
#3: c000000017ab8418 (&ctx->lock){....}-{2:2}, at: perf_event_exec+0x29c/0x510
irq event stamp: 4806
hardirqs last enabled at (4805): [<c000000000f65b94>] _raw_spin_unlock_irqrestore+0x94/0xd0
hardirqs last disabled at (4806): [<c0000000003fae44>] perf_event_exec+0x394/0x510
softirqs last enabled at (0): [<c00000000013c404>] copy_process+0xc34/0x1ff0
softirqs last disabled at (0): [<0000000000000000>] 0x0
CPU: 36 PID: 2869 Comm: perf-exec Not tainted 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
Call Trace:
dump_stack_lvl+0x98/0xe0 (unreliable)
__might_resched+0x2f8/0x310
__mutex_lock+0x6c/0x13f0
thread_imc_event_add+0xf4/0x1b0
event_sched_in+0xe0/0x210
merge_sched_in+0x1f0/0x600
visit_groups_merge.isra.92.constprop.166+0x2bc/0x6c0
ctx_flexible_sched_in+0xcc/0x140
ctx_sched_in+0x20c/0x2a0
ctx_resched+0x104/0x1c0
perf_event_exec+0x340/0x510
begin_new_exec+0x730/0xef0
load_elf_binary+0x3f8/0x1e10
...
do not call blocking ops when !TASK_RUNNING; state=2001 set at [<00000000fd63e7cf>] do_nanosleep+0x60/0x1a0
WARNING: CPU: 36 PID: 2869 at kernel/sched/core.c:9912 __might_sleep+0x9c/0xb0
CPU: 36 PID: 2869 Comm: sleep Tainted: G W 6.2.0-rc2-00011-g1247637727f2 #61
Hardware name: 8375-42A POWER9 0x4e1202 opal:v7.0-16-g9b85f7d961 PowerNV
NIP: c000000000194a1c LR: c000000000194a18 CTR: c000000000a78670
REGS: c00000004d2134e0 TRAP: 0700 Tainted: G W (6.2.0-rc2-00011-g1247637727f2)
MSR: 9000000000021033 <SF,HV,ME,IR,DR,RI,LE> CR: 48002824 XER: 00000000
CFAR: c00000000013fb64 IRQMASK: 1
The above warning triggered because the current imc-pmu code uses mutex
lock in interrupt disabled sections. The function mutex_lock()
internally calls __might_resched(), which will check if IRQs are
disabled and in case IRQs are disabled, it will trigger the warning.
Fix the issue by changing the mutex lock to spinlock.
Fixes: 8f95faaac56c ("powerpc/powernv: Detect and create IMC device")
Reported-by: Michael Petlan <mpetlan@redhat.com>
Reported-by: Peter Zijlstra <peterz@infradead.org>
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
[mpe: Fix comments, trim oops in change log, add reported-by tags]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20230106065157.182648-1-kjain@linux.ibm.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
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[ Upstream commit 03f7c1d2a49acd30e38789cd809d3300721e9b0e ]
Based on getPerfCountInfo v1.018 documentation, some of the
hv_gpci events were deprecated for platform firmware that
supports counter_info_version 0x8 or above.
Fix the hv_gpci event list by adding a new attribute group
called "hv_gpci_event_attrs_v6" and a "ENABLE_EVENTS_COUNTERINFO_V6"
macro to enable these events for platform firmware
that supports counter_info_version 0x6 or below. And assigning
the hv_gpci event list based on output counter info version
of underlying plaform.
Fixes: 97bf2640184f ("powerpc/perf/hv-gpci: add the remaining gpci requests")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221130174513.87501-1-kjain@linux.ibm.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
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[ Upstream commit 32c5209214bd8d4f8c4e9d9b630ef4c671f58e79 ]
The interrupt frame detection and loads from the hypothetical pt_regs
are not bounds-checked. The next-frame validation only bounds-checks
STACK_FRAME_OVERHEAD, which does not include the pt_regs. Add another
test for this.
The user could set r1 to be equal to the address matching the first
interrupt frame - STACK_INT_FRAME_SIZE, which is in the previous page
due to the kernel redzone, and induce the kernel to load the marker from
there. Possibly this could cause a crash at least. If the user could
induce the previous page to contain a valid marker, then it might be
able to direct perf to read specific memory addresses in a way that
could be transmitted back to the user in the perf data.
Fixes: 20002ded4d93 ("perf_counter: powerpc: Add callchain support")
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20221127124942.1665522-4-npiggin@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
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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
...
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For PERF_SAMPLE_BRANCH_STACK sample type, different branch_sample_type
ie branch filters are supported. The branch filters are requested via
event attribute "branch_sample_type". Multiple branch filters can be
passed in event attribute. eg:
$ perf record -b -o- -B --branch-filter any,ind_call true
None of the Power PMUs support having multiple branch filters at
the same time. Branch filters for branch stack sampling is set via MMCRA
IFM bits [32:33]. But currently when requesting for multiple filter
types, the "perf record" command does not report any error.
eg:
$ perf record -b -o- -B --branch-filter any,save_type true
$ perf record -b -o- -B --branch-filter any,ind_call true
The "bhrb_filter_map" function in PMU driver code does the validity
check for supported branch filters. But this check is done for single
filter. Hence "perf record" will proceed here without reporting any
error.
Fix power_pmu_event_init() to return EOPNOTSUPP when multiple branch
filters are requested in the event attr.
After the fix:
$ perf record --branch-filter any,ind_call -- ls
Error:
cycles: PMU Hardware doesn't support sampling/overflow-interrupts.
Try 'perf stat'
Reported-by: Disha Goel <disgoel@linux.vnet.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Disha Goel<disgoel@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Reviewed-by: Kajol Jain <kjain@linux.ibm.com>
[mpe: Tweak comment and change log wording]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220921145255.20972-1-atrajeev@linux.vnet.ibm.com
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Use helper macros to access global variables, and place them in .data
sections rather than in .toc. Putting addresses in TOC is not required
because the kernel is linked with a single TOC.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220926034057.2360083-3-npiggin@gmail.com
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Forward declare all syscall handler prototypes where a generic prototype
is not provided in either linux/syscalls.h or linux/compat.h in
asm/syscalls.h. This is required for compile-time type-checking for
syscall handlers, which is implemented later in this series.
32-bit compatibility syscall handlers are expressed in terms of types in
ppc32.h. Expose this header globally.
Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Acked-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Use standard include guard naming for syscalls_32.h]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220921065605.1051927-17-rmclure@linux.ibm.com
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Use the new sample_flags to indicate whether the data_src field is
filled by the PMU driver.
Remove the data_src field 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/20220901130959.1285717-6-kan.liang@linux.intel.com
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Use the new sample_flags to indicate whether the weight field is filled
by the PMU driver.
Remove the weight field 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/20220901130959.1285717-5-kan.liang@linux.intel.com
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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
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In update_events_in_group(), of_find_node_by_phandle() will return
a node pointer with refcount incremented. The reference should be
dropped with of_node_put() in the failure path or when it is not used
anymore.
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Link: https://lore.kernel.org/r/20220618071353.4059000-1-windhl@126.com
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Commit 6320e693d98c ("powerpc/perf: Add support for caps under sysfs in
powerpc") added support for caps under sysfs in powerpc. This added caps
directory to: /sys/bus/event_source/devices/cpu/ for power8, power9,
power10 and generic compat PMU in respective PMU driver code.
For power10, it is added under "power10_pmu_attr_groups". But
for DD1 version, attr_groups are defined under dd1 array:
"power10_pmu_attr_groups_dd1". Since caps is not added for DD1,
it fails to include "cpu/caps" in DD1 model.
The issue was observed while booting power10 pseries with qemu version
6, but not observed with qemu version 7. This is because qemu version 7
uses a DD 2.0 CPU model.
Below is the trace log:
Can't update unknown attr grp name: cpu/caps^M
------------[ cut here ]------------^M
Failed to register pmu: cpu, reason -22^M
WARNING: CPU: 1 PID: 1 at kernel/events/core.c:13427 perf_event_sysfs_init+0xbc/0x108^M
Modules linked in:^M
CPU: 1 PID: 1 Comm: swapper/0 Not tainted 5.19.0-rc2-00111-g6320e693d98c #148^M
NIP: c0000000020391f4 LR: c0000000020391f0 CTR: c0000000008c9c30^M
REGS: c0000000044c38c0 TRAP: 0700 Not tainted (5.19.0-rc2-00111-g6320e693d98c)^M
MSR: 8000000002029033 <SF,VEC,EE,ME,IR,DR,RI,LE> CR: 48000281 XER: 20040000^M
CFAR: c00000000013feac IRQMASK: 0 ^M
GPR00: c0000000020391f0 c0000000044c3b60 c00000000283db00 0000000000000027 ^M
GPR04: 80000000ffffe0a8 0000000000000000 0000000000000004 00000000fdcd0000 ^M
GPR08: 0000000000000027 c0000000ffe07e08 0000000000000001 0000000000000000 ^M
GPR12: c00000000035dd90 c0000000fffff300 c000000000012478 0000000000000000 ^M
GPR16: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ^M
GPR20: 0000000000000000 0000000000000000 0000000000000000 0000000000000000 ^M
GPR24: c000000002003480 0000000000000007 c0000000012a78d0 c000000001170a80 ^M
GPR28: c0000000026c4df8 c0000000026c4e68 0000000000000000 c0000000025a8628 ^M
NIP [c0000000020391f4] perf_event_sysfs_init+0xbc/0x108^M
LR [c0000000020391f0] perf_event_sysfs_init+0xb8/0x108^M
Call Trace:^M
[c0000000044c3b60] [c0000000020391f0] perf_event_sysfs_init+0xb8/0x108 (unreliable)^M
[c0000000044c3bf0] [c000000000011ec4] do_one_initcall+0x64/0x2d0^M
[c0000000044c3cd0] [c0000000020049fc] kernel_init_freeable+0x338/0x3e0^M
[c0000000044c3db0] [c0000000000124a0] kernel_init+0x30/0x1a0^M
[c0000000044c3e10] [c00000000000cd54] ret_from_kernel_thread+0x5c/0x64^M
Instruction dump:^M
813f0038 2c090000 4180002c 7fe3fb78 4a3280c5 2c030000 7c651b78 41820018 ^M
e89f0030 7f63db78 4a106c59 60000000 <0fe00000> ebff0000 4bffffb4 39200001 ^M
---[ end trace 0000000000000000 ]---^M
Fix it by adding caps for dd1 attr_groups in power10 PMU driver.
Fixes: 6320e693d98c ("powerpc/perf: Add support for caps under sysfs in powerpc")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
[mpe: Update change log to mention qemu 7 DD2.0 CPU model]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220728163746.85062-1-atrajeev@linux.vnet.ibm.com
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Currently the perf CPU backend drivers detect what CPU they're on using
cur_cpu_spec->oprofile_cpu_type.
Although that works, it's a bit crufty to be using oprofile related fields,
especially seeing as oprofile is more or less unused these days.
It also means perf is reliant on the fragile logic in setup_cpu_spec()
which detects when we're using a logical PVR and copies back the PMU
related fields from the raw CPU entry. So lets check the PVR directly.
Suggested-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Rashmica Gupta <rashmica.g@gmail.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
[chleroy: Added power10 and fixed checkpatch issues]
Reviewed-and-tested-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-and-tested-By: Kajol Jain <kjain@linux.ibm.com> [For 24x7 side changes]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20c0ee7f99dbf0dbf8658df6b39f84753e6db1ef.1657204631.git.christophe.leroy@csgroup.eu
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Add caps support under "/sys/bus/event_source/devices/<pmu>/"
for powerpc. This directory can be used to expose some of the
specific features that powerpc PMU supports to the user.
Example: pmu_name. The name of PMU registered will depend on
platform, say power9 or power10 or it could be Generic Compat
PMU.
Currently the only way to know which is the registered
PMU is from the dmesg logs. But clearing the dmesg will make it
difficult to know exact PMU backend used. And even extracting
from dmesg will be complicated, as we need to parse the dmesg
logs and add filters for pmu name. Whereas by exposing it via
caps will make it easy as we just need to directly read it from
the sysfs.
Add a caps directory to /sys/bus/event_source/devices/cpu/
for power8, power9, power10 and generic compat PMU in respective
PMU driver code. Update the pmu_name file under caps folder
in core-book3s using "attr_update".
The information exposed currently:
- pmu_name : Underlying PMU name from the driver
Example result with power9 pmu:
# ls /sys/bus/event_source/devices/cpu/caps
pmu_name
# cat /sys/bus/event_source/devices/cpu/caps/pmu_name
POWER9
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220520084630.15181-1-atrajeev@linux.vnet.ibm.com
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When booting on a machine that uses the compat pmu driver we see this:
[ 0.071192] GENERIC_COMPAT performance monitor hardware support registered
Which is a bit shouty. Give it a nicer name.
Signed-off-by: Joel Stanley <joel@jms.id.au>
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220610044006.2095806-1-joel@jms.id.au
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struct perf_event_attr supports exclude counting of idle task.
This is sent to kernel via perf_event_attr.exclude_idle and
in perf tool, user can use ":I" event modifier to enable this
for specific event.
Monitor Mode Control Register 2 (MMCR2) SPR has control bits
for each PMCs to freeze counting based on the Control Register
CTRL[RUN] state. CTRL[RUN] is not set when idle task is
running. Patch adds a check for event attr.exclude_idle to
set MMCR2[FCnWAIT] bit.
Signed-off-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210429050208.266619-1-maddy@linux.ibm.com
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check in power_pmu_disable
commit 2c9ac51b850d ("powerpc/perf: Fix PMU callbacks to clear
pending PMI before resetting an overflown PMC") added a new
function "pmi_irq_pending" in hw_irq.h. This function is to check
if there is a PMI marked as pending in Paca (PACA_IRQ_PMI).This is
used in power_pmu_disable in a WARN_ON. The intention here is to
provide a warning if there is PMI pending, but no counter is found
overflown.
During some of the perf runs, below warning is hit:
WARNING: CPU: 36 PID: 0 at arch/powerpc/perf/core-book3s.c:1332 power_pmu_disable+0x25c/0x2c0
Modules linked in:
-----
NIP [c000000000141c3c] power_pmu_disable+0x25c/0x2c0
LR [c000000000141c8c] power_pmu_disable+0x2ac/0x2c0
Call Trace:
[c000000baffcfb90] [c000000000141c8c] power_pmu_disable+0x2ac/0x2c0 (unreliable)
[c000000baffcfc10] [c0000000003e2f8c] perf_pmu_disable+0x4c/0x60
[c000000baffcfc30] [c0000000003e3344] group_sched_out.part.124+0x44/0x100
[c000000baffcfc80] [c0000000003e353c] __perf_event_disable+0x13c/0x240
[c000000baffcfcd0] [c0000000003dd334] event_function+0xc4/0x140
[c000000baffcfd20] [c0000000003d855c] remote_function+0x7c/0xa0
[c000000baffcfd50] [c00000000026c394] flush_smp_call_function_queue+0xd4/0x300
[c000000baffcfde0] [c000000000065b24] smp_ipi_demux_relaxed+0xa4/0x100
[c000000baffcfe20] [c0000000000cb2b0] xive_muxed_ipi_action+0x20/0x40
[c000000baffcfe40] [c000000000207c3c] __handle_irq_event_percpu+0x8c/0x250
[c000000baffcfee0] [c000000000207e2c] handle_irq_event_percpu+0x2c/0xa0
[c000000baffcff10] [c000000000210a04] handle_percpu_irq+0x84/0xc0
[c000000baffcff40] [c000000000205f14] generic_handle_irq+0x54/0x80
[c000000baffcff60] [c000000000015740] __do_irq+0x90/0x1d0
[c000000baffcff90] [c000000000016990] __do_IRQ+0xc0/0x140
[c0000009732f3940] [c000000bafceaca8] 0xc000000bafceaca8
[c0000009732f39d0] [c000000000016b78] do_IRQ+0x168/0x1c0
[c0000009732f3a00] [c0000000000090c8] hardware_interrupt_common_virt+0x218/0x220
This means that there is no PMC overflown among the active events
in the PMU, but there is a PMU pending in Paca. The function
"any_pmc_overflown" checks the PMCs on active events in
cpuhw->n_events. Code snippet:
<<>>
if (any_pmc_overflown(cpuhw))
clear_pmi_irq_pending();
else
WARN_ON(pmi_irq_pending());
<<>>
Here the PMC overflown is not from active event. Example: When we do
perf record, default cycles and instructions will be running on PMC6
and PMC5 respectively. It could happen that overflowed event is currently
not active and pending PMI is for the inactive event. Debug logs from
trace_printk:
<<>>
any_pmc_overflown: idx is 5: pmc value is 0xd9a
power_pmu_disable: PMC1: 0x0, PMC2: 0x0, PMC3: 0x0, PMC4: 0x0, PMC5: 0xd9a, PMC6: 0x80002011
<<>>
Here active PMC (from idx) is PMC5 , but overflown PMC is PMC6(0x80002011).
When we handle PMI interrupt for such cases, if the PMC overflown is
from inactive event, it will be ignored. Reference commit:
commit bc09c219b2e6 ("powerpc/perf: Fix finding overflowed PMC in interrupt")
Patch addresses two changes:
1) Fix 1 : Removal of warning ( WARN_ON(pmi_irq_pending()); )
We were printing warning if no PMC is found overflown among active PMU
events, but PMI pending in PACA. But this could happen in cases where
PMC overflown is not in active PMC. An inactive event could have caused
the overflow. Hence the warning is not needed. To know pending PMI is
from an inactive event, we need to loop through all PMC's which will
cause more SPR reads via mfspr and increase in context switch. Also in
existing function: perf_event_interrupt, already we ignore PMI's
overflown when it is from an inactive PMC.
2) Fix 2: optimization in clearing pending PMI.
Currently we check for any active PMC overflown before clearing PMI
pending in Paca. This is causing additional SPR read also. From point 1,
we know that if PMI pending in Paca from inactive cases, that is going
to be ignored during replay. Hence if there is pending PMI in Paca, just
clear it irrespective of PMC overflown or not.
In summary, remove the any_pmc_overflown check entirely in
power_pmu_disable. ie If there is a pending PMI in Paca, clear it, since
we are in pmu_disable. There could be cases where PMI is pending because
of inactive PMC ( which later when replayed also will get ignored ), so
WARN_ON could give false warning. Hence removing it.
Fixes: 2c9ac51b850d ("powerpc/perf: Fix PMU callbacks to clear pending PMI before resetting an overflown PMC")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220522142256.24699-1-atrajeev@linux.vnet.ibm.com
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Thresh compare bits for a event is used to program thresh compare
field in Monitor Mode Control Register A (MMCRA: 9-18 bits for power9).
When scheduling events as a group, all events in that group should
match value in threshold bits (like thresh compare, thresh control,
thresh select). Otherwise event open for the sibling events should fail.
But in the current code, incase thresh compare bits are not valid,
we are not failing in group_constraint function which can result
in invalid group schduling.
Fix the issue by returning -1 incase event is threshold and threshold
compare value is not valid.
Thresh control bits in the event code is used to program thresh_ctl
field in Monitor Mode Control Register A (MMCRA: 48-55). In below example,
the scheduling of group events PM_MRK_INST_CMPL (873534401e0) and
PM_THRESH_MET (8734340101ec) is expected to fail as both event
request different thresh control bits and invalid thresh compare value.
Result before the patch changes:
[command]# perf stat -e "{r8735340401e0,r8734340101ec}" sleep 1
Performance counter stats for 'sleep 1':
11,048 r8735340401e0
1,967 r8734340101ec
1.001354036 seconds time elapsed
0.001421000 seconds user
0.000000000 seconds sys
Result after the patch changes:
[command]# perf stat -e "{r8735340401e0,r8734340101ec}" sleep 1
Error:
The sys_perf_event_open() syscall returned with 22 (Invalid argument)
for event (r8735340401e0).
/bin/dmesg | grep -i perf may provide additional information.
Fixes: 78a16d9fc1206 ("powerpc/perf: Avoid FAB_*_MATCH checks for power9")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220506061015.43916-2-kjain@linux.ibm.com
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Thresh compare bits for a event is used to program thresh compare
field in Monitor Mode Control Register A (MMCRA: 8-18 bits for power10).
When scheduling events as a group, all events in that group should
match value in threshold bits. Otherwise event open for the sibling
events should fail. But in the current code, incase thresh compare bits are
not valid, we are not failing in group_constraint function which can result
in invalid group schduling.
Fix the issue by returning -1 incase event is threshold and threshold
compare value is not valid in group_constraint function.
Patch also fixes the p10_thresh_cmp_val function to return -1,
incase threshold bits are not valid and changes corresponding check in
is_thresh_cmp_valid function to return false only when the thresh_cmp
value is less then 0.
Thresh control bits in the event code is used to program thresh_ctl
field in Monitor Mode Control Register A (MMCRA: 48-55). In below example,
the scheduling of group events PM_MRK_INST_CMPL (3534401e0) and
PM_THRESH_MET (34340101ec) is expected to fail as both event
request different thresh control bits.
Result before the patch changes:
[command]# perf stat -e "{r35340401e0,r34340101ec}" sleep 1
Performance counter stats for 'sleep 1':
8,482 r35340401e0
0 r34340101ec
1.001474838 seconds time elapsed
0.001145000 seconds user
0.000000000 seconds sys
Result after the patch changes:
[command]# perf stat -e "{r35340401e0,r34340101ec}" sleep 1
Performance counter stats for 'sleep 1':
<not counted> r35340401e0
<not supported> r34340101ec
1.001499607 seconds time elapsed
0.000204000 seconds user
0.000760000 seconds sys
Fixes: 82d2c16b350f7 ("powerpc/perf: Adds support for programming of Thresholding in P10")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220506061015.43916-1-kjain@linux.ibm.com
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Don't inherit headers "by chances" from asm/prom.h, asm/mpc52xx.h,
asm/pci.h etc...
Include the needed headers, and remove asm/prom.h when it was
needed exclusively for pulling necessary headers.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/be8bdc934d152a7d8ee8d1a840d5596e2f7d85e0.1646767214.git.christophe.leroy@csgroup.eu
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Various spelling mistakes in comments.
Detected with the help of Coccinelle.
Signed-off-by: Julia Lawall <Julia.Lawall@inria.fr>
Reviewed-by: Joel Stanley <joel@jms.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220430185654.5855-1-Julia.Lawall@inria.fr
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Merge master into next, to bring in commit 5f24d5a579d1 ("mm, hugetlb:
allow for "high" userspace addresses"), which is needed as a
prerequisite for the series converting powerpc to the generic mmap
logic.
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Replace the 'unsigned' with 'unsigned int' which is more accurate.
Signed-off-by: Jason Wang <wangborong@cdjrlc.com>
[chleroy: Fixed parenthesis alignment]
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210729115252.40895-1-wangborong@cdjrlc.com
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Build kernel with `C=2`:
arch/powerpc/perf/isa207-common.c:24:18: warning: symbol
'isa207_pmu_format_attr' was not declared. Should it be static?
arch/powerpc/perf/power9-pmu.c:101:5: warning: symbol 'p9_dd21_bl_ev'
was not declared. Should it be static?
arch/powerpc/perf/power9-pmu.c:115:5: warning: symbol 'p9_dd22_bl_ev'
was not declared. Should it be static?
Those symbols are used only in the files that define them so we declare
them as static to fix the warnings.
Signed-off-by: Wang Wensheng <wangwensheng4@huawei.com>
Reviewed-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200923071453.2540-1-wangwensheng4@huawei.com
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The "read_bhrb" global symbol is only called under CONFIG_PPC64 of
arch/powerpc/perf/core-book3s.c but it is compiled for both 32 and 64 bit
anyway (and LLVM fails to link this on 32bit).
This fixes it by moving bhrb.o to obj64 targets.
Signed-off-by: Alexey Kardashevskiy <aik@ozlabs.ru>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220421025756.571995-1-aik@ozlabs.ru
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When scheduling a group of events, there are constraint checks done to
make sure all events can go in a group. Example, one of the criteria is
that events in a group cannot use the same PMC. But platform specific
PMU supports alternative event for some of the event codes. During
perf_event_open(), if any event group doesn't match constraint check
criteria, further lookup is done to find alternative event.
By current design, the array of alternatives events in PMU code is
expected to be sorted by column 0. This is because in
find_alternative() the return criteria is based on event code
comparison. ie. "event < ev_alt[i][0])". This optimisation is there
since find_alternative() can be called multiple times. In power10 PMU
code, the alternative event array is not sorted properly and hence there
is breakage in finding alternative event.
To work with existing logic, fix the alternative event array to be
sorted by column 0 for power10-pmu.c
Results:
In case where an alternative event is not chosen when we could, events
will be multiplexed. ie, time sliced where it could actually run
concurrently.
Example, in power10 PM_INST_CMPL_ALT(0x00002) has alternative event,
PM_INST_CMPL(0x500fa). Without the fix, if a group of events with PMC1
to PMC4 is used along with PM_INST_CMPL_ALT, it will be time sliced
since all programmable PMC's are consumed already. But with the fix,
when it picks alternative event on PMC5, all events will run
concurrently.
Before:
# perf stat -e r00002,r100fc,r200fa,r300fc,r400fc
Performance counter stats for 'system wide':
328668935 r00002 (79.94%)
56501024 r100fc (79.95%)
49564238 r200fa (79.95%)
376 r300fc (80.19%)
660 r400fc (79.97%)
4.039150522 seconds time elapsed
With the fix, since alternative event is chosen to run on PMC6, events
will be run concurrently.
After:
# perf stat -e r00002,r100fc,r200fa,r300fc,r400fc
Performance counter stats for 'system wide':
23596607 r00002
4907738 r100fc
2283608 r200fa
135 r300fc
248 r400fc
1.664671390 seconds time elapsed
Fixes: a64e697cef23 ("powerpc/perf: power10 Performance Monitoring support")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220419114828.89843-2-atrajeev@linux.vnet.ibm.com
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When scheduling a group of events, there are constraint checks done to
make sure all events can go in a group. Example, one of the criteria is
that events in a group cannot use the same PMC. But platform specific
PMU supports alternative event for some of the event codes. During
perf_event_open(), if any event group doesn't match constraint check
criteria, further lookup is done to find alternative event.
By current design, the array of alternatives events in PMU code is
expected to be sorted by column 0. This is because in
find_alternative() the return criteria is based on event code
comparison. ie. "event < ev_alt[i][0])". This optimisation is there
since find_alternative() can be called multiple times. In power9 PMU
code, the alternative event array is not sorted properly and hence there
is breakage in finding alternative events.
To work with existing logic, fix the alternative event array to be
sorted by column 0 for power9-pmu.c
Results:
With alternative events, multiplexing can be avoided. That is, for
example, in power9 PM_LD_MISS_L1 (0x3e054) has alternative event,
PM_LD_MISS_L1_ALT (0x400f0). This is an identical event which can be
programmed in a different PMC.
Before:
# perf stat -e r3e054,r300fc
Performance counter stats for 'system wide':
1057860 r3e054 (50.21%)
379 r300fc (49.79%)
0.944329741 seconds time elapsed
Since both the events are using PMC3 in this case, they are
multiplexed here.
After:
# perf stat -e r3e054,r300fc
Performance counter stats for 'system wide':
1006948 r3e054
182 r300fc
Fixes: 91e0bd1e6251 ("powerpc/perf: Add PM_LD_MISS_L1 and PM_BR_2PATH to power9 event list")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220419114828.89843-1-atrajeev@linux.vnet.ibm.com
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Inspired by (bd75b4ef4977: Constify static attribute_group structs),
accepted by linux-next, reported:
https://patchwork.ozlabs.org/project/linuxppc-dev/patch/20220210202805.7750-4-rikard.falkeborn@gmail.com/
Nearly all singletons of type struct attribute_group are never modified,
and so are candidates for being const. Declare them as const.
Signed-off-by: Rohan McLure <rmclure@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220307231414.86560-1-rmclure@linux.ibm.com
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Hash faults are not resoved in NMI context, instead causing the access
to fail. This is done because perf interrupts can get backtraces
including walking the user stack, and taking a hash fault on those could
deadlock on the HPTE lock if the perf interrupt hits while the same HPTE
lock is being held by the hash fault code. The user-access for the stack
walking will notice the access failed and deal with that in the perf
code.
The reason to allow perf interrupts in is to better profile hash faults.
The problem with this is any hash fault on a kernel access that happens
in NMI context will crash, because kernel accesses must not fail.
Hard lockups, system reset, machine checks that access vmalloc space
including modules and including stack backtracing and symbol lookup in
modules, per-cpu data, etc could all run into this problem.
Fix this by disallowing perf interrupts in the hash fault code (the
direct hash fault is covered by MSR[EE]=0 so the PMI disable just needs
to extend to the preload case). This simplifies the tricky logic in hash
faults and perf, at the cost of reduced profiling of hash faults.
perf can still latch addresses when interrupts are disabled, it just
won't get the stack trace at that point, so it would still find hot
spots, just sometimes with confusing stack chains.
An alternative could be to allow perf interrupts here but always do the
slowpath stack walk if we are in nmi context, but that slows down all
perf interrupt stack walking on hash though and it does not remove as
much tricky code.
Reported-by: Laurent Dufour <ldufour@linux.ibm.com>
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Tested-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220204035348.545435-1-npiggin@gmail.com
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Two places deserve using the macro is_tsk_32bit_task() added by
commit 252745240ba0 ("powerpc/audit: Fix syscall_get_arch()")
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/7304a889dbe885aefad8a8333673c81ee4b8f7a6.1642751874.git.christophe.leroy@csgroup.eu
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Trace IMC (In-Memory collection counters) in powerpc is useful for
application level profiling.
For trace_imc, presently task context (task_ctx_nr) is set to
perf_hw_context. But perf_hw_context should only be used for CPU PMU.
See commit 26657848502b ("perf/core: Verify we have a single
perf_hw_context PMU").
So for trace_imc, even though it is per thread PMU, it is preferred to
use sw_context in order to be able to do application level monitoring.
Hence change the task_ctx_nr to use perf_sw_context.
Fixes: 012ae244845f ("powerpc/perf: Trace imc PMU functions")
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.vnet.ibm.com>
[mpe: Update subject & incorporate notes into change log, reflow comment]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220202041837.65968-1-atrajeev@linux.vnet.ibm.com
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PMI is pending
Running selftest with CONFIG_PPC_IRQ_SOFT_MASK_DEBUG enabled in kernel
triggered below warning:
[ 172.851380] ------------[ cut here ]------------
[ 172.851391] WARNING: CPU: 8 PID: 2901 at arch/powerpc/include/asm/hw_irq.h:246 power_pmu_disable+0x270/0x280
[ 172.851402] Modules linked in: dm_mod bonding nft_ct nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 ip_set nf_tables rfkill nfnetlink sunrpc xfs libcrc32c pseries_rng xts vmx_crypto uio_pdrv_genirq uio sch_fq_codel ip_tables ext4 mbcache jbd2 sd_mod t10_pi sg ibmvscsi ibmveth scsi_transport_srp fuse
[ 172.851442] CPU: 8 PID: 2901 Comm: lost_exception_ Not tainted 5.16.0-rc5-03218-g798527287598 #2
[ 172.851451] NIP: c00000000013d600 LR: c00000000013d5a4 CTR: c00000000013b180
[ 172.851458] REGS: c000000017687860 TRAP: 0700 Not tainted (5.16.0-rc5-03218-g798527287598)
[ 172.851465] MSR: 8000000000029033 <SF,EE,ME,IR,DR,RI,LE> CR: 48004884 XER: 20040000
[ 172.851482] CFAR: c00000000013d5b4 IRQMASK: 1
[ 172.851482] GPR00: c00000000013d5a4 c000000017687b00 c000000002a10600 0000000000000004
[ 172.851482] GPR04: 0000000082004000 c0000008ba08f0a8 0000000000000000 00000008b7ed0000
[ 172.851482] GPR08: 00000000446194f6 0000000000008000 c00000000013b118 c000000000d58e68
[ 172.851482] GPR12: c00000000013d390 c00000001ec54a80 0000000000000000 0000000000000000
[ 172.851482] GPR16: 0000000000000000 0000000000000000 c000000015d5c708 c0000000025396d0
[ 172.851482] GPR20: 0000000000000000 0000000000000000 c00000000a3bbf40 0000000000000003
[ 172.851482] GPR24: 0000000000000000 c0000008ba097400 c0000000161e0d00 c00000000a3bb600
[ 172.851482] GPR28: c000000015d5c700 0000000000000001 0000000082384090 c0000008ba0020d8
[ 172.851549] NIP [c00000000013d600] power_pmu_disable+0x270/0x280
[ 172.851557] LR [c00000000013d5a4] power_pmu_disable+0x214/0x280
[ 172.851565] Call Trace:
[ 172.851568] [c000000017687b00] [c00000000013d5a4] power_pmu_disable+0x214/0x280 (unreliable)
[ 172.851579] [c000000017687b40] [c0000000003403ac] perf_pmu_disable+0x4c/0x60
[ 172.851588] [c000000017687b60] [c0000000003445e4] __perf_event_task_sched_out+0x1d4/0x660
[ 172.851596] [c000000017687c50] [c000000000d1175c] __schedule+0xbcc/0x12a0
[ 172.851602] [c000000017687d60] [c000000000d11ea8] schedule+0x78/0x140
[ 172.851608] [c000000017687d90] [c0000000001a8080] sys_sched_yield+0x20/0x40
[ 172.851615] [c000000017687db0] [c0000000000334dc] system_call_exception+0x18c/0x380
[ 172.851622] [c000000017687e10] [c00000000000c74c] system_call_common+0xec/0x268
The warning indicates that MSR_EE being set(interrupt enabled) when
there was an overflown PMC detected. This could happen in
power_pmu_disable since it runs under interrupt soft disable
condition ( local_irq_save ) and not with interrupts hard disabled.
commit 2c9ac51b850d ("powerpc/perf: Fix PMU callbacks to clear
pending PMI before resetting an overflown PMC") intended to clear
PMI pending bit in Paca when disabling the PMU. It could happen
that PMC gets overflown while code is in power_pmu_disable
callback function. Hence add a check to see if PMI pending bit
is set in Paca before clearing it via clear_pmi_pending.
Fixes: 2c9ac51b850d ("powerpc/perf: Fix PMU callbacks to clear pending PMI before resetting an overflown PMC")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220122033429.25395-1-atrajeev@linux.vnet.ibm.com
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power_pmu_wants_prompt_pmi() is used to decide if PMIs should be taken
promptly. This is valid only for ppc64 and is used only if
CONFIG_PPC_BOOK3S_64=y. Hence include the function under config check
for PPC64.
Fixes warning for 32-bit compilation:
arch/powerpc/perf/core-book3s.c:2455:6: warning: no previous prototype for 'power_pmu_wants_prompt_pmi'
2455 | bool power_pmu_wants_prompt_pmi(void)
| ^~~~~~~~~~~~~~~~~~~~~~~~~~
Fixes: 5a7745b96f43 ("powerpc/64s/perf: add power_pmu_wants_prompt_pmi to say whether perf wants PMIs to be soft-NMI")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Move inside existing CONFIG_PPC64 ifdef block]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20220114031355.87480-1-atrajeev@linux.vnet.ibm.com
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Use the possessive "its" instead of the contraction of "it is" (it's).
Signed-off-by: Randy Dunlap <rdunlap@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211223003942.22098-1-rdunlap@infradead.org
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Some functions defined in 'arch/powerpc/perf' are deserving of an
`__init` macro attribute. These functions are only called by other
initialization functions and therefore should inherit the attribute.
Also, change function declarations in header files to include `__init`.
Signed-off-by: Nick Child <nick.child@ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211216220035.605465-5-nick.child@ibm.com
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PMIs to be soft-NMI
Interrupt code enables MSR[EE] in some irq handlers while keeping local
irqs disabled via soft-mask, allowing PMI interrupts to be taken as
soft-NMI to improve profiling of irq handlers.
When perf is not enabled, there is no point to doing this, it's
additional overhead. So provide a function that can say if PMIs should
be taken promptly if possible.
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20210922145452.352571-4-npiggin@gmail.com
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The code represent memory/cache level data based on PERF_MEM_LVL_*
namespace, which is in the process of deprication in the favour of
newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_} fields.
Add data source encodings to represent cache/memory data based on
newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_} fields.
Add data source encodings to represent data coming from local
memory/Remote memory/distant memory and remote/distant cache hits.
In order to represent data coming from OpenCAPI cache/memory, we use
LVLNUM "PMEM" field which is used to present persistent memory accesses.
Result in power10 system with patch changes:
localhost:# ./perf mem report --sort="mem,sym,dso" --stdio
# Overhead Samples Memory access Symbol Shared Object
# ........ ............ ........................ .......................... ................
#
29.46% 2331 L1 or L1 hit [.] __random libc-2.28.so
23.11% 2121 L1 or L1 hit [.] producer_populate_cache producer_consumer
18.56% 1758 L1 or L1 hit [.] __random_r libc-2.28.so
15.64% 1559 L2 or L2 hit [.] __random libc-2.28.so
.....
0.09% 5 Remote socket, same board Any cache hit [.] __random libc-2.28.so
0.07% 4 Remote socket, same board Any cache hit [.] __random libc-2.28.so
.....
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211206091749.87585-5-kjain@linux.ibm.com
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PERF_MEM_LVLNUM* fields
The code represent data coming from L1/L2/L3 cache hits based on
PERF_MEM_LVL_* namespace, which is in the process of deprecation in
the favour of newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_}
fields.
Add data source encodings to represent L1/L2/L3 cache hits based on
newer composite PERF_MEM_{LVLNUM_,REMOTE_,SNOOPX_,HOPS_} fields for
power10 and older platforms
Result in power9 system without patch changes:
localhost:# ./perf mem report --sort="mem,sym,dso" --stdio
# Overhead Samples Memory access Symbol Shared Object
# ........ ............ ........................ ................................. ................
#
29.51% 1 L2 hit [k] perf_event_exec [kernel.vmlinux]
27.05% 1 L1 hit [k] perf_ctx_unlock [kernel.vmlinux]
13.93% 1 L1 hit [k] vtime_delta [kernel.vmlinux]
13.11% 1 L1 hit [k] prepend_path.isra.11 [kernel.vmlinux]
8.20% 1 L1 hit [.] 00000038.plt_call.__GI_strlen libc-2.28.so
8.20% 1 L1 hit [k] perf_event_interrupt [kernel.vmlinux]
Result in power9 system with patch changes:
localhost:# ./perf mem report --sort="mem,sym,dso" --stdio
# Overhead Samples Memory access Symbol Shared Object
# ........ ............ ........................ .......................... ................
#
36.63% 1 L2 or L2 hit [k] perf_event_exec [kernel.vmlinux]
25.50% 1 L1 or L1 hit [k] vtime_delta [kernel.vmlinux]
13.12% 1 L1 or L1 hit [k] unmap_region [kernel.vmlinux]
12.62% 1 L1 or L1 hit [k] perf_sample_event_took [kernel.vmlinux]
6.93% 1 L1 or L1 hit [k] perf_ctx_unlock [kernel.vmlinux]
5.20% 1 L1 or L1 hit [.] __memcpy_power7 libc-2.28.so
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Reviewed-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211206091749.87585-4-kjain@linux.ibm.com
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In order to stop using 'struct ppc_inst' on PPC32,
define a ppc_inst_t typedef.
Signed-off-by: Christophe Leroy <christophe.leroy@csgroup.eu>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/fe5baa2c66fea9db05a8b300b3e8d2880a42596c.1638208156.git.christophe.leroy@csgroup.eu
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overflown PMC
Running perf fuzzer showed below in dmesg logs:
"Can't find PMC that caused IRQ"
This means a PMU exception happened, but none of the PMC's (Performance
Monitor Counter) were found to be overflown. There are some corner cases
that clears the PMCs after PMI gets masked. In such cases, the perf
interrupt handler will not find the active PMC values that had caused
the overflow and thus leads to this message while replaying.
Case 1: PMU Interrupt happens during replay of other interrupts and
counter values gets cleared by PMU callbacks before replay:
During replay of interrupts like timer, __do_irq() and doorbell
exception, we conditionally enable interrupts via may_hard_irq_enable().
This could potentially create a window to generate a PMI. Since irq soft
mask is set to ALL_DISABLED, the PMI will get masked here. We could get
IPIs run before perf interrupt is replayed and the PMU events could
be deleted or stopped. This will change the PMU SPR values and resets
the counters. Snippet of ftrace log showing PMU callbacks invoked in
__do_irq():
<idle>-0 [051] dns. 132025441306354: __do_irq <-call_do_irq
<idle>-0 [051] dns. 132025441306430: irq_enter <-__do_irq
<idle>-0 [051] dns. 132025441306503: irq_enter_rcu <-__do_irq
<idle>-0 [051] dnH. 132025441306599: xive_get_irq <-__do_irq
<<>>
<idle>-0 [051] dnH. 132025441307770: generic_smp_call_function_single_interrupt <-smp_ipi_demux_relaxed
<idle>-0 [051] dnH. 132025441307839: flush_smp_call_function_queue <-smp_ipi_demux_relaxed
<idle>-0 [051] dnH. 132025441308057: _raw_spin_lock <-event_function
<idle>-0 [051] dnH. 132025441308206: power_pmu_disable <-perf_pmu_disable
<idle>-0 [051] dnH. 132025441308337: power_pmu_del <-event_sched_out
<idle>-0 [051] dnH. 132025441308407: power_pmu_read <-power_pmu_del
<idle>-0 [051] dnH. 132025441308477: read_pmc <-power_pmu_read
<idle>-0 [051] dnH. 132025441308590: isa207_disable_pmc <-power_pmu_del
<idle>-0 [051] dnH. 132025441308663: write_pmc <-power_pmu_del
<idle>-0 [051] dnH. 132025441308787: power_pmu_event_idx <-perf_event_update_userpage
<idle>-0 [051] dnH. 132025441308859: rcu_read_unlock_strict <-perf_event_update_userpage
<idle>-0 [051] dnH. 132025441308975: power_pmu_enable <-perf_pmu_enable
<<>>
<idle>-0 [051] dnH. 132025441311108: irq_exit <-__do_irq
<idle>-0 [051] dns. 132025441311319: performance_monitor_exception <-replay_soft_interrupts
Case 2: PMI's masked during local_* operations, example local_add(). If
the local_add() operation happens within a local_irq_save(), replay of
PMI will be during local_irq_restore(). Similar to case 1, this could
also create a window before replay where PMU events gets deleted or
stopped.
Fix it by updating the PMU callback function power_pmu_disable() to
check for pending perf interrupt. If there is an overflown PMC and
pending perf interrupt indicated in paca, clear the PMI bit in paca to
drop that sample. Clearing of PMI bit is done in power_pmu_disable()
since disable is invoked before any event gets deleted/stopped. With
this fix, if there are more than one event running in the PMU, there is
a chance that we clear the PMI bit for the event which is not getting
deleted/stopped. The other events may still remain active. Hence to make
sure we don't drop valid sample in such cases, another check is added in
power_pmu_enable. This checks if there is an overflown PMC found among
the active events and if so enable back the PMI bit. Two new helper
functions are introduced to clear/set the PMI, ie
clear_pmi_irq_pending() and set_pmi_irq_pending(). Helper function
pmi_irq_pending() is introduced to give a warning if there is pending
PMI bit in paca, but no PMC is overflown.
Also there are corner cases which result in performance monitor
interrupts being triggered during power_pmu_disable(). This happens
since PMXE bit is not cleared along with disabling of other MMCR0 bits
in the pmu_disable. Such PMI's could leave the PMU running and could
trigger PMI again which will set MMCR0 PMAO bit. This could lead to
spurious interrupts in some corner cases. Example, a timer after
power_pmu_del() which will re-enable interrupts and triggers a PMI again
since PMAO bit is still set. But fails to find valid overflow since PMC
was cleared in power_pmu_del(). Fix that by disabling PMXE along with
disabling of other MMCR0 bits in power_pmu_disable().
We can't just replay PMI any time. Hence this approach is preferred
rather than replaying PMI before resetting overflown PMC. Patch also
documents core-book3s on a race condition which can trigger these PMC
messages during idle path in PowerNV.
Fixes: f442d004806e ("powerpc/64s: Add support to mask perf interrupts and replay them")
Reported-by: Nageswara R Sastry <nasastry@in.ibm.com>
Suggested-by: Nicholas Piggin <npiggin@gmail.com>
Suggested-by: Madhavan Srinivasan <maddy@linux.ibm.com>
Signed-off-by: Athira Rajeev <atrajeev@linux.vnet.ibm.com>
Tested-by: Nageswara R Sastry <rnsastry@linux.ibm.com>
Reviewed-by: Nicholas Piggin <npiggin@gmail.com>
[mpe: Make pmi_irq_pending() return bool, reflow/reword some comments]
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/1626846509-1350-2-git-send-email-atrajeev@linux.vnet.ibm.com
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It can be useful in simulators (with very constrained environments)
to allow some PMCs to run from boot so they can be sampled directly
by a test harness, rather than having to run perf.
A previous change freezes counters at boot by default, so provide
a boot time option to un-freeze (plus a bit more flexibility).
Signed-off-by: Nicholas Piggin <npiggin@gmail.com>
Reviewed-by: Athira Jajeev <atrajeev@linux.vnet.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20211123095231.1036501-13-npiggin@gmail.com
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git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux
Pull powerpc updates from Michael Ellerman:
- Enable STRICT_KERNEL_RWX for Freescale 85xx platforms.
- Activate CONFIG_STRICT_KERNEL_RWX by default, while still allowing it
to be disabled.
- Add support for out-of-line static calls on 32-bit.
- Fix oopses doing bpf-to-bpf calls when STRICT_KERNEL_RWX is enabled.
- Fix boot hangs on e5500 due to stale value in ESR passed to
do_page_fault().
- Fix several bugs on pseries in handling of device tree cache
information for hotplugged CPUs, and/or during partition migration.
- Various other small features and fixes.
Thanks to Alexey Kardashevskiy, Alistair Popple, Anatolij Gustschin,
Andrew Donnellan, Athira Rajeev, Bixuan Cui, Bjorn Helgaas, Cédric Le
Goater, Christophe Leroy, Daniel Axtens, Daniel Henrique Barboza, Denis
Kirjanov, Fabiano Rosas, Frederic Barrat, Gustavo A. R. Silva, Hari
Bathini, Jacques de Laval, Joel Stanley, Kai Song, Kajol Jain, Laurent
Vivier, Leonardo Bras, Madhavan Srinivasan, Nathan Chancellor, Nathan
Lynch, Naveen N. Rao, Nicholas Piggin, Nick Desaulniers, Niklas
Schnelle, Oliver O'Halloran, Rob Herring, Russell Currey, Srikar
Dronamraju, Stan Johnson, Tyrel Datwyler, Uwe Kleine-König, Vasant
Hegde, Wan Jiabing, and Xiaoming Ni,
* tag 'powerpc-5.16-1' of git://git.kernel.org/pub/scm/linux/kernel/git/powerpc/linux: (73 commits)
powerpc/8xx: Fix Oops with STRICT_KERNEL_RWX without DEBUG_RODATA_TEST
powerpc/32e: Ignore ESR in instruction storage interrupt handler
powerpc/powernv/prd: Unregister OPAL_MSG_PRD2 notifier during module unload
powerpc: Don't provide __kernel_map_pages() without ARCH_SUPPORTS_DEBUG_PAGEALLOC
MAINTAINERS: Update powerpc KVM entry
powerpc/xmon: fix task state output
powerpc/44x/fsp2: add missing of_node_put
powerpc/dcr: Use cmplwi instead of 3-argument cmpli
KVM: PPC: Tick accounting should defer vtime accounting 'til after IRQ handling
powerpc/security: Use a mutex for interrupt exit code patching
powerpc/83xx/mpc8349emitx: Make mcu_gpiochip_remove() return void
powerpc/fsl_booke: Fix setting of exec flag when setting TLBCAMs
powerpc/book3e: Fix set_memory_x() and set_memory_nx()
powerpc/nohash: Fix __ptep_set_access_flags() and ptep_set_wrprotect()
powerpc/bpf: Fix write protecting JIT code
selftests/powerpc: Use date instead of EPOCHSECONDS in mitigation-patching.sh
powerpc/64s/interrupt: Fix check_return_regs_valid() false positive
powerpc/boot: Set LC_ALL=C in wrapper script
powerpc/64s: Default to 64K pages for 64 bit book3s
Revert "powerpc/audit: Convert powerpc to AUDIT_ARCH_COMPAT_GENERIC"
...
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git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull perf updates from Thomas Gleixner:
"Core:
- Allow ftrace to instrument parts of the perf core code
- Add a new mem_hops field to perf_mem_data_src which allows to
represent intra-node/package or inter-node/off-package details to
prepare for next generation systems which have more hieararchy
within the node/pacakge level.
Tools:
- Update for the new mem_hops field in perf_mem_data_src
Arch:
- A set of constraints fixes for the Intel uncore PMU
- The usual set of small fixes and improvements for x86 and PPC"
* tag 'perf-core-2021-10-31' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
perf/x86/intel: Fix ICL/SPR INST_RETIRED.PREC_DIST encodings
powerpc/perf: Fix data source encodings for L2.1 and L3.1 accesses
tools/perf: Add mem_hops field in perf_mem_data_src structure
perf: Add mem_hops field in perf_mem_data_src structure
perf: Add comment about current state of PERF_MEM_LVL_* namespace and remove an extra line
perf/core: Allow ftrace for functions in kernel/event/core.c
perf/x86: Add new event for AUX output counter index
perf/x86: Add compiler barrier after updating BTS
perf/x86/intel/uncore: Fix Intel SPR M3UPI event constraints
perf/x86/intel/uncore: Fix Intel SPR M2PCIE event constraints
perf/x86/intel/uncore: Fix Intel SPR IIO event constraints
perf/x86/intel/uncore: Fix Intel SPR CHA event constraints
perf/x86/intel/uncore: Fix Intel ICX IIO event constraints
perf/x86/intel/uncore: Fix invalid unit check
perf/x86/intel/uncore: Support extra IMC channel on Ice Lake server
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Fix the data source encodings to represent L2.1/L3.1(another core's
L2/L3 on the same node) accesses properly for power10 and older
plaforms.
Add new macros(LEVEL/REM) which can be used to add mem_lvl_num and remote
field data inside perf_mem_data_src structure.
Result in power9 system with patch changes:
localhost:~/linux/tools/perf # ./perf mem report | grep Remote
0.01% 1 252 Remote core, same node L3 or L3 hit [.] 0x0000000000002dd0 producer_consumer [.] 0x00007fff7f25eb90
anon HitM N/A No N/A 0 0
0.01% 1 220 Remote core, same node L3 or L3 hit [.] 0x0000000000002dd0 producer_consumer [.] 0x00007fff77776d90
anon HitM N/A No N/A 0 0
0.01% 1 220 Remote core, same node L3 or L3 hit [.] 0x0000000000002dd0 producer_consumer [.] 0x00007fff817d9410
anon HitM N/A No N/A 0 0
Fixes: 79e96f8f930d ("powerpc/perf: Export memory hierarchy info to user space")
Signed-off-by: Kajol Jain <kjain@linux.ibm.com>
Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Link: https://lore.kernel.org/r/20211006140654.298352-5-kjain@linux.ibm.com
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