SBI firmware should report total number of firmware and hardware counters
including unused ones or special ones. In this case the kernel doesn't need
to make any assumptions about gaps in reported counters, e.g. excluded timer
counter. That was fixed in OpenSBI v1.1 by commit 3f66465fb6bf ("lib: pmu:
allow to use the highest available counter"). This kernel patch has no effect
if SBI firmware behaves correctly. However it eliminates access beyond the
allocated pmu_ctr_list if the kernel is used with OpenSBI older than v1.1.
Fixes: e999143459 ("RISC-V: Add perf platform driver based on SBI PMU extension")
Signed-off-by: Sergey Matyukevich <sergey.matyukevich@syntacore.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220830155306.301714-2-geomatsi@gmail.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Counter info encoding format is defined by the SBI specificaiton.
KVM implementation of SBI PMU extension will also leverage this definition.
Move the definition to common sbi header file from the sbi pmu driver.
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Link: https://lore.kernel.org/r/20220711174632.4186047-5-atishp@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Some of the SBI PMU calls does not pass 64bit arguments
correctly and not under RV32 compile time flags. Currently,
this doesn't create any incorrect results as RV64 ignores
any value in the additional register and qemu doesn't support
raw events.
Fix those SBI calls in order to set correct values for RV32.
Fixes: e999143459 ("RISC-V: Add perf platform driver based on SBI PMU extension")
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220711174632.4186047-4-atishp@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
Currently, riscv_pmu_event_set_period updates the userpage mapping.
However, the caller of riscv_pmu_event_set_period should update
the userpage mapping because the counter can not be updated/started
from set_period function in counter overflow path.
Invoke the perf_event_update_userpage at the caller so that it
doesn't get invoked twice during counter start path.
Fixes: f5bfa23f57 ("RISC-V: Add a perf core library for pmu drivers")
Reviewed-by: Anup Patel <anup@brainfault.org>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Guo Ren <guoren@kernel.org>
Cc: stable@vger.kernel.org
Link: https://lore.kernel.org/r/20220711174632.4186047-3-atishp@rivosinc.com
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
In pmu_sbi_setup_irqs(), we should call of_node_put() for the 'cpu'
when breaking out of for_each_of_cput_node() as its refcount will
be automatically increased and decreased during the iteration.
Fixes: 4905ec2fb7 ("RISC-V: Add sscofpmf extension support")
Signed-off-by: Liang He <windhl@126.com>
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Reviewed-by: Andrew Jones <ajones@ventanamicro.com>
Link: https://lore.kernel.org/r/20220715130330.443363-1-windhl@126.com
Signed-off-by: Will Deacon <will@kernel.org>
Update driver to export formatting and event information to sysfs so it
can be used by the perf user space tools with the syntaxes:
perf stat -e cpu/event=0x05
perf stat -e cpu/event=0x05,firmware=0x1/
63-bit is used to distinguish hardware events from firmware. Firmware
events are defined by "RISC-V Supervisor Binary Interface
Specification".
perf stat -e cpu/event=0x05,firmware=0x1/
is equivalent to
perf stat -e r8000000000000005
Suggested-by: João Mário Domingos <joao.mario@tecnico.ulisboa.pt>
Signed-off-by: Nikita Shubin <n.shubin@yadro.com>
Link: https://github.com/riscv-non-isa/riscv-sbi-doc/blob/master/riscv-sbi.adoc
Link: https://lore.kernel.org/r/20220628114625.166665-2-nikita.shubin@maquefel.me
Signed-off-by: Will Deacon <will@kernel.org>
Currently, when the CPU is doing suspend to ram, we don't
save pmu counter register and its content will be lost.
To ensure perf profiling is not affected by suspend to ram,
this patch is based on arm_pmu CPU_PM notifier and implements riscv
pmu pm notifier. In the pm notifier, we stop the counter and update
the counter value before suspend and start the counter after resume.
Signed-off-by: Eric Lin <eric.lin@sifive.com>
Link: https://lore.kernel.org/r/20220705091920.27432-1-eric.lin@sifive.com
Signed-off-by: Will Deacon <will@kernel.org>
This will presumably trip up some tools that try to parse the comments
as kernel doc when they're not.
Reported-by: kernel test robot <lkp@intel.com>
Fixes: 4905ec2fb7 ("RISC-V: Add sscofpmf extension support")
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
--
These recently landed in for-next, but I'm trying to avoid rewriting
history as there's a lot in flight right now.
Reviewed-by: Atish Patra <atishp@rivosinc.com>
Acked-by: Randy Dunlap <rdunlap@infradead.org>
Link: https://lore.kernel.org/r/20220322220147.11407-1-palmer@rivosinc.com
Signed-off-by: Will Deacon <will@kernel.org>
The sscofpmf extension allows counter overflow and filtering for
programmable counters. Enable the perf driver to handle the overflow
interrupt. The overflow interrupt is a hart local interrupt.
Thus, per cpu overflow interrupts are setup as a child under the root
INTC irq domain.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
RISC-V SBI specification added a PMU extension that allows to configure
start/stop any pmu counter. The RISC-V perf can use most of the generic
perf features except interrupt overflow and event filtering based on
privilege mode which will be added in future.
It also allows to monitor a handful of firmware counters that can provide
insights into firmware activity during a performance analysis.
Signed-off-by: Atish Patra <atish.patra@wdc.com>
Signed-off-by: Atish Patra <atishp@rivosinc.com>
Signed-off-by: Palmer Dabbelt <palmer@rivosinc.com>
