LLVM ignores everything inside the if statement and doesn't generate
errors, but GCC doesn't ignore it, resulting in the following error:
drivers/perf/arm_pmuv3.c: In function ‘armv8pmu_write_evtype’:
include/linux/bits.h:34:29: error: left shift count >= width of type [-Werror=shift-count-overflow]
34 | (((~UL(0)) - (UL(1) << (l)) + 1) & \
Fix it by using GENMASK_ULL which doesn't overflow on arm32 (even though
the value is never used there).
Fixes: 3115ee021bfb ("arm64: perf: Include threshold control fields in PMEVTYPER mask")
Reported-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Closes: https://lore.kernel.org/linux-arm-kernel/20231215120817.h2f3akgv72zhrtqo@pengutronix.de/
Signed-off-by: James Clark <james.clark@arm.com>
Acked-by: Mark Rutland <mark.rutland@arm.com>
Reviewed-by: Uwe Kleine-König <u.kleine-koenig@pengutronix.de>
Link: https://lore.kernel.org/r/20231215175648.3397170-2-james.clark@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
FEAT_PMUv3_TH (Armv8.8) permits a PMU counter to increment only on events whose count meets a specified threshold condition. For example if PMEVTYPERn.TC (Threshold Control) is set to 0b101 (Greater than or equal, count), and the threshold is set to 2, then the PMU counter will now only increment by 1 when an event would have previously incremented the PMU counter by 2 or more on a single processor cycle. Three new Perf event config fields, 'threshold', 'threshold_compare' and 'threshold_count' have been added to control the feature. threshold_compare maps to the upper two bits of PMEVTYPERn.TC and threshold_count maps to the first bit of TC. These separate attributes have been picked rather than enumerating all the possible combinations of the TC field as in the Arm ARM. The attributes would be used on a Perf command line like this: $ perf stat -e stall_slot/threshold=2,threshold_compare=2/ A new capability for reading out the maximum supported threshold value has also been added: $ cat /sys/bus/event_source/devices/armv8_pmuv3/caps/threshold_max 0x000000ff If a threshold higher than threshold_max is provided, then an error is generated. If FEAT_PMUv3_TH isn't implemented or a 32 bit kernel is running, then threshold_max reads zero, and attempting to set a threshold value will also result in an error. The threshold is per PMU counter, and there are potentially different threshold_max values per PMU type on heterogeneous systems. Bits higher than 32 now need to be written into PMEVTYPER, so armv8pmu_write_evtype() has to be updated to take an unsigned long value rather than u32 which gives the correct behavior on both aarch32 and 64. Signed-off-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/20231211161331.1277825-11-james.clark@arm.com Signed-off-by: Will Deacon <will@kernel.org>
This mechanism makes it much easier to define and read new attributes so move it to the arm_pmu.h header so that it can be shared. At the same time update the existing format attributes to use it. GENMASK has to be changed to GENMASK_ULL because the config fields are 64 bits even on arm32 where this will also be used now. Signed-off-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/20231211161331.1277825-7-james.clark@arm.com Signed-off-by: Will Deacon <will@kernel.org>
FEAT_PMUv3_TH (Armv8.8) adds two new fields to PMEVTYPER, so include them in the mask. These aren't writable on 32 bit kernels as they are in the high part of the register, so only include them for arm64. It would be difficult to do this statically in the asm header files for each platform without resulting in circular includes or #ifdefs inline in the code. For that reason the ARMV8_PMU_EVTYPE_MASK definition has been removed and the mask is constructed programmatically. Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Anshuman Khandual <anshuman.khandual@arm.com> Signed-off-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/20231211161331.1277825-6-james.clark@arm.com Signed-off-by: Will Deacon <will@kernel.org>
Convert the remaining fields to use either GENMASK or be built from other fields. These all already started at bit 0 so don't need a code change for the lack of _SHIFT. Signed-off-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/20231211161331.1277825-5-james.clark@arm.com Signed-off-by: Will Deacon <will@kernel.org>
This is so that FIELD_GET and FIELD_PREP can be used and that the fields are in a consistent format to arm64/tools/sysreg Signed-off-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/20231211161331.1277825-4-james.clark@arm.com Signed-off-by: Will Deacon <will@kernel.org>
This is so that FIELD_GET and FIELD_PREP can be used and that the fields are in a consistent format to arm64/tools/sysreg Signed-off-by: James Clark <james.clark@arm.com> Link: https://lore.kernel.org/r/20231211161331.1277825-3-james.clark@arm.com Signed-off-by: Will Deacon <will@kernel.org>
As 'pmu_lock' element is not being used in any ARM PMU implementation, just drop this from 'struct pmu_hw_events'. Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Acked-by: Mark Rutland <mark.rutland@arm.com> Link: https://lore.kernel.org/r/20231115092805.737822-3-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org>
Suzuki noticed that KVM's PMU emulation is oblivious to the NSU and NSK event filter bits. On systems that have EL3 these bits modify the filter behavior in non-secure EL0 and EL1, respectively. Even though the kernel doesn't use these bits, it is entirely possible some other guest OS does. Additionally, it would appear that these and the M bit are required by the architecture if EL3 is implemented. Allow the EL3 event filter bits to be set if EL3 is advertised in the guest's ID register. Implement the behavior of NSU and NSK according to the pseudocode, and entirely ignore the M bit for perf event creation. Reported-by: Suzuki K Poulose <suzuki.poulose@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20231019185618.3442949-3-oliver.upton@linux.dev Signed-off-by: Oliver Upton <oliver.upton@linux.dev>
Pull RISC-V updates from Palmer Dabbelt: - Support for the new "riscv,isa-extensions" and "riscv,isa-base" device tree interfaces for probing extensions - Support for userspace access to the performance counters - Support for more instructions in kprobes - Crash kernels can be allocated above 4GiB - Support for KCFI - Support for ELFs in !MMU configurations - ARCH_KMALLOC_MINALIGN has been reduced to 8 - mmap() defaults to sv48-sized addresses, with longer addresses hidden behind a hint (similar to Arm and Intel) - Also various fixes and cleanups * tag 'riscv-for-linus-6.6-mw1' of git://git.kernel.org/pub/scm/linux/kernel/git/riscv/linux: (51 commits) lib/Kconfig.debug: Restrict DEBUG_INFO_SPLIT for RISC-V riscv: support PREEMPT_DYNAMIC with static keys riscv: Move create_tmp_mapping() to init sections riscv: Mark KASAN tmp* page tables variables as static riscv: mm: use bitmap_zero() API riscv: enable DEBUG_FORCE_FUNCTION_ALIGN_64B riscv: remove redundant mv instructions RISC-V: mm: Document mmap changes RISC-V: mm: Update pgtable comment documentation RISC-V: mm: Add tests for RISC-V mm RISC-V: mm: Restrict address space for sv39,sv48,sv57 riscv: enable DMA_BOUNCE_UNALIGNED_KMALLOC for !dma_coherent riscv: allow kmalloc() caches aligned to the smallest value riscv: support the elf-fdpic binfmt loader binfmt_elf_fdpic: support 64-bit systems riscv: Allow CONFIG_CFI_CLANG to be selected riscv/purgatory: Disable CFI riscv: Add CFI error handling riscv: Add ftrace_stub_graph riscv: Add types to indirectly called assembly functions ...