Anshuman Khandual 4125108ec8 drivers/perf: arm_spe: Fix consistency of SYS_PMSCR_EL1.CX ... [ Upstream commit 92f2b8bafa ] The arm_spe_pmu driver will enable SYS_PMSCR_EL1.CX in order to add CONTEXT packets into the traces, if the owner of the perf event runs with required capabilities i.e CAP_PERFMON or CAP_SYS_ADMIN via perfmon_capable() helper. The value of this bit is computed in the arm_spe_event_to_pmscr() function but the check for capabilities happens in the pmu event init callback i.e arm_spe_pmu_event_init(). This suggests that the value of the CX bit should remain consistent for the duration of the perf session. However, the function arm_spe_event_to_pmscr() may be called later during the event start callback i.e arm_spe_pmu_start() when the "current" process is not the owner of the perf session, hence the CX bit setting is currently not consistent. One way to fix this, is by caching the required value of the CX bit during the initialization of the PMU event, so that it remains consistent for the duration of the session. It uses currently unused 'event->hw.flags' element to cache perfmon_capable() value, which can be referred during event start callback to compute SYS_PMSCR_EL1.CX. This ensures consistent availability of context packets in the trace as per event owner capabilities. Drop BIT(SYS_PMSCR_EL1_CX_SHIFT) check in arm_spe_pmu_event_init(), because now CX bit cannot be set in arm_spe_event_to_pmscr() with perfmon_capable() disabled. Cc: Will Deacon <will@kernel.org> Cc: Mark Rutland <mark.rutland@arm.com> Cc: Alexey Budankov <alexey.budankov@linux.intel.com> Cc: linux-arm-kernel@lists.infradead.org Cc: linux-kernel@vger.kernel.org Fixes: d5d9696b03 ("drivers/perf: Add support for ARMv8.2 Statistical Profiling Extension") Reported-by: German Gomez <german.gomez@arm.com> Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com> Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com> Link: https://lore.kernel.org/r/20220714061302.2715102-1-anshuman.khandual@arm.com Signed-off-by: Will Deacon <will@kernel.org> Signed-off-by: Sasha Levin <sashal@kernel.org>		2022-08-17 14:23:14 +02:00
..
hisilicon	perf/hisi: Constify static attribute_group structs	2021-06-08 12:49:54 +01:00
arm-cci.c	drivers/perf: arm-cci: Fix checkpatch spacing error	2021-05-25 18:59:23 +01:00
arm-ccn.c
arm-cmn.c	perf/arm-cmn: Fix CPU hotplug unregistration	2022-01-27 11:03:36 +01:00
arm_dmc620_pmu.c	perf/arm-dmc620: Use irq_set_affinity()	2021-05-24 11:01:59 +01:00
arm_dsu_pmu.c	perf/arm-dsu: Use irq_set_affinity()	2021-05-24 11:02:00 +01:00
arm_pmu.c	arm_pmu: Validate single/group leader events	2022-04-27 14:39:00 +02:00
arm_pmu_acpi.c
arm_pmu_platform.c
arm_smmuv3_pmu.c	drivers/perf: Simplify EVENT ATTR macro in SMMU PMU driver	2021-06-11 11:18:40 +01:00
arm_spe_pmu.c	drivers/perf: arm_spe: Fix consistency of SYS_PMSCR_EL1.CX	2022-08-17 14:23:14 +02:00
fsl_imx8_ddr_perf.c	perf/imx_ddr: Fix undefined behavior due to shift overflowing the constant	2022-04-20 09:34:18 +02:00
Kconfig
Makefile
qcom_l2_pmu.c	perf: qcom_l2_pmu: fix an incorrect NULL check on list iterator	2022-04-13 20:59:24 +02:00
qcom_l3_pmu.c	drivers/perf: Simplify EVENT ATTR macro in qcom_l3_pmu.c	2021-06-11 11:18:40 +01:00
thunderx2_pmu.c	drivers/perf: Remove redundant dev_err call in tx2_uncore_pmu_init_dev()	2021-05-25 18:57:19 +01:00
xgene_pmu.c	drivers/perf: Simplify EVENT ATTR macro in xgene_pmu.c	2021-06-11 11:18:40 +01:00