[PATCH 06/19] ARM: l2x0: Fix group validation
From: Robin Murphy <robin.murphy@arm.com>
Date: 2025-08-13 17:01:52
Also in:
amd-gfx, dmaengine, dri-devel, imx, intel-gfx, intel-xe, linux-alpha, linux-amlogic, linux-arm-kernel, linux-arm-msm, linux-cxl, linux-fpga, linux-iommu, linux-mips, linux-perf-users, linux-pm, linux-riscv, linux-rockchip, linux-s390, linux-sh, lkml, loongarch, sparclinux
Subsystem:
arm port, the rest · Maintainers:
Russell King, Linus Torvalds
The group validation here is almost right, but fails to count the new event itself. While we fix that, also adopt the standard pattern to avoid racy access the sibling list and drop checks that are redundant with core code. Signed-off-by: Robin Murphy <robin.murphy@arm.com> --- arch/arm/mm/cache-l2x0-pmu.c | 9 ++++----- 1 file changed, 4 insertions(+), 5 deletions(-)
diff --git a/arch/arm/mm/cache-l2x0-pmu.c b/arch/arm/mm/cache-l2x0-pmu.c
index 93ef0502b7ff..6fc1171031a8 100644
--- a/arch/arm/mm/cache-l2x0-pmu.c
+++ b/arch/arm/mm/cache-l2x0-pmu.c@@ -274,18 +274,17 @@ static bool l2x0_pmu_group_is_valid(struct perf_event *event) struct pmu *pmu = event->pmu; struct perf_event *leader = event->group_leader; struct perf_event *sibling; - int num_hw = 0; + int num_hw = 1; + + if (leader == event) + return true; if (leader->pmu == pmu) num_hw++; - else if (!is_software_event(leader)) - return false; for_each_sibling_event(sibling, leader) { if (sibling->pmu == pmu) num_hw++; - else if (!is_software_event(sibling)) - return false; } return num_hw <= PMU_NR_COUNTERS;
--
2.39.2.101.g768bb238c484.dirty