From a4560846eba60830a444d9e336c8a18f92e099ee Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Tue, 13 May 2014 19:08:19 +0100 Subject: [PATCH] arm: perf: limit size of accounting data Commit 3fc2c83087 (ARM: perf: remove event limit from pmu_hw_events) got rid of the upper limit on the number of events an arm_pmu could handle, but introduced additional complexity and places a burden on each PMU driver to allocate accounting data somehow. So far this has not generally been useful as the only users of arm_pmu are the CPU backend and the CCI driver. Now that the CCI driver plugs into the perf subsystem directly, we can remove some of the complexities that get in the way of supporting heterogeneous CPU PMUs. This patch restores the original limits on pmu_hw_events fields such that the pmu_hw_events data can be allocated as a contiguous block. This will simplify dynamic pmu_hw_events allocation in later patches. Signed-off-by: Mark Rutland Reviewed-by: Will Deacon Reviewed-by: Stephen Boyd Tested-by: Stephen Boyd Signed-off-by: Will Deacon --- arch/arm/include/asm/pmu.h | 4 ++-- arch/arm/kernel/perf_event.c | 4 +--- arch/arm/kernel/perf_event_cpu.c | 4 ---- 3 files changed, 3 insertions(+), 9 deletions(-) diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h index ff39290965af..3d7e30bc9ffb 100644 --- a/arch/arm/include/asm/pmu.h +++ b/arch/arm/include/asm/pmu.h @@ -68,13 +68,13 @@ struct pmu_hw_events { /* * The events that are active on the PMU for the given index. */ - struct perf_event **events; + struct perf_event *events[ARMPMU_MAX_HWEVENTS]; /* * A 1 bit for an index indicates that the counter is being used for * an event. A 0 means that the counter can be used. */ - unsigned long *used_mask; + DECLARE_BITMAP(used_mask, ARMPMU_MAX_HWEVENTS); /* * Hardware lock to serialize accesses to PMU registers. Needed for the diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index 7ffb267fb628..864810713cfc 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -275,14 +275,12 @@ validate_group(struct perf_event *event) { struct perf_event *sibling, *leader = event->group_leader; struct pmu_hw_events fake_pmu; - DECLARE_BITMAP(fake_used_mask, ARMPMU_MAX_HWEVENTS); /* * Initialise the fake PMU. We only need to populate the * used_mask for the purposes of validation. */ - memset(fake_used_mask, 0, sizeof(fake_used_mask)); - fake_pmu.used_mask = fake_used_mask; + memset(&fake_pmu.used_mask, 0, sizeof(fake_pmu.used_mask)); if (!validate_event(&fake_pmu, leader)) return -EINVAL; diff --git a/arch/arm/kernel/perf_event_cpu.c b/arch/arm/kernel/perf_event_cpu.c index 7677d73cccc8..28d04642fa33 100644 --- a/arch/arm/kernel/perf_event_cpu.c +++ b/arch/arm/kernel/perf_event_cpu.c @@ -36,8 +36,6 @@ static struct arm_pmu *cpu_pmu; static DEFINE_PER_CPU(struct arm_pmu *, percpu_pmu); -static DEFINE_PER_CPU(struct perf_event * [ARMPMU_MAX_HWEVENTS], hw_events); -static DEFINE_PER_CPU(unsigned long [BITS_TO_LONGS(ARMPMU_MAX_HWEVENTS)], used_mask); static DEFINE_PER_CPU(struct pmu_hw_events, cpu_hw_events); /* @@ -172,8 +170,6 @@ static void cpu_pmu_init(struct arm_pmu *cpu_pmu) int cpu; for_each_possible_cpu(cpu) { struct pmu_hw_events *events = &per_cpu(cpu_hw_events, cpu); - events->events = per_cpu(hw_events, cpu); - events->used_mask = per_cpu(used_mask, cpu); raw_spin_lock_init(&events->pmu_lock); per_cpu(percpu_pmu, cpu) = cpu_pmu; } -- 2.34.1