lkml.org 
[lkml]   [2019]   [Apr]   [4]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH v7 2/4] perf/smmuv3: Add arm64 smmuv3 pmu driver
On Tue, Mar 26, 2019 at 03:17:51PM +0000, Shameer Kolothum wrote:
> From: Neil Leeder <nleeder@codeaurora.org>
>
> Adds a new driver to support the SMMUv3 PMU and add it into the
> perf events framework.
>
> Each SMMU node may have multiple PMUs associated with it, each of
> which may support different events.
>
> SMMUv3 PMCG devices are named as smmuv3_pmcg_<phys_addr_page> where
> <phys_addr_page> is the physical page address of the SMMU PMCG
> wrapped to 4K boundary. For example, the PMCG at 0xff88840000 is
> named smmuv3_pmcg_ff88840
>
> Filtering by stream id is done by specifying filtering parameters
> with the event. options are:
> filter_enable - 0 = no filtering, 1 = filtering enabled
> filter_span - 0 = exact match, 1 = pattern match
> filter_stream_id - pattern to filter against
>
> Example: perf stat -e smmuv3_pmcg_ff88840/transaction,filter_enable=1,
> filter_span=1,filter_stream_id=0x42/ -a netperf
>
> Applies filter pattern 0x42 to transaction events, which means events
> matching stream ids 0x42 & 0x43 are counted as only upper StreamID
> bits are required to match the given filter. Further filtering
> information is available in the SMMU documentation.
>
> SMMU events are not attributable to a CPU, so task mode and sampling
> are not supported.
>
> Signed-off-by: Neil Leeder <nleeder@codeaurora.org>
> Signed-off-by: Shameer Kolothum <shameerali.kolothum.thodi@huawei.com>
> Reviewed-by: Robin Murphy <robin.murphy@arm.com>
> ---
> drivers/perf/Kconfig | 9 +
> drivers/perf/Makefile | 1 +
> drivers/perf/arm_smmuv3_pmu.c | 776 ++++++++++++++++++++++++++++++++++++++++++
> 3 files changed, 786 insertions(+)
> create mode 100644 drivers/perf/arm_smmuv3_pmu.c

[...]

> +static int smmu_pmu_offline_cpu(unsigned int cpu, struct hlist_node *node)
> +{
> + struct smmu_pmu *smmu_pmu;
> + unsigned int target;
> +
> + smmu_pmu = hlist_entry_safe(node, struct smmu_pmu, node);
> + if (cpu != smmu_pmu->on_cpu)
> + return 0;
> +
> + target = cpumask_any_but(cpu_online_mask, cpu);
> + if (target >= nr_cpu_ids)
> + return 0;
> +
> + perf_pmu_migrate_context(&smmu_pmu->pmu, cpu, target);
> + smmu_pmu->on_cpu = target;
> + WARN_ON(irq_set_affinity(smmu_pmu->irq, cpumask_of(target)));

I'm going to make this (and the other invocation) use
irq_set_affinity_hint() instead, so that we can build this driver as a
module with the appropriate Kconfig tweak.

Will

\
 
 \ /
  Last update: 2019-04-04 17:31    [W:0.123 / U:0.008 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site