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perf/imx_ddr: Fix cpu hotplug state cleanup 

This driver allocates a dynamic cpu hotplug state but never releases it.
If reloaded in a loop it will quickly trigger a WARN message:

	"No more dynamic states available for CPU hotplug"

Fix by calling cpuhp_remove_multi_state on remove like several other
perf pmu drivers.

Also fix the cleanup logic on probe error paths: add the missing
cpuhp_remove_multi_state call and properly check the return value from
cpuhp_state_add_instant_nocalls.

Fixes: 9a66d36cc7 ("drivers/perf: imx_ddr: Add DDR performance counter support to perf")
Acked-by: Joakim Zhang <qiangqing.zhang@nxp.com>
Signed-off-by: Leonard Crestez <leonard.crestez@nxp.com>
Signed-off-by: Will Deacon <will@kernel.org>
This commit is contained in:
Leonard Crestez 2020-01-14 22:25:46 +02:00 committed by Will Deacon
parent 73daf0bba3
commit 9ee68b314e
1 changed files with 11 additions and 5 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

16
drivers/perf/fsl_imx8_ddr_perf.c
View File

@ -633,13 +633,17 @@ static int ddr_perf_probe(struct platform_device *pdev)
if (ret < 0) {
dev_err(&pdev->dev, "cpuhp_setup_state_multi failed\n");
goto ddr_perf_err;
goto cpuhp_state_err;
}
pmu->cpuhp_state = ret;
/* Register the pmu instance for cpu hotplug */
cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
ret = cpuhp_state_add_instance_nocalls(pmu->cpuhp_state, &pmu->node);
if (ret) {
dev_err(&pdev->dev, "Error %d registering hotplug\n", ret);
goto cpuhp_instance_err;
}
/* Request irq */
irq = of_irq_get(np, 0);
@ -673,9 +677,10 @@ static int ddr_perf_probe(struct platform_device *pdev)
return 0;
ddr_perf_err:
if (pmu->cpuhp_state)
cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
cpuhp_instance_err:
cpuhp_remove_multi_state(pmu->cpuhp_state);
cpuhp_state_err:
ida_simple_remove(&ddr_ida, pmu->id);
dev_warn(&pdev->dev, "i.MX8 DDR Perf PMU failed (%d), disabled\n", ret);
return ret;
@ -686,6 +691,7 @@ static int ddr_perf_remove(struct platform_device *pdev)
struct ddr_pmu *pmu = platform_get_drvdata(pdev);
cpuhp_state_remove_instance_nocalls(pmu->cpuhp_state, &pmu->node);
cpuhp_remove_multi_state(pmu->cpuhp_state);
irq_set_affinity_hint(pmu->irq, NULL);
perf_pmu_unregister(&pmu->pmu);