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Thomas Richter 6549e9ccf3 s390/cpumf: Adjust registration of s390 PMU device drivers

[ Upstream commit 6a82e23f45fe0aa821e7a935e39d0acb20c275c0 ]

Linux-next commit titled "perf/core: Optimize perf_init_event()"
changed the semantics of PMU device driver registration.
It was done to speed up the lookup/handling of PMU device driver
specific events. It also enforces that only one PMU device
driver will be registered of type PERF_EVENT_RAW.

This change added these line in function perf_pmu_register():

  ...
  +       ret = idr_alloc(&pmu_idr, pmu, max, 0, GFP_KERNEL);
  +       if (ret < 0)
                goto free_pdc;
  +
  +       WARN_ON(type >= 0 && ret != type);

The warn_on generates a message. We have 3 PMU device drivers,
each registered as type PERF_TYPE_RAW.
The cf_diag device driver (arch/s390/kernel/perf_cpumf_cf_diag.c)
always hits the WARN_ON because it is the second PMU device driver
(after sampling device driver arch/s390/kernel/perf_cpumf_sf.c)
which is registered as type 4 (PERF_TYPE_RAW).
So when the sampling device driver is registered, ret has value 4.
When cf_diag device driver is registered with type 4,
ret has value of 5 and WARN_ON fires.

Adjust the PMU device drivers for s390 to support the new
semantics required by perf_pmu_register().

Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>

2019-12-31 16:45:43 +01:00

alpha

mm: introduce MADV_PAGEOUT

2019-09-25 17:51:41 -07:00

arc

ARC: perf: Accommodate big-endian CPU

2019-10-22 09:59:43 -07:00

arm

ARM: tegra: Fix FLOW_CTLR_HALT register clobbering by tegra_resume()

2019-12-21 11:04:48 +01:00

arm64

arm64: psci: Reduce the waiting time for cpu_psci_cpu_kill()