Forcefully unbinding PMU drivers during perf sampling will lead to
a kernel panic, because the perf upper-layer framework call a NULL
pointer in this situation.
To solve this issue, "suppress_bind_attrs" should be set to true, so
that bind/unbind can be disabled via sysfs and prevent unbinding PMU
drivers during perf sampling.
Signed-off-by: Qi Liu <liuqi115@huawei.com>
Reviewed-by: John Garry <john.garry@huawei.com>
Link: https://lore.kernel.org/r/1594975763-32966-1-git-send-email-liuqi115@huawei.com
Signed-off-by: Will Deacon <will@kernel.org>
CCPI2 is a low-latency high-bandwidth serial interface for inter socket
connectivity of ThunderX2 processors.
CCPI2 PMU supports up to 8 counters per socket. Counters are
independently programmable to different events and can be started and
stopped individually. The CCPI2 counters are 64-bit and do not overflow
in normal operation.
Signed-off-by: Ganapatrao Prabhakerrao Kulkarni <gkulkarni@marvell.com>
Signed-off-by: Will Deacon <will@kernel.org>
This patch adds a perf driver for the PMU UNCORE devices DDR4 Memory
Controller(DMC) and Level 3 Cache(L3C). Each PMU supports up to 4
counters. All counters lack overflow interrupt and are
sampled periodically.
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
[will: consistent enum cpuhp_state naming]
Signed-off-by: Will Deacon <will.deacon@arm.com>
