linux_dsm_epyc7002/arch/arm64
Julien Thierry 05ab728133 arm64: perf: Defer irq_work to IPI_IRQ_WORK
When handling events, armv8pmu_handle_irq() calls perf_event_overflow(),
and subsequently calls irq_work_run() to handle any work queued by
perf_event_overflow(). As perf_event_overflow() raises IPI_IRQ_WORK when
queuing the work, this isn't strictly necessary and the work could be
handled as part of the IPI_IRQ_WORK handler.

In the common case the IPI handler will run immediately after the PMU IRQ
handler, and where the PE is heavily loaded with interrupts other handlers
may run first, widening the window where some counters are disabled.

In practice this window is unlikely to be a significant issue, and removing
the call to irq_work_run() would make the PMU IRQ handler NMI safe in
addition to making it simpler, so let's do that.

[Alexandru E.: Reworded commit message]

Signed-off-by: Julien Thierry <julien.thierry@arm.com>
Signed-off-by: Alexandru Elisei <alexandru.elisei@arm.com>
Cc: Julien Thierry <julien.thierry.kdev@gmail.com>
Cc: Will Deacon <will.deacon@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Arnaldo Carvalho de Melo <acme@kernel.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Jiri Olsa <jolsa@redhat.com>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Link: https://lore.kernel.org/r/20200924110706.254996-5-alexandru.elisei@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-28 19:00:17 +01:00
..
boot arm64: dts: k3-am65: Update the RM resource types 2020-08-16 22:01:20 +01:00
configs ARM: SoC driver updates for v5.9 2020-08-03 19:30:59 -07:00
crypto crypto: arm64/gcm - use inline helper to suppress indirect calls 2020-07-09 22:14:32 +10:00
include arm64: perf: Add support caps under sysfs 2020-09-28 14:53:45 +01:00
kernel arm64: perf: Defer irq_work to IPI_IRQ_WORK 2020-09-28 19:00:17 +01:00
kvm - Fix kernel build with the integrated LLVM assembler which doesn't 2020-08-28 11:37:33 -07:00
lib Merge branch 'rwonce/rework' of git://git.kernel.org/pub/scm/linux/kernel/git/will/linux 2020-06-10 14:46:54 -07:00
mm treewide: Use fallthrough pseudo-keyword 2020-08-23 17:36:59 -05:00
net bpf, arm64: Add BPF exception tables 2020-07-31 00:43:40 +02:00
xen arm64: xen: Use modern annotations for assembly functions 2020-01-09 16:09:42 +00:00
Kbuild arm64: add arch/arm64/Kbuild 2019-08-21 18:47:15 +01:00
Kconfig KVM/arm64 updates for Linux 5.9: 2020-08-09 12:58:23 -04:00
Kconfig.debug arm64: remove TEXT_OFFSET randomization 2020-06-15 13:10:59 +01:00
Kconfig.platforms ARM: new SoC support for v5.9 2020-08-03 19:38:30 -07:00
Makefile arm64: vdso32: make vdso32 install conditional 2020-08-28 13:18:48 +01:00