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| author | Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com> | 2017-05-02 19:29:34 +0300 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2017-05-15 20:30:37 +0300 |
| commit | 78a19cfdf37d19002c83c8790853c1cc10feccdc (patch) | |
| tree | 6e38f50adf729eac3552bba63eae030b0b07cb97 /scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h | |
| parent | 8df728e1ae614f592961e51f65d3e3212ede5a75 (diff) | |
| download | linux-78a19cfdf37d19002c83c8790853c1cc10feccdc.tar.xz | |
arm64: perf: Ignore exclude_hv when kernel is running in HYP
commit d98ecdaca296 ("arm64: perf: Count EL2 events if the kernel is
running in HYP") returns -EINVAL when perf system call perf_event_open is
called with exclude_hv != exclude_kernel. This change breaks applications
on VHE enabled ARMv8.1 platforms. The issue was observed with HHVM
application, which calls perf_event_open with exclude_hv = 1 and
exclude_kernel = 0.
There is no separate hypervisor privilege level when VHE is enabled, the
host kernel runs at EL2. So when VHE is enabled, we should ignore
exclude_hv from the application. This behaviour is consistent with PowerPC
where the exclude_hv is ignored when the hypervisor is not present and with
x86 where this flag is ignored.
Signed-off-by: Ganapatrao Kulkarni <ganapatrao.kulkarni@cavium.com>
[will: added comment to justify the behaviour of exclude_hv]
Signed-off-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'scripts/gcc-plugins/gcc-generate-simple_ipa-pass.h')
0 files changed, 0 insertions, 0 deletions