Re: [PATCH v3 06/16] perf/core: Rework guest callbacks to prepare for static_call support

Boris Ostrovsky
2021-09-22T18:33:31Z

On 9/21/21 8:05 PM, Sean Christopherson wrote:
> From: Like Xu <like.xu@linux.intel.com>
>
> To prepare for using static_calls to optimize perf's guest callbacks,
> replace ->is_in_guest and ->is_user_mode with a new multiplexed hook
> ->state, tweak ->handle_intel_pt_intr to play nice with being called when
> there is no active guest, and drop "guest" from ->is_in_guest.
>
> Return '0' from ->state and ->handle_intel_pt_intr to indicate "not in
> guest" so that DEFINE_STATIC_CALL_RET0 can be used to define the static
> calls, i.e. no callback == !guest.
>
> Suggested-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Originally-by: Peter Zijlstra (Intel) <peterz@infradead.org>
> Signed-off-by: Like Xu <like.xu@linux.intel.com>
> Signed-off-by: Zhu Lingshan <lingshan.zhu@intel.com>
> [sean: extracted from static_call patch, fixed get_ip() bug, wrote changelog]
> Signed-off-by: Sean Christopherson <seanjc@google.com>

For Xen bits

Reviewed-by: Boris Ostrovsky <boris.ostrovsky@oracle.com>