[PATCH v3 4/5] x86: perf: Refactor misc flag assignments

Colton Lewis
2024-09-12T20:51:40Z

Break the assignment logic for misc flags into their own respective
functions to reduce the complexity of the nested logic.

Signed-off-by: Colton Lewis <coltonlewis@google.com>
---
arch/x86/events/core.c | 31 +++++++++++++++++++++++--------
arch/x86/include/asm/perf_event.h | 2 ++
2 files changed, 25 insertions(+), 8 deletions(-)

diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c
index 760ad067527c..d51e5d24802b 100644
--- a/arch/x86/events/core.c
+++ b/arch/x86/events/core.c
@@ -2948,16 +2948,34 @@ unsigned long perf_arch_instruction_pointer(struct pt_regs *regs)
return regs->ip + code_segment_base(regs);
}

+static unsigned long common_misc_flags(struct pt_regs *regs)
+{
+ if (regs->flags & PERF_EFLAGS_EXACT)
+ return PERF_RECORD_MISC_EXACT_IP;
+
+ return 0;
+}
+
+unsigned long perf_arch_guest_misc_flags(struct pt_regs *regs)
+{
+ unsigned long guest_state = perf_guest_state();
+ unsigned long flags = common_misc_flags(regs);
+
+ if (guest_state & PERF_GUEST_USER)
+ flags |= PERF_RECORD_MISC_GUEST_USER;
+ else if (guest_state & PERF_GUEST_ACTIVE)
+ flags |= PERF_RECORD_MISC_GUEST_KERNEL;
+
+ return flags;
+}
+
unsigned long perf_arch_misc_flags(struct pt_regs *regs)
{
unsigned int guest_state = perf_guest_state();
- int misc = 0;
+ unsigned long misc = common_misc_flags(regs);

if (guest_state) {
- if (guest_state & PERF_GUEST_USER)
- misc |= PERF_RECORD_MISC_GUEST_USER;
- else
- misc |= PERF_RECORD_MISC_GUEST_KERNEL;
+ misc |= perf_arch_guest_misc_flags(regs);
} else {
if (user_mode(regs))
misc |= PERF_RECORD_MISC_USER;
@@ -2965,9 +2983,6 @@ unsigned long perf_arch_misc_flags(struct pt_regs *regs)
misc |= PERF_RECORD_MISC_KERNEL;
}

- if (regs->flags & PERF_EFLAGS_EXACT)
- misc |= PERF_RECORD_MISC_EXACT_IP;
-
return misc;
}

diff --git a/arch/x86/include/asm/perf_event.h b/arch/x86/include/asm/perf_event.h
index feb87bf3d2e9..d95f902acc52 100644
--- a/arch/x86/include/asm/perf_event.h
+++ b/arch/x86/include/asm/perf_event.h
@@ -538,7 +538,9 @@ struct x86_perf_regs {

extern unsigned long perf_arch_instruction_pointer(struct pt_regs *regs);
extern unsigned long perf_arch_misc_flags(struct pt_regs *regs);
+extern unsigned long perf_arch_guest_misc_flags(struct pt_regs *regs);
#define perf_arch_misc_flags(regs) perf_arch_misc_flags(regs)
+#define perf_arch_guest_misc_flags(regs) perf_arch_guest_misc_flags(regs)

#include <asm/stacktrace.h>

--
2.46.0.662.g92d0881bb0-goog