Re: [PATCH v7 4/5] x86: perf: Refactor misc flag assignments
From: Peter Zijlstra <peterz@infradead.org>
Date: 2024-11-08 15:34:37
Also in:
kvm, linux-perf-users, linux-s390, linuxppc-dev, lkml
On Thu, Nov 07, 2024 at 07:03:35PM +0000, Colton Lewis wrote:
quoted hunk ↗ jump to hunk
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 <redacted> Reviewed-by: Oliver Upton <redacted> --- arch/x86/events/core.c | 32 +++++++++++++++++++++++-------- arch/x86/include/asm/perf_event.h | 2 ++ 2 files changed, 26 insertions(+), 8 deletions(-)diff --git a/arch/x86/events/core.c b/arch/x86/events/core.c index d19e939f3998..9fdc5fa22c66 100644 --- a/arch/x86/events/core.c +++ b/arch/x86/events/core.c@@ -3011,16 +3011,35 @@ 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);
This is double common_misc and makes no sense
+ + if (!(guest_state & PERF_GUEST_ACTIVE)) + return flags; + + if (guest_state & PERF_GUEST_USER) + return flags & PERF_RECORD_MISC_GUEST_USER; + else + return flags & PERF_RECORD_MISC_GUEST_KERNEL;
And this is just broken garbage, right?
+}
Did you mean to write:
unsigned long perf_arch_guest_misc_flags(struct pt_regs *regs)
{
unsigned long guest_state = perf_guest_state();
unsigned long flags = 0;
if (guest_state & PERF_GUEST_ACTIVE) {
if (guest_state & PERF_GUEST_USER)
flags |= PERF_RECORD_MISC_GUEST_USER;
else
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);Because here you do the common thing..
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);And here you mix in the guest things.
} else {
if (user_mode(regs))
misc |= PERF_RECORD_MISC_USER;