diff mbox series

[v2,05/15] x86: amend cpu_has_xen_[ibt,shstk}

Message ID 8f9c3db0-bedb-4b8d-9560-3e5526288b5f@suse.com (mailing list archive)
State New, archived
Headers show
Series x86/HVM: misc tidying | expand

Commit Message

Jan Beulich Nov. 24, 2023, 8:38 a.m. UTC 
... to evaluate to false at compile-time when the respective Kconfig
control is off, thus allowing the compiler to eliminate then-dead code.

Signed-off-by: Jan Beulich <jbeulich@suse.com>
---
v2: New.

Comments

Andrew Cooper Nov. 24, 2023, 1:52 p.m. UTC | #1 
In the subject, [ -> {

?

On 24/11/2023 8:38 am, Jan Beulich wrote:
> ... to evaluate to false at compile-time when the respective Kconfig
> control is off, thus allowing the compiler to eliminate then-dead code.
>
> Signed-off-by: Jan Beulich <jbeulich@suse.com>

Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

I've got part of a series trying to do some cleanup to this effect, but
I'll rebase it around this.
Jan Beulich Nov. 27, 2023, 8:06 a.m. UTC | #2 
On 24.11.2023 14:52, Andrew Cooper wrote:
> In the subject, [ -> {
> 
> ?

Right, noticed (sadly) just after sending, and already corrected locally.

> On 24/11/2023 8:38 am, Jan Beulich wrote:
>> ... to evaluate to false at compile-time when the respective Kconfig
>> control is off, thus allowing the compiler to eliminate then-dead code.
>>
>> Signed-off-by: Jan Beulich <jbeulich@suse.com>
> 
> Acked-by: Andrew Cooper <andrew.cooper3@citrix.com>

Thanks.

Jan
diff mbox series

Patch

--- a/xen/arch/x86/include/asm/cpufeature.h
+++ b/xen/arch/x86/include/asm/cpufeature.h
@@ -215,8 +215,10 @@  static inline bool boot_cpu_has(unsigned
 #define cpu_has_lfence_dispatch boot_cpu_has(X86_FEATURE_LFENCE_DISPATCH)
 #define cpu_has_nscb            boot_cpu_has(X86_FEATURE_NSCB)
 #define cpu_has_xen_lbr         boot_cpu_has(X86_FEATURE_XEN_LBR)
-#define cpu_has_xen_shstk       boot_cpu_has(X86_FEATURE_XEN_SHSTK)
-#define cpu_has_xen_ibt         boot_cpu_has(X86_FEATURE_XEN_IBT)
+#define cpu_has_xen_shstk       (IS_ENABLED(CONFIG_XEN_SHSTK) && \
+                                 boot_cpu_has(X86_FEATURE_XEN_SHSTK))
+#define cpu_has_xen_ibt         (IS_ENABLED(CONFIG_XEN_IBT) && \
+                                 boot_cpu_has(X86_FEATURE_XEN_IBT))
 
 #define cpu_has_msr_tsc_aux     (cpu_has_rdtscp || cpu_has_rdpid)