On Tue, Mar 04, 2025 at 07:10:13AM -0800, Dave Hansen wrote:
> So, we could have the enum be totally divorced from the hardware type:
>
> NO_STRIDE,
> PTE_STRIDE,
> PMD_STRIDE
How about we completely hide that NO_STRIDE thing and do a __invlpgb_all()
"sub-helper" which is basically telling you it is invalidating all kinds of
TLB entries and stride does not apply there:
---
diff --git a/arch/x86/include/asm/tlb.h b/arch/x86/include/asm/tlb.h
index e8561a846754..361b3dde2656 100644
--- a/arch/x86/include/asm/tlb.h
+++ b/arch/x86/include/asm/tlb.h
@@ -66,6 +66,12 @@ static inline void __invlpgb(unsigned long asid, unsigned long pcid,
asm volatile(".byte 0x0f, 0x01, 0xfe" :: "a" (rax), "c" (ecx), "d" (edx));
}
+static inline void __invlpgb_all(unsigned long asid, unsigned long pcid,
+ unsigned long addr, u16 nr_pages, u8 flags)
+{
+ __invlpgb(asid, pcid, addr, nr_pages, 0, flags);
+}
+
static inline void __tlbsync(void)
{
/*
@@ -84,6 +90,8 @@ static inline void __tlbsync(void)
static inline void __invlpgb(unsigned long asid, unsigned long pcid,
unsigned long addr, u16 nr_pages,
enum addr_stride s, u8 flags) { }
+static inline void __invlpgb_all(unsigned long asid, unsigned long pcid,
+ unsigned long addr, u16 nr_pages, u8 flags) { }
static inline void __tlbsync(void) { }
#endif
@@ -121,7 +129,7 @@ static inline void __invlpgb_flush_user_nr_nosync(unsigned long pcid,
/* Flush all mappings for a given PCID, not including globals. */
static inline void __invlpgb_flush_single_pcid_nosync(unsigned long pcid)
{
- __invlpgb(0, pcid, 0, 1, PTE_STRIDE, INVLPGB_FLAG_PCID);
+ __invlpgb_all(0, pcid, 0, 1, INVLPGB_FLAG_PCID);
}
/* Flush all mappings, including globals, for all PCIDs. */
@@ -134,7 +142,7 @@ static inline void invlpgb_flush_all(void)
* as it is cheaper.
*/
guard(preempt)();
- __invlpgb(0, 0, 0, 1, PTE_STRIDE, INVLPGB_FLAG_INCLUDE_GLOBAL);
+ __invlpgb_all(0, 0, 0, 1, INVLPGB_FLAG_INCLUDE_GLOBAL);
__tlbsync();
}
@@ -148,7 +156,7 @@ static inline void __invlpgb_flush_addr_nosync(unsigned long addr, u16 nr)
static inline void invlpgb_flush_all_nonglobals(void)
{
guard(preempt)();
- __invlpgb(0, 0, 0, 1, PTE_STRIDE, INVLPGB_MODE_ALL_NONGLOBALS);
+ __invlpgb_all(0, 0, 0, 1, INVLPGB_MODE_ALL_NONGLOBALS);
__tlbsync();
}
#endif /* _ASM_X86_TLB_H */
--
Regards/Gruss,
Boris.
https://people.kernel.org/tglx/notes-about-netiquette
