On 3/31/2025 1:32 PM, H. Peter Anvin wrote:
On March 31, 2025 3:17:30 AM PDT, Ingo Molnar <mingo@xxxxxxxxxx> wrote:
* Xin Li (Intel) <xin@xxxxxxxxx> wrote:
- __wrmsr (MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3, val >> 32);
+ native_wrmsrl(MSR_AMD_DBG_EXTN_CFG, val | 3ULL << 3);
This is an improvement.
- __wrmsr (MSR_IA32_PQR_ASSOC, rmid_p, plr->closid);
+ native_wrmsrl(MSR_IA32_PQR_ASSOC, (u64)plr->closid << 32 | rmid_p);
- __wrmsr (MSR_IA32_PQR_ASSOC, rmid_p, closid_p);
+ native_wrmsrl(MSR_IA32_PQR_ASSOC, (u64)closid_p << 32 | rmid_p);
This is not an improvement.
Please provide a native_wrmsrl() API variant where natural [rmid_p, closid_p]
high/lo parameters can be used, without the shift-uglification...
Thanks,
Ingo
Directing this question primarily to Ingo, who is more than anyone else the namespace consistency guardian:
On the subject of msr function naming ... *msrl() has always been misleading. The -l suffix usually means 32 bits; sometimes it means the C type "long" (which in the kernel is used instead of size_t/uintptr_t, which might end up being "fun" when 128-bit architectures appear some time this century), but for a fixed 64-but type we normally use -q.
Should we rename the *msrl() functions to *msrq() as part of this overhaul?
Per "struct msr" defined in arch/x86/include/asm/shared/msr.h:
struct msr {
union {
struct {
u32 l;
u32 h;
};
u64 q;
};
};
Probably *msrq() is what we want?
