@@ -1132,6 +1132,8 @@ static void set_seg(unsigned int which, unsigned int low, unsigned int high,
static void xen_do_write_msr(unsigned int msr, unsigned int low,
unsigned int high, int *err)
{
+ u64 val;
+
switch (msr) {
case MSR_FS_BASE:
set_seg(SEGBASE_FS, low, high, err);
@@ -1158,7 +1160,9 @@ static void xen_do_write_msr(unsigned int msr, unsigned int low,
break;
default:
- if (!pmu_msr_write(msr, low, high, err)) {
+ val = (u64)high << 32 | low;
+
+ if (!pmu_msr_write(msr, val)) {
if (err)
*err = native_write_msr_safe(msr, low, high);
else
@@ -313,37 +313,18 @@ static bool pmu_msr_chk_emulated(unsigned int msr, uint64_t *val, bool is_read,
return true;
}
-bool pmu_msr_read(unsigned int msr, uint64_t *val, int *err)
+bool pmu_msr_read(u32 msr, u64 *val)
{
bool emulated;
- if (!pmu_msr_chk_emulated(msr, val, true, &emulated))
- return false;
-
- if (!emulated) {
- *val = err ? native_read_msr_safe(msr, err)
- : native_read_msr(msr);
- }
-
- return true;
+ return pmu_msr_chk_emulated(msr, val, true, &emulated) && emulated;
}
-bool pmu_msr_write(unsigned int msr, uint32_t low, uint32_t high, int *err)
+bool pmu_msr_write(u32 msr, u64 val)
{
- uint64_t val = ((uint64_t)high << 32) | low;
bool emulated;
- if (!pmu_msr_chk_emulated(msr, &val, false, &emulated))
- return false;
-
- if (!emulated) {
- if (err)
- *err = native_write_msr_safe(msr, low, high);
- else
- native_write_msr(msr, low, high);
- }
-
- return true;
+ return pmu_msr_chk_emulated(msr, &val, false, &emulated) && emulated;
}
static u64 xen_amd_read_pmc(int counter)
@@ -271,8 +271,8 @@ void xen_pmu_finish(int cpu);
static inline void xen_pmu_init(int cpu) {}
static inline void xen_pmu_finish(int cpu) {}
#endif
-bool pmu_msr_read(unsigned int msr, uint64_t *val, int *err);
-bool pmu_msr_write(unsigned int msr, uint32_t low, uint32_t high, int *err);
+bool pmu_msr_read(u32 msr, u64 *val);
+bool pmu_msr_write(u32 msr, u64 val);
int pmu_apic_update(uint32_t reg);
u64 xen_read_pmc(int counter);
hpa found that pmu_msr_write() is actually a completely pointless function [1]: all it does is shuffle some arguments, then calls pmu_msr_chk_emulated() and if it returns true AND the emulated flag is clear then does *exactly the same thing* that the calling code would have done if pmu_msr_write() itself had returned true. And pmu_msr_read() does the equivalent stupidity. Remove the calls to native_{read,write}_msr{,_safe}() within pmu_msr_{read,write}(). Instead reuse the existing calling code that decides whether to call native_{read,write}_msr{,_safe}() based on the return value from pmu_msr_{read,write}(). Consequently, eliminate the need to pass an error pointer to pmu_msr_{read,write}(). While at it, refactor pmu_msr_write() to take the MSR value as a u64 argument, replacing the current dual u32 arguments, because the dual u32 arguments were only used to call native_write_msr{,_safe}(), which has now been removed. [1]: https://lore.kernel.org/lkml/0ec48b84-d158-47c6-b14c-3563fd14bcc4@zytor.com/ Suggested-by: H. Peter Anvin (Intel) <hpa@zytor.com> Sign-off-by: Xin Li (Intel) <xin@zytor.com> --- arch/x86/xen/enlighten_pv.c | 6 +++++- arch/x86/xen/pmu.c | 27 ++++----------------------- arch/x86/xen/xen-ops.h | 4 ++-- 3 files changed, 11 insertions(+), 26 deletions(-)