xnu-3247.1.106.tar.gz

[apple/xnu.git] / osfmk / i386 / fpu.c

diff --git a/osfmk/i386/fpu.c b/osfmk/i386/fpu.c
index 5f4ef89341a60a02a4ec4b7bc2bcd03a01a29056..df870f71e5aa2e524cff136905f12554b08f3d7c 100644 (file)
--- a/osfmk/i386/fpu.c
+++ b/osfmk/i386/fpu.c
@@ -241,13 +241,10 @@ init_fpu(void)
         * AVX/YMM registers
         */
        if (cpuid_features() & CPUID_FEATURE_XSAVE) {
-               cpuid_xsave_leaf_t *xsp = &cpuid_info()->cpuid_xsave_leaf;
+               cpuid_xsave_leaf_t *xsp = &cpuid_info()->cpuid_xsave_leaf[0];
                if (xsp->extended_state[0] & (uint32_t)XFEM_YMM) {
                        assert(xsp->extended_state[0] & (uint32_t) XFEM_SSE);
                        /* XSAVE container size for all features */
-                       if (xsp->extended_state[2] != sizeof(struct x86_avx_thread_state))
-                               kprintf("sizeof(struct x86_avx_thread_state)=%lu != xsp->extended_state[2]=%u\n",
-                                       sizeof(struct x86_avx_thread_state), xsp->extended_state[2]);
                        fp_register_state_size = sizeof(struct x86_avx_thread_state);
                        fpu_YMM_present = TRUE;
                        set_cr4(get_cr4() | CR4_OSXSAVE);
@@ -255,7 +252,8 @@ init_fpu(void)
                        /* Re-evaluate CPUID, once, to reflect OSXSAVE */
                        if (OSCompareAndSwap(0, 1, &cpuid_reevaluated))
                                cpuid_set_info();
-                       /* DRK: consider verifying AVX offset with cpuid(d, ECX:2) */
+                       /* Verify that now selected state can be accommodated */
+                       assert(xsp->extended_state[1] == fp_register_state_size);
                }
        }
        else
@@ -734,6 +732,8 @@ fpinit(void)
  * Coprocessor not present.
  */
 
+uint64_t x86_isr_fp_simd_use;
+
 void
 fpnoextflt(void)
 {
@@ -763,11 +763,17 @@ fpnoextflt(void)
        clear_ts();                     /*  Enable FPU use */
 
        if (__improbable(get_interrupt_level())) {
+               /* Track number of #DNA traps at interrupt context,
+                * which is likely suboptimal. Racy, but good enough.
+                */
+               x86_isr_fp_simd_use++;
                /*
-                * Save current coprocessor context if valid
-                * Initialize coprocessor live context
+                * Save current FP/SIMD context if valid
+                * Initialize live FP/SIMD registers
                 */
-               fp_save(thr_act);
+               if (pcb->ifps) {
+                       fp_save(thr_act);
+               }
                fpinit();
        } else {
                if (pcb->ifps == 0) {