Changeset 53430 in vbox for trunk/include/VBox

Timestamp:

Dec 3, 2014 1:18:41 PM (10 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

97118

Message:

VMM/TM: First step in introducing the invariant TM mode.

Location:

trunk/include/VBox

Files:

• sup.h (modified) (13 diffs)
• sup.mac (modified) (1 diff)

trunk/include/VBox/sup.h

@@ -4 +4 @@
 
 /*
- * Copyright (C) 2006-2012 Oracle Corporation
+ * Copyright (C) 2006-2014 Oracle Corporation
  *
  * This file is part of VirtualBox Open Source Edition (OSE), as
@@ -339 +339 @@
      * This is index by ApicId via the aiCpuFromApicId table.
      *
-     * The clock and frequency information is updated for all CPUs if u32Mode
-     * is SUPGIPMODE_ASYNC_TSC, otherwise (SUPGIPMODE_SYNC_TSC) only the first
-     * entry is updated. */
+     * The clock and frequency information is updated for all CPUs if @c u32Mode
+     * is SUPGIPMODE_ASYNC_TSC. If @c u32Mode is SUPGIPMODE_SYNC_TSC only the first
+     * entry is updated. If @c u32Mode is SUPGIPMODE_SYNC_TSC the TSC frequency in
+     * @c u64CpuHz is copied to all CPUs. */
     SUPGIPCPU           aCPUs[1];
 } SUPGLOBALINFOPAGE;
@@ -374 +375 @@
     /** Each core has it's own TSC. */
     SUPGIPMODE_ASYNC_TSC,
+    /** The TSC of the cores are non-stop and have a constant frequency. */
+    SUPGIPMODE_INVARIANT_TSC,
     /** The usual 32-bit hack. */
     SUPGIPMODE_32BIT_HACK = 0x7fffffff
@@ -424 +427 @@
 SUPDECL(PSUPGLOBALINFOPAGE)             SUPGetGIP(void);
 
-#ifdef ___iprt_asm_amd64_x86_h
+
 /**
  * Gets the TSC frequency of the calling CPU.
@@ -435 +438 @@
     unsigned iCpu;
 
-    if (RT_UNLIKELY(!pGip || pGip->u32Magic != SUPGLOBALINFOPAGE_MAGIC))
+    if (RT_UNLIKELY(!pGip || pGip->u32Magic != SUPGLOBALINFOPAGE_MAGIC || !pGip->u64CpuHz))
         return UINT64_MAX;
 
-    if (pGip->u32Mode != SUPGIPMODE_ASYNC_TSC)
+    if (   pGip->u32Mode == SUPGIPMODE_INVARIANT_TSC
+        || pGip->u32Mode == SUPGIPMODE_SYNC_TSC)
         iCpu = 0;
     else
     {
+        Assert(pGip->u32Mode == SUPGIPMODE_ASYNC_TSC);
         iCpu = pGip->aiCpuFromApicId[ASMGetApicId()];
         if (iCpu >= pGip->cCpus)
@@ -449 +454 @@
     return pGip->aCPUs[iCpu].u64CpuHz;
 }
-#endif
+
 
 /**
@@ -1468 +1473 @@
 
 /**
- * Gets the GIP mode name given the GIP mode.
- *
- * @returns The name
- * @param   enmGipMode      The GIP mode.
+ * Gets the descriptive GIP mode name.
+ *
+ * @returns The name.
+ * @param   pGip      Pointer to the GIP.
  */
 DECLINLINE(const char *) SUPGetGIPModeName(PSUPGLOBALINFOPAGE pGip)
 {
-    Assert(pGip);
+    AssertReturn(pGip, NULL);
     switch (pGip->u32Mode)
     {
-        /* case SUPGIPMODE_INVARIANT_TSC:  return "Invariant"; */
-        case SUPGIPMODE_SYNC_TSC:       return "Synchronous";
-        case SUPGIPMODE_ASYNC_TSC:      return "Asynchronous";
-        case SUPGIPMODE_INVALID:        return "Invalid";
-        default:                        return "???";
+        case SUPGIPMODE_INVARIANT_TSC: return "Invariant";
+        case SUPGIPMODE_SYNC_TSC:      return "Synchronous";
+        case SUPGIPMODE_ASYNC_TSC:     return "Asynchronous";
+        case SUPGIPMODE_INVALID:       return "Invalid";
+        default:                       return "???";
     }
 }
@@ -1497 +1502 @@
     PSUPGLOBALINFOPAGE pGip = g_pSUPGlobalInfoPage;
     if (   pGip
-        && pGip->u32Mode == SUPGIPMODE_SYNC_TSC)   /** @todo use INVARIANT_TSC */
+        && pGip->u32Mode == SUPGIPMODE_INVARIANT_TSC)
     {
         uint64_t uLo;
@@ -1506 +1511 @@
 
         /* Arbitrary tolerance threshold, tweak later if required, perhaps
-           more tolerance on higher frequencies and less tolerance on lower. */
+           more tolerance on lower frequencies and less tolerance on higher. */
         uLo = (pGip->u64CpuHz << 10) / 1025;
         uHi = pGip->u64CpuHz + (pGip->u64CpuHz - uLo);
         if (   u64CpuHz < uLo
             || u64CpuHz > uHi)
-        {
             return false;
-        }
         return true;
     }
     return false;
 }
-
 
 
@@ -1531 +1533 @@
  *                          applied or not (optional, can be NULL).
  *
- * @remarks Maybe called with interrupts disabled!
+ * @note If you change the delta calculation made here, make sure to update the
+ *       assembly version in sup.mac! Also update supdrvGipMpEvent() while
+ *       re-adjusting deltas while choosing a new GIP master.
+ * @remarks Maybe called with interrupts disabled in ring-0!
  */
 DECLINLINE(int) SUPTscDeltaApply(PSUPGLOBALINFOPAGE pGip, uint64_t *puTsc, uint16_t idApic, bool *pfDeltaApplied)
@@ -1562 +1567 @@
 
 /**
- * Reads the delta-adjusted TSC.
+ * Gets the delta-adjusted TSC, must only be called when GIP mode is invariant
+ * (i.e. when TSC deltas are likely to be computed and available).
+ *
+ * In other GIP modes, like async, we don't bother with computing TSC deltas and
+ * therefore it is meaningless to call this function, use SUPReadTSC() instead.
  *
  * @returns VBox status code.
@@ -1572 +1581 @@
  *                          updated for other failures.
  *
- * @remarks May be called with interrupts disabled!
- */
-DECLINLINE(int) SUPReadTsc(uint64_t *puTsc, uint16_t *pidApic)
+ * @remarks May be called with interrupts disabled in ring-0!
+ */
+DECLINLINE(int) SUPGetTsc(uint64_t *puTsc, uint16_t *pidApic)
 {
 #ifdef IN_RING3
@@ -1599 +1608 @@
     return fDeltaApplied ? VINF_SUCCESS : VERR_SUPDRV_TSC_READ_FAILED;
 #endif
+}
+
+
+/**
+ * Reads the host TSC value.
+ * If applicable, normalizes the host TSC value with intercpu TSC deltas.
+ *
+ * @returns the TSC value.
+ *
+ * @remarks Requires GIP to be initialized.
+ */
+DECLINLINE(uint64_t) SUPReadTsc(void)
+{
+    if (g_pSUPGlobalInfoPage->u32Mode == SUPGIPMODE_INVARIANT_TSC)
+    {
+        uint64_t u64Tsc = UINT64_MAX;
+        int rc = SUPGetTsc(&u64Tsc, NULL /* pidApic */);
+        AssertRC(rc);
+        return u64Tsc;
+    }
+    else
+        return ASMReadTSC();
 }
 

trunk/include/VBox/sup.mac

@@ -123 +123 @@
 endstruc
 
+;;
+; Macro to apply per-CPU TSC delta to the TSC value read in through rdtsc.
+;
+; @param   %1    The pSupGipCpu pointer
+; @remarks edx:eax contains the 64-bit TSC value to apply the delta to.
+%macro SUPTscDeltaApply 1
+    ; Check if we have a valid TSC-delta, i.e. != INT64_MAX.
+    cmp     dword [%1 + SUPGIPCPU.i64TSCDelta + 4], 0xffffffff
+    jne     %%valid_delta
+    cmp     dword [%1 + SUPGIPCPU.i64TSCDelta], 0x7fffffff
+    je      %%done
+%%valid_delta:
+    ; Subtract the delta from edx:eax
+    sub     eax, dword [%1 + SUPGIPCPU.i64TSCDelta + 4]
+    sbb     edx, dword [%1 + SUPGIPCPU.i64TSCDelta]
+%%done:
+%endmacro
 
 %endif