svn commit: r338712 - head/sys/amd64/amd64

[Konstantin Belousov]

Author: kib
Date: Mon Sep 17 15:34:19 2018
New Revision: 338712
URL: https://svnweb.freebsd.org/changeset/base/338712

Log:
  Calculate PTI, PCID and INVPCID modes earlier, before ifuncs are resolved.
  
  This will be used in following conversion of pmap_activate_sw().
  
  Reviewed by:	alc, markj
  Sponsored by:	The FreeBSD Foundation
  Approved by:	re (gjb)
  Differential revision:	https://reviews.freebsd.org/D17181

Modified:
  head/sys/amd64/amd64/machdep.c
  head/sys/amd64/amd64/pmap.c

Modified: head/sys/amd64/amd64/machdep.c
==============================================================================
--- head/sys/amd64/amd64/machdep.c	Mon Sep 17 14:59:05 2018	(r338711)
+++ head/sys/amd64/amd64/machdep.c	Mon Sep 17 15:34:19 2018	(r338712)
@@ -1581,6 +1581,21 @@ hammer_time(u_int64_t modulep, u_int64_t physfree)
 	 */
 	identify_cpu2();
 
+	/*
+	 * Check for pti, pcid, and invpcid before ifuncs are
+	 * resolved, to correctly select the implementation for
+	 * pmap_activate_sw_mode().
+	 */
+	pti = pti_get_default();
+	TUNABLE_INT_FETCH("vm.pmap.pti", &pti);
+	TUNABLE_INT_FETCH("vm.pmap.pcid_enabled", &pmap_pcid_enabled);
+	if ((cpu_feature2 & CPUID2_PCID) != 0 && pmap_pcid_enabled) {
+		invpcid_works = (cpu_stdext_feature &
+		    CPUID_STDEXT_INVPCID) != 0;
+	} else {
+		pmap_pcid_enabled = 0;
+	}
+
 	link_elf_ireloc(kmdp);
 
 	/*
@@ -1645,9 +1660,6 @@ hammer_time(u_int64_t modulep, u_int64_t physfree)
 	mtx_init(&dt_lock, "descriptor tables", NULL, MTX_DEF);
 
 	/* exceptions */
-	pti = pti_get_default();
-	TUNABLE_INT_FETCH("vm.pmap.pti", &pti);
-
 	for (x = 0; x < NIDT; x++)
 		setidt(x, pti ? &IDTVEC(rsvd_pti) : &IDTVEC(rsvd), SDT_SYSIGT,
 		    SEL_KPL, 0);

Modified: head/sys/amd64/amd64/pmap.c
==============================================================================
--- head/sys/amd64/amd64/pmap.c	Mon Sep 17 14:59:05 2018	(r338711)
+++ head/sys/amd64/amd64/pmap.c	Mon Sep 17 15:34:19 2018	(r338712)
@@ -1179,11 +1179,7 @@ pmap_bootstrap(vm_paddr_t *firstaddr)
 	pmap_init_pat();
 
 	/* Initialize TLB Context Id. */
-	TUNABLE_INT_FETCH("vm.pmap.pcid_enabled", &pmap_pcid_enabled);
-	if ((cpu_feature2 & CPUID2_PCID) != 0 && pmap_pcid_enabled) {
-		/* Check for INVPCID support */
-		invpcid_works = (cpu_stdext_feature & CPUID_STDEXT_INVPCID)
-		    != 0;
+	if (pmap_pcid_enabled) {
 		for (i = 0; i < MAXCPU; i++) {
 			kernel_pmap->pm_pcids[i].pm_pcid = PMAP_PCID_KERN;
 			kernel_pmap->pm_pcids[i].pm_gen = 1;
@@ -1204,8 +1200,6 @@ pmap_bootstrap(vm_paddr_t *firstaddr)
 		 * during pcpu setup.
 		 */
 		load_cr4(rcr4() | CR4_PCIDE);
-	} else {
-		pmap_pcid_enabled = 0;
 	}
 }