svn commit: r323581 - head/sys/arm/arm

[John Baldwin]

Author: jhb
Date: Thu Sep 14 14:36:56 2017
New Revision: 323581
URL: https://svnweb.freebsd.org/changeset/base/323581

Log:
  Only mess with VFP state on the CPU for curthread for get/set_vfpcontext.
  
  Future changes will use these functions to fetch and store VFP state for
  threads other than curthread.
  
  Reviewed by:	andrew, stevek, Michal Meloun <meloun-miracle-cz>
  MFC after:	1 month
  Differential Revision:	https://reviews.freebsd.org/D12292

Modified:
  head/sys/arm/arm/machdep.c

Modified: head/sys/arm/arm/machdep.c
==============================================================================
--- head/sys/arm/arm/machdep.c	Thu Sep 14 14:30:43 2017	(r323580)
+++ head/sys/arm/arm/machdep.c	Thu Sep 14 14:36:56 2017	(r323581)
@@ -408,17 +408,18 @@ exec_setregs(struct thread *td, struct image_params *i
 static void
 get_vfpcontext(struct thread *td, mcontext_vfp_t *vfp)
 {
-	struct pcb *curpcb;
+	struct pcb *pcb;
 
-	curpcb = curthread->td_pcb;
-	critical_enter();
-
-	vfp_store(&curpcb->pcb_vfpstate, false);
-	memcpy(vfp->mcv_reg, curpcb->pcb_vfpstate.reg,
+	pcb = td->td_pcb;
+	if (td == curthread) {
+		critical_enter();
+		vfp_store(&pcb->pcb_vfpstate, false);
+		critical_exit();
+	} else
+		MPASS(TD_IS_SUSPENDED(td));
+	memcpy(vfp->mcv_reg, pcb->pcb_vfpstate.reg,
 	    sizeof(vfp->mcv_reg));
-	vfp->mcv_fpscr = curpcb->pcb_vfpstate.fpscr;
-
-	critical_exit();
+	vfp->mcv_fpscr = pcb->pcb_vfpstate.fpscr;
 }
 
 /*
@@ -427,17 +428,18 @@ get_vfpcontext(struct thread *td, mcontext_vfp_t *vfp)
 static void
 set_vfpcontext(struct thread *td, mcontext_vfp_t *vfp)
 {
-	struct pcb *curpcb;
+	struct pcb *pcb;
 
-	curpcb = curthread->td_pcb;
-	critical_enter();
-
-	vfp_discard(td);
-	memcpy(curpcb->pcb_vfpstate.reg, vfp->mcv_reg,
-	    sizeof(curpcb->pcb_vfpstate.reg));
-	curpcb->pcb_vfpstate.fpscr = vfp->mcv_fpscr;
-
-	critical_exit();
+	pcb = td->td_pcb;
+	if (td == curthread) {
+		critical_enter();
+		vfp_discard(td);
+		critical_exit();
+	} else
+		MPASS(TD_IS_SUSPENDED(td));
+	memcpy(pcb->pcb_vfpstate.reg, vfp->mcv_reg,
+	    sizeof(pcb->pcb_vfpstate.reg));
+	pcb->pcb_vfpstate.fpscr = vfp->mcv_fpscr;
 }
 #endif