svn commit: r221283 - in projects/largeSMP/sys/i386: i386 include xen

Attilio Rao attilio at FreeBSD.org
Sat Apr 30 23:02:18 UTC 2011


Author: attilio
Date: Sat Apr 30 23:02:17 2011
New Revision: 221283
URL: http://svn.freebsd.org/changeset/base/221283

Log:
  Remove the support for lazy cr3 switching from i386.
  amd64 has already this micro-optimization removed.
  
  Submitted by:	kib

Modified:
  projects/largeSMP/sys/i386/i386/apic_vector.s
  projects/largeSMP/sys/i386/i386/db_trace.c
  projects/largeSMP/sys/i386/i386/mp_machdep.c
  projects/largeSMP/sys/i386/i386/pmap.c
  projects/largeSMP/sys/i386/i386/swtch.s
  projects/largeSMP/sys/i386/include/smp.h
  projects/largeSMP/sys/i386/xen/pmap.c

Modified: projects/largeSMP/sys/i386/i386/apic_vector.s
==============================================================================
--- projects/largeSMP/sys/i386/i386/apic_vector.s	Sat Apr 30 23:00:41 2011	(r221282)
+++ projects/largeSMP/sys/i386/i386/apic_vector.s	Sat Apr 30 23:02:17 2011	(r221283)
@@ -357,20 +357,4 @@ IDTVEC(rendezvous)
 	POP_FRAME
 	iret
 	
-/*
- * Clean up when we lose out on the lazy context switch optimization.
- * ie: when we are about to release a PTD but a cpu is still borrowing it.
- */
-	SUPERALIGN_TEXT
-IDTVEC(lazypmap)
-	PUSH_FRAME
-	SET_KERNEL_SREGS
-	cld
-
-	call	pmap_lazyfix_action
-
-	movl	lapic, %eax
-	movl	$0, LA_EOI(%eax)	/* End Of Interrupt to APIC */
-	POP_FRAME
-	iret
 #endif /* SMP */

Modified: projects/largeSMP/sys/i386/i386/db_trace.c
==============================================================================
--- projects/largeSMP/sys/i386/i386/db_trace.c	Sat Apr 30 23:00:41 2011	(r221282)
+++ projects/largeSMP/sys/i386/i386/db_trace.c	Sat Apr 30 23:02:17 2011	(r221283)
@@ -312,8 +312,7 @@ db_nextframe(struct i386_frame **fp, db_
 			frame_type = TRAP_TIMERINT;
 		else if (strcmp(name, "Xcpustop") == 0 ||
 		    strcmp(name, "Xrendezvous") == 0 ||
-		    strcmp(name, "Xipi_intr_bitmap_handler") == 0 ||
-		    strcmp(name, "Xlazypmap") == 0)
+		    strcmp(name, "Xipi_intr_bitmap_handler") == 0)
 			frame_type = TRAP_INTERRUPT;
 	}
 

Modified: projects/largeSMP/sys/i386/i386/mp_machdep.c
==============================================================================
--- projects/largeSMP/sys/i386/i386/mp_machdep.c	Sat Apr 30 23:00:41 2011	(r221282)
+++ projects/largeSMP/sys/i386/i386/mp_machdep.c	Sat Apr 30 23:02:17 2011	(r221283)
@@ -165,7 +165,6 @@ u_long *ipi_invlrng_counts[MAXCPU];
 u_long *ipi_invlpg_counts[MAXCPU];
 u_long *ipi_invlcache_counts[MAXCPU];
 u_long *ipi_rendezvous_counts[MAXCPU];
-u_long *ipi_lazypmap_counts[MAXCPU];
 static u_long *ipi_hardclock_counts[MAXCPU];
 #endif
 
@@ -552,10 +551,6 @@ cpu_mp_start(void)
 	setidt(IPI_INVLCACHE, IDTVEC(invlcache),
 	       SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
 
-	/* Install an inter-CPU IPI for lazy pmap release */
-	setidt(IPI_LAZYPMAP, IDTVEC(lazypmap),
-	       SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
-
 	/* Install an inter-CPU IPI for all-CPU rendezvous */
 	setidt(IPI_RENDEZVOUS, IDTVEC(rendezvous),
 	       SDT_SYS386IGT, SEL_KPL, GSEL(GCODE_SEL, SEL_KPL));
@@ -1682,8 +1677,6 @@ mp_ipi_intrcnt(void *dummy)
 		intrcnt_add(buf, &ipi_ast_counts[i]);
 		snprintf(buf, sizeof(buf), "cpu%d:rendezvous", i);
 		intrcnt_add(buf, &ipi_rendezvous_counts[i]);
-		snprintf(buf, sizeof(buf), "cpu%d:lazypmap", i);
-		intrcnt_add(buf, &ipi_lazypmap_counts[i]);
 		snprintf(buf, sizeof(buf), "cpu%d:hardclock", i);
 		intrcnt_add(buf, &ipi_hardclock_counts[i]);
 	}		

Modified: projects/largeSMP/sys/i386/i386/pmap.c
==============================================================================
--- projects/largeSMP/sys/i386/i386/pmap.c	Sat Apr 30 23:00:41 2011	(r221282)
+++ projects/largeSMP/sys/i386/i386/pmap.c	Sat Apr 30 23:02:17 2011	(r221283)
@@ -1881,98 +1881,6 @@ retry:
 * Pmap allocation/deallocation routines.
  ***************************************************/
 
-#ifdef SMP
-/*
- * Deal with a SMP shootdown of other users of the pmap that we are
- * trying to dispose of.  This can be a bit hairy.
- */
-static cpumask_t *lazymask;
-static u_int lazyptd;
-static volatile u_int lazywait;
-
-void pmap_lazyfix_action(void);
-
-void
-pmap_lazyfix_action(void)
-{
-	cpumask_t mymask = PCPU_GET(cpumask);
-
-#ifdef COUNT_IPIS
-	(*ipi_lazypmap_counts[PCPU_GET(cpuid)])++;
-#endif
-	if (rcr3() == lazyptd)
-		load_cr3(PCPU_GET(curpcb)->pcb_cr3);
-	atomic_clear_int(lazymask, mymask);
-	atomic_store_rel_int(&lazywait, 1);
-}
-
-static void
-pmap_lazyfix_self(cpumask_t mymask)
-{
-
-	if (rcr3() == lazyptd)
-		load_cr3(PCPU_GET(curpcb)->pcb_cr3);
-	atomic_clear_int(lazymask, mymask);
-}
-
-
-static void
-pmap_lazyfix(pmap_t pmap)
-{
-	cpumask_t mymask, mask;
-	u_int spins;
-
-	while ((mask = pmap->pm_active) != 0) {
-		spins = 50000000;
-		mask = mask & -mask;	/* Find least significant set bit */
-		mtx_lock_spin(&smp_ipi_mtx);
-#ifdef PAE
-		lazyptd = vtophys(pmap->pm_pdpt);
-#else
-		lazyptd = vtophys(pmap->pm_pdir);
-#endif
-		mymask = PCPU_GET(cpumask);
-		if (mask == mymask) {
-			lazymask = &pmap->pm_active;
-			pmap_lazyfix_self(mymask);
-		} else {
-			atomic_store_rel_int((u_int *)&lazymask,
-			    (u_int)&pmap->pm_active);
-			atomic_store_rel_int(&lazywait, 0);
-			ipi_selected(mask, IPI_LAZYPMAP);
-			while (lazywait == 0) {
-				ia32_pause();
-				if (--spins == 0)
-					break;
-			}
-		}
-		mtx_unlock_spin(&smp_ipi_mtx);
-		if (spins == 0)
-			printf("pmap_lazyfix: spun for 50000000\n");
-	}
-}
-
-#else	/* SMP */
-
-/*
- * Cleaning up on uniprocessor is easy.  For various reasons, we're
- * unlikely to have to even execute this code, including the fact
- * that the cleanup is deferred until the parent does a wait(2), which
- * means that another userland process has run.
- */
-static void
-pmap_lazyfix(pmap_t pmap)
-{
-	u_int cr3;
-
-	cr3 = vtophys(pmap->pm_pdir);
-	if (cr3 == rcr3()) {
-		load_cr3(PCPU_GET(curpcb)->pcb_cr3);
-		pmap->pm_active &= ~(PCPU_GET(cpumask));
-	}
-}
-#endif	/* SMP */
-
 /*
  * Release any resources held by the given physical map.
  * Called when a pmap initialized by pmap_pinit is being released.
@@ -1990,7 +1898,6 @@ pmap_release(pmap_t pmap)
 	KASSERT(pmap->pm_root == NULL,
 	    ("pmap_release: pmap has reserved page table page(s)"));
 
-	pmap_lazyfix(pmap);
 	mtx_lock_spin(&allpmaps_lock);
 	LIST_REMOVE(pmap, pm_list);
 	mtx_unlock_spin(&allpmaps_lock);

Modified: projects/largeSMP/sys/i386/i386/swtch.s
==============================================================================
--- projects/largeSMP/sys/i386/i386/swtch.s	Sat Apr 30 23:00:41 2011	(r221282)
+++ projects/largeSMP/sys/i386/i386/swtch.s	Sat Apr 30 23:02:17 2011	(r221283)
@@ -174,12 +174,6 @@ ENTRY(cpu_switch)
 
 	/* switch address space */
 	movl	PCB_CR3(%edx),%eax
-#ifdef PAE
-	cmpl	%eax,IdlePDPT			/* Kernel address space? */
-#else
-	cmpl	%eax,IdlePTD			/* Kernel address space? */
-#endif
-	je	sw0
 	READ_CR3(%ebx)				/* The same address space? */
 	cmpl	%ebx,%eax
 	je	sw0

Modified: projects/largeSMP/sys/i386/include/smp.h
==============================================================================
--- projects/largeSMP/sys/i386/include/smp.h	Sat Apr 30 23:00:41 2011	(r221282)
+++ projects/largeSMP/sys/i386/include/smp.h	Sat Apr 30 23:02:17 2011	(r221283)
@@ -42,7 +42,6 @@ extern u_long *ipi_invlrng_counts[MAXCPU
 extern u_long *ipi_invlpg_counts[MAXCPU];
 extern u_long *ipi_invlcache_counts[MAXCPU];
 extern u_long *ipi_rendezvous_counts[MAXCPU];
-extern u_long *ipi_lazypmap_counts[MAXCPU];
 #endif
 
 /* IPI handlers */
@@ -53,8 +52,7 @@ inthand_t
 	IDTVEC(invlcache),	/* Write back and invalidate cache */
 	IDTVEC(ipi_intr_bitmap_handler), /* Bitmap based IPIs */ 
 	IDTVEC(cpustop),	/* CPU stops & waits to be restarted */
-	IDTVEC(rendezvous),	/* handle CPU rendezvous */
-	IDTVEC(lazypmap);	/* handle lazy pmap release */
+	IDTVEC(rendezvous);	/* handle CPU rendezvous */
 
 /* functions in mp_machdep.c */
 void	cpu_add(u_int apic_id, char boot_cpu);

Modified: projects/largeSMP/sys/i386/xen/pmap.c
==============================================================================
--- projects/largeSMP/sys/i386/xen/pmap.c	Sat Apr 30 23:00:41 2011	(r221282)
+++ projects/largeSMP/sys/i386/xen/pmap.c	Sat Apr 30 23:02:17 2011	(r221283)
@@ -1681,98 +1681,6 @@ retry:
 * Pmap allocation/deallocation routines.
  ***************************************************/
 
-#ifdef SMP
-/*
- * Deal with a SMP shootdown of other users of the pmap that we are
- * trying to dispose of.  This can be a bit hairy.
- */
-static cpumask_t *lazymask;
-static u_int lazyptd;
-static volatile u_int lazywait;
-
-void pmap_lazyfix_action(void);
-
-void
-pmap_lazyfix_action(void)
-{
-	cpumask_t mymask = PCPU_GET(cpumask);
-
-#ifdef COUNT_IPIS
-	(*ipi_lazypmap_counts[PCPU_GET(cpuid)])++;
-#endif
-	if (rcr3() == lazyptd)
-		load_cr3(PCPU_GET(curpcb)->pcb_cr3);
-	atomic_clear_int(lazymask, mymask);
-	atomic_store_rel_int(&lazywait, 1);
-}
-
-static void
-pmap_lazyfix_self(cpumask_t mymask)
-{
-
-	if (rcr3() == lazyptd)
-		load_cr3(PCPU_GET(curpcb)->pcb_cr3);
-	atomic_clear_int(lazymask, mymask);
-}
-
-
-static void
-pmap_lazyfix(pmap_t pmap)
-{
-	cpumask_t mymask, mask;
-	u_int spins;
-
-	while ((mask = pmap->pm_active) != 0) {
-		spins = 50000000;
-		mask = mask & -mask;	/* Find least significant set bit */
-		mtx_lock_spin(&smp_ipi_mtx);
-#ifdef PAE
-		lazyptd = vtophys(pmap->pm_pdpt);
-#else
-		lazyptd = vtophys(pmap->pm_pdir);
-#endif
-		mymask = PCPU_GET(cpumask);
-		if (mask == mymask) {
-			lazymask = &pmap->pm_active;
-			pmap_lazyfix_self(mymask);
-		} else {
-			atomic_store_rel_int((u_int *)&lazymask,
-			    (u_int)&pmap->pm_active);
-			atomic_store_rel_int(&lazywait, 0);
-			ipi_selected(mask, IPI_LAZYPMAP);
-			while (lazywait == 0) {
-				ia32_pause();
-				if (--spins == 0)
-					break;
-			}
-		}
-		mtx_unlock_spin(&smp_ipi_mtx);
-		if (spins == 0)
-			printf("pmap_lazyfix: spun for 50000000\n");
-	}
-}
-
-#else	/* SMP */
-
-/*
- * Cleaning up on uniprocessor is easy.  For various reasons, we're
- * unlikely to have to even execute this code, including the fact
- * that the cleanup is deferred until the parent does a wait(2), which
- * means that another userland process has run.
- */
-static void
-pmap_lazyfix(pmap_t pmap)
-{
-	u_int cr3;
-
-	cr3 = vtophys(pmap->pm_pdir);
-	if (cr3 == rcr3()) {
-		load_cr3(PCPU_GET(curpcb)->pcb_cr3);
-		pmap->pm_active &= ~(PCPU_GET(cpumask));
-	}
-}
-#endif	/* SMP */
-
 /*
  * Release any resources held by the given physical map.
  * Called when a pmap initialized by pmap_pinit is being released.


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