svn commit: r340164 - in head/sys: amd64/include arm/include arm64/include i386/include kern mips/include powerpc/include riscv/include sparc64/include

[John Baldwin]

Author: jhb
Date: Mon Nov  5 21:34:17 2018
New Revision: 340164
URL: https://svnweb.freebsd.org/changeset/base/340164

Log:
  Add a KPI for the delay while spinning on a spin lock.
  
  Replace a call to DELAY(1) with a new cpu_lock_delay() KPI.  Currently
  cpu_lock_delay() is defined to DELAY(1) on all platforms.  However,
  platforms with a DELAY() implementation that uses spin locks should
  implement a custom cpu_lock_delay() doesn't use locks.
  
  Reviewed by:	kib
  MFC after:	3 days

Modified:
  head/sys/amd64/include/cpu.h
  head/sys/arm/include/cpu.h
  head/sys/arm64/include/cpu.h
  head/sys/i386/include/cpu.h
  head/sys/kern/kern_mutex.c
  head/sys/mips/include/cpu.h
  head/sys/powerpc/include/cpu.h
  head/sys/riscv/include/cpu.h
  head/sys/sparc64/include/cpu.h

Modified: head/sys/amd64/include/cpu.h
==============================================================================
--- head/sys/amd64/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/amd64/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -50,6 +50,7 @@
 #define	cpu_getstack(td)		((td)->td_frame->tf_rsp)
 #define	cpu_setstack(td, ap)		((td)->td_frame->tf_rsp = (ap))
 #define	cpu_spinwait()			ia32_pause()
+#define	cpu_lock_delay()		DELAY(1)
 
 #define	TRAPF_USERMODE(framep) \
 	(ISPL((framep)->tf_cs) == SEL_UPL)

Modified: head/sys/arm/include/cpu.h
==============================================================================
--- head/sys/arm/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/arm/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -61,6 +61,7 @@ get_cyclecount(void)
 #define cpu_getstack(td)	((td)->td_frame->tf_usr_sp)
 #define cpu_setstack(td, sp)	((td)->td_frame->tf_usr_sp = (sp))
 #define cpu_spinwait()		/* nothing */
+#define	cpu_lock_delay()	DELAY(1)
 
 #define ARM_NVEC		8
 #define ARM_VEC_ALL		0xffffffff

Modified: head/sys/arm64/include/cpu.h
==============================================================================
--- head/sys/arm64/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/arm64/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -51,6 +51,7 @@
 #define	cpu_getstack(td)	((td)->td_frame->tf_sp)
 #define	cpu_setstack(td, sp)	((td)->td_frame->tf_sp = (sp))
 #define	cpu_spinwait()		__asm __volatile("yield" ::: "memory")
+#define	cpu_lock_delay()	DELAY(1)
 
 /* Extract CPU affinity levels 0-3 */
 #define	CPU_AFF0(mpidr)	(u_int)(((mpidr) >> 0) & 0xff)

Modified: head/sys/i386/include/cpu.h
==============================================================================
--- head/sys/i386/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/i386/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -50,6 +50,7 @@
 #define	cpu_getstack(td)		((td)->td_frame->tf_esp)
 #define	cpu_setstack(td, ap)		((td)->td_frame->tf_esp = (ap))
 #define	cpu_spinwait()			ia32_pause()
+#define	cpu_lock_delay()		DELAY(1)
 
 #define	TRAPF_USERMODE(framep) \
 	((ISPL((framep)->tf_cs) == SEL_UPL) || ((framep)->tf_eflags & PSL_VM))

Modified: head/sys/kern/kern_mutex.c
==============================================================================
--- head/sys/kern/kern_mutex.c	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/kern/kern_mutex.c	Mon Nov  5 21:34:17 2018	(r340164)
@@ -1206,7 +1206,7 @@ _mtx_lock_indefinite_check(struct mtx *m, struct lock_
 
 	ldap->spin_cnt++;
 	if (ldap->spin_cnt < 60000000 || kdb_active || panicstr != NULL)
-		DELAY(1);
+		cpu_lock_delay();
 	else {
 		td = mtx_owner(m);
 

Modified: head/sys/mips/include/cpu.h
==============================================================================
--- head/sys/mips/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/mips/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -71,6 +71,7 @@
 #define	cpu_getstack(td)	((td)->td_frame->sp)
 #define	cpu_setstack(td, nsp)	((td)->td_frame->sp = (nsp))
 #define	cpu_spinwait()		/* nothing */
+#define	cpu_lock_delay()	DELAY(1)
 
 /*
  * A machine-independent interface to the CPU's counter.

Modified: head/sys/powerpc/include/cpu.h
==============================================================================
--- head/sys/powerpc/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/powerpc/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -128,6 +128,7 @@ get_cyclecount(void)
 
 #define	cpu_getstack(td)	((td)->td_frame->fixreg[1])
 #define	cpu_spinwait()		__asm __volatile("or 27,27,27") /* yield */
+#define	cpu_lock_delay()	DELAY(1)
 
 extern char btext[];
 extern char etext[];

Modified: head/sys/riscv/include/cpu.h
==============================================================================
--- head/sys/riscv/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/riscv/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -46,6 +46,7 @@
 #define	cpu_getstack(td)	((td)->td_frame->tf_sp)
 #define	cpu_setstack(td, sp)	((td)->td_frame->tf_sp = (sp))
 #define	cpu_spinwait()		/* nothing */
+#define	cpu_lock_delay()	DELAY(1)
 
 #ifdef _KERNEL
 

Modified: head/sys/sparc64/include/cpu.h
==============================================================================
--- head/sys/sparc64/include/cpu.h	Mon Nov  5 21:32:41 2018	(r340163)
+++ head/sys/sparc64/include/cpu.h	Mon Nov  5 21:34:17 2018	(r340164)
@@ -48,6 +48,7 @@
 #define	cpu_getstack(td)	((td)->td_frame->tf_sp)
 #define	cpu_setstack(td, sp)	((td)->td_frame->tf_sp = (sp))
 #define	cpu_spinwait()		/* nothing */
+#define	cpu_lock_delay()	DELAY(1)
 
 #ifdef _KERNEL