Rethink the MD interfaces for libpthread to account for

archs that can (or are required to) have per-thread registers.

Tested on i386, amd64; marcel is testing on ia64 and will
have some follow-up commits.

Reviewed by:	davidxu

1 files changed, 207 insertions, 34 deletions

diff --git a/lib/libpthread/arch/amd64/include/pthread_md.h b/lib/libpthread/arch/amd64/include/pthread_md.h
index 3c7cd03..27a07cc 100644
--- a/lib/libpthread/arch/amd64/include/pthread_md.h
+++ b/lib/libpthread/arch/amd64/include/pthread_md.h
@@ -1,27 +1,28 @@
-/*
- * Copyright (c) 2003 Marcel Moolenaar
+/*-
+ * Copyright (C) 2003 David Xu <davidxu@freebsd.org>
+ * Copyright (c) 2001 Daniel Eischen <deischen@freebsd.org>
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
- *
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
- * 2. Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in the
- *    documentation and/or other materials provided with the distribution.
+ * 2. Neither the name of the author nor the names of its contributors
+ *    may be used to endorse or promote products derived from this software
+ *    without specific prior written permission.
  *
- * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
- * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
- * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
- * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
- * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
- * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
- * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
- * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
  *
  * $FreeBSD$
  */
@@ -31,52 +32,224 @@
 #ifndef _PTHREAD_MD_H_
 #define	_PTHREAD_MD_H_
 
+#include <sys/types.h>
+#include <sys/kse.h>
+#include <machine/sysarch.h>
 #include <ucontext.h>
 
+/* <machine/sysarch.h> should define this, but doesn't. */
+extern int sysarch(int, void *);
+
 #define	THR_GETCONTEXT(ucp)	\
 	(void)_amd64_save_context(&(ucp)->uc_mcontext)
 #define	THR_SETCONTEXT(ucp)	\
-	(void)_amd64_restore_context(&(ucp)->uc_mcontext, NULL, NULL)
+	(void)_amd64_restore_context(&(ucp)->uc_mcontext, 0, NULL)
+
 
-#define	THR_ALIGNBYTES	15
-#define	THR_ALIGN(td)	(((uintptr_t)(td) + THR_ALIGNBYTES) & ~THR_ALIGNBYTES)
+#define	PER_KSE
+#undef	PER_THREAD
+
+struct kse;
+struct pthread;
+struct tdv;
 
 /*
- * KSE Specific Data.
+ * %fs points to a struct kcb.
  */
-struct ksd {
-	void	*base;
-	long	size;
+struct kcb {
+	struct tcb		*kcb_curtcb;
+	struct kcb		*kcb_self;	/* self reference */
+	struct kse		*kcb_kse;
+	struct kse_mailbox	kcb_kmbx;
+};
+
+struct tcb {
+	struct tdv		*tcb_tdv;
+	struct pthread		*tcb_thread;
+	void			*tcb_spare[2];	/* align tcb_tmbx to 16 bytes */
+	struct kse_thr_mailbox	tcb_tmbx;
 };
 
+/*
+ * Evaluates to the byte offset of the per-kse variable name.
+ */
+#define	__kcb_offset(name)	__offsetof(struct kcb, name)
+
+/*
+ * Evaluates to the type of the per-kse variable name.
+ */
+#define	__kcb_type(name)	__typeof(((struct kcb *)0)->name)
+
+/*
+ * Evaluates to the value of the per-kse variable name.
+ */
+#define	KCB_GET64(name) ({					\
+	__kcb_type(name) __result;				\
+								\
+	u_long __i;						\
+	__asm __volatile("movq %%fs:%1, %0"			\
+	    : "=r" (__i)					\
+	    : "m" (*(u_long *)(__kcb_offset(name))));		\
+	__result = *(__kcb_type(name) *)&__i;			\
+								\
+	__result;						\
+})
+
+/*
+ * Sets the value of the per-kse variable name to value val.
+ */
+#define	KCB_SET64(name, val) ({					\
+	__kcb_type(name) __val = (val);				\
+								\
+	u_long __i;						\
+	__i = *(u_long *)&__val;				\
+	__asm __volatile("movq %1,%%fs:%0"			\
+	    : "=m" (*(u_long *)(__kcb_offset(name)))		\
+	    : "r" (__i));					\
+})
+
+static __inline u_long
+__kcb_readandclear64(volatile u_long *addr)
+{
+	u_long result;
+
+	__asm __volatile (
+	    "	xorq	%0, %0;"
+	    "	xchgq	%%fs:%1, %0;"
+	    "# __kcb_readandclear64"
+	    : "=&r" (result)
+	    : "m" (*addr));
+	return (result);
+}
+
+#define	KCB_READANDCLEAR64(name) ({				\
+	__kcb_type(name) __result;				\
+								\
+	__result = (__kcb_type(name))				\
+	    __kcb_readandclear64((u_long *)__kcb_offset(name)); \
+	__result;						\
+})
+
+
+#define	_kcb_curkcb()		KCB_GET64(kcb_self)
+#define	_kcb_curtcb()		KCB_GET64(kcb_curtcb)
+#define	_kcb_curkse()		((struct kse *)KCB_GET64(kcb_kmbx.km_udata))
+#define	_kcb_get_tmbx()		KCB_GET64(kcb_kmbx.km_curthread)
+#define	_kcb_set_tmbx(value)	KCB_SET64(kcb_kmbx.km_curthread, (void *)value)
+#define	_kcb_readandclear_tmbx() KCB_READANDCLEAR64(kcb_kmbx.km_curthread)
+
+/*
+ * The constructors.
+ */
+struct tcb	*_tcb_ctor(struct pthread *);
+void		_tcb_dtor(struct tcb *tcb);
+struct kcb	*_kcb_ctor(struct kse *);
+void		_kcb_dtor(struct kcb *);
+
+/* Called from the KSE to set its private data. */
+static __inline void
+_kcb_set(struct kcb *kcb)
+{
+	void *addr = kcb;
+
+	sysarch(AMD64_SET_FSBASE, &addr);
+}
+
+/* Get the current kcb. */
+static __inline struct kcb *
+_kcb_get(void)
+{
+	return (_kcb_curkcb());
+}
+
+static __inline struct kse_thr_mailbox *
+_kcb_critical_enter(void)
+{
+	struct kse_thr_mailbox *crit;
+
+	crit = _kcb_readandclear_tmbx();
+	return (crit);
+}
+
+static __inline void
+_kcb_critical_leave(struct kse_thr_mailbox *crit)
+{
+	_kcb_set_tmbx(crit);
+}
+
+static __inline int
+_kcb_in_critical(void)
+{
+	return (_kcb_get_tmbx() == NULL);
+}
+
+static __inline void
+_tcb_set(struct kcb *kcb, struct tcb *tcb)
+{
+	kcb->kcb_curtcb = tcb;
+}
+
+static __inline struct tcb *
+_tcb_get(void)
+{
+	return (_kcb_curtcb());
+}
+
+static __inline struct pthread *
+_get_curthread(void)
+{
+	struct tcb *tcb;
+
+	tcb = _kcb_curtcb();
+	if (tcb != NULL)
+		return (tcb->tcb_thread);
+	else
+		return (NULL);
+}
+
+static __inline struct kse *
+_get_curkse(void)
+{
+	return ((struct kse *)_kcb_curkse());
+}
+
 void _amd64_enter_uts(struct kse_mailbox *km, kse_func_t uts, void *stack,
     size_t stacksz);
 int _amd64_restore_context(mcontext_t *mc, intptr_t val, intptr_t *loc);
 int _amd64_save_context(mcontext_t *mc);
 
 static __inline int
-_thread_enter_uts(struct kse_thr_mailbox *tm, struct kse_mailbox *km)
+_thread_enter_uts(struct tcb *tcb, struct kcb *kcb)
 {
-	if (tm == NULL)
-		return (-1);
-	if (!_amd64_save_context(&tm->tm_context.uc_mcontext)) {
-		_amd64_enter_uts(km, km->km_func, km->km_stack.ss_sp,
-		    km->km_stack.ss_size);
+	int ret;
+
+	ret = _amd64_save_context(&tcb->tcb_tmbx.tm_context.uc_mcontext);
+	if (ret == 0) {
+		_amd64_enter_uts(&kcb->kcb_kmbx, kcb->kcb_kmbx.km_func,
+		    kcb->kcb_kmbx.km_stack.ss_sp,
+		    kcb->kcb_kmbx.km_stack.ss_size);
 		/* We should not reach here. */
 		return (-1);
 	}
+	else if (ret < 0)
+		return (-1);
 	return (0);
 }
 
 static __inline int
-_thread_switch(struct kse_thr_mailbox *tm, struct kse_thr_mailbox **thrp)
+_thread_switch(struct kcb *kcb, struct tcb *tcb, int setmbox)
 {
-	if (tm == NULL)
+	if ((kcb == NULL) || (tcb == NULL))
 		return (-1);
-	_amd64_restore_context(&tm->tm_context.uc_mcontext, (intptr_t)tm,
-	    (intptr_t*)thrp);
+	kcb->kcb_curtcb = tcb;
+	if (setmbox != 0)
+		_amd64_restore_context(&tcb->tcb_tmbx.tm_context.uc_mcontext,
+		    (intptr_t)&tcb->tcb_tmbx,
+		    (intptr_t *)&kcb->kcb_kmbx.km_curthread);
+	else
+		_amd64_restore_context(&tcb->tcb_tmbx.tm_context.uc_mcontext,
+		    0, NULL);
 	/* We should not reach here. */
 	return (-1);
 }
-
 #endif