[RFT] final cur of tr based current for -ac8

[RFT] final cur of tr based current for -ac8

[Benjamin LaHaise]

Here's hopefully the end of the experimental current games in -ac8.  This 
one boots on UP and SMP unlike the last couple.  Widespread testing would 
be appreciated, especially considering that 2.4.13-ac8 is unusable on x86 
without this patch.  If someone feels like automating the per-cpu data 
log2 for the assembly, it'd be nice, but since there's a hack in to make 
the compiler complain when the size gets out of whack...

Just to remind folks: this patch takes the per-cpu scheduler data out of 
sched.c and into per_cpu.h where people probably want to move many of the 
NR_CPUS array datums to.  smp_processor_id() now takes about 3 pairable 
instructions, and is marked pure.  get_current() is marked const and a few 
places have replaced current->processor with smp_processor_id().  This 
should allow gcc to make better optimizations of sequences that reference 
current or need the cpu #.  Cheers,

		-ben
-- 
Fish.

... v2.4.13-ac8+tr.3.diff ...

diff -urN kernels/2.4/v2.4.13-ac8/arch/i386/kernel/entry.S v2.4.13-ac8+tr.3/arch/i386/kernel/entry.S
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/entry.S	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.3/arch/i386/kernel/entry.S	Thu Nov  8 22:27:30 2001
@@ -45,6 +45,7 @@
 #include <linux/linkage.h>
 #include <asm/segment.h>
 #include <asm/smp.h>
+#include <asm/current_asm.h>
 
 EBX		= 0x00
 ECX		= 0x04
@@ -134,9 +135,6 @@
 	.long 3b,6b;	\
 .previous
 
-#define GET_CURRENT(reg) \
-	movl %cr2, reg
-
 ENTRY(lcall7)
 	pushfl			# We get a different stack layout with call gates,
 	pushl %eax		# which has to be cleaned up later..
@@ -149,7 +147,7 @@
 	movl %ecx,CS(%esp)	#
 	movl %esp,%ebx
 	pushl %ebx
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	movl exec_domain(%ebx),%edx	# Get the execution domain
 	movl 4(%edx),%edx	# Get the lcall7 handler for the domain
 	pushl $0x7
@@ -170,7 +168,7 @@
 	movl %ecx,CS(%esp)	#
 	movl %esp,%ebx
 	pushl %ebx
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	movl exec_domain(%ebx),%edx	# Get the execution domain
 	movl 4(%edx),%edx	# Get the lcall7 handler for the domain
 	pushl $0x27
@@ -184,7 +182,7 @@
 	pushl %ebx
 	call SYMBOL_NAME(schedule_tail)
 	addl $4, %esp
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	testb $0x02,tsk_ptrace(%ebx)	# PT_TRACESYS
 	jne tracesys_exit
 	jmp	ret_from_sys_call
@@ -199,7 +197,7 @@
 ENTRY(system_call)
 	pushl %eax			# save orig_eax
 	SAVE_ALL
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	cmpl $(NR_syscalls),%eax
 	jae badsys
 	testb $0x02,tsk_ptrace(%ebx)	# PT_TRACESYS
@@ -251,7 +249,7 @@
 
 	ALIGN
 ENTRY(ret_from_intr)
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 ret_from_exception:
 	movl EFLAGS(%esp),%eax		# mix EFLAGS and CS
 	movb CS(%esp),%al
@@ -297,7 +295,7 @@
 	movl %edx,%ds
 2:	call *%edi
 	addl $8,%esp
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	jmp ret_from_exception
 
 ENTRY(coprocessor_error)
@@ -313,7 +311,7 @@
 ENTRY(device_not_available)
 	pushl $-1		# mark this as an int
 	SAVE_ALL
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	movl %cr0,%eax
 	testl $0x4,%eax			# EM (math emulation bit)
 	jne device_not_available_emulate
diff -urN kernels/2.4/v2.4.13-ac8/arch/i386/kernel/ldt.c v2.4.13-ac8+tr.3/arch/i386/kernel/ldt.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/ldt.c	Thu Nov  1 16:39:57 2001
+++ v2.4.13-ac8+tr.3/arch/i386/kernel/ldt.c	Thu Nov  8 18:25:56 2001
@@ -12,11 +12,13 @@
 #include <linux/smp.h>
 #include <linux/smp_lock.h>
 #include <linux/vmalloc.h>
+#include <linux/per_cpu.h>
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
 #include <asm/ldt.h>
 #include <asm/desc.h>
+#include <asm/descfn.h>
 
 /*
  * read_ldt() is not really atomic - this is not a problem since
diff -urN kernels/2.4/v2.4.13-ac8/arch/i386/kernel/nmi.c v2.4.13-ac8+tr.3/arch/i386/kernel/nmi.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/nmi.c	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.3/arch/i386/kernel/nmi.c	Sat Nov 10 14:00:33 2001
@@ -264,7 +264,7 @@
 	/*
 	 * NMI can interrupt page faults, use hard_get_current.
 	 */
-	int sum, cpu = hard_get_current()->processor;
+	int sum, cpu = hard_smp_processor_id();
 
 	sum = apic_timer_irqs[cpu];
 
diff -urN kernels/2.4/v2.4.13-ac8/arch/i386/kernel/setup.c v2.4.13-ac8+tr.3/arch/i386/kernel/setup.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/setup.c	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.3/arch/i386/kernel/setup.c	Sat Nov 10 14:01:41 2001
@@ -108,6 +108,7 @@
 #include <asm/cobalt.h>
 #include <asm/msr.h>
 #include <asm/desc.h>
+#include <asm/descfn.h>
 #include <asm/e820.h>
 #include <asm/dma.h>
 #include <asm/mpspec.h>
@@ -2852,8 +2853,9 @@
  */
 void __init cpu_init (void)
 {
-	int nr = smp_processor_id();
+	int nr = hard_smp_processor_id();
 	struct tss_struct * t = &init_tss[nr];
+	struct task_struct *cur;
 
 	if (test_and_set_bit(nr, &cpu_initialized)) {
 		printk(KERN_WARNING "CPU#%d already initialized!\n", nr);
@@ -2884,16 +2886,18 @@
 	 * set up and load the per-CPU TSS and LDT
 	 */
 	atomic_inc(&init_mm.mm_count);
-	current->active_mm = &init_mm;
-	if(current->mm)
+	cur = hard_get_current();
+	cur->active_mm = &init_mm;
+	if(cur->mm)
 		BUG();
-	enter_lazy_tlb(&init_mm, current, nr);
+	enter_lazy_tlb(&init_mm, cur, nr);
 
-	t->esp0 = current->thread.esp0;
+	t->esp0 = cur->thread.esp0;
 	set_tss_desc(nr,t);
 	gdt_table[__TSS(nr)].b &= 0xfffffdff;
 	load_TR(nr);
 	load_LDT(&init_mm);
+	set_current(cur);
 
 	/*
 	 * Clear all 6 debug registers:
@@ -2908,8 +2912,8 @@
 	/*
 	 * Force FPU initialization:
 	 */
-	current->flags &= ~PF_USEDFPU;
-	current->used_math = 0;
+	cur->flags &= ~PF_USEDFPU;
+	cur->used_math = 0;
 	stts();
 }
 
diff -urN kernels/2.4/v2.4.13-ac8/arch/i386/lib/getuser.S v2.4.13-ac8+tr.3/arch/i386/lib/getuser.S
--- kernels/2.4/v2.4.13-ac8/arch/i386/lib/getuser.S	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.3/arch/i386/lib/getuser.S	Wed Nov  7 22:33:07 2001
@@ -8,6 +8,7 @@
  * return an error value in addition to the "real"
  * return value.
  */
+#include <asm/current_asm.h>
 
 /*
  * __get_user_X
@@ -27,7 +28,6 @@
 .align 4
 .globl __get_user_1
 __get_user_1:
-	movl %cr2,%edx
 	cmpl addr_limit(%edx),%eax
 	jae bad_get_user
 1:	movzbl (%eax),%edx
@@ -39,7 +39,6 @@
 __get_user_2:
 	addl $1,%eax
 	jc bad_get_user
-	movl %cr2,%edx
 	cmpl addr_limit(%edx),%eax
 	jae bad_get_user
 2:	movzwl -1(%eax),%edx
@@ -51,7 +50,6 @@
 __get_user_4:
 	addl $3,%eax
 	jc bad_get_user
-	movl %cr2,%edx
 	cmpl addr_limit(%edx),%eax
 	jae bad_get_user
 3:	movl -3(%eax),%edx
diff -urN kernels/2.4/v2.4.13-ac8/arch/i386/mm/fault.c v2.4.13-ac8+tr.3/arch/i386/mm/fault.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/mm/fault.c	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.3/arch/i386/mm/fault.c	Sat Nov 10 14:03:13 2001
@@ -25,6 +25,7 @@
 #include <asm/uaccess.h>
 #include <asm/pgalloc.h>
 #include <asm/hardirq.h>
+#include <asm/desc.h>
 
 extern void die(const char *,struct pt_regs *,long);
 
@@ -148,7 +149,6 @@
 }
 
 asmlinkage void do_invalid_op(struct pt_regs *, unsigned long);
-extern unsigned long idt;
 
 /*
  * This routine handles page faults.  It determines the address,
@@ -173,9 +173,11 @@
 
 	/* get the address */
 	__asm__("movl %%cr2,%0":"=r" (address));
+
 	/* and restore current */
-	tsk = hard_get_current();
-	set_current(tsk);
+	set_current(hard_get_current());
+	tsk = current;
+
 
 	/* It's safe to allow irq's after cr2 has been saved */
 	if (regs->eflags & X86_EFLAGS_IF)
@@ -309,7 +311,7 @@
 	if (boot_cpu_data.f00f_bug) {
 		unsigned long nr;
 		
-		nr = (address - idt) >> 3;
+		nr = (address - (unsigned long)idt) >> 3;
 
 		if (nr == 6) {
 			do_invalid_op(regs, 0);
diff -urN kernels/2.4/v2.4.13-ac8/include/asm-i386/current.h v2.4.13-ac8+tr.3/include/asm-i386/current.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/current.h	Tue Nov  6 20:43:27 2001
+++ v2.4.13-ac8+tr.3/include/asm-i386/current.h	Sat Nov 10 12:50:47 2001
@@ -1,28 +1,23 @@
 #ifndef _I386_CURRENT_H
 #define _I386_CURRENT_H
 
-struct task_struct;
+#include <linux/per_cpu.h>
 
-static inline struct task_struct * get_current(void)
+static inline struct task_struct *get_current(void) __attribute__((const));
+static inline struct task_struct *get_current(void)
 {
-	struct task_struct *tsk;
-	__asm__("movl %%cr2,%0;": "=r" (tsk));
-	return tsk;
+	return per_data(smp_processor_id())->curr;
 }
 
 /* for within NMI, do_page_fault, cpu_init */
 static inline struct task_struct * hard_get_current(void)
 {
-	struct task_struct **ptsk;
-	__asm__("andl %%esp,%0; ":"=r" (ptsk) : "0" (~8191UL));
-	return *ptsk;
+	return per_data(hard_smp_processor_id())->curr;
 }
 
 static inline void set_current(struct task_struct *tsk)
 {
-	__asm__("movl %0,%%cr2;"
-			: /* no output */
-			:"r" (tsk));
+	/* This hook is needed if schedule() doesn't update the per_cpu cur */;
 }
    
 /* Note: the implementation is hardcoded into arch/i386/lib/getuser.S */
diff -urN kernels/2.4/v2.4.13-ac8/include/asm-i386/current_asm.h v2.4.13-ac8+tr.3/include/asm-i386/current_asm.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/current_asm.h	Wed Dec 31 19:00:00 1969
+++ v2.4.13-ac8+tr.3/include/asm-i386/current_asm.h	Sat Nov 10 12:48:47 2001
@@ -0,0 +1,30 @@
+/* asm/current_asm.h
+ */
+#ifndef __ASM__CURRENT_ASM_H
+#define __ASM__CURRENT_ASM_H
+
+#include <linux/config.h>
+#include <linux/per_cpu.h>
+#include <asm/desc.h>
+
+#if 1 /*def CONFIG_SMP*/
+/* Pass in the long and short versions of the register.
+ * eg GET_CURRENT(%ebx,%bx)
+ * All of this braindamage comes to us c/o a bug in gas: the
+ * opcode we want should actually be generated by strl, but 
+ * unfortunately gas doesn't realize that the operand size 
+ * prefix applies to str.  Please take a wet noodle and thread 
+ * it into my eye as that will be less painful than dealing 
+ * with this mess.  -ben
+ */
+#define GET_CURRENT(reg,regw)				\
+	str regw					\
+	; shll $LOG2_PER_CPU_SIZE-2,reg			\
+	; aligned_data_adjusted = aligned_data-(__FIRST_TSS_ENTRY << (3 + LOG2_PER_CPU_SIZE - 2))	\
+	; movl aligned_data_adjusted(reg),reg
+
+#else
+#define GET_CURRENT(reg,regw)	movl (aligned_data),reg
+#endif
+
+#endif /* __ASM__CURRENT_ASM_H */
diff -urN kernels/2.4/v2.4.13-ac8/include/asm-i386/desc.h v2.4.13-ac8+tr.3/include/asm-i386/desc.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/desc.h	Tue Nov  6 20:43:27 2001
+++ v2.4.13-ac8+tr.3/include/asm-i386/desc.h	Tue Nov  6 21:21:32 2001
@@ -68,40 +68,6 @@
 
 #define __load_LDT(n) __asm__ __volatile__("lldt %%ax"::"a" (__LDT(n)<<3))
 
-/*
- * This is the ldt that every process will get unless we need
- * something other than this.
- */
-extern struct desc_struct default_ldt[];
-extern void set_intr_gate(unsigned int irq, void * addr);
-extern void set_ldt_desc(unsigned int n, void *addr, unsigned int size);
-extern void set_tss_desc(unsigned int n, void *addr);
-
-static inline void clear_LDT(void)
-{
-	int cpu = smp_processor_id();
-	set_ldt_desc(cpu, &default_ldt[0], 5);
-	__load_LDT(cpu);
-}
-
-/*
- * load one particular LDT into the current CPU
- */
-static inline void load_LDT (struct mm_struct *mm)
-{
-	int cpu = smp_processor_id();
-	void *segments = mm->context.segments;
-	int count = LDT_ENTRIES;
-
-	if (!segments) {
-		segments = &default_ldt[0];
-		count = 5;
-	}
-		
-	set_ldt_desc(cpu, segments, count);
-	__load_LDT(cpu);
-}
-
 #endif /* !__ASSEMBLY__ */
 
 #endif
diff -urN kernels/2.4/v2.4.13-ac8/include/asm-i386/descfn.h v2.4.13-ac8+tr.3/include/asm-i386/descfn.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/descfn.h	Wed Dec 31 19:00:00 1969
+++ v2.4.13-ac8+tr.3/include/asm-i386/descfn.h	Tue Nov  6 21:23:59 2001
@@ -0,0 +1,42 @@
+#ifndef __ARCH_DESCFN_H
+#define __ARCH_DESCFN_H
+
+#ifndef __ARCH_DESC_H
+#include <asm/desc.h>
+#endif
+
+/*
+ * This is the ldt that every process will get unless we need
+ * something other than this.
+ */
+extern struct desc_struct default_ldt[];
+extern void set_intr_gate(unsigned int irq, void * addr);
+extern void set_ldt_desc(unsigned int n, void *addr, unsigned int size);
+extern void set_tss_desc(unsigned int n, void *addr);
+
+static inline void clear_LDT(void)
+{
+	int cpu = smp_processor_id();
+	set_ldt_desc(cpu, &default_ldt[0], 5);
+	__load_LDT(cpu);
+}
+
+/*
+ * load one particular LDT into the current CPU
+ */
+static inline void load_LDT (struct mm_struct *mm)
+{
+	int cpu = smp_processor_id();
+	void *segments = mm->context.segments;
+	int count = LDT_ENTRIES;
+
+	if (!segments) {
+		segments = &default_ldt[0];
+		count = 5;
+	}
+		
+	set_ldt_desc(cpu, segments, count);
+	__load_LDT(cpu);
+}
+
+#endif /* __ARCH_DESCFN_H */
diff -urN kernels/2.4/v2.4.13-ac8/include/asm-i386/mmu_context.h v2.4.13-ac8+tr.3/include/asm-i386/mmu_context.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/mmu_context.h	Tue Nov  6 21:23:24 2001
+++ v2.4.13-ac8+tr.3/include/asm-i386/mmu_context.h	Sat Nov 10 12:51:14 2001
@@ -5,6 +5,7 @@
 #include <asm/desc.h>
 #include <asm/atomic.h>
 #include <asm/pgalloc.h>
+#include <asm/descfn.h>
 
 /*
  * possibly do the LDT unload here?
diff -urN kernels/2.4/v2.4.13-ac8/include/asm-i386/smp.h v2.4.13-ac8+tr.3/include/asm-i386/smp.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/smp.h	Tue Nov  6 21:00:35 2001
+++ v2.4.13-ac8+tr.3/include/asm-i386/smp.h	Sat Nov 10 14:04:50 2001
@@ -8,6 +8,7 @@
 #include <linux/config.h>
 #include <linux/threads.h>
 #include <linux/ptrace.h>
+#include <asm/desc.h>
 #endif
 
 #ifdef CONFIG_X86_LOCAL_APIC
@@ -101,7 +102,20 @@
  * so this is correct in the x86 case.
  */
 
-#define smp_processor_id() (current->processor)
+static unsigned get_TR(void) __attribute__ ((pure));
+static unsigned get_TR(void)
+{
+	unsigned tr;
+	/* The PAIN!  The HORROR!
+	 * Technically this is wrong, wrong, wrong, but 
+	 * gas doesn't know about strl.  *sigh*  Please 
+	 * flog them with a wet noodle repeatedly.  -ben
+	 */
+	__asm__ __volatile__("str %w0" : "=r" (tr));
+	return tr;
+}
+
+#define smp_processor_id()	( ((get_TR() >> 3) - __FIRST_TSS_ENTRY) >> 2 )
 
 static __inline int hard_smp_processor_id(void)
 {
diff -urN kernels/2.4/v2.4.13-ac8/include/asm-i386/uaccess.h v2.4.13-ac8+tr.3/include/asm-i386/uaccess.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/uaccess.h	Wed Nov  7 18:09:12 2001
+++ v2.4.13-ac8+tr.3/include/asm-i386/uaccess.h	Sat Nov 10 12:51:14 2001
@@ -109,7 +109,7 @@
 #define __get_user_x(size,ret,x,ptr) \
 	__asm__ __volatile__("call __get_user_" #size \
 		:"=a" (ret),"=d" (x) \
-		:"0" (ptr))
+		:"0" (ptr), "1" (current))
 
 /* Careful: we have to cast the result to the type of the pointer for sign reasons */
 #define get_user(x,ptr)							\
diff -urN kernels/2.4/v2.4.13-ac8/include/linux/per_cpu.h v2.4.13-ac8+tr.3/include/linux/per_cpu.h
--- kernels/2.4/v2.4.13-ac8/include/linux/per_cpu.h	Wed Dec 31 19:00:00 1969
+++ v2.4.13-ac8+tr.3/include/linux/per_cpu.h	Thu Nov  8 22:15:26 2001
@@ -0,0 +1,32 @@
+#ifndef __LINUX__PER_CPU__H
+#define __LINUX__PER_CPU__H
+
+#define LOG2_PER_CPU_SIZE	8
+#define PER_CPU_SIZE		(1 << LOG2_PER_CPU_SIZE)
+
+#ifndef __ASSEMBLY__
+struct task_struct;
+
+struct per_cpu_data {
+	/* Assembly code relies on curr being the first member of this 
+	 * structure.  Please change it if this gets rearranged.
+	 */
+	struct task_struct	*curr;
+	cycles_t		last_schedule;
+};
+
+union aligned_data {
+	struct per_cpu_data	data;
+	char __pad [PER_CPU_SIZE];
+
+	/* Make sure the padding is large enough by forcing an error 
+	 * if it isn't.  -ben
+	 */
+	char __pad2 [PER_CPU_SIZE - sizeof(struct per_cpu_data)];
+};
+
+extern union aligned_data aligned_data[];
+
+#define per_data(nr)	(&aligned_data[nr].data)
+#endif
+#endif
diff -urN kernels/2.4/v2.4.13-ac8/init/main.c v2.4.13-ac8+tr.3/init/main.c
--- kernels/2.4/v2.4.13-ac8/init/main.c	Tue Nov  6 20:43:28 2001
+++ v2.4.13-ac8+tr.3/init/main.c	Sat Nov 10 13:11:06 2001
@@ -635,7 +635,6 @@
  * Interrupts are still disabled. Do necessary setups, then
  * enable them
  */
-	lock_kernel();
 	printk(linux_banner);
 	setup_arch(&command_line);
 	printk("Kernel command line: %s\n", saved_command_line);
@@ -646,6 +645,13 @@
 	softirq_init();
 	time_init();
 
+	/* At the very least, this has to come after trap_init as x86
+	 * needs to perform CPU setup before current is valid.  This 
+	 * should be okay as we're still running with interrupts disabled 
+	 * and no other CPUs are up yet.  -ben
+	 */
+	lock_kernel();
+
 	/*
 	 * HACK ALERT! This is early. We're enabling the console before
 	 * we've done PCI setups etc, and console_init() must be aware of
diff -urN kernels/2.4/v2.4.13-ac8/kernel/sched.c v2.4.13-ac8+tr.3/kernel/sched.c
--- kernels/2.4/v2.4.13-ac8/kernel/sched.c	Tue Nov  6 20:43:28 2001
+++ v2.4.13-ac8+tr.3/kernel/sched.c	Wed Nov  7 17:49:00 2001
@@ -28,6 +28,7 @@
 #include <linux/kernel_stat.h>
 #include <linux/completion.h>
 #include <linux/prefetch.h>
+#include <linux/per_cpu.h>
 
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
@@ -97,16 +98,12 @@
  * We align per-CPU scheduling data on cacheline boundaries,
  * to prevent cacheline ping-pong.
  */
-static union {
-	struct schedule_data {
-		struct task_struct * curr;
-		cycles_t last_schedule;
-	} schedule_data;
-	char __pad [SMP_CACHE_BYTES];
-} aligned_data [NR_CPUS] __cacheline_aligned = { {{&init_task,0}}};
+union aligned_data aligned_data[NR_CPUS] __cacheline_aligned = {
+	{{&init_task,0}}
+};
 
-#define cpu_curr(cpu) aligned_data[(cpu)].schedule_data.curr
-#define last_schedule(cpu) aligned_data[(cpu)].schedule_data.last_schedule
+#define cpu_curr(cpu)		per_data(cpu)->curr
+#define last_schedule(cpu)	per_data(cpu)->last_schedule
 
 struct kernel_stat kstat;
 extern struct task_struct *child_reaper;
@@ -532,7 +529,7 @@
  */
 asmlinkage void schedule(void)
 {
-	struct schedule_data * sched_data;
+	struct per_cpu_data * sched_data;
 	struct task_struct *prev, *next, *p;
 	struct list_head *tmp;
 	int this_cpu, c;
@@ -543,7 +540,7 @@
 	if (!current->active_mm) BUG();
 need_resched_back:
 	prev = current;
-	this_cpu = prev->processor;
+	this_cpu = smp_processor_id();	/* This better than current->processor on up */
 
 	if (in_interrupt())
 		goto scheduling_in_interrupt;
@@ -554,7 +551,7 @@
 	 * 'sched_data' is protected by the fact that we can run
 	 * only one process per CPU.
 	 */
-	sched_data = & aligned_data[this_cpu].schedule_data;
+	sched_data = per_data(this_cpu);
 
 	spin_lock_irq(&runqueue_lock);
 
@@ -1057,7 +1054,7 @@
 	// Subtract non-idle processes running on other CPUs.
 	for (i = 0; i < smp_num_cpus; i++) {
 		int cpu = cpu_logical_map(i);
-		if (aligned_data[cpu].schedule_data.curr != idle_task(cpu))
+		if (per_data(cpu)->curr != idle_task(cpu))
 			nr_pending--;
 	}
 #else
@@ -1309,17 +1306,18 @@
 
 void __init init_idle(void)
 {
-	struct schedule_data * sched_data;
-	sched_data = &aligned_data[smp_processor_id()].schedule_data;
+	struct per_cpu_data * sched_data;
+	int cpu = smp_processor_id();
+	sched_data = per_data(cpu);
 
 	if (current != &init_task && task_on_runqueue(current)) {
 		printk("UGH! (%d:%d) was on the runqueue, removing.\n",
-			smp_processor_id(), current->pid);
+			cpu, current->pid);
 		del_from_runqueue(current);
 	}
 	sched_data->curr = current;
 	sched_data->last_schedule = get_cycles();
-	clear_bit(current->processor, &wait_init_idle);
+	clear_bit(cpu, &wait_init_idle);
 }
 
 extern void init_timervecs (void);

Re: [RFT] final cur of tr based current for -ac8

[John Levon]

On Sat, Nov 10, 2001 at 02:14:40PM -0500, Benjamin LaHaise wrote:

> Here's hopefully the end of the experimental current games in -ac8.  This 
> one boots on UP and SMP unlike the last couple.  Widespread testing would 
> be appreciated, especially considering that 2.4.13-ac8 is unusable on x86 

Needs this :

--- kernel/ksyms.c.old	Sat Nov 10 20:36:44 2001
+++ kernel/ksyms.c	Sat Nov 10 20:38:04 2001
@@ -440,6 +440,7 @@
 #endif
 EXPORT_SYMBOL(kstat);
 EXPORT_SYMBOL(nr_running);
+EXPORT_SYMBOL(aligned_data);
 
 /* misc */
 EXPORT_SYMBOL(panic);


I'm running with the patch now. Seems stable (ac8 crashed pretty quickly for me).

thanks
john

Re: [RFT] final cur of tr based current for -ac8

[Benjamin LaHaise]

On Sat, Nov 10, 2001 at 08:33:48PM +0000, John Levon wrote:
> I'm running with the patch now. Seems stable (ac8 crashed pretty quickly for me).

Thanks...  I seem to have blotched the SMP side of things (again) which this 
might fix (including the symbol export from you).  Also, Michael Barabanov 
came up with a patch using the same trick, although I haven't seen it.

		-ben

... v2.4.13-ac8+tr.4.diff ...
diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/kernel/entry.S v2.4.13-ac8+tr.4/arch/i386/kernel/entry.S
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/entry.S	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.4/arch/i386/kernel/entry.S	Thu Nov  8 22:27:30 2001
@@ -45,6 +45,7 @@
 #include <linux/linkage.h>
 #include <asm/segment.h>
 #include <asm/smp.h>
+#include <asm/current_asm.h>
 
 EBX		= 0x00
 ECX		= 0x04
@@ -134,9 +135,6 @@
 	.long 3b,6b;	\
 .previous
 
-#define GET_CURRENT(reg) \
-	movl %cr2, reg
-
 ENTRY(lcall7)
 	pushfl			# We get a different stack layout with call gates,
 	pushl %eax		# which has to be cleaned up later..
@@ -149,7 +147,7 @@
 	movl %ecx,CS(%esp)	#
 	movl %esp,%ebx
 	pushl %ebx
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	movl exec_domain(%ebx),%edx	# Get the execution domain
 	movl 4(%edx),%edx	# Get the lcall7 handler for the domain
 	pushl $0x7
@@ -170,7 +168,7 @@
 	movl %ecx,CS(%esp)	#
 	movl %esp,%ebx
 	pushl %ebx
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	movl exec_domain(%ebx),%edx	# Get the execution domain
 	movl 4(%edx),%edx	# Get the lcall7 handler for the domain
 	pushl $0x27
@@ -184,7 +182,7 @@
 	pushl %ebx
 	call SYMBOL_NAME(schedule_tail)
 	addl $4, %esp
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	testb $0x02,tsk_ptrace(%ebx)	# PT_TRACESYS
 	jne tracesys_exit
 	jmp	ret_from_sys_call
@@ -199,7 +197,7 @@
 ENTRY(system_call)
 	pushl %eax			# save orig_eax
 	SAVE_ALL
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	cmpl $(NR_syscalls),%eax
 	jae badsys
 	testb $0x02,tsk_ptrace(%ebx)	# PT_TRACESYS
@@ -251,7 +249,7 @@
 
 	ALIGN
 ENTRY(ret_from_intr)
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 ret_from_exception:
 	movl EFLAGS(%esp),%eax		# mix EFLAGS and CS
 	movb CS(%esp),%al
@@ -297,7 +295,7 @@
 	movl %edx,%ds
 2:	call *%edi
 	addl $8,%esp
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	jmp ret_from_exception
 
 ENTRY(coprocessor_error)
@@ -313,7 +311,7 @@
 ENTRY(device_not_available)
 	pushl $-1		# mark this as an int
 	SAVE_ALL
-	GET_CURRENT(%ebx)
+	GET_CURRENT(%ebx,%bx)
 	movl %cr0,%eax
 	testl $0x4,%eax			# EM (math emulation bit)
 	jne device_not_available_emulate
diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/kernel/ldt.c v2.4.13-ac8+tr.4/arch/i386/kernel/ldt.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/ldt.c	Thu Nov  1 16:39:57 2001
+++ v2.4.13-ac8+tr.4/arch/i386/kernel/ldt.c	Thu Nov  8 18:25:56 2001
@@ -12,11 +12,13 @@
 #include <linux/smp.h>
 #include <linux/smp_lock.h>
 #include <linux/vmalloc.h>
+#include <linux/per_cpu.h>
 
 #include <asm/uaccess.h>
 #include <asm/system.h>
 #include <asm/ldt.h>
 #include <asm/desc.h>
+#include <asm/descfn.h>
 
 /*
  * read_ldt() is not really atomic - this is not a problem since
diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/kernel/nmi.c v2.4.13-ac8+tr.4/arch/i386/kernel/nmi.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/nmi.c	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.4/arch/i386/kernel/nmi.c	Sat Nov 10 14:00:33 2001
@@ -264,7 +264,7 @@
 	/*
 	 * NMI can interrupt page faults, use hard_get_current.
 	 */
-	int sum, cpu = hard_get_current()->processor;
+	int sum, cpu = hard_smp_processor_id();
 
 	sum = apic_timer_irqs[cpu];
 
diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/kernel/setup.c v2.4.13-ac8+tr.4/arch/i386/kernel/setup.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/setup.c	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.4/arch/i386/kernel/setup.c	Sat Nov 10 16:56:23 2001
@@ -108,6 +108,7 @@
 #include <asm/cobalt.h>
 #include <asm/msr.h>
 #include <asm/desc.h>
+#include <asm/descfn.h>
 #include <asm/e820.h>
 #include <asm/dma.h>
 #include <asm/mpspec.h>
@@ -2852,7 +2853,8 @@
  */
 void __init cpu_init (void)
 {
-	int nr = smp_processor_id();
+	struct task_struct *cur = hard_get_current();
+	int nr = cur->processor;
 	struct tss_struct * t = &init_tss[nr];
 
 	if (test_and_set_bit(nr, &cpu_initialized)) {
@@ -2884,17 +2886,19 @@
 	 * set up and load the per-CPU TSS and LDT
 	 */
 	atomic_inc(&init_mm.mm_count);
-	current->active_mm = &init_mm;
-	if(current->mm)
+	cur->active_mm = &init_mm;
+	if(cur->mm)
 		BUG();
-	enter_lazy_tlb(&init_mm, current, nr);
+	enter_lazy_tlb(&init_mm, cur, nr);
 
-	t->esp0 = current->thread.esp0;
+	t->esp0 = cur->thread.esp0;
 	set_tss_desc(nr,t);
 	gdt_table[__TSS(nr)].b &= 0xfffffdff;
 	load_TR(nr);
 	load_LDT(&init_mm);
 
+	set_current(cur);
+
 	/*
 	 * Clear all 6 debug registers:
 	 */
@@ -2908,8 +2912,8 @@
 	/*
 	 * Force FPU initialization:
 	 */
-	current->flags &= ~PF_USEDFPU;
-	current->used_math = 0;
+	cur->flags &= ~PF_USEDFPU;
+	cur->used_math = 0;
 	stts();
 }
 
diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/kernel/smpboot.c v2.4.13-ac8+tr.4/arch/i386/kernel/smpboot.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/smpboot.c	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.4/arch/i386/kernel/smpboot.c	Sat Nov 10 15:56:44 2001
@@ -507,14 +507,14 @@
 }
 
 /* which physical APIC ID maps to which logical CPU number */
-volatile int physical_apicid_2_cpu[MAX_APICID];
+volatile int physical_apicid_to_cpu[MAX_APICID];
 /* which logical CPU number maps to which physical APIC ID */
-volatile int cpu_2_physical_apicid[NR_CPUS];
+volatile int cpu_to_physical_apicid[NR_CPUS];
 
 /* which logical APIC ID maps to which logical CPU number */
-volatile int logical_apicid_2_cpu[MAX_APICID];
+volatile int logical_apicid_to_cpu[MAX_APICID];
 /* which logical CPU number maps to which logical APIC ID */
-volatile int cpu_2_logical_apicid[NR_CPUS];
+volatile int cpu_to_logical_apicid[NR_CPUS];
 
 static inline void init_cpu_to_apicid(void)
 /* Initialize all maps between cpu number and apicids */
@@ -522,12 +522,12 @@
 	int apicid, cpu;
 
 	for (apicid = 0; apicid < MAX_APICID; apicid++) {
-		physical_apicid_2_cpu[apicid] = -1;
-		logical_apicid_2_cpu[apicid] = -1;
+		physical_apicid_to_cpu[apicid] = -1;
+		logical_apicid_to_cpu[apicid] = -1;
 	}
 	for (cpu = 0; cpu < NR_CPUS; cpu++) {
-		cpu_2_physical_apicid[cpu] = -1;
-		cpu_2_logical_apicid[cpu] = -1;
+		cpu_to_physical_apicid[cpu] = -1;
+		cpu_to_logical_apicid[cpu] = -1;
 	}
 }
 
@@ -538,11 +538,11 @@
  */
 {
 	if (clustered_apic_mode) {
-		logical_apicid_2_cpu[apicid] = cpu;	
-		cpu_2_logical_apicid[cpu] = apicid;
+		logical_apicid_to_cpu[apicid] = cpu;	
+		cpu_to_logical_apicid[cpu] = apicid;
 	} else {
-		physical_apicid_2_cpu[apicid] = cpu;	
-		cpu_2_physical_apicid[cpu] = apicid;
+		physical_apicid_to_cpu[apicid] = cpu;	
+		cpu_to_physical_apicid[cpu] = apicid;
 	}
 }
 
@@ -553,11 +553,11 @@
  */
 {
 	if (clustered_apic_mode) {
-		logical_apicid_2_cpu[apicid] = -1;	
-		cpu_2_logical_apicid[cpu] = -1;
+		logical_apicid_to_cpu[apicid] = -1;	
+		cpu_to_logical_apicid[cpu] = -1;
 	} else {
-		physical_apicid_2_cpu[apicid] = -1;	
-		cpu_2_physical_apicid[cpu] = -1;
+		physical_apicid_to_cpu[apicid] = -1;	
+		cpu_to_physical_apicid[cpu] = -1;
 	}
 }
 
diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/lib/getuser.S v2.4.13-ac8+tr.4/arch/i386/lib/getuser.S
--- kernels/2.4/v2.4.13-ac8/arch/i386/lib/getuser.S	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.4/arch/i386/lib/getuser.S	Wed Nov  7 22:33:07 2001
@@ -8,6 +8,7 @@
  * return an error value in addition to the "real"
  * return value.
  */
+#include <asm/current_asm.h>
 
 /*
  * __get_user_X
@@ -27,7 +28,6 @@
 .align 4
 .globl __get_user_1
 __get_user_1:
-	movl %cr2,%edx
 	cmpl addr_limit(%edx),%eax
 	jae bad_get_user
 1:	movzbl (%eax),%edx
@@ -39,7 +39,6 @@
 __get_user_2:
 	addl $1,%eax
 	jc bad_get_user
-	movl %cr2,%edx
 	cmpl addr_limit(%edx),%eax
 	jae bad_get_user
 2:	movzwl -1(%eax),%edx
@@ -51,7 +50,6 @@
 __get_user_4:
 	addl $3,%eax
 	jc bad_get_user
-	movl %cr2,%edx
 	cmpl addr_limit(%edx),%eax
 	jae bad_get_user
 3:	movl -3(%eax),%edx
diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/mm/fault.c v2.4.13-ac8+tr.4/arch/i386/mm/fault.c
--- kernels/2.4/v2.4.13-ac8/arch/i386/mm/fault.c	Tue Nov  6 20:43:22 2001
+++ v2.4.13-ac8+tr.4/arch/i386/mm/fault.c	Sat Nov 10 14:03:13 2001
@@ -25,6 +25,7 @@
 #include <asm/uaccess.h>
 #include <asm/pgalloc.h>
 #include <asm/hardirq.h>
+#include <asm/desc.h>
 
 extern void die(const char *,struct pt_regs *,long);
 
@@ -148,7 +149,6 @@
 }
 
 asmlinkage void do_invalid_op(struct pt_regs *, unsigned long);
-extern unsigned long idt;
 
 /*
  * This routine handles page faults.  It determines the address,
@@ -173,9 +173,11 @@
 
 	/* get the address */
 	__asm__("movl %%cr2,%0":"=r" (address));
+
 	/* and restore current */
-	tsk = hard_get_current();
-	set_current(tsk);
+	set_current(hard_get_current());
+	tsk = current;
+
 
 	/* It's safe to allow irq's after cr2 has been saved */
 	if (regs->eflags & X86_EFLAGS_IF)
@@ -309,7 +311,7 @@
 	if (boot_cpu_data.f00f_bug) {
 		unsigned long nr;
 		
-		nr = (address - idt) >> 3;
+		nr = (address - (unsigned long)idt) >> 3;
 
 		if (nr == 6) {
 			do_invalid_op(regs, 0);
diff -ur kernels/2.4/v2.4.13-ac8/include/asm-i386/current.h v2.4.13-ac8+tr.4/include/asm-i386/current.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/current.h	Tue Nov  6 20:43:27 2001
+++ v2.4.13-ac8+tr.4/include/asm-i386/current.h	Sat Nov 10 16:32:06 2001
@@ -1,18 +1,22 @@
 #ifndef _I386_CURRENT_H
 #define _I386_CURRENT_H
 
-struct task_struct;
+#include <linux/per_cpu.h>
 
-static inline struct task_struct * get_current(void)
+//static inline struct task_struct *get_current(void) __attribute__((pure));
+static inline struct task_struct *get_current(void)
 {
-	struct task_struct *tsk;
-	__asm__("movl %%cr2,%0;": "=r" (tsk));
-	return tsk;
+	return per_data(smp_processor_id())->curr;
 }
 
 /* for within NMI, do_page_fault, cpu_init */
 static inline struct task_struct * hard_get_current(void)
 {
+#if 0
+	int nr = hard_smp_processor_id();
+	nr = physical_apicid_to_cpu[nr];
+	return per_data(nr)->curr;
+#endif
 	struct task_struct **ptsk;
 	__asm__("andl %%esp,%0; ":"=r" (ptsk) : "0" (~8191UL));
 	return *ptsk;
@@ -20,9 +24,7 @@
 
 static inline void set_current(struct task_struct *tsk)
 {
-	__asm__("movl %0,%%cr2;"
-			: /* no output */
-			:"r" (tsk));
+	per_data(smp_processor_id())->curr = tsk;
 }
    
 /* Note: the implementation is hardcoded into arch/i386/lib/getuser.S */
Only in v2.4.13-ac8+tr.4/include/asm-i386: current_asm.h
diff -ur kernels/2.4/v2.4.13-ac8/include/asm-i386/desc.h v2.4.13-ac8+tr.4/include/asm-i386/desc.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/desc.h	Tue Nov  6 20:43:27 2001
+++ v2.4.13-ac8+tr.4/include/asm-i386/desc.h	Tue Nov  6 21:21:32 2001
@@ -68,40 +68,6 @@
 
 #define __load_LDT(n) __asm__ __volatile__("lldt %%ax"::"a" (__LDT(n)<<3))
 
-/*
- * This is the ldt that every process will get unless we need
- * something other than this.
- */
-extern struct desc_struct default_ldt[];
-extern void set_intr_gate(unsigned int irq, void * addr);
-extern void set_ldt_desc(unsigned int n, void *addr, unsigned int size);
-extern void set_tss_desc(unsigned int n, void *addr);
-
-static inline void clear_LDT(void)
-{
-	int cpu = smp_processor_id();
-	set_ldt_desc(cpu, &default_ldt[0], 5);
-	__load_LDT(cpu);
-}
-
-/*
- * load one particular LDT into the current CPU
- */
-static inline void load_LDT (struct mm_struct *mm)
-{
-	int cpu = smp_processor_id();
-	void *segments = mm->context.segments;
-	int count = LDT_ENTRIES;
-
-	if (!segments) {
-		segments = &default_ldt[0];
-		count = 5;
-	}
-		
-	set_ldt_desc(cpu, segments, count);
-	__load_LDT(cpu);
-}
-
 #endif /* !__ASSEMBLY__ */
 
 #endif
Only in v2.4.13-ac8+tr.4/include/asm-i386: descfn.h
diff -ur kernels/2.4/v2.4.13-ac8/include/asm-i386/mmu_context.h v2.4.13-ac8+tr.4/include/asm-i386/mmu_context.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/mmu_context.h	Tue Nov  6 21:23:24 2001
+++ v2.4.13-ac8+tr.4/include/asm-i386/mmu_context.h	Sat Nov 10 16:02:56 2001
@@ -5,6 +5,7 @@
 #include <asm/desc.h>
 #include <asm/atomic.h>
 #include <asm/pgalloc.h>
+#include <asm/descfn.h>
 
 /*
  * possibly do the LDT unload here?
diff -ur kernels/2.4/v2.4.13-ac8/include/asm-i386/smp.h v2.4.13-ac8+tr.4/include/asm-i386/smp.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/smp.h	Tue Nov  6 21:00:35 2001
+++ v2.4.13-ac8+tr.4/include/asm-i386/smp.h	Sat Nov 10 16:02:52 2001
@@ -8,6 +8,7 @@
 #include <linux/config.h>
 #include <linux/threads.h>
 #include <linux/ptrace.h>
+#include <asm/desc.h>
 #endif
 
 #ifdef CONFIG_X86_LOCAL_APIC
@@ -83,10 +84,10 @@
  * the real APIC ID <-> CPU # mapping.
  */
 #define MAX_APICID 256
-extern volatile int cpu_to_physical_apicid[NR_CPUS];
-extern volatile int physical_apicid_to_cpu[MAX_APICID];
-extern volatile int cpu_to_logical_apicid[NR_CPUS];
-extern volatile int logical_apicid_to_cpu[MAX_APICID];
+extern volatile int physical_apicid_to_cpu[];
+extern volatile int cpu_to_physical_apicid[];
+extern volatile int cpu_to_logical_apicid[];
+extern volatile int logical_apicid_to_cpu[];
 
 /*
  * General functions that each host system must provide.
@@ -101,7 +102,20 @@
  * so this is correct in the x86 case.
  */
 
-#define smp_processor_id() (current->processor)
+static unsigned get_TR(void) __attribute__ ((pure));
+static unsigned get_TR(void)
+{
+	unsigned tr;
+	/* The PAIN!  The HORROR!
+	 * Technically this is wrong, wrong, wrong, but 
+	 * gas doesn't know about strl.  *sigh*  Please 
+	 * flog them with a wet noodle repeatedly.  -ben
+	 */
+	__asm__ __volatile__("str %w0" : "=r" (tr));
+	return tr;
+}
+
+#define smp_processor_id()	( ((get_TR() >> 3) - __FIRST_TSS_ENTRY) >> 2 )
 
 static __inline int hard_smp_processor_id(void)
 {
diff -ur kernels/2.4/v2.4.13-ac8/include/asm-i386/smpboot.h v2.4.13-ac8+tr.4/include/asm-i386/smpboot.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/smpboot.h	Fri Nov  9 23:55:07 2001
+++ v2.4.13-ac8+tr.4/include/asm-i386/smpboot.h	Sat Nov 10 15:57:58 2001
@@ -36,21 +36,21 @@
  * Mappings between logical cpu number and logical / physical apicid
  * The first four macros are trivial, but it keeps the abstraction consistent
  */
-extern volatile int logical_apicid_2_cpu[];
-extern volatile int cpu_2_logical_apicid[];
-extern volatile int physical_apicid_2_cpu[];
-extern volatile int cpu_2_physical_apicid[];
+extern volatile int logical_apicid_to_cpu[];
+extern volatile int cpu_to_logical_apicid[];
+extern volatile int physical_apicid_to_cpu[];
+extern volatile int cpu_to_physical_apicid[];
 
-#define logical_apicid_to_cpu(apicid) logical_apicid_2_cpu[apicid]
-#define cpu_to_logical_apicid(cpu) cpu_2_logical_apicid[cpu]
-#define physical_apicid_to_cpu(apicid) physical_apicid_2_cpu[apicid]
-#define cpu_to_physical_apicid(cpu) cpu_2_physical_apicid[cpu]
+#define logical_apicid_to_cpu(apicid) logical_apicid_to_cpu[apicid]
+#define cpu_to_logical_apicid(cpu) cpu_to_logical_apicid[cpu]
+#define physical_apicid_to_cpu(apicid) physical_apicid_to_cpu[apicid]
+#define cpu_to_physical_apicid(cpu) cpu_to_physical_apicid[cpu]
 #ifdef CONFIG_MULTIQUAD			/* use logical IDs to bootstrap */
-#define boot_apicid_to_cpu(apicid) logical_apicid_2_cpu[apicid]
-#define cpu_to_boot_apicid(cpu) cpu_2_logical_apicid[cpu]
+#define boot_apicid_to_cpu(apicid) logical_apicid_to_cpu[apicid]
+#define cpu_to_boot_apicid(cpu) cpu_to_logical_apicid[cpu]
 #else /* !CONFIG_MULTIQUAD */		/* use physical IDs to bootstrap */
-#define boot_apicid_to_cpu(apicid) physical_apicid_2_cpu[apicid]
-#define cpu_to_boot_apicid(cpu) cpu_2_physical_apicid[cpu]
+#define boot_apicid_to_cpu(apicid) physical_apicid_to_cpu[apicid]
+#define cpu_to_boot_apicid(cpu) cpu_to_physical_apicid[cpu]
 #endif /* CONFIG_MULTIQUAD */
 
 
diff -ur kernels/2.4/v2.4.13-ac8/include/asm-i386/uaccess.h v2.4.13-ac8+tr.4/include/asm-i386/uaccess.h
--- kernels/2.4/v2.4.13-ac8/include/asm-i386/uaccess.h	Wed Nov  7 18:09:12 2001
+++ v2.4.13-ac8+tr.4/include/asm-i386/uaccess.h	Sat Nov 10 16:32:09 2001
@@ -109,7 +109,7 @@
 #define __get_user_x(size,ret,x,ptr) \
 	__asm__ __volatile__("call __get_user_" #size \
 		:"=a" (ret),"=d" (x) \
-		:"0" (ptr))
+		:"0" (ptr), "1" (current))
 
 /* Careful: we have to cast the result to the type of the pointer for sign reasons */
 #define get_user(x,ptr)							\
Only in v2.4.13-ac8+tr.4/include/linux: per_cpu.h
diff -ur kernels/2.4/v2.4.13-ac8/init/main.c v2.4.13-ac8+tr.4/init/main.c
--- kernels/2.4/v2.4.13-ac8/init/main.c	Tue Nov  6 20:43:28 2001
+++ v2.4.13-ac8+tr.4/init/main.c	Sat Nov 10 13:11:06 2001
@@ -635,7 +635,6 @@
  * Interrupts are still disabled. Do necessary setups, then
  * enable them
  */
-	lock_kernel();
 	printk(linux_banner);
 	setup_arch(&command_line);
 	printk("Kernel command line: %s\n", saved_command_line);
@@ -646,6 +645,13 @@
 	softirq_init();
 	time_init();
 
+	/* At the very least, this has to come after trap_init as x86
+	 * needs to perform CPU setup before current is valid.  This 
+	 * should be okay as we're still running with interrupts disabled 
+	 * and no other CPUs are up yet.  -ben
+	 */
+	lock_kernel();
+
 	/*
 	 * HACK ALERT! This is early. We're enabling the console before
 	 * we've done PCI setups etc, and console_init() must be aware of
diff -ur kernels/2.4/v2.4.13-ac8/kernel/ksyms.c v2.4.13-ac8+tr.4/kernel/ksyms.c
--- kernels/2.4/v2.4.13-ac8/kernel/ksyms.c	Tue Nov  6 20:43:28 2001
+++ v2.4.13-ac8+tr.4/kernel/ksyms.c	Sat Nov 10 16:57:06 2001
@@ -447,6 +447,7 @@
 #endif
 EXPORT_SYMBOL(kstat);
 EXPORT_SYMBOL(nr_running);
+EXPORT_SYMBOL(aligned_data);
 
 /* misc */
 EXPORT_SYMBOL(panic);
diff -ur kernels/2.4/v2.4.13-ac8/kernel/sched.c v2.4.13-ac8+tr.4/kernel/sched.c
--- kernels/2.4/v2.4.13-ac8/kernel/sched.c	Tue Nov  6 20:43:28 2001
+++ v2.4.13-ac8+tr.4/kernel/sched.c	Sat Nov 10 16:29:58 2001
@@ -28,6 +28,7 @@
 #include <linux/kernel_stat.h>
 #include <linux/completion.h>
 #include <linux/prefetch.h>
+#include <linux/per_cpu.h>
 
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
@@ -97,16 +98,10 @@
  * We align per-CPU scheduling data on cacheline boundaries,
  * to prevent cacheline ping-pong.
  */
-static union {
-	struct schedule_data {
-		struct task_struct * curr;
-		cycles_t last_schedule;
-	} schedule_data;
-	char __pad [SMP_CACHE_BYTES];
-} aligned_data [NR_CPUS] __cacheline_aligned = { {{&init_task,0}}};
+union aligned_data aligned_data[NR_CPUS] __cacheline_aligned;
 
-#define cpu_curr(cpu) aligned_data[(cpu)].schedule_data.curr
-#define last_schedule(cpu) aligned_data[(cpu)].schedule_data.last_schedule
+#define cpu_curr(cpu)		per_data(cpu)->curr
+#define last_schedule(cpu)	per_data(cpu)->last_schedule
 
 struct kernel_stat kstat;
 extern struct task_struct *child_reaper;
@@ -532,7 +527,7 @@
  */
 asmlinkage void schedule(void)
 {
-	struct schedule_data * sched_data;
+	struct per_cpu_data * sched_data;
 	struct task_struct *prev, *next, *p;
 	struct list_head *tmp;
 	int this_cpu, c;
@@ -543,7 +538,7 @@
 	if (!current->active_mm) BUG();
 need_resched_back:
 	prev = current;
-	this_cpu = prev->processor;
+	this_cpu = smp_processor_id();	/* This better than current->processor on up */
 
 	if (in_interrupt())
 		goto scheduling_in_interrupt;
@@ -554,7 +549,7 @@
 	 * 'sched_data' is protected by the fact that we can run
 	 * only one process per CPU.
 	 */
-	sched_data = & aligned_data[this_cpu].schedule_data;
+	sched_data = per_data(this_cpu);
 
 	spin_lock_irq(&runqueue_lock);
 
@@ -1057,7 +1052,7 @@
 	// Subtract non-idle processes running on other CPUs.
 	for (i = 0; i < smp_num_cpus; i++) {
 		int cpu = cpu_logical_map(i);
-		if (aligned_data[cpu].schedule_data.curr != idle_task(cpu))
+		if (per_data(cpu)->curr != idle_task(cpu))
 			nr_pending--;
 	}
 #else
@@ -1309,17 +1304,18 @@
 
 void __init init_idle(void)
 {
-	struct schedule_data * sched_data;
-	sched_data = &aligned_data[smp_processor_id()].schedule_data;
+	struct per_cpu_data * sched_data;
+	int cpu = smp_processor_id();
+	sched_data = per_data(cpu);
 
 	if (current != &init_task && task_on_runqueue(current)) {
 		printk("UGH! (%d:%d) was on the runqueue, removing.\n",
-			smp_processor_id(), current->pid);
+			cpu, current->pid);
 		del_from_runqueue(current);
 	}
 	sched_data->curr = current;
 	sched_data->last_schedule = get_cycles();
-	clear_bit(current->processor, &wait_init_idle);
+	clear_bit(cpu, &wait_init_idle);
 }
 
 extern void init_timervecs (void);
@@ -1334,6 +1330,7 @@
 	int nr;
 
 	init_task.processor = cpu;
+	set_current(&init_task);
 
 	for(nr = 0; nr < PIDHASH_SZ; nr++)
 		pidhash[nr] = NULL;

Re: [RFT] final cur of tr based current for -ac8

[Keith Owens]

On Sat, 10 Nov 2001 17:33:31 -0500, 
Benjamin LaHaise <bcrl@redhat.com> wrote:
>diff -ur kernels/2.4/v2.4.13-ac8/arch/i386/kernel/nmi.c v2.4.13-ac8+tr.4/arch/i386/kernel/nmi.c
>--- kernels/2.4/v2.4.13-ac8/arch/i386/kernel/nmi.c	Tue Nov  6 20:43:22 2001
>+++ v2.4.13-ac8+tr.4/arch/i386/kernel/nmi.c	Sat Nov 10 14:00:33 2001
>@@ -264,7 +264,7 @@
> 	/*
> 	 * NMI can interrupt page faults, use hard_get_current.
> 	 */
>-	int sum, cpu = hard_get_current()->processor;
>+	int sum, cpu = hard_smp_processor_id();
> 
> 	sum = apic_timer_irqs[cpu];

I am still unhappy with that NMI code.  The NMI handler can use generic
code including printk, the generic code will use the standard
get_current.  Why does nmi.c not do set_current(hard_get_current());

Re: [RFT] final cur of tr based current for -ac8

[Benjamin LaHaise]

On Sun, Nov 11, 2001 at 09:54:48AM +1100, Keith Owens wrote:
> I am still unhappy with that NMI code.  The NMI handler can use generic
> code including printk, the generic code will use the standard
> get_current.  Why does nmi.c not do set_current(hard_get_current());

It can in the current version, but that's generally wrong.  The current 
dependancy is that hard_get_current() only really needs to be used during 
early boot before the TR register is set.  Once that's done, the code can 
use smp_processor_id() anywhere.

		-ben
-- 
Fish.

Re: [RFT] final cur of tr based current for -ac8

[John Levon]

On Sat, Nov 10, 2001 at 05:33:31PM -0500, Benjamin LaHaise wrote:

> Thanks...  I seem to have blotched the SMP side of things (again) which this 
> might fix (including the symbol export from you).  Also, Michael Barabanov 
> came up with a patch using the same trick, although I haven't seen it.

You forgot -N option of diff :

Only in v2.4.13-ac8+tr.4/include/linux: per_cpu.h

Testing on my SMP box would be a bit awkward (not set up ppp/serial, so would have
to transfer patches from 2.4.5 by floppy ;) but if you need an SMP test done,
just shout.

On the UP box, the previous patch has now survived several hours under very heavy
NMI load, so I assume it's good.

thanks
john

-- 
"I know I believe in nothing but it is my nothing"
	- Manic Street Preachers

Re: [RFT] final cur of tr based current for -ac8

[Mike Galbraith]

On Sat, 10 Nov 2001, Benjamin LaHaise wrote:

> +static unsigned get_TR(void)
> +{
> +	unsigned tr;
> +	/* The PAIN!  The HORROR!
> +	 * Technically this is wrong, wrong, wrong, but
> +	 * gas doesn't know about strl.  *sigh*  Please
> +	 * flog them with a wet noodle repeatedly.  -ben
> +	 */
> +	__asm__ __volatile__("str %w0" : "=r" (tr));
> +	return tr;
> +}

The below seems to make flogging noises, but is likely too soggy.

	-Mike

diff -urN binutils-2.11.2/include/opcode/i386.h binutils-2.11.2.twiddle/include/opcode/i386.h
--- binutils-2.11.2/include/opcode/i386.h	Sat May 12 12:09:19 2001
+++ binutils-2.11.2.noodle/include/opcode/i386.h	Sun Nov 11 09:46:13 2001
@@ -555,7 +555,8 @@
 {"sidt",   1, 0x0f01, 1, Cpu286, wlq_Suf|Modrm,		{ WordMem, 0, 0} },
 {"sldt",   1, 0x0f00, 0, Cpu286, wlq_Suf|Modrm,		{ WordReg|WordMem, 0, 0} },
 {"smsw",   1, 0x0f01, 4, Cpu286, wlq_Suf|Modrm,		{ WordReg|WordMem, 0, 0} },
-{"str",	   1, 0x0f00, 1, Cpu286, w_Suf|Modrm|IgnoreSize,{ Reg16|ShortMem, 0, 0} },
+{"str",    1, 0x0f00, 1, Cpu286, w_Suf|Modrm|IgnoreSize,{ Reg16|ShortMem, 0, 0} },
+{"str",	  1, 0x0f00, 1, Cpu386, wlq_Suf|Modrm,    { WordReg|WordMem, 0, 0} },

 {"verr",   1, 0x0f00, 4, Cpu286, w_Suf|Modrm|IgnoreSize,{ Reg16|ShortMem, 0, 0} },
 {"verw",   1, 0x0f00, 5, Cpu286, w_Suf|Modrm|IgnoreSize,{ Reg16|ShortMem, 0, 0} },
diff -urN binutils-2.11.2/opcodes/i386-dis.c binutils-2.11.2.twiddle/opcodes/i386-dis.c
--- binutils-2.11.2/opcodes/i386-dis.c	Mon Jun 11 12:05:17 2001
+++ binutils-2.11.2.noodle/opcodes/i386-dis.c	Sun Nov 11 08:56:45 2001
@@ -2466,7 +2466,7 @@
   /* GRP6 */
   {
     { "sldt",	Ew, XX, XX },
-    { "str",	Ew, XX, XX },
+    { "strQ",	Ev, XX, XX },
     { "lldt",	Ew, XX, XX },
     { "ltr",	Ew, XX, XX },
     { "verr",	Ew, XX, XX },

-----------------------------------------------------------------------
static unsigned get_TR(int tryit)
{
       unsigned tr;
       if (tryit)
       	__asm__ __volatile__("strl %0" : "=r" (tr));
       else
       	__asm__ __volatile__("str %w0" : "=r" (tr));
       return tr;
}

08048400 <get_TR>:
 8048400:	55                   	push   %ebp
 8048401:	89 e5                	mov    %esp,%ebp
 8048403:	83 7d 08 00          	cmpl   $0x0,0x8(%ebp)
 8048407:	74 07                	je     8048410 <get_TR+0x10>
 8048409:	0f 00 c8             	str    %eax
 804840c:	eb 06                	jmp    8048414 <get_TR+0x14>
 804840e:	89 f6                	mov    %esi,%esi
 8048410:	66 0f 00 c8          	str    %ax
 8048414:	89 ec                	mov    %ebp,%esp
 8048416:	5d                   	pop    %ebp
 8048417:	c3                   	ret

Re: [RFT] final cur of tr based current for -ac8

[Benjamin LaHaise]

On Sun, Nov 11, 2001 at 11:58:30AM +0100, Mike Galbraith wrote:
> The below seems to make flogging noises, but is likely too soggy.

Erk, the behaviour of str with your patch isn't quite compatible 
enough for a smooth transition.  What is really needed is to have 
"str" error out or generate the existing strl with a huge warning 
about unspecified type.  Either way the kernel has to work with 
both old and new tools for a brief period of time.

		-ben

Re: [RFT] final cur of tr based current for -ac8

[H. Peter Anvin]

Followup to:  <20011111190114.A31746@redhat.com>
By author:    Benjamin LaHaise <bcrl@redhat.com>
In newsgroup: linux.dev.kernel
>
> On Sun, Nov 11, 2001 at 11:58:30AM +0100, Mike Galbraith wrote:
> > The below seems to make flogging noises, but is likely too soggy.
> 
> Erk, the behaviour of str with your patch isn't quite compatible 
> enough for a smooth transition.  What is really needed is to have 
> "str" error out or generate the existing strl with a huge warning 
> about unspecified type.  Either way the kernel has to work with 
> both old and new tools for a brief period of time.
> 

The current behaviour is a bug, plain and simple.  The only way to
make backwards-compatible behaviour is to make "strl %eax" and "strw
%ax" behave properly while "str %ax" really does an "strl %eax" (the
current, broken, behaviour.)

	-hpa

-- 
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."
http://www.zytor.com/~hpa/puzzle.txt	<amsp@zytor.com>