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-rw-r--r--arch/um/Kconfig.um30
-rw-r--r--arch/um/include/asm/processor-generic.h8
-rw-r--r--arch/um/include/asm/smp.h26
-rw-r--r--arch/um/kernel/Makefile2
-rw-r--r--arch/um/kernel/irq.c3
-rw-r--r--arch/um/kernel/process.c11
-rw-r--r--arch/um/kernel/skas/process.c4
-rw-r--r--arch/um/kernel/smp.c238
-rw-r--r--arch/um/kernel/um_arch.c35
-rw-r--r--arch/x86/um/asm/barrier.h11
10 files changed, 2 insertions, 366 deletions
diff --git a/arch/um/Kconfig.um b/arch/um/Kconfig.um
index a7520c90f62d..ff86fbedc2fc 100644
--- a/arch/um/Kconfig.um
+++ b/arch/um/Kconfig.um
@@ -95,36 +95,6 @@ config MAGIC_SYSRQ
The keys are documented in <file:Documentation/sysrq.txt>. Don't say Y
unless you really know what this hack does.
-config SMP
- bool "Symmetric multi-processing support"
- default n
- depends on BROKEN
- help
- This option enables UML SMP support.
- It is NOT related to having a real SMP box. Not directly, at least.
-
- UML implements virtual SMP by allowing as many processes to run
- simultaneously on the host as there are virtual processors configured.
-
- Obviously, if the host is a uniprocessor, those processes will
- timeshare, but, inside UML, will appear to be running simultaneously.
- If the host is a multiprocessor, then UML processes may run
- simultaneously, depending on the host scheduler.
-
- This, however, is supported only in TT mode. So, if you use the SKAS
- patch on your host, switching to TT mode and enabling SMP usually
- gives you worse performances.
- Also, since the support for SMP has been under-developed, there could
- be some bugs being exposed by enabling SMP.
-
- If you don't know what to do, say N.
-
-config NR_CPUS
- int "Maximum number of CPUs (2-32)"
- range 2 32
- depends on SMP
- default "32"
-
config HIGHMEM
bool "Highmem support"
depends on !64BIT && BROKEN
diff --git a/arch/um/include/asm/processor-generic.h b/arch/um/include/asm/processor-generic.h
index cbc5edd5a901..2d1e0dd5bb0b 100644
--- a/arch/um/include/asm/processor-generic.h
+++ b/arch/um/include/asm/processor-generic.h
@@ -98,16 +98,8 @@ struct cpuinfo_um {
extern struct cpuinfo_um boot_cpu_data;
-#define my_cpu_data cpu_data[smp_processor_id()]
-
-#ifdef CONFIG_SMP
-extern struct cpuinfo_um cpu_data[];
-#define current_cpu_data cpu_data[smp_processor_id()]
-#else
#define cpu_data (&boot_cpu_data)
#define current_cpu_data boot_cpu_data
-#endif
-
#define KSTK_REG(tsk, reg) get_thread_reg(reg, &tsk->thread.switch_buf)
extern unsigned long get_wchan(struct task_struct *p);
diff --git a/arch/um/include/asm/smp.h b/arch/um/include/asm/smp.h
index e4507938d8cf..9c3be355ed01 100644
--- a/arch/um/include/asm/smp.h
+++ b/arch/um/include/asm/smp.h
@@ -1,32 +1,6 @@
#ifndef __UM_SMP_H
#define __UM_SMP_H
-#ifdef CONFIG_SMP
-
-#include <linux/bitops.h>
-#include <asm/current.h>
-#include <linux/cpumask.h>
-
-#define raw_smp_processor_id() (current_thread->cpu)
-
-#define cpu_logical_map(n) (n)
-#define cpu_number_map(n) (n)
-extern int hard_smp_processor_id(void);
-#define NO_PROC_ID -1
-
-extern int ncpus;
-
-
-static inline void smp_cpus_done(unsigned int maxcpus)
-{
-}
-
-extern struct task_struct *idle_threads[NR_CPUS];
-
-#else
-
#define hard_smp_processor_id() 0
#endif
-
-#endif
diff --git a/arch/um/kernel/Makefile b/arch/um/kernel/Makefile
index 2d840a070c8b..b7e31e5a8c0c 100644
--- a/arch/um/kernel/Makefile
+++ b/arch/um/kernel/Makefile
@@ -12,7 +12,7 @@ clean-files :=
obj-y = config.o exec.o exitcode.o irq.o ksyms.o mem.o \
physmem.o process.o ptrace.o reboot.o sigio.o \
- signal.o smp.o syscall.o sysrq.o time.o tlb.o trap.o \
+ signal.o syscall.o sysrq.o time.o tlb.o trap.o \
um_arch.o umid.o maccess.o skas/
obj-$(CONFIG_BLK_DEV_INITRD) += initrd.o
diff --git a/arch/um/kernel/irq.c b/arch/um/kernel/irq.c
index 1d8505b1e290..23cb9350d47e 100644
--- a/arch/um/kernel/irq.c
+++ b/arch/um/kernel/irq.c
@@ -35,9 +35,6 @@ void sigio_handler(int sig, struct siginfo *unused_si, struct uml_pt_regs *regs)
struct irq_fd *irq_fd;
int n;
- if (smp_sigio_handler())
- return;
-
while (1) {
n = os_waiting_for_events(active_fds);
if (n <= 0) {
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index f17bca8ed2ce..68b9119841cd 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -259,17 +259,6 @@ int strlen_user_proc(char __user *str)
return strlen_user(str);
}
-int smp_sigio_handler(void)
-{
-#ifdef CONFIG_SMP
- int cpu = current_thread_info()->cpu;
- IPI_handler(cpu);
- if (cpu != 0)
- return 1;
-#endif
- return 0;
-}
-
int cpu(void)
{
return current_thread_info()->cpu;
diff --git a/arch/um/kernel/skas/process.c b/arch/um/kernel/skas/process.c
index 082955d694f3..527fa5881915 100644
--- a/arch/um/kernel/skas/process.c
+++ b/arch/um/kernel/skas/process.c
@@ -21,9 +21,7 @@ static int __init start_kernel_proc(void *unused)
cpu_tasks[0].pid = pid;
cpu_tasks[0].task = current;
-#ifdef CONFIG_SMP
- init_cpu_online(get_cpu_mask(0));
-#endif
+
start_kernel();
return 0;
}
diff --git a/arch/um/kernel/smp.c b/arch/um/kernel/smp.c
deleted file mode 100644
index 5c8c3ea7db7b..000000000000
--- a/arch/um/kernel/smp.c
+++ /dev/null
@@ -1,238 +0,0 @@
-/*
- * Copyright (C) 2000 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
- * Licensed under the GPL
- */
-
-#include <linux/percpu.h>
-#include <asm/pgalloc.h>
-#include <asm/tlb.h>
-
-#ifdef CONFIG_SMP
-
-#include <linux/sched.h>
-#include <linux/module.h>
-#include <linux/threads.h>
-#include <linux/interrupt.h>
-#include <linux/err.h>
-#include <linux/hardirq.h>
-#include <asm/smp.h>
-#include <asm/processor.h>
-#include <asm/spinlock.h>
-#include <kern.h>
-#include <irq_user.h>
-#include <os.h>
-
-/* Per CPU bogomips and other parameters
- * The only piece used here is the ipi pipe, which is set before SMP is
- * started and never changed.
- */
-struct cpuinfo_um cpu_data[NR_CPUS];
-
-/* A statistic, can be a little off */
-int num_reschedules_sent = 0;
-
-/* Not changed after boot */
-struct task_struct *idle_threads[NR_CPUS];
-
-void smp_send_reschedule(int cpu)
-{
- os_write_file(cpu_data[cpu].ipi_pipe[1], "R", 1);
- num_reschedules_sent++;
-}
-
-void smp_send_stop(void)
-{
- int i;
-
- printk(KERN_INFO "Stopping all CPUs...");
- for (i = 0; i < num_online_cpus(); i++) {
- if (i == current_thread->cpu)
- continue;
- os_write_file(cpu_data[i].ipi_pipe[1], "S", 1);
- }
- printk(KERN_CONT "done\n");
-}
-
-static cpumask_t smp_commenced_mask = CPU_MASK_NONE;
-static cpumask_t cpu_callin_map = CPU_MASK_NONE;
-
-static int idle_proc(void *cpup)
-{
- int cpu = (int) cpup, err;
-
- err = os_pipe(cpu_data[cpu].ipi_pipe, 1, 1);
- if (err < 0)
- panic("CPU#%d failed to create IPI pipe, err = %d", cpu, -err);
-
- os_set_fd_async(cpu_data[cpu].ipi_pipe[0]);
-
- wmb();
- if (cpu_test_and_set(cpu, cpu_callin_map)) {
- printk(KERN_ERR "huh, CPU#%d already present??\n", cpu);
- BUG();
- }
-
- while (!cpu_isset(cpu, smp_commenced_mask))
- cpu_relax();
-
- notify_cpu_starting(cpu);
- set_cpu_online(cpu, true);
- default_idle();
- return 0;
-}
-
-static struct task_struct *idle_thread(int cpu)
-{
- struct task_struct *new_task;
-
- current->thread.request.u.thread.proc = idle_proc;
- current->thread.request.u.thread.arg = (void *) cpu;
- new_task = fork_idle(cpu);
- if (IS_ERR(new_task))
- panic("copy_process failed in idle_thread, error = %ld",
- PTR_ERR(new_task));
-
- cpu_tasks[cpu] = ((struct cpu_task)
- { .pid = new_task->thread.mode.tt.extern_pid,
- .task = new_task } );
- idle_threads[cpu] = new_task;
- panic("skas mode doesn't support SMP");
- return new_task;
-}
-
-void smp_prepare_cpus(unsigned int maxcpus)
-{
- struct task_struct *idle;
- unsigned long waittime;
- int err, cpu, me = smp_processor_id();
- int i;
-
- for (i = 0; i < ncpus; ++i)
- set_cpu_possible(i, true);
-
- set_cpu_online(me, true);
- cpu_set(me, cpu_callin_map);
-
- err = os_pipe(cpu_data[me].ipi_pipe, 1, 1);
- if (err < 0)
- panic("CPU#0 failed to create IPI pipe, errno = %d", -err);
-
- os_set_fd_async(cpu_data[me].ipi_pipe[0]);
-
- for (cpu = 1; cpu < ncpus; cpu++) {
- printk(KERN_INFO "Booting processor %d...\n", cpu);
-
- idle = idle_thread(cpu);
-
- init_idle(idle, cpu);
-
- waittime = 200000000;
- while (waittime-- && !cpu_isset(cpu, cpu_callin_map))
- cpu_relax();
-
- printk(KERN_INFO "%s\n",
- cpu_isset(cpu, cpu_calling_map) ? "done" : "failed");
- }
-}
-
-void smp_prepare_boot_cpu(void)
-{
- set_cpu_online(smp_processor_id(), true);
-}
-
-int __cpu_up(unsigned int cpu, struct task_struct *tidle)
-{
- cpu_set(cpu, smp_commenced_mask);
- while (!cpu_online(cpu))
- mb();
- return 0;
-}
-
-int setup_profiling_timer(unsigned int multiplier)
-{
- printk(KERN_INFO "setup_profiling_timer\n");
- return 0;
-}
-
-void smp_call_function_slave(int cpu);
-
-void IPI_handler(int cpu)
-{
- unsigned char c;
- int fd;
-
- fd = cpu_data[cpu].ipi_pipe[0];
- while (os_read_file(fd, &c, 1) == 1) {
- switch (c) {
- case 'C':
- smp_call_function_slave(cpu);
- break;
-
- case 'R':
- scheduler_ipi();
- break;
-
- case 'S':
- printk(KERN_INFO "CPU#%d stopping\n", cpu);
- while (1)
- pause();
- break;
-
- default:
- printk(KERN_ERR "CPU#%d received unknown IPI [%c]!\n",
- cpu, c);
- break;
- }
- }
-}
-
-int hard_smp_processor_id(void)
-{
- return pid_to_processor_id(os_getpid());
-}
-
-static DEFINE_SPINLOCK(call_lock);
-static atomic_t scf_started;
-static atomic_t scf_finished;
-static void (*func)(void *info);
-static void *info;
-
-void smp_call_function_slave(int cpu)
-{
- atomic_inc(&scf_started);
- (*func)(info);
- atomic_inc(&scf_finished);
-}
-
-int smp_call_function(void (*_func)(void *info), void *_info, int wait)
-{
- int cpus = num_online_cpus() - 1;
- int i;
-
- if (!cpus)
- return 0;
-
- /* Can deadlock when called with interrupts disabled */
- WARN_ON(irqs_disabled());
-
- spin_lock_bh(&call_lock);
- atomic_set(&scf_started, 0);
- atomic_set(&scf_finished, 0);
- func = _func;
- info = _info;
-
- for_each_online_cpu(i)
- os_write_file(cpu_data[i].ipi_pipe[1], "C", 1);
-
- while (atomic_read(&scf_started) != cpus)
- barrier();
-
- if (wait)
- while (atomic_read(&scf_finished) != cpus)
- barrier();
-
- spin_unlock_bh(&call_lock);
- return 0;
-}
-
-#endif
diff --git a/arch/um/kernel/um_arch.c b/arch/um/kernel/um_arch.c
index dbd5bda1f184..cd09285facf4 100644
--- a/arch/um/kernel/um_arch.c
+++ b/arch/um/kernel/um_arch.c
@@ -66,12 +66,6 @@ static int show_cpuinfo(struct seq_file *m, void *v)
{
int index = 0;
-#ifdef CONFIG_SMP
- index = (struct cpuinfo_um *) v - cpu_data;
- if (!cpu_online(index))
- return 0;
-#endif
-
seq_printf(m, "processor\t: %d\n", index);
seq_printf(m, "vendor_id\t: User Mode Linux\n");
seq_printf(m, "model name\t: UML\n");
@@ -168,23 +162,6 @@ __uml_setup("debug", no_skas_debug_setup,
" this flag is not needed to run gdb on UML in skas mode\n\n"
);
-#ifdef CONFIG_SMP
-static int __init uml_ncpus_setup(char *line, int *add)
-{
- if (!sscanf(line, "%d", &ncpus)) {
- printf("Couldn't parse [%s]\n", line);
- return -1;
- }
-
- return 0;
-}
-
-__uml_setup("ncpus=", uml_ncpus_setup,
-"ncpus=<# of desired CPUs>\n"
-" This tells an SMP kernel how many virtual processors to start.\n\n"
-);
-#endif
-
static int __init Usage(char *line, int *add)
{
const char **p;
@@ -380,15 +357,3 @@ void __init check_bugs(void)
void apply_alternatives(struct alt_instr *start, struct alt_instr *end)
{
}
-
-#ifdef CONFIG_SMP
-void alternatives_smp_module_add(struct module *mod, char *name,
- void *locks, void *locks_end,
- void *text, void *text_end)
-{
-}
-
-void alternatives_smp_module_del(struct module *mod)
-{
-}
-#endif
diff --git a/arch/x86/um/asm/barrier.h b/arch/x86/um/asm/barrier.h
index 2d7d9a1f5b53..aec75a5d8722 100644
--- a/arch/x86/um/asm/barrier.h
+++ b/arch/x86/um/asm/barrier.h
@@ -36,22 +36,11 @@
#endif /* CONFIG_X86_PPRO_FENCE */
#define dma_wmb() barrier()
-#ifdef CONFIG_SMP
-
-#define smp_mb() mb()
-#define smp_rmb() dma_rmb()
-#define smp_wmb() barrier()
-#define set_mb(var, value) do { (void)xchg(&var, value); } while (0)
-
-#else /* CONFIG_SMP */
-
#define smp_mb() barrier()
#define smp_rmb() barrier()
#define smp_wmb() barrier()
#define set_mb(var, value) do { var = value; barrier(); } while (0)
-#endif /* CONFIG_SMP */
-
#define read_barrier_depends() do { } while (0)
#define smp_read_barrier_depends() do { } while (0)