* Copyright 1999, 2000, 2001, 2008 Bernie Innocenti <bernie@codewiz.org>
* -->
*
- * \brief Bertos Kernel core (Process scheduler).
+ * \brief BeRTOS Kernel core (Process scheduler).
*
* \version $Id$
* \author Bernie Innocenti <bernie@codewiz.org>
*
* $WIZ$ module_name = "kernel"
* $WIZ$ module_configuration = "bertos/cfg/cfg_proc.h"
+ * $WIZ$ module_depends = "switch_ctx", "coop"
+ * $WIZ$ module_supports = "not atmega103"
*/
#ifndef KERN_PROC_H
#define KERN_PROC_H
#include "cfg/cfg_proc.h"
+#include "cfg/cfg_signal.h"
#include "cfg/cfg_monitor.h"
+#include <struct/list.h> // Node, PriNode
+
#include <cfg/compiler.h>
#if CONFIG_KERN_PREEMPT
#include <cpu/frame.h> // CPU_SAVED_REGS_CNT
/*
- * Forward declaration. The definition of struct Process is private to the
- * scheduler and hidden in proc_p.h.
+ * WARNING: struct Process is considered private, so its definition can change any time
+ * without notice. DO NOT RELY on any field defined here, use only the interface
+ * functions below.
+ *
+ * You have been warned.
*/
-struct Process;
+typedef struct Process
+{
+#if CONFIG_KERN_PRI
+ PriNode link; /**< Link Process into scheduler lists */
+#else
+ Node link; /**< Link Process into scheduler lists */
+#endif
+ cpu_stack_t *stack; /**< Per-process SP */
+ iptr_t user_data; /**< Custom data passed to the process */
+
+#if CONFIG_KERN_SIGNALS
+ sigmask_t sig_wait; /**< Signals the process is waiting for */
+ sigmask_t sig_recv; /**< Received signals */
+#endif
+
+#if CONFIG_KERN_HEAP
+ uint16_t flags; /**< Flags */
+#endif
+
+#if CONFIG_KERN_HEAP | CONFIG_KERN_MONITOR | (ARCH & ARCH_EMUL)
+ cpu_stack_t *stack_base; /**< Base of process stack */
+ size_t stack_size; /**< Size of process stack */
+#endif
+
+#if CONFIG_KERN_PREEMPT
+ ucontext_t context;
+#endif
+#if CONFIG_KERN_MONITOR
+ struct ProcMonitor
+ {
+ Node link;
+ const char *name;
+ } monitor;
+#endif
+
+} Process;
+
+/**
+ * Initialize the process subsystem (kernel).
+ * It must be called before using any process related function.
+ */
void proc_init(void);
+
struct Process *proc_new_with_name(const char *name, void (*entry)(void), iptr_t data, size_t stacksize, cpu_stack_t *stack);
#if !CONFIG_KERN_MONITOR
+ /**
+ * Create a new named process and schedules it for execution.
+ *
+ * When defining the stacksize take into account that you may want at least:
+ * \li save all the registers for each nested function call;
+ * \li have memory for the struct Process, which is positioned at the bottom
+ * of the stack;
+ * \li have some memory for temporary variables inside called functions.
+ *
+ * The value given by KERN_MINSTACKSIZE is rather safe to use in the first place.
+ *
+ * \param entry Function that the process will execute.
+ * \param data Pointer to user data.
+ * \param size Length of the stack.
+ * \param stack Pointer to the memory area to be used as a stack.
+ *
+ * \return Process structure of new created process
+ * if successful, NULL otherwise.
+ */
#define proc_new(entry,data,size,stack) proc_new_with_name(NULL,(entry),(data),(size),(stack))
#else
#define proc_new(entry,data,size,stack) proc_new_with_name(#entry,(entry),(data),(size),(stack))
#endif
+/**
+ * Terminate the execution of the current process.
+ */
void proc_exit(void);
+
+/**
+ * Co-operative context switch.
+ *
+ * The process that calls this function will release the CPU before its cpu quantum
+ * expires, the scheduler will run to select the next process that will take control
+ * of the processor.
+ * \note This function is available only if CONFIG_KERN is enabled
+ * \sa cpu_relax(), which is the recommended method to release the cpu.
+ */
void proc_yield(void);
+
void proc_rename(struct Process *proc, const char *name);
const char *proc_name(struct Process *proc);
const char *proc_currentName(void);
+
+/**
+ * Return a pointer to the user data of the current process.
+ *
+ * To obtain user data, just call this function inside the process. Remember to cast
+ * the returned pointer to the correct type.
+ * \return Pointer to the user data of the current process.
+ */
iptr_t proc_currentUserData(void);
int proc_testSetup(void);
proc_permit(); \
} while(0)
-#ifndef CONFIG_KERN_MINSTACKSIZE
+/**
+ * Default stack size for each thread, in bytes.
+ *
+ * The goal here is to allow a minimal task to save all of its
+ * registers twice, plus push a maximum of 32 variables on the
+ * stack. We add also struct Process size since we save it into the process'
+ * stack.
+ *
+ * The actual size computed by the default formula greatly depends on what
+ * options are active and on the architecture.
+ *
+ * Note that on most 16bit architectures, interrupts will also
+ * run on the stack of the currently running process. Nested
+ * interrupts will greatly increases the amount of stack space
+ * required per process. Use irqmanager to minimize stack
+ * usage.
+ */
- #if (ARCH & ARCH_EMUL)
- /* We need a large stack because system libraries are bloated */
- #define CONFIG_KERN_MINSTACKSIZE 65536
- #else
- /**
- * Default stack size for each thread, in bytes.
- *
- * The goal here is to allow a minimal task to save all of its
- * registers twice, plus push a maximum of 32 variables on the
- * stack.
- *
- * The actual size computed by the default formula is:
- * AVR: 102
- * i386: 156
- * ARM: 164
- * x86_64: 184
- *
- * Note that on most 16bit architectures, interrupts will also
- * run on the stack of the currently running process. Nested
- * interrupts will greatly increases the amount of stack space
- * required per process. Use irqmanager to minimize stack
- * usage.
- */
- #define CONFIG_KERN_MINSTACKSIZE \
- (CPU_SAVED_REGS_CNT * 2 * sizeof(cpu_stack_t) \
- + 48 * sizeof(int))
- #endif
+#if (ARCH & ARCH_EMUL)
+ /* We need a large stack because system libraries are bloated */
+ #define KERN_MINSTACKSIZE 65536
+#else
+ #define KERN_MINSTACKSIZE \
+ (sizeof(Process) + CPU_SAVED_REGS_CNT * 2 * sizeof(cpu_stack_t) \
+ + 32 * sizeof(int))
+#endif
+
+#ifndef CONFIG_KERN_MINSTACKSIZE
+ /* For backward compatibility */
+ #define CONFIG_KERN_MINSTACKSIZE KERN_MINSTACKSIZE
+#else
+ #warning FIXME: This macro is deprecated, use KERN_MINSTACKSIZE instead
#endif
+/**
+ * Utility macro to allocate a stack of size \a size.
+ *
+ * This macro define a static stack for one process and do
+ * check if given stack size is enough to run process.
+ * \note If you plan to use kprintf() and similar functions, you will need
+ * at least KERN_MINSTACKSIZE * 2 bytes.
+ *
+ * \param name Variable name for the stack.
+ * \param size Stack size in bytes. It must be at least KERN_MINSTACKSIZE.
+ */
+#define PROC_DEFINE_STACK(name, size) \
+ STATIC_ASSERT((size) >= KERN_MINSTACKSIZE); \
+ cpu_stack_t name[(size) / sizeof(cpu_stack_t)];
+
/* Memory fill codes to help debugging */
#if CONFIG_KERN_MONITOR
#include <cpu/types.h>