/* * thread.h - Thread and related operations definition. * * Author Ghassan Almaless (2008,2009,2010,2011,2012) * Alain Greiner (2016) * * Copyright (c) UPMC Sorbonne Universites * * This file is part of ALMOS-MKH. * * ALMOS-MKH is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by * the Free Software Foundation; version 2.0 of the License. * * ALMOS-MKH is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License * along with ALMOS-MKH; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA */ #ifndef _THREAD_H_ #define _THREAD_H_ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include /*************************************************************************************** * These macros are used to compose or decompose the global thread identifier (TRDID) * to or from cluster identifier / local thread index (CXY , LTID) **************************************************************************************/ #define LTID_FROM_TRDID( trdid ) (ltid_t)(trdid & 0x0000FFFF) #define CXY_FROM_TRDID( trdid ) (cxy_t)(trdid >> 16) #define TRDID( cxy , ltid ) (trdid_t)((cxy << 16) | ltid ) /*************************************************************************************** * This enum defines the thread types. **************************************************************************************/ typedef enum { THREAD_USER = 0, /*! user thread (pthread) */ THREAD_RPC = 1, /*! kernel thread executing pending RPCs */ THREAD_DEV = 2, /*! kernel thread executing I/O device commands */ THREAD_IDLE = 3, /*! kernel idle thread */ } thread_type_t; /*************************************************************************************** * This defines the thread flags bit-vector. **************************************************************************************/ #define THREAD_FLAG_DETACHED 0x0001 /*! This thread is detached from parent */ #define THREAD_FLAG_JOIN_DONE 0x0002 /*! Parent thread made a join request */ #define THREAD_FLAG_KILL_DONE 0x0004 /*! This thread received a kill request */ #define THREAD_FLAG_SCHED 0x0008 /*! Scheduling required for this thread */ #define THREAD_FLAG_REQ_ACK 0x0010 /*! Acknowledge required from scheduler */ #define THREAD_FLAG_REQ_DELETE 0x0020 /*! Destruction required from scheduler */ /*************************************************************************************** * This defines the thread blocking causes bit-vector. **************************************************************************************/ #define THREAD_BLOCKED_GLOBAL 0x0001 /*! thread deactivated / wait activation */ #define THREAD_BLOCKED_IO 0x0002 /*! thread wait IO operation completion */ #define THREAD_BLOCKED_MAPPER 0x0004 /*! thread wait mapper */ #define THREAD_BLOCKED_EXIT 0x0008 /*! thread blocked in join / wait exit */ #define THREAD_BLOCKED_JOIN 0x0010 /*! thread blocked in exit / wait join */ #define THREAD_BLOCKED_SEM 0x0020 /*! thread wait semaphore */ #define THREAD_BLOCKED_PAGE 0x0040 /*! thread wait page access */ #define THREAD_BLOCKED_IDLE 0x0080 /*! thread RPC wait RPC_FIFO non empty */ #define THREAD_BLOCKED_USERSYNC 0x0100 /*! thread wait (cond/mutex/barrier) */ #define THREAD_BLOCKED_RPC 0x0200 /*! thread wait RPC completion */ #define THREAD_BLOCKED_ISR 0x0400 /*! thread DEV wait ISR */ #define THREAD_BLOCKED_WAIT 0x0800 /*! thread wait child process termination */ /*************************************************************************************** * This structure defines thread instrumentation informations. **************************************************************************************/ typedef struct thread_info_s { uint32_t pgfault_nr; /*! cumulated number of page fault */ uint32_t sched_nr; /*! TODO ??? [AG] */ uint32_t u_err_nr; /*! TODO ??? [AG] */ uint32_t m_err_nr; /*! TODO ??? [AG] */ cycle_t last_cycle; /*! last cycle counter value (date) */ cycle_t usr_cycles; /*! user execution duration (cycles) */ cycle_t sys_cycles; /*! system execution duration (cycles) */ } thread_info_t; /*************************************************************************************** * This structure defines a thread descriptor. * It is used for both the user threads and the kernel threads. * In a process, a user thread is identified by a unique TRDID (thread identifier): * - The TRDID 16 LSB bits contain the LTID (Local Thread Index). * - The TRDID 16 MSB bits contain the CXY of cluster containing the thread. * The main thread LTID value is always 0. * The LTID is used to index the th_tbl[] array in the local process descriptor. * This TRDID is computed by the process_register_thread() function, when the user * thread is registered in the local copy of the process descriptor. * WARNING : Don't modify the first 4 fields order, as this order is used by the * hal_kentry assembly code for the TSAR architecture. **************************************************************************************/ #define THREAD_SIGNATURE 0xDEADBEEF typedef struct thread_s { void * cpu_context; /*! pointer on CPU context switch */ void * fpu_context; /*! pointer on FPU context switch */ void * uzone_current; /*! used by hal_do_syscall & hal_do_except */ void * uzone_previous; /*! used by hal_do_syscall & hal_do_except */ intptr_t k_stack_base; /*! kernel stack base address */ uint32_t k_stack_size; /*! kernel stack size (bytes) */ uint32_t trdid; /*! thread index (cxy.ltid) */ thread_type_t type; /*! thread type */ uint32_t quantum; /*! number of clock ticks given to thread */ uint32_t ticks_nr; /*! number of ticks used */ uint32_t time_last_check; /*! last cpu_time_stamp */ core_t * core; /*! pointer to the owner core */ process_t * process; /*! pointer on local process descriptor */ xptr_t parent; /*! extended pointer on parent thread */ remote_spinlock_t join_lock; /*! lock protecting the join/exit */ xptr_t join_xp; /*! joining/killer thread extended pointer */ uint32_t * ack_rsp_count; /*! pointer on acknowledge response counter */ intptr_t u_stack_base; /*! user stack base address */ uint32_t u_stack_size; /*! user stack size (bytes) */ void * entry_func; /*! pointer on entry function */ void * entry_args; /*! pointer on entry function arguments */ uint32_t main_argc; /*! main thread number of arguments */ char ** main_argv; /*! main thread array of strings arguments */ uint32_t flags; /*! bit vector of flags */ uint32_t blocked; /*! bit vector of blocking causes */ error_t errno; /*! errno value set by last system call */ uint32_t utls; /*! user thread local storage */ bool_t fork_user; /*! user defined placement for next fork() */ cxy_t fork_cxy; /*! target cluster for next fork() */ list_entry_t sched_list; /*! member of threads attached to same core */ chdev_t * chdev; /*! chdev pointer (for a DEV thread only) */ reg_t save_sr; /*! used by sched_yield() function */ ioc_command_t ioc_cmd; /*! IOC device generic command */ txt_command_t txt_cmd; /*! TXT device generic command */ nic_command_t nic_cmd; /*! NIC device generic command */ mmc_command_t mmc_cmd; /*! MMC device generic command */ dma_command_t dma_cmd; /*! DMA device generic command */ cxy_t rpc_client_cxy; /*! client cluster index (for a RPC thread) */ xlist_entry_t wait_list; /*! member of threads blocked on same cond */ list_entry_t locks_root; /*! root of list of locks taken */ xlist_entry_t xlocks_root; /*! root of xlist of remote locks taken */ uint32_t local_locks; /*! number of local locks owned by thread */ uint32_t remote_locks; /*! number of remote locks owned by thread */ thread_info_t info; /*! embedded thread_info_t */ uint32_t signature; /*! for kernel stack overflow detection */ } thread_t; /*************************************************************************************** * This macro returns a pointer on the calling thread from the core hardware register. **************************************************************************************/ #define CURRENT_THREAD (hal_get_current_thread()) /*************************************************************************************** * This function returns a printable string for a thread type. *************************************************************************************** * @ type : thread type. * returns pointer on string. **************************************************************************************/ char * thread_type_str( uint32_t type ); /*************************************************************************************** * This function is used by the pthread_create() system call to create a "new" thread * in an existing process. It allocates memory for an user thread descriptor in the * local cluster, and initializes it from information contained in the arguments. * The CPU context is initialized from scratch. * It is registered in the local process descriptor specified by the argument. * The THREAD_BLOCKED_GLOBAL bit is set => the thread must be activated by the caller * to start at the next scheduling point. *************************************************************************************** * @ pid : process identifier. * @ start_func : pointer on entry function. * @ start_args : pointer on function argument (can be NULL). * @ attr : pointer on pthread attributes descriptor. * @ new_thread : [out] address of buffer for new thread descriptor pointer. * @ returns 0 if success / returns ENOMEM if error. **************************************************************************************/ error_t thread_user_create( pid_t pid, void * start_func, void * start_arg, pthread_attr_t * attr, thread_t ** new_thread ); /*************************************************************************************** * This function is used by the sys_fork() system call to create the "child" thread * in the local cluster. It allocates memory for a thread descriptor, and initializes * it from the "parent" thread descriptor defined by the argument. * The new thread is attached to the core that has the lowest load in local cluster. * It is registered in the "child" process defined by the argument. * This new thread inherits its user stack from the parent thread, as it uses the * Copy-On-Write mechanism to get a private stack when required. * The content of the parent kernel stack is copied into the child kernel stack, as * the Copy-On-Write mechanism cannot be used for kernel segments (because kernel * uses physical addressing on some architectures). * The CPU and FPU execution contexts are created and linked to the new thread. * but the actual context copy is NOT done, and must be done by by the sys_fork(). * The THREAD_BLOCKED_GLOBAL bit is set => the thread must be activated to start. *************************************************************************************** * @ parent_thread_xp : extended pointer on parent thread descriptor. * @ child_process : local pointer on child process descriptor. * @ child_thread : [out] address of buffer for child thread descriptor pointer. * @ returns 0 if success / returns -1 if error. **************************************************************************************/ error_t thread_user_fork( xptr_t parent_thread_xp, process_t * child_process, thread_t ** child_thread ); /*************************************************************************************** * This function is called by the process_make_exec() function to re-initialise the * thread descriptor of the calling thread (that will become the new process main * thread), and immediately jump to user code without returning to kentry!!! * It must be called by the main thread of the calling process. * - A new user stack vseg is created and initialised. * - The kernel stack (currently in use) is not modified. * - The function calls the hal_cpu_context_exec() to re-initialize the CPU context * an jump to user code. *************************************************************************************** * @ entry_func : main thread entry point. * @ argc : number of main thread arguments. * @ argv : array of pointers on stringarguments. * @ returns 0 if success / returns ENOMEM if error. **************************************************************************************/ error_t thread_user_exec( void * entry_func, uint32_t argc, char ** argv); /*************************************************************************************** * This function allocates memory for a kernel thread descriptor in the local cluster, * and initializes it from arguments values. * It is called by kernel_init() to statically create all DEV server threads * It is also called to dynamically create RPC threads when required. * The THREAD_BLOCKED_GLOBAL bit is set, and the thread must be activated to start. *************************************************************************************** * @ new_thread : address of buffer for new thread pointer. * @ type : kernel thread type. * @ func : pointer on function. * @ args : function arguments. * @ core_lid : local core index. * @ returns 0 if success / returns ENOMEM if error **************************************************************************************/ error_t thread_kernel_create( thread_t ** new_thread, thread_type_t type, void * func, void * args, lid_t core_lid ); /*************************************************************************************** * This function is called by the kernel_init() function to initialize the IDLE thread * descriptor from arguments values. * The THREAD_BLOCKED_GLOBAL bit is set, and the thread must be activated to start. * It returns a kernel panic if failure. *************************************************************************************** * @ thread : pointer on existing thread descriptor. * @ type : kernel thread type. * @ func : pointer on function. * @ args : function arguments. * @ core_lid : local core index. **************************************************************************************/ void thread_idle_init( thread_t * thread, thread_type_t type, void * func, void * args, lid_t core_lid ); /*************************************************************************************** * This function is called by the sched_handle_signals() function to releases * the physical memory allocated for a thread in a given cluster, when this thread * is marked for delete. This include the thread descriptor itself, the associated * CPU and FPU context, and the physical memory allocated for an user thread local stack. * The destroyed thread is removed from the local process th_tbl[] array, and returns * true when the destroyed thread was the last thread registered in process. *************************************************************************************** * @ thread : pointer on the thread descriptor to release. * @ return true, if the thread was the last registerd thread in local process. **************************************************************************************/ bool_t thread_destroy( thread_t * thread ); /*************************************************************************************** * This function defines the code of the thread executed by all cores after kernel_init, * or when no other thread is runnable for a given core. * It enter and infinite loop in wich: * - it unmask the IRQs * - it optionally calls the hal_core_sleep() function to reduce the power consumption * (this behavior is controlled by the CONFIG_THREAD_IDLE_MODE_SLEEP flag). * - it call the sched_yield() function to find another runnable thread. * * TODO: In the TSAR architecture the hal_core_sleep() function forces the core to * low-power mode. Any IRQ will force the core to exit this low-power mode, but no ISR * is executed. We must analyse if we have the same behaviour for I86 architectures... **************************************************************************************/ void thread_idle_func( void ); /*************************************************************************************** * This function is used by a "blocker" thread running in the same cluster as a "target" * thread to request the scheduler of the target thread to acknowledge that the target * thread is blocked and not running, at the next context switch. * This function executes atomically the following actions : * - it set the request_pending boolean in the target scheduler descriptor. * - it set the REQ_ACK flag in the "flags" field of the target thread descriptor. * - It registers the responses counter pointer in the target thread descriptor. * The request_pending flag is handled as a set/reset flip-flop by the "blocker" thread * and by the "target" scheduler. *************************************************************************************** * @ target : local pointer on target thread. * @ ack_rsp_count : local pointer on responses counter. **************************************************************************************/ void thread_set_req_ack( thread_t * target, uint32_t * ack_rsp_count ); /*************************************************************************************** * This function is used by the sched_handle_signal() function executed by the * scheduler of a "target" thread to reset a "blocked not running" acknowledge request * in both the target thread descriptor, and in the target thread scheduler. *************************************************************************************** * @ target : local pointer on target thread. **************************************************************************************/ void thread_reset_req_ack( thread_t * target ); /*************************************************************************************** * This function checks if the calling thread can deschedule. *************************************************************************************** * @ returns true if no locks taken. **************************************************************************************/ inline bool_t thread_can_yield(); /*************************************************************************************** * This function implements the delayed descheduling mechanism : It is called by * all lock release functions, and calls the sched_yield() function when all locks * have beeen released and the calling thread THREAD_FLAG_SCHED flag is set. **************************************************************************************/ void thread_check_sched( void ); /*************************************************************************************** * This function is used by the four sys_thread_cancel(), sys_thread_exit(), * sys_kill() and sys_exit() system calls to mark for delete a given thread. * It set the THREAD_BLOCKED_GLOBAL bit and set the the THREAD_FLAG_REQ_DELETE bit * in the thread descriptor identified by the argument, to ask the scheduler * to asynchronously delete the target thread, at the next scheduling point. * The calling thread can run in any cluster, as it uses remote accesses, but * the target thread cannot be the main thread of the process identified by the , * because the main thread must be deleted by the parent process argument. * If the target thread is running in "attached" mode, and the argument * is false, this function implements the required sychronisation with the joining * thread, blocking the calling thread until the pthread_join() syscall is executed. *************************************************************************************** * @ thread_xp : extended pointer on the target thread. * @ pid : process identifier (to get the owner cluster identifier). * @ is_forced : the deletion does not depends on the attached mode. **************************************************************************************/ void thread_delete( xptr_t thread_xp, pid_t pid, bool_t is_forced ); /*************************************************************************************** * This function registers a blocking cause defined by the argument * in a remote thread descriptor identified by the argument. * We need an extended pointer, because this function can be called by another thread * than the target thread, executing the sys_kill() function. * WARNING : this function does not deschedule the target thread, and the descheduling * must be explicitely forced by a sched_yield(). *************************************************************************************** * @ thread_xp : extended pointer on remote thread descriptor. * @ cause : mask defining the cause (one hot). **************************************************************************************/ void thread_block( xptr_t thread_xp, uint32_t cause ); /*************************************************************************************** * This function resets the bit identified by the argument in a remote * thread descriptor identified by the argument. * We need an extended pointer, because the client thread of an I/O operation on a * given device is not in the same cluster as the associated device descriptor. * WARNING : this function does not reschedule the remote thread. * The scheduling can be forced by sending an IPI to the core running the remote thread. *************************************************************************************** * @ thread_xp : extended pointer the remote thread. * @ cause : mask defining the cause (one hot). * @ return non zero if the bit-vector was actually modified / return 0 otherwise **************************************************************************************/ uint32_t thread_unblock( xptr_t thread_xp, uint32_t cause ); /*************************************************************************************** * This function updates the calling thread user_time or kernel_time counters. *************************************************************************************** * @ thread : local pointer on target thread. * @ is_user : update user time if non zero / update kernel time if zero **************************************************************************************/ void thread_time_update( thread_t * thread, uint32_t is_user ); /*************************************************************************************** * This function returns the extended pointer on a thread descriptor identified * by its thread identifier, and process identifier. * It can be called by any thread running in any cluster. *************************************************************************************** * @ pid : process identifier. * @ trdid : thread identifier. * @ return the extended pointer if thread found / return XPTR_NULL if not found. **************************************************************************************/ xptr_t thread_get_xptr( pid_t pid, trdid_t trdid ); #endif /* _THREAD_H_ */