diff options
Diffstat (limited to 'nuttx/arch/x86/src/common/up_blocktask.c')
| -rw-r--r-- | nuttx/arch/x86/src/common/up_blocktask.c | 107 |
1 files changed, 51 insertions, 56 deletions
diff --git a/nuttx/arch/x86/src/common/up_blocktask.c b/nuttx/arch/x86/src/common/up_blocktask.c index b1653f1e4..dba388cb0 100644 --- a/nuttx/arch/x86/src/common/up_blocktask.c +++ b/nuttx/arch/x86/src/common/up_blocktask.c @@ -1,7 +1,7 @@ /**************************************************************************** * arch/x86/src/common/up_blocktask.c * - * Copyright (C) 2011 Gregory Nutt. All rights reserved. + * Copyright (C) 2011, 2013 Gregory Nutt. All rights reserved. * Author: Gregory Nutt <gnutt@nuttx.org> * * Redistribution and use in source and binary forms, with or without @@ -85,82 +85,77 @@ void up_block_task(struct tcb_s *tcb, tstate_t task_state) { + struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head; + bool switch_needed; + /* Verify that the context switch can be performed */ - if ((tcb->task_state < FIRST_READY_TO_RUN_STATE) || - (tcb->task_state > LAST_READY_TO_RUN_STATE)) - { - PANIC(OSERR_BADBLOCKSTATE); - } - else - { - struct tcb_s *rtcb = (struct tcb_s*)g_readytorun.head; - bool switch_needed; - - /* Remove the tcb task from the ready-to-run list. If we - * are blocking the task at the head of the task list (the - * most likely case), then a context switch to the next - * ready-to-run task is needed. In this case, it should - * also be true that rtcb == tcb. - */ + ASSERT((tcb->task_state >= FIRST_READY_TO_RUN_STATE) && + (tcb->task_state <= LAST_READY_TO_RUN_STATE)); - switch_needed = sched_removereadytorun(tcb); + /* Remove the tcb task from the ready-to-run list. If we + * are blocking the task at the head of the task list (the + * most likely case), then a context switch to the next + * ready-to-run task is needed. In this case, it should + * also be true that rtcb == tcb. + */ - /* Add the task to the specified blocked task list */ + switch_needed = sched_removereadytorun(tcb); - sched_addblocked(tcb, (tstate_t)task_state); + /* Add the task to the specified blocked task list */ - /* If there are any pending tasks, then add them to the g_readytorun - * task list now - */ + sched_addblocked(tcb, (tstate_t)task_state); - if (g_pendingtasks.head) - { - switch_needed |= sched_mergepending(); - } + /* If there are any pending tasks, then add them to the g_readytorun + * task list now + */ - /* Now, perform the context switch if one is needed */ + if (g_pendingtasks.head) + { + switch_needed |= sched_mergepending(); + } - if (switch_needed) + /* Now, perform the context switch if one is needed */ + + if (switch_needed) + { + /* Are we in an interrupt handler? */ + + if (current_regs) { - /* Are we in an interrupt handler? */ + /* Yes, then we have to do things differently. + * Just copy the current_regs into the OLD rtcb. + */ - if (current_regs) - { - /* Yes, then we have to do things differently. - * Just copy the current_regs into the OLD rtcb. - */ + up_savestate(rtcb->xcp.regs); - up_savestate(rtcb->xcp.regs); + /* Restore the exception context of the rtcb at the (new) head + * of the g_readytorun task list. + */ - /* Restore the exception context of the rtcb at the (new) head - * of the g_readytorun task list. - */ + rtcb = (struct tcb_s*)g_readytorun.head; - rtcb = (struct tcb_s*)g_readytorun.head; + /* Then switch contexts */ - /* Then switch contexts */ + up_restorestate(rtcb->xcp.regs); + } - up_restorestate(rtcb->xcp.regs); - } + /* Copy the user C context into the TCB at the (old) head of the + * g_readytorun Task list. if up_saveusercontext returns a non-zero + * value, then this is really the previously running task restarting! + */ - /* Copy the user C context into the TCB at the (old) head of the - * g_readytorun Task list. if up_saveusercontext returns a non-zero - * value, then this is really the previously running task restarting! + else if (!up_saveusercontext(rtcb->xcp.regs)) + { + /* Restore the exception context of the rtcb at the (new) head + * of the g_readytorun task list. */ - else if (!up_saveusercontext(rtcb->xcp.regs)) - { - /* Restore the exception context of the rtcb at the (new) head - * of the g_readytorun task list. - */ - - rtcb = (struct tcb_s*)g_readytorun.head; + rtcb = (struct tcb_s*)g_readytorun.head; - /* Then switch contexts */ + /* Then switch contexts */ - up_fullcontextrestore(rtcb->xcp.regs); - } + up_fullcontextrestore(rtcb->xcp.regs); } } } |