EP0868690A1 - Job scheduling for instruction processor - Google Patents
Job scheduling for instruction processorInfo
- Publication number
- EP0868690A1 EP0868690A1 EP96943458A EP96943458A EP0868690A1 EP 0868690 A1 EP0868690 A1 EP 0868690A1 EP 96943458 A EP96943458 A EP 96943458A EP 96943458 A EP96943458 A EP 96943458A EP 0868690 A1 EP0868690 A1 EP 0868690A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- signal
- processor
- job
- instruction processor
- instruction
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
Links
Classifications
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F9/00—Arrangements for program control, e.g. control units
- G06F9/06—Arrangements for program control, e.g. control units using stored programs, i.e. using an internal store of processing equipment to receive or retain programs
- G06F9/46—Multiprogramming arrangements
- G06F9/48—Program initiating; Program switching, e.g. by interrupt
- G06F9/4806—Task transfer initiation or dispatching
- G06F9/4843—Task transfer initiation or dispatching by program, e.g. task dispatcher, supervisor, operating system
- G06F9/4881—Scheduling strategies for dispatcher, e.g. round robin, multi-level priority queues
-
- G—PHYSICS
- G06—COMPUTING; CALCULATING OR COUNTING
- G06F—ELECTRIC DIGITAL DATA PROCESSING
- G06F9/00—Arrangements for program control, e.g. control units
- G06F9/06—Arrangements for program control, e.g. control units using stored programs, i.e. using an internal store of processing equipment to receive or retain programs
- G06F9/46—Multiprogramming arrangements
- G06F9/48—Program initiating; Program switching, e.g. by interrupt
- G06F9/4806—Task transfer initiation or dispatching
- G06F9/4812—Task transfer initiation or dispatching by interrupt, e.g. masked
Definitions
- This invention pertains to the scheduling of jobs for execution by an instruction processor included in a central processing system.
- Some processing systems such as the Ericsson APZ 212 20, use a signal processor to schedule jobs for execution by an instruction processor, thereby enabling very rapid context switching between jobs executed by the instruction processor.
- the context switching time is very fast in such systems compared to most other processors .
- each job has a signal associated therewith.
- the signal contains information which advises the instruction processor as to which block of code (e.g., in a program store) should be executed by the instruction processor in connection with the job, and data to be utilized in such execution.
- a new signal (associated with a new job) is obtained by the signal processor and forwarded to the instruction processor.
- the new signal is obtained by the signal processor from a selected one of a plurality of job buffers of the signal processor, the new signal being obtained in priority order.
- the new job obtained from the signal processor may be totally unrelated to the old job, and accordingly may use entirely different data.
- other jobs are arriving from external sources (e.g., other processing systems) and, when of a higher priority, such jobs interrupt execution of the old job before the old job exits.
- the code and data changes context very often. This means that the context is lost so often that nothing is gained by using fast memories (e.g., cache memories) for saving the contexts.
- fast memories e.g., cache memories
- the only context save that is used is to store data in registers, which can only be done during execution of one job.
- FIG. 1 shows portions of a central processing unit 20, specifically a instruction processor unit (IP) 22; a signal processing (SP) unit 24; program store (PS) 26; data and reference store (DRS) 28; a plurality of regional processor bus handlers (RPHs) 30 1; n ; an "other" processor bus handlers (IPH) 31, and, a maintenance unit (MAU) 32.
- IP instruction processor unit
- SP signal processing
- PS program store
- DRS data and reference store
- RPHs regional processor bus handlers
- IPH "other" processor bus handlers
- MAU maintenance unit
- Each of instruction processor 22, signal processor 24, IPHB 31, and RPHs 30 are independent processors.
- Instruction processor 22 executes jobs, each job corresponding to a block of instructions stored in program store (PS) 26.
- Signal processor 24 serves as a scheduler of jobs for instruction processor 22.
- signal processor 24 receives a "signal", e.g., from the outside world or from instruction processor 22.
- a signal is an instruction telling where to execute in a specific part of a block of instructions, the signal including data to be utilized in execution of the block.
- Signal processor 24 analyses and prepares incoming signals, and assigns priority to these signals before they are sent to the instruction processor 22.
- a reference portion of data and reference store 28 contains information describing the signals, the blocks, and the variables used in the system.
- central processing system 20 of Fig. 1 includes two instruction processors 22, two signal processors 24, one or other processor bus handlers (IPHs) 31, and a further plurality of regional processor bus handlers 30, all connected in a mirror image of Fig. 1 via MAU 32 and buses 34 and 36.
- each instruction processor 22 is provided with its own program store 26 and its own data and reference store 28.
- Regional processor bus handlers (RPHs) 30 1( .. n are connected by corresponding regional processor busses 3 8 ⁇ ,...n to unillustrated regional processors. Similarly, one or more other processor bus handlers 31 can also be provided for connection to a suitable bus 39. Both regional processor bus handlers (RPHs) 30 x n and other processor bus handlers, as well as signal processor 24, serve to decrease the load on instruction processor 22, as instruction processor 22 is involved in executing application software stored in program store 26.
- Fig. 2 shows, in more detail, instruction processor 22, signal processor 24, other processor bus handler 31, and regional processor bus handlers (RPHs) 30 ⁇ , ... n °f central processing system 20, and interactions therebetween.
- signal processor 24 shows signal processor 24 as comprising a job scheduler 40 and a plurality of job buffers 42A - 42D, also known as buffers A - D, respectively.
- signal processor 24 retrieves a next job to be executed from the one of buffers 42A - 42D which has the highest priority and yet is non-empty. Further, signal processor 24 sends the signal associated with the job next to be executed to instruction processor 22. Receipt of such signal prompts instruction processor 22 to start its execution at the new block of code specified by the signal.
- instruction processor 22 prompt instruction processor 22 itself to generate a new signal.
- instruction processor-generated signals are of various types: combined signals, RP signals, other instruction processor signals, and buffered signals.
- a combined signal is much like a subroutine call, and results in instruction processor 22 immediately executing the combined signal and then returning to execute the job from which the combined signal was generated.
- the RP signals and other instruction processor signals generated by instruction processor 22 are signals associated with jobs to be executed either by a regional processor (in the case of RP signals) or another instruction processor (in the case of an IP signal) .
- An RP signal or other IP signal is received by signal processor 24 and is directed to an appropriate one of the regional processor bus handlers 30 or (in the case of an other IP signal) to an other processor bus handler 31 (in the case of an RP signal) .
- An IP-generated signal, other than a combined signal, which is generated by instruction processor 22 for execution by instruction processor 22, is referred to as a "buffered signal" .
- the buffered signal is sent to signal processor 24 (as represented by line 54 in Fig. 2) .
- Execution by instruction processor 22 continues in the block instruction processor 22 is currently executing.
- signal processor 24 takes one of two potential actions depending upon priority level of the received buffered signal.
- the priority level of the received buffered signal is greater than the priority level of the job currently being executed by instruction processor 22 (i.e., the job which generated the buffered signal) , then signal processor 24 sends an interrupt to instruction processor 22 to interrupt the current job (as represented by line 56 in Fig. 2) . Otherwise, signal processor 24 puts the buffered signal as the last job in the one of the job buffers 42A - 42D having the same priority as the buffered signal. In such manner, the buffered signal is executed as any other signal of the same priority as the buffered signal (as represented by line 58 in Fig. 2) .
- Central processing system 20 has numerous implementations including, for example, as a control system for a telephone switching system.
- a control system for a telephone switching system is the APZ 212 20 control system for the Ericsson AXE 10 switch, as described by Egeland, Terje, "APZ 21220 -- The New High- end Processor for AXE 10", Ericsson Review. No. 1, 1995, pp. 5 - 12, which is incorporated herein by reference.
- Scheduling of signals for execution by an instruction processor is primarily performed by a signal processor.
- the signal processor has a unique scheduling technique and the instruction processor performs some of its own scheduling (using a "current list” memory) without disturbing the signal processor.
- the signal processor allocates signals to be executed into one of four buffers according to an assigned priority of the signal, e.g., into scheduling buffer A, scheduling buffer B, scheduling buffer C, or scheduling buffer D.
- an instruction processor needs a new signal for execution from the signal processor (as occurs upon receiving an EXIT signal from the instruction processor)
- the signal is fetched from buffers A - D in accordance with age (oldest) and priority level (i.e., level A, B, C, or D) .
- age oldest
- priority level i.e., level A, B, C, or D
- the signal processor determines whether any jobs of similar priority level are currently interrupted and, if so, resumes execution of the interrupted job while sending the fetched job back to the appropriate one of the its buffers. Moreover, should the instruction processor be executing a level D signal at the time the signal processor receives a signal of higher priority (e.g, from the instruction processor, from a regional processor, or from an "other" instruction processor) , execution of the level D signal by the instruction processor is immediately interrupted.
- a signal of higher priority e.g, from the instruction processor, from a regional processor, or from an "other" instruction processor
- Execution of a signal by the instruction processor may cause generation of a new signal.
- Such instruction processor-generated signals are typically generated just before the EXIT instruction of a signal.
- Such instruction processor-generated signals can be combined signals or buffered signals (both of which are to be executed by the instruction processor) or a signal destined for another processor (such as a regional processor or an "other" instruction processor) .
- a combined signal is much like a subroutine call, and results in the instruction processor immediately executing the combined signal and then returning to execute the signal in which the combined signal was generated.
- the instruction processor puts the buffered signal in a special register or queue known as the "current list" . If the buffered signal happens to be generated immediately before exit of the currently executing job, is of any but the lowest priority level, and if no interrupt is set, the job associated with the buffered signal is executed upon exiting from the job in which the buffered signal is generated.
- the instruction processor can perform any one of several alternative steps depending upon the priority level of the buffered signal and depending upon whether any interrupts have been set.
- a first such alternative includes obtaining the first (next) job from the current list and executing the same.
- a second such alternative step includes returning scheduling control to the signal processor, as occurs when the buffered signal is of a lowest priority level.
- a third such alternative step includes transferring the entire contents of the current list to the signal processor, as occurs when an interrupt has occurred. In connection with the first alternative, consecutive jobs on the current list can be consecutively executed as jobs on the current list are exited.
- Whether or not a job associated with a buffered signal is executed immediately after the job which generates the buffered signal depends on the whether the buffered signal is generated immediately before a predetermined type of instruction (e.g, an EXIT instruction) .
- a predetermined type of instruction e.g, an EXIT instruction
- an instruction causing generation of a buffered signal must be in a predefined order within a job to have the buffered signal executed immediately upon termination of the job. Otherwise, the job associate with the buffered signal is subject to remaining on the current list and being executed subsequently to jobs associated with other buffered signals, or even being transferred to the signal processor.
- the entire contents of the current list is transferred to the signal processor.
- the signal processor then puts the signals from the current list into appropriate ones of its buffers in accordance with priority levels of the transferred signals.
- the signal processor also has the capability of sending signals to the current list.
- the signal processor transmits a signal to the instruction processor for execution, the signal processor searches its buffer(s) and transfers to the current list another signal in its buffer (s) that has a same thread identification as the signal being transferred to the instruction processor.
- a similar posting of a signal on the current list occurs when the signal processor determines that the thread ID of the externally-generated signal (e.g., received via either a regional processor bus handler or a processor bus handler) is the CurrentThreadID being processed by the instruction processor but did not result in an interrupt or setting of an interrupt flag.
- Fig. 1 is a schematic diagram of at least a portion of a central processing unit.
- Fig. 2 is a schematic diagram showing various constituent elements provided for a central processing system in accordance with the prior art.
- Fig. 3 is a schematic diagram showing various constituent elements provided for a central processing system in accordance with an embodiment of the present invention.
- Fig. 4 is a schematic diagram showing one illustration of a configuration of an instruction processor provided for the central processing system of Fig. 3.
- Fig. 5 is a schematic diagram showing various constituent elements provided for a multi-instruction processor-based central processing system in accordance with another embodiment of the present invention.
- Fig. 6 is a schematic diagram depicting events encountered and states experienced by a signal processor of the central processing system of Fig. 3.
- Fig. 7 is a schematic diagram depicting events encountered and states experienced by an instruction processor of the central processing system of Fig. 3.
- Fig. 8(1) is a flowchart showing steps executed by a signal processor upon encountering an EXIT signal from an instruction processor.
- Fig. 8(2) is a flowchart showing steps executed by a signal processor upon encountering a (non-exit) signal from an instruction processor.
- Fig. 8(3) is a flowchart showing steps executed by a signal processor upon encountering time out event.
- Fig. 8(4) is a flowchart showing steps executed by a signal processor upon encountering a signal from a regional processor (RP) or other instruction processor.
- RP regional processor
- Fig. 9(1) through Fig. 9(3) are schematic views showing steps executed by an instruction processor for performing actions A(SP)1 through A(SP)3, respectively.
- Fig. 9(4) is a flowchart showing steps performed by an instruction processor for performing action A(SP) .
- Fig. 9(5) through Fig. 9(10) are schematic views showing steps executed by an instruction processor for performing actions A(SP)5 through A(SP)10, respectively.
- Fig. 9(11) is a flowchart showing steps performed by an instruction processor for performing action A(SP) 11
- Fig. 10 is a schematic view of a format of a signal utilized by the present invention.
- Central processing system 120 of Fig. 3 includes instruction processor unit (IP) 122; a signal processing (SP) unit 124; program store (PS) 126; data and reference store (DRS) 128; a plurality of regional processor bus handlers (RPHs) 130- ⁇ n ; and, "other" processor bus handler(s) (IPB) 131.
- IP instruction processor unit
- SP signal processing
- PS program store
- DRS data and reference store
- RSHs regional processor bus handlers 130- ⁇ n
- IPB "other" processor bus handler(s) 131.
- similarly named elements of system 120 are the same as the afore- described elements of system 20 of Fig. 2.
- a current list memory 150 which is stored in a set of registers of instruction processor 122 for access by instruction processor 122.
- signal processor 124 has a timer 141.
- Central processing system 120 of Fig. 3 is realized in the illustrated embodiment utilizing a Sun Ultra 2 workstation, which provides two processors working with shared memory.
- Sun Ultra 2 workstation which provides two processors working with shared memory.
- the persons skilled in the art understands how to send signals between two processors through shared memory techniques.
- Instruction processor 122 and signal processor 124 operate in a different manner than do corresponding processors of the prior art.
- instruction processor 122 selectively stores buffered signals which it generates on its current list 150, thereby bypassing signal processor 124 and providing better context preservation.
- Signal processor 124 allows one or more buffered signals in current list 150 to be executed so long as a time limit is not exceeded. Further, when signal processor 124 has a job of a higher priority level, signal processor 124 always interrupts "D" priority level jobs in the middle of job execution by instruction processor 122. Signal processor 124 further allows "A" priority level jobs to interrupt other jobs upon signal sending.
- Fig. 4 shows one configuration of instruction processor 122.
- instruction processor 122 has central processing unit (CPU) 160; a register memory 162; fast memory 164; memory access/interface 166; a plurality of cache memories 168A - 168C; a plurality of memory cards 170A - 170G; and, a memory bus 172 for connecting memory access/interface 166 to cards 170.
- cache memory 168A has a 128-byte access
- - cache memory 168B has a 16-byte access
- cache memory 168C has a 4-byte access.
- Cards 170A - 170F are DRAM main memory cards.
- Card 170G is a direct memory access (DMA) card connected by IOB bus to peripheral devices such as disk drive controllers, making it possible to uses other memory devices such as disks.
- DMA direct memory access
- fast memory 164 is utilized to access variables that are very frequently used, such as data structures for locking and for keeping track of disk buffers.
- variables that are very frequently used such as data structures for locking and for keeping track of disk buffers.
- An allocation of variables to specific memory types can be accomplished through the compiler or by the designer.
- Cache memories 168A - 168C have varying line sizes to offer flexibility. Variables which should be cached are also specifiable as a block parameter or variable type.
- Fig. 10 shows the format of a signal utilized by one embodiment of the present invention.
- the signal includes a first field "ThreadID” indicative of the thread to which the signal belongs; a second field “JobLevel” indicative of the priority level of the signal; a third field “FORMAT” indicated of the number of data items in the last field of the signal; a fourth field “SignalNumber” indicative of a sequence number of the signal; a sixth field “RecBlock” which is the receiving block number; and seventh field “SendBlock” which is the sending block number,- an eighth field “Forlopp Id” which is an identification utilized for reliability purposes; a ninth field "RegPRO” which contains a first data value; and, a tenth field “DataList” which contains one or more (as many as twenty four) other data values.
- a thread includes the notion of a set of jobs which are necessary to execute in response to a message received from an outside system (e.g. , from a regional processor or an "other" instruction processor) .
- an outside system e.g. , from a regional processor or an "other" instruction processor
- jobs can be executing simultaneously and communication with outside systems can be occurring as part of the thread.
- signal processor 124 has three states: an IDLE state; a WORKING state; and a QUEUED state. Changes of state are shown by boldface lines in Fig. 6. Fig. 6 also shows that signal processor 124 encounters four "SP" events, in particular events E(SP)1 through E(SP)4. Signal processor 124 can be in any one of its three states when it encounters an SP event. For this reason, each SP event in Fig. 6 is shown incident upon each state (by broken lines) .
- an "action” can include one or more steps, which steps can be executed either alternatively or successively. Actions performed by signal processor 124, and the steps constituting each action, are illustrated in Fig. 8(1) through 8(4) , respectively. At times, the steps executed pursuant to such actions depend upon the "state" of signal processor 124.
- instruction processor 122 has three states: an IDLE state,- a WORKING state; and a COMBINED/WORKING state.
- states of instruction processor 122 and signal processor 124 are not to be confused, as each state is independent.
- changes of state are shown by boldface lines in Fig. 7.
- Fig. 7 also shows that signal processor 124 encounters eleven "IP" events, in particular events
- IP events E(IP)1, E(IP)3, E(IP)9 occur in connection with actions performed by signal processor 124.
- IP 122 are correlated so that certain IP events occur only when instruction processor 124 is in one or more specified ones of its states.
- actions performed by instruction processor 122 are shown within circles depicting the states in which the actions may occur. States in which the IP events are encounterable are indicated by broken line connections in Fig. 7. Steps involved with IP actions E(IP)1 through E(IP)11 are shown in more detail in Figs. 9(1) - 9(11), respectively. As understood with respect to Figs. 9(1) - 9(11) as described below, various actions performed by instruction processor 122 create the SP events E(SP)1 - E(SP)2 shown in Fig. 6.
- Signal processor 124 operates in conjunction with its timer 141 (see Fig. 3) .
- timer 141 When loaded with a particular time value (e.g, value "X" or "Y") , timer 141 notifies signal processor 124 when a time interval corresponding to the time value has expired. Expiration of the time value, e.g., notification by timer 141, causes a time out event [event E(SP)3] , described in more detail with reference to Fig. 8(3) .
- Time out events enable signal processor 124 to know whether an action of instruction processor 122 is taking too much time. In this regard, upon initiation of certain operations (e.g.
- timer 141 is set for a value "X” (e.g., 1 ms) . If a time out occurs without timer 141 having been reset to value "X”, signal processor 124 sets the flag SP_Interrupt to note that instruction processor 122 has been executing jobs of the same thread ID for one time interval. Timer 141 is then loaded with a second time value "Y" (e.g., 3 ms) . Action taken, should a second time out occur after expiration of time value "Y” , depends on the priority level of the executing job. If the executing job is of "C” or "D" priority level, the executing job is interrupted. If the executing job is of "A" or "B” priority level, an error condition is noted an a KILL signal is issued. Actions performed by signal processor 124 upon receipt of SP events are described below:
- instruction processor 122 may generate a non-exit signal and assign a priority level for the generated signal .
- signal processor 124 sees event E(SP)2 as shown in Fig. 6.
- signal processor 124 Upon receipt of event E(SP)2, signal processor 124 performs action A(SP)2, the steps of which are illustrated in Fig. 8(2) .
- signal processor 124 discerns whether the signal received from instruction processor 122 is destined for one of the regional processors or an "other" instruction processor. If the signal received from instruction processor 122 is destined for one of the regional processors, at step 8 (2) -3 the signal is sent to an appropriate regional processor bus handler 130. If the signal received from instruction processor 122 is destined for one of an "other" instruction processor, at step 8 (2) -4 the signal is sent to "other" instruction processor bus handler 131.
- step 8 (2) -5 the priority level of the signal currently being executed by instruction processor 122 is checked at step 8 (2) -5. If the priority level of the currently executing signal is other than "D" level, at step 8(2) -6 the received signal is put last in an appropriate job buffer 42A - 42D in accordance with its priority. Otherwise, if the priority level of the currently executing signal is "D" level, then step 8 (2) -7 is executed. At step 8 (2) -7, switch Time-out is set to value "X"; flag Job_interrupted_level [D] is set active (to indicate that a job of priority level D is being interrupted) ; and an execution of the current ("D" level) job is interrupted.
- Instruction processor 122 sees the job interrupt as event E(IP)8, and responds with action A(IP) 8 as described in Fig. 9(8) .
- action A(SP)2 terminates as indicated by symbol 8 (2) -8.
- Event E(SP)1 from instruction processor 122 triggers Action A(SP)1, steps of which are shown in Fig. 8(1) .
- An EXIT signal may be received from instruction processor 122, and accordingly action A(SP)1 triggered, in the instances of instruction processor 122 completing execution of a job that does not result from generation of a buffered signal.
- an EXIT signal may be received when instruction processor 122 completes a job or sequence of jobs which did result from a buffered signal [see steps 9 (4) -6, 9 (4) -9, and 9 (4) -4 in Fig.
- signal processor 124 Upon receipt of an EXIT signal from instruction processor 122 [Event E(SP)1] , signal processor 124 fetches the first job from the non-empty buffer 142A - 142D with the highest priority [step 8(1)-1] . At step 8(1) -2, signal processor 122 clears various flags (Error_timeout and SP_Interrupt) and sets switch Time-out to a value "X”. At step 8(1) -3 and step 8(1) -4, the priority level of the job fetched at step 8(1)-1 is checked to determine whether the priority level is either "C" (step 8(1) -3) or "D" (step 8(1) -4) .
- step 8(1) -5 a flag Job_interrupted_level [C] is consulted to determine if the flag is active, i.e., whether execution by instruction processor 122 of another job of priority level C has already been interrupted by signal processor. If the determination at step 9(1) -5 is affirmative, step 8(1) -6 is executed.
- step 8(6)-l the job fetched at step 8(1)-1 is put back into the buffer from whence it was fetched; flag Job_interrupted_level (C) is set to be not active (since the previously interrupted level "C" job will now be executed and therefore is uninterrupted) ,- a flag Active_priority is set to "C" (to re-establish the priority level of the previously interrupted job) ; and the interrupted job is resumed.
- Resumption of interrupted job execution by signal processor 124 creates IP event E(IP)2, understood with reference to Fig. 9(2) .
- Action A(SP)1 then terminates (as indicated by symbol 8(l)-9) .
- step 8(1) -7 and step 8(1) -8 are executed.
- flag Active_priority is set to be the priority of the job fetched at step 8(1)-1; a signal associated with the fetched job is sent as IP event E(IP)l to instruction processor 122 (see Fig. 9(1)) ; and, CurrentThreadID is set to the thread ID of the fetched job.
- step 8(1) -8 the thread IDs of all jobs in the job buffers of priority level "C" or higher are checked and, if a job's thread ID is the same as the CurrentThreadID (i.e, the thread ID of the fetched job) , then a signal associated with each such job is sent to current list 150 in instruction processor 122.
- an IP event E(IP)11 is generated for each such job in the job buffer (s) (of level "C” or higher) which has a thread ID which is the same as CurrentThreadID.
- Action taken by instruction processor 122 in response to IP event E(IP)11 is described with reference to Fig. 9(11) .
- Action A(SP)1 then terminates (as indicated by symbol 8(1) -9) .
- step 8(1) -10 flags Job_interrupted_level [C] and Job_interrupted_level [C] are consulted to determine if execution by instruction processor 122 of jobs of either priority level "C" or "D" are currently interrupted by signal processor 124. If the check at step 8(1) -10 is affirmative (i.e., if either flag is active) , the job fetched at step 8(1) -1 is put back in the buffer [step 8(1) -11] and a further check is preformed at step 8(1) -12. Specifically, at step 8(1)- 12, a further discrimination is conducted to see if flag Job_interrupted_level [C] is active. If the result of step 8(1) -12 is affirmative, at step 8 (1) -13 flag
- Job_interrupted_level [C] is set to be not active and flag Active Priority is assigned the value "C” . If the result of step 8(1) -12 is negative, at step 8(1) -14 flag Job_interrupted_level [D] is set to be not active and flag Active_Priority is assigned the value "D” .
- signal processor 124 directs instruction processor 122 to resume execution of the interrupted job of highest priority by generating IP event E(IP)2. Thereafter, action A(SP)1 terminates as indicated by symbol 8(1)-16.
- step 8(1) -18 flag Active_priority is set to be the priority of the job fetched at step 8(1)-1; CurrentThreadID is set to the thread ID of the fetched job; and, a signal associated with the fetched job is sent as IP event E(IP)1 to instruction processor 122 (see Fig. 9(1)) , in similar manner to step 8(1) -7.
- step 8(1) -18 the thread IDs of all jobs in the job buffers (having priority level of "C" or higher) are checked and, if a job's thread ID is the same as the CurrentThreadID (i.e, the thread ID of the fetched job), then a signal associated with each such job is sent to current list 150 in instruction processor 122.
- a IP event E(IP)ll is generated for each such job in the job buffer which has a thread ID which is the same as CurrentThreadID.
- action taken by instruction processor 122 in response to IP event E(IP)11 is described with reference to Fig. 9(11) .
- steps 8(1) -19 and 8(1) -20 are executed prior to termination of action A(SP)1.
- Steps 8(1) -19 and 8 (1) -20 are similar to steps 8(1) -17 and 8(1) -18, and essentially result in all jobs in the buffer which have a thread ID which is the same as the CurrentThreadID being sent to the instruction processor's current list 150. Termination of action A(SP)1 is indicated by symbol 8(1) -21.
- signal processor 124 can send signals to regional processor bus handlers 30 and the "other" instruction processor bus handler 31
- signal processor 124 can receive signals externally generated from those handlers, as indicated by Event E(SP)4 in Fig. 6.
- Event E(SP)4 Upon receipt of such an externally-generated signal, Action A(SP)4 is preformed. The steps of action A(SP)4 are illustrated in Fig. 8(4) .
- signal processor 124 assigns a thread ID [step 8 (4) -2] .
- signal processor 124 can assign a thread ID by concatenating a processor ID and an internal counter that is incremented each time a new thread ID is assigned.
- step 8 124 examines the priority level of the externally- generated signal. If conditions of neither step 8 (4) -3 nor step 8 (4) -4 are satisfied, a thread ID condition of step 8 (4) -5 is checked. If the thread ID condition of step 8 (4) -5 is not satisfied, step 8 (4) -6 is executed.
- step A(SP)4-3 If, in step A(SP)4-3, the priority level of the externally-generated signal is greater than the priority level of the job currently being executing by instruction processor 122, and the job being executed by instruction processor 122 has the lowest ("D") level priority, signal processor 124 performs step 8 (4) -7.
- step 8 (4) -7 signal processor 124 sets switch Time-out to value "X” ,- sets flag Job_interrupted__level [D] as active (to indicate that a job of priority level "D" is interrupted) ,- and, sends an interrupt to instruction processor 122.
- Instruction processor 122 views the interrupt as IP event E(IP)8, a response to which is understood with respect to action A(IP)8 described in Fig. 9(8) .
- step 8 (4) -4 If, in step 8 (4) -4, the priority level of the externally-generated signal is the highest level (e.g., "A" level priority) and is greater than the priority level of the job currently being executing by instruction processor 122, at step 8 (4) -8 signal processor 124 sets a flag SP_Interrupt (which causes instruction processor 122 to execute the new signal upon termination of the job currently being executed) . Further, at step 8 (4) -7, signal processor 124 sets the value of switch Time-out to
- step 8(SP)4-5 signal processor 124 nevertheless determines if the thread ID of the externally-generated signal (received via either a regional processor bus handler 30 or a processor bus handler 31) is the CurrentThreadID being processed by instruction processor 122 and if the priority level of the externally-generated signal is greater than D-level. If so, at step 8 (4) -9 the externally-generated signal is sent to instruction processor 122 for entry onto current list 150. Upon receipt of such a signal [Event E(IP)9] , instruction processor 122 puts the externally-generated signal as the last entry in current list 150 (see Fig. 9(9)) .
- step 8 (4) -6 signal processor 124 puts the externally-generated signal in the appropriate one of job buffers 142A - 142D, according to the priority level of the externally-generated signal .
- action A(SP)4 terminates as indicated by symbol 8 (4) -10.
- Timer 41 can have a time out when the value stored for switch Time-out is clocked down to zero by timer 41.
- signal processor 124 sees the time out as event E(SP)3 (see Fig. 6) and performs action A(SP)3, and particularly the steps shown in Fig. 8(3) .
- signal processor 124 first checks at step 8(3)-l whether the flag SP_Interrupt has been set. If the flag has not been set, at step 8 (3) -2 timer 141 (Time-out) is set to value "Y" and flag SP_Interrupt is set before action A(SP)3 is terminated (as indicated by symbol 8 (3) -3) . If the flag has not been set, step 8 (3) -4 is next executed.
- step 8 (3) -4 the flag SP_Interrupt is cleared. Then, at step 8 (3) -5 a determination is made whether the job currently being executed by instruction processor 122 has a priority level of "C" or "D" . If the determination at step 8 (3) -5 is affirmative, step 8 (3) -6, step 8 (3) -7, and step 8 (3) -8 are consecutively executed prior to termination of action A(SP)3. At step 8 (3) -6, signal processor 124 fetches a first (oldest) job from a non-empty one of buffers 142A - 142D having the highest priority. Then, at step 8 (3) -7, the flag Job_interrupted_level [Active_priority] is set active.
- signal processor 124 notes that the time out will cause interruption of a currently executing job (having the priority level "Active_priority”) , and accordingly that the flag Job_interrupted_level must be set for the priority level of the interrupted job.
- the job currently being executed by instruction processor 122 (and during whose execution the time out occurred) is interrupted.
- interruption is seen by instruction processor 122 as IP event E(IP)8, a response to which is understood in connection with action A(IP)8 as described in Fig. 9(8) .
- step 8(3) -10 a signal KILL_SIGNAL is sent to instruction processor 122.
- Instruction processor views the signal KILL_SIGNAL as IP event E(IP)3, and develops a responsive action A(IP) 3 as shown in Fig. 9(3) .
- action A(SP)3 is terminated as indicated by symbol 8(3)- 3.
- IP-generated signals include signals destined for regional processors or other instruction processors, combined signals, and buffered signals. Events caused by IP-generated signals are shown in Fig. 7, and include event E(IP)11 corresponding to generation of a buffered signal; event E(IP)10 corresponding to generation of a combined signal or a HURRY signal; event E(IP)6 corresponding to generation of a signal for a regional processor or an "other" instruction processor.
- a HURRY signal is executed immediately by instruction processor
- a HURRY signal implies an exit without a return to the calling block.
- Actions performed by instruction processor 122 in response to IP events are as follows-.
- instruction processor 122 When in its IDLE state, instruction processor 122 performs action A(IP)1 shown in Fig. 9(1) .
- instruction processor 122 changes its state from IDLE to WORKING (see Fig. 7) .
- instruction processor 122 changes to a new block in its associated program store 126 and starts execution in the new block.
- instruction processor 122 Upon receipt of an interrupt [Event E(IP)8] , instruction processor 122 takes action A(IP)8 shown in Fig. 9(8) .
- instruction processor 122 saves its context. That is, instruction processor saves (e.g., in register memory 162) the block which was interrupted, its program counter, and the contents of its registers upon interruption. Then, at step 9 (8) -2, instruction processor 122 sends a signal to signal processor 124 for each job stored in current list 150, thereby effectively transferring the contents of current list 150 to signal processor 124. Thereafter, at step 9 (8) -3 instruction processor 122 changes to the new priority level of the interrupting signal and executes the job associated with the interrupting signal.
- instruction processor 122 When instruction processor 122 is to resume execution of an interrupted job, event E(IP)2 is encountered. Action A (IP) 2 taken in response to event E(IP)2 is shown in Fig. 9(2) .
- instruction processor 122 restores the context of the interrupted job (from the register memory 162 as understood from the foregoing) . Then, at step 9 (2) -2, instruction processor 122 changes to the priority level of the restored job and restarts execution of the signal associated with the restored job.
- event E(IP)6 occurs. Actions taken by instruction processor 122 in response to IP event E(IP)6 are shown in Fig- 9(6) . In action A(IP)6, instruction processor 122 merely sends such generated signal to signal processor 124 and continues execution in the currently executing block (e.g., the block from which either the regional processor or "other" instruction processor signal was generated) .
- instruction processor 122 When the code executed by instruction processor 122 requires generation of a combined signal or HURRY signal [Event E(IP)10] , instruction processor 122 immediately sets its state to COMBINED [see Fig. 7 and step 9(10)-1 of Fig. 9(10)] . Then, at step 9 (10) -2 instruction processor 122 saves the calling block (i.e., the block of instructions in which the Combined or HURRY signal was generated) and puts the return address for the calling block ' on the top of its stack. At step 9 (10) -3 instruction processor 122 changes to the new block required for execution by the combined or HURRY signal and begins execution at the beginning of that new block. (6) IP EXITING COMBINED OR HURRY SIGNAL When instruction processor 122 encounters an
- EXIT instruction of a combined or HURRY signal event E(IP)5 is encountered. Upon occurrence of event E(IP)5, action A(IP)5 as depicted in Fig. 9(5) is taken.
- instruction processor 122 restores the calling block (i.e., the block in which the combined or HURRY signal was generated) and returns the address of the next instruction for execution in the calling block from the stack of instruction processor 122.
- instruction processor 122 checks whether a flag "last Combined__Signal_return" has been set so as to indicate that the stack is empty and, if so, sets the state of instruction processor 122 to the WORKING state. Then, at step 9 (5) -3, instruction processor 122 resumes execution of the calling block at the instruction specified by the stack address.
- IP SENDING BUFFERED SIGNAL When an instruction executed by instruction processor 122 calls for generation of a buffered signal [Event E(IP)11] , instruction processor 122 responds with action A(IP)11 shown in Fig. 9(11) .
- the priority level of the currently executing job is evaluated to determine if it is of the lowest ("D") level. If so, at step 9(11) -2, the buffered signal is sent to signal processor 124 as event E(SP)2 [see Fig. 6] and execution in the buffer signal-generating block continues (as indicated by step 9 (11) -3) as action A(IP)11 terminates (as indicated by symbol 9 (11) -4.
- step 9 (11) -5 it is determined at step 9 (11) -5 whether the next instruction to be executed is an EXIT instruction and whether the flag SP_Interrupt has not been set. If both conditions of step 9 (11) -5 are affirmative, then (as indicated by step 9 (11) -6) the exit instruction is merged with and performed by instruction processor 122 as part of the signal sending instruction. Otherwise, if either of the conditions of step 9 (11) -5 are negative, instruction processor 122 puts the job associated with the buffered signal as the last job on current list 150 (step 9 (11) -7) . Upon completion of either step 9 (11) -6 or step 9 (11) -7, action A(IP)11 terminates as indicated by symbol 9 (11) -4.
- IP EXITING BUFFERED SIGNAL As instruction processor 122 executes a job associated with a buffered signal, instruction processor 122 eventually encounters an EXIT instruction [Event E(IP)4] . Upon encountering an EXIT instruction of a buffered-signal associated job, instruction processor 122 performs action A(IP) 4 depicted in Fig. 9(4) .
- a "buffered signal” not only includes a signal generated by the instruction processor 122 in the manner aforedescribed, but also encompasses all signals scheduled by signal processor 124 for instruction processor 122.
- instruction processor 122 conducts the checks indicated by steps 9(4)-l through 9 (4) -3 and, if all such checks are negative, executes step 9 (4) -4 before action A(IP)4 is terminated (as indicated by symbol 9 (4) -5) .
- instruction processor 122 determines if the job being executed is of the lowest priority level ( "D" level) . If so, at step 9(4)- ⁇ instruction processor 122 sets its state to IDLE, and then sends an EXIT signal to signal processor 124 and is handled by signal processor 124 (see Event E(SP)1 in Fig. 6) . Any remaining signals stored on current list 150 are not executed at this point.
- step 9 (4) -2 instruction processor 122 checks whether a flag SP_Interrupt has been set.
- SP_Interrupt can be set at step 8 (4) -7 of Fig. 8(4) when an externally-generated signal has a highest level priority and the currently executing job does not, or when a time-out has occurred [Action A(SP)3, step 8(3)- 2] . If the determination at step 9 (4) -2 is affirmative, steps 9 (4) -7 through 9 (4) -9 are executed prior to termination of action A(IP) .
- instruction processor 122 sets its state to IDLE. Then, at step 9 (4) -8, for each job stored in current list 150, instruction processor 122 sends a signal to signal processor 124 (effectively transferring the jobs from current list 150 in [order of from first to last] to signal processor 124) . The transfer of each such signal from current list 150 as seen by signal processor 124 as an event E(SP)2 [see Fig. 6 and action A(SP)2] . At step 9 (4) -9, instruction processor 122 sends an EXIT signal to signal processor 124, which EXIT signal is viewed as Event E(SP)1 and responded to with action A(SP)1 by signal processor 124.
- step 9 (4) -1-3 instruction processor 122 determines if current list 150 is not empty. If current list 150 is not empty, at step 9 (4) -10 instruction processor 122 fetches the signal associated with the first job in current list 150 and begins executing that first job. After step 9 (4) -10, action A(IP)4 terminates as indicated by symbol 9 (4) -5.
- step 9 (4) -4 instruction processor 122 sets its state to IDLE and sends an EXIT signal to signal processor 124, thereby indicating that there are no more jobs awaiting execution in current list 150.
- the EXIT signal is seen by signal processor 124 as Event E(SP)1 and responded to with action A(SP)1 by signal processor 124.
- action A(IP)4 terminates as indicated by symbol 9(4)- 5.
- instruction processor 122 can receive a signal from signal processor 124 that is to be put into current list 150. Such occurs particularly in performance by signal processor 124 of actions A(SP)1 [see, e.g., steps 8(l)-8, 8(1)-18, and 8(l)-20] and A(SP)4 [see, e.g., step 8 (4) -9] , and is viewed as event E(IP)9 by instruction processor 122.
- instruction processor 122 performs action A(IP) 9 which, as shown in Fig. 9(9) , is merely the posting of the signal as the last signal on current list 150 (see step 9 (9) -1) .
- a "KILL" signal can be generated by signal processor 124, as occurs (for example) during a time period expiration (see action A(SP)3, e.g., step 8 (3) -10) .
- Such a KILL signal is seen as event E(IP)3 by instruction processor 122, and is responded to by action A(IP)3 as shown in Fig. 9(3) .
- instruction processor 122 sets its state to IDLE.
- instruction processor 122 essentially discards the current thread.
- instruction processor 122 sends an EXIT signal to signal processor 124.
- Such EXIT signal is seen as signal processor 124 as event E(SP)1, and is responded to with action A(SP)1 [see Fig. 8(1)] in the manner previously discussed.
- (11) IP FORCED EXIT OF BUFFERED SIGNAL A forced exit instruction of a buffered signal occurs when the application programmer needs to ensure that the exit really exists. That is, a small delay must be inserted so that other threads have the possibility to execute.
- instruction processor 122 encounters event E(IP)7 and responds with action A(IP)7, the steps of which are depicted in Fig. 9(7) .
- instruction processor 122 sends to signal processor 124 a signal for each job remaining in current list 150, thereby effectively transferring the contents of current list 150 to signal processor 124. Thereafter, instruction processor 122 sets its state to IDLE (step 9 (7) -2) . Then, at step 9 (7) -3 instruction processor 122 sends an EXIT signal to signal processor 124. Such EXIT signal is seen as signal processor 124 as event E(SP)1, and is responded to with action A(SP)1 [see Fig. 8(1)] in the manner previously discussed.
- actions comparable to a forced exit can instead be accomplished by sending the signal with a time delay.
- Fig. 5 shows another embodiment of the present invention, and particularly features central processing system 220 which includes a plurality of instruction processors 222 x , 222 2 , ... 222 n in addition to signal processor 224, bus handlers 230, and a shared memory 227 (having both a program store and a data store) .
- Each instruction processor 222 of the embodiment of Fig. 5 can have the configuration above discussed with reference to Fig. 4.
- Blocks executing in a multi-IP environment such as Fig. 5 must be able to handle several concurrent executions within a block, or otherwise it must be verifiable that only one processor is executing in a block at a time (e.g., semaphores or some means of synchronizing different threads is necessary) .
- a system 220 such as shown in Fig. 5, it is also possible to allocate certain blocks to only one of the instruction processors 222.
- such allocated instruction processor 222 has some of its data in a special fast memory, thereby making it possible to execute certain jobs very efficiently.
- other instruction processors 222 would have to change context) .
- instruction processors of the present invention are involved in the scheduling of jobs which it executes, primarily by the instruction processors themselves entering jobs associated with buffered signals on current list 150 (as occurs, for example, in step 9 (11) -7 of action A(IP)11 [see Fig. 9(11)]) . If the buffered signal happens to be generated immediately before exiting of the currently executing job, is of any but the lowest priority level, and if no interrupt is set, the job associated with the buffered signal is executed upon exit from the job in which the buffered signal is generated [see step 9 (11) -6 of action A(IP)ll in Fig. 9(11)] .
- instruction processor can perform any one of several alternative steps depending upon priority level of the buffered signal and depending upon whether any interrupts have been set.
- a first such alternative includes obtaining the first (next) job from the current list and executing the same [see step 9 (4) -10 of action A(IP)4 in Fig. 9(4)] .
- a second such alternative step includes returning scheduling control to signal processor 124, as occurs when the buffered signal is of a lowest priority level [see step 9 (4) -6 of action A(IP)4 in Fig. 9(4)] .
- a third such alternative step includes transferring the entire contents of current list 150 to signal processor 124, as occurs when an interrupt has occurred [see step 9 (4) -8 of action A(IP)4 in Fig. 9(4)] .
- consecutive jobs on the current list can be consecutively executed as jobs on the current list are exited. That is, when a job fetched from current list 150 (as at step 9 (4) -10) is completed, its exit instruction creates (another) event E(IP)4 which, depending upon priority levels and interrupt status, can lead to execution of the next signal on current list 150.
- step 9 (11) -5 of Fig. 9(11) whether or not a job associated with a buffered signal is executed immediately after the job which generates the buffered signal depends on the whether the buffered signal is generated immediately before a predetermined type of instruction (e.g, an EXIT instruction) .
- a predetermined type of instruction e.g, an EXIT instruction
- an instruction causing generation of a buffered signal must be in a predefined order within a job to have the buffered signal executed immediately upon termination of the job. Otherwise, the job associate with the buffered signal is subject to remaining on current list 150 and being executed subsequently to jobs associated with other buffered signals, or even being transferred to signal processor 124.
- the signal is fetched from buffers 142A - 142B in accordance with age (oldest) and priority level (i.e., level A, B, C, or D) [see Action A(SP)1 of Fig. 8(1)] .
- Flags "Active_priority" and CurrentThread_ID are established in accordance with the priority level and thread ID of the fetched signal, and the fetched signal is sent to the instruction processor [(see step 8(1) -19 in Fig. 8(1)] .
- signal processor 124 sends to current list 150 any jobs in buffers 142A - 142B having the same thread ID as the fetched job [(see step 8(1) -20 in Fig. 8(1)] , so that jobs having the same thread ID can be executed in proximity.
- signal processor 124 also has the capability of sending signals to current list 150. Such particularly occurs when, as described above, the signal processor transfers to the current list another signal in its at least one buffer that has a same thread identification as the signal being transferred to the instruction processor.
- a similar posting of a signal on current list 150 occurs when signal processor 124 determines that the thread ID of the externally-generated signal (received via either a regional processor bus handler 30 or a processor bus handler 31) is the CurrentThreadID being processed by instruction processor 122 [see step A(SP)4-5 in Fig. 8(4)] .
- the signal processor determines whether any jobs of similar priority level are currently interrupted and, if so, resumes execution of the interrupted job while sending the fetched job back to the appropriate one of the buffers 142C or 142D. See Action A(SP)1 in Fig. 8 (1) .
- instruction processor 122 is provided with a plurality of current lists 150A - 150D, each one of the plurality of current lists being associated with a corresponding priority level . For example, jobs having an "A" priority level would be placed, where appropriate, on current list 150A; jobs having a "B" priority level would be placed, where appropriate, on current list 150B; and so forth.
- central processing systems can effectively employ very fast memory (e.g., cache memory) , since central processing systems of the present invention do not change context at a rate to nullify effects of such fast memories.
- the instruction processors of the present invention are able to reuse "cached" data. This means that data previously accessed in a thread can be reused.
- primary memory e.g., DRAM
- a buffer of more than one data word can be fetched at a time.
- much of the main memory access can be implemented as cache accesses, thereby reducing the load on the instruction processor.
- central processing systems relieve signal processor 124 from some of its work, as instruction processor 122 itself schedules, in current list 150, jobs associated with buffered signals.
- instruction processor 122 itself schedules, in current list 150, jobs associated with buffered signals.
- a significant work load reduction is realized for signal processor 124.
- the clock frequency of instruction processor 122 need not be bounded by the clock frequency of signal processor 124.
- Central processing systems of the present invention handles buffered signal scheduling faster than the described prior art method. Even though the number of main memory accesses decreases with the present invention, the memory bandwidth increases since instruction processor 122 will fetch much larger blocks of data at each main memory access.
- the signal processor Since, according to the present invention, there is more time between fetching of jobs from job buffers 142A- 142D by the signal processor, the signal processor has more time to prepare those jobs. Accordingly, the instruction processor stays in the IDLE state for a shorter time, when leaving control over to the signal processor, to fetch the next thread.
- the present invention is particularly beneficial for execution-intensive tasks that do not frequently interact with regional processors, e.g., transit switches based on CCITT No. 7 signaling, Home Location Registers (HLRs) , and Service Control Points (SCPs) .
- regional processors e.g., transit switches based on CCITT No. 7 signaling, Home Location Registers (HLRs) , and Service Control Points (SCPs) .
- the present invention advantageously provides externally-generated signals with thread IDS [see step A(SP)4-1 in Fig. 6A] , so that jobs belonging to the same thread are executed as one thread, thereby increasing the number of jobs which execute between context switches.
- the present invention also makes feasible emulation of certain devices, such as a central processor of an Ericsson AXE 10 switch, on RISC workstations, particularly since those workstations are provided with cache memories .
- the principles of the present invention do not necessarily require separate processors for the signal processor and the instruction processor.
- the present invention encompasses a single processor which emulates the distinct functions as herein described of both a signal processor and an instruction processor.
- IP instruction processor unit 22
- SP signal processing unit 24
- PS program store 26
- DRS data store 28
- RHs plurality of regional processor bus handlers
- IPB “other" processor bus handlers (IPB) 31 3 maintenance unit (MAU) 32 3 buses 34 and 36 3 bus 39 4 job scheduler 40 4 job buffers 42A - 42D 4 line 52 5 line 54 7 line 56 8 line 58 8 instruction processor unit (IP) 122 13 signal processing (SP) unit 124 13 program store (PS) 126 13 data store (DRS) 128 13 plurality of regional processor bus handlers (RPHs)
- RM (what is this?) 162 14 fast memory 164 14 memory access/interface 166 14 cache memories 168A - 168C 14 memory cards 170A - 170G 14 memory bus 172 14 line 154 17 line 152 22 central processing system 220 23 signal processor 224 23 bus handlers 230 23 shared memory227 23
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US574977 | 1990-08-30 | ||
US57497795A | 1995-12-19 | 1995-12-19 | |
PCT/SE1996/001706 WO1997022927A1 (en) | 1995-12-19 | 1996-12-19 | Job scheduling for instruction processor |
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EP (1) | EP0868690A1 (zh) |
JP (1) | JP2000502202A (zh) |
KR (1) | KR20000064491A (zh) |
CN (1) | CN1209207A (zh) |
AU (1) | AU714853B2 (zh) |
CA (1) | CA2240778A1 (zh) |
WO (1) | WO1997022927A1 (zh) |
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CN1316427C (zh) * | 2001-07-12 | 2007-05-16 | 杜莱布斯公司 | 产生与装置链的装置的缺陷相关的格式化信息的方法和系统 |
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SE9803901D0 (sv) * | 1998-11-16 | 1998-11-16 | Ericsson Telefon Ab L M | a device for a service network |
WO2000029942A1 (en) | 1998-11-16 | 2000-05-25 | Telefonaktiebolaget Lm Ericsson | Concurrent processing for event-based systems |
JP2001022600A (ja) * | 1999-07-06 | 2001-01-26 | Matsushita Electric Ind Co Ltd | ディジタル信号処理装置 |
KR101355295B1 (ko) * | 2006-08-29 | 2014-02-07 | 엔에이치엔엔터테인먼트 주식회사 | 온라인 게임에서 메시지 송신 제어 방법 및 장치 |
CN103246591B (zh) * | 2013-04-26 | 2016-01-27 | 华为技术有限公司 | 信号处理的方法和装置 |
CN108549578B (zh) * | 2017-12-25 | 2020-02-07 | 贵阳忆芯科技有限公司 | 一种中断聚合装置及其方法 |
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US4286322A (en) * | 1979-07-03 | 1981-08-25 | International Business Machines Corporation | Task handling apparatus |
DE3650158T2 (de) * | 1985-10-15 | 1995-04-06 | Unisys Corp | Sonderzweckprozessor zur Übernahme vieler Betriebssystemfunktionen in einem grossen Datenverarbeitungssystem. |
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- 1996-12-19 CN CN 96199957 patent/CN1209207A/zh active Pending
- 1996-12-19 KR KR1019980704692A patent/KR20000064491A/ko not_active Application Discontinuation
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- 1996-12-19 AU AU12188/97A patent/AU714853B2/en not_active Ceased
- 1996-12-19 CA CA 2240778 patent/CA2240778A1/en not_active Abandoned
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CN1209207A (zh) | 1999-02-24 |
AU1218897A (en) | 1997-07-14 |
KR20000064491A (ko) | 2000-11-06 |
CA2240778A1 (en) | 1997-06-26 |
AU714853B2 (en) | 2000-01-13 |
JP2000502202A (ja) | 2000-02-22 |
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