操作系统概念：进程调度算法（FCFS、RR）C++实现

#include "m_sched.h" #include "Compare.h" int m_sched::cur_run = -1; m_sched::m_sched ( void ) { } void m_sched::run ( strategy algo ) { event_style event = NOP; list< PCBs* >::iterator proc; list< PCBs* >::iterator wproc; int run_t = 0; switch ( algo ) { case FCFS: printf ( "Process\t\tArri_Time\tBurst_Time\tIO_Gap\tIO_Burst_Time\n" ); for ( list< PCBs* >::iterator itr = m_queue.begin(); itr != m_queue.end(); ++itr ) { printf("%d\t\t%d\t\t%d\t\t%d\t\t%d\n", (*itr)->pid_t, (*itr)->arri, (*itr)->burst, (*itr)->io_gap, (*itr)->io_burst ); } while ( !( m_queue.empty() && w_queue.empty() ) ) { if ( !w_queue.empty() ) { for ( list< PCBs* >::iterator itr = w_queue.begin(); itr != w_queue.end(); ++itr ) { if ( cur_run >= ( ( *itr )->arri + ( *itr )->io_burst ) ) { ( *itr )->io = false; ( *itr )->arri = ( ( *itr )->arri + ( *itr )->io_burst ); printf ( "\nPid %d finish IO operation at CPU time unit %d.\n", ( *itr )->pid_t, ( *itr )->arri ); m_queue.push_back ( *itr );//shift to ready queue m_queue.sort ( Compare() );//sort by arrive time w_queue.erase ( itr );//remove from waiting queue break; } } } if ( m_queue.empty() ){ ++ cur_run; continue; } proc = m_queue.begin();//get the first one of ready queue while ( cur_run < ( *proc )->arri ) {//waiting the process arrive Sleep ( 1000 ); ++ cur_run; } printf ( "\nEvent Process_Start at CPU time unit %d.\n", cur_run ); printf ( "Pid %d execute...", ( *proc )->pid_t ); stat.add_wait ( cur_run - ( ( *proc )->arri ) );//add up the waiting time while ( run_t < ( *proc )->burst ) {//execute process Sleep ( 1000 ); printf( "..." ); ++ run_t; ++ cur_run; if ( ( *proc )->io ) {//do io operation if ( run_t == ( *proc )->io_gap ) { printf ( "\nPid %d request for IO operation at CPU time unit %d.\n", ( *proc )->pid_t, cur_run ); ( *proc )->arri = cur_run;//modify process arrival time ( *proc )->burst -= run_t;//remain burst time ( *proc )->sta = waiting;//ready to waiting w_queue.push_back( *proc );//shift to waiting queue printf ( "Have been run %d\n", run_t ); break; } } } if ( !( *proc )->io ) { printf ( "\nRunning time is %d\n", run_t ); stat.add_turn ( ( *proc )->pid_t, cur_run ); } m_queue.pop_front();//pop the the first one of ready queue run_t = 0;//reset } stat.ave_wait ( MAX_PRO ); stat.ave_turn ( MAX_PRO ); break; case RR: printf ( "TimeSlice is %d\n", TimeSlice ); printf ( "Process\t\tArri_Time\tBurst_Time\tIO_Gap\tIO_Burst_Time\n" ); for ( list< PCBs* >::iterator itr = m_queue.begin(); itr != m_queue.end(); ++itr ) { printf("%d\t\t%d\t\t%d\t\t%d\t\t%d\n", (*itr)->pid_t, (*itr)->arri, (*itr)->burst, (*itr)->io_gap, (*itr)->io_burst ); } while ( !( m_queue.empty() && w_queue.empty() ) ) { if ( !w_queue.empty() ) { for ( list< PCBs* >::iterator itr = w_queue.begin(); itr != w_queue.end(); ++itr ) { if ( cur_run >= ( ( *itr )->arri + ( *itr )->io_burst ) ) { ( *itr )->io = false; ( *itr )->arri = ( ( *itr )->arri + ( *itr )->io_burst );//back to ready queue time printf ( "\nPid %d finish IO operation at CPU time unit %d\n", ( *itr )->pid_t, ( *itr )->arri ); m_queue.push_back ( *itr );//shift to ready queue m_queue.sort(); w_queue.erase ( itr );//remove from waiting queue break; } } } if ( m_queue.empty() ){ ++ cur_run; continue; } proc = m_queue.begin(); while ( cur_run < ( *proc )->arri ) {//waiting the process arrive Sleep ( 1000 ); ++ cur_run; } printf ( "\nEvent Process_Start at CPU time unit %d.\n", cur_run ); printf ( "Pid %d execute...", ( *proc )->pid_t ); stat.add_wait ( cur_run - ( ( *proc )->arri ) );//add up the waiting time while ( run_t < ( *proc )->burst && run_t < TimeSlice ) {//execute process Sleep ( 1000 ); printf( "..." ); ++ run_t; ++ cur_run; if ( ( *proc )->io ) {//do io operation if ( run_t == ( *proc )->io_gap ) { printf ( "\nPid %d request for IO operation at CPU time unit %d.\n",( *proc )->pid_t , cur_run ); ( *proc )->arri = cur_run;//modify process arrival time ( *proc )->burst -= run_t;//remain burst time ( *proc )->sta = waiting;//ready to waiting w_queue.push_back( *proc );//shift to waiting queue printf ( "Have been run %d\n", run_t ); break; } } } if ( run_t == TimeSlice && ( *proc )->burst != TimeSlice ) { printf ( "\nSwap out Pid %d\n", ( *proc )->pid_t ); ( *proc )->arri = cur_run;//modify process arrival time ( *proc )->sta = waiting;//ready to waiting m_queue.push_back( *proc );//shift to the end of queue } if ( !( *proc )->io ) ( *proc )->burst -= run_t;//remain burst time if ( !( *proc )->burst ) { printf ( "\nRunning time is %d\n", run_t ); stat.add_turn ( ( *proc )->pid_t, cur_run ); } m_queue.pop_front();//pop from ready queue run_t = 0;//reset } stat.ave_wait ( MAX_PRO ); stat.ave_turn ( MAX_PRO ); break; } } m_sched::~m_sched ( void ) { }