diff --git a/src/threads/fixed-point.h b/src/threads/fixed-point.h index 9b0140c..c0a6100 100644 --- a/src/threads/fixed-point.h +++ b/src/threads/fixed-point.h @@ -1,31 +1,95 @@ +#include #ifndef FIXED_POINT_H #define FIXED_POINT_H +typedef struct +{ + int32_t raw; +} fp32_t; + /* Fixed Point Arithmetic bit count constants */ -#define NUM_INT_BITS 11 #define NUM_FRAC_BITS 20 +#define NUM_INT_BITS (31 - NUM_FRAC_BITS) #define CONVERSION_CONST (1 << NUM_FRAC_BITS) /* f = 2^q, (2^20) */ /* Fixed Point Arithmetic conversion operations */ /* Converts an integer n to a fixed point number */ -#define INT_TO_FP(n) ((n) * (CONVERSION_CONST)) +inline fp32_t +int_to_fp (int32_t n) +{ + return { n * CONVERSION_CONST }; +} /* Handles conversion of fixed point to integer. First version truncates, second one rounds */ -#define FLOOR_FP_TO_INT(x) ((x) / (CONVERSION_CONST)) -#define ROUNDING_FP_TO_INT(x) ((x) >= 0 ? ((x) + ((CONVERSION_CONST) / 2)) : ((x) - ((CONVERSION_CONST) / 2))) +inline int32_t +fp_floor (fp32_t x) +{ + return { x.raw / CONVERSION_CONST }; +} -/* Fixed Point Arithmetic addition operations */ -#define FP_ADD(x, y) ((x) + (y)) -#define FP_SUBTRACT(x, y) ((x) - (y)) -/* Addition and Subtraction but between a fixed point and an integer */ -#define FP_ADD_INT(x, n) ((x) + ((n) * (CONVERSION_CONST))) -#define FP_SUBTRACT_INT(x, n) ((x) - ((n) * (CONVERSION_CONST))) +inline int32_t +fp_round (fp32_t x) +{ + if (x.raw >= 0) + return (x.raw + CONVERSION_CONST / 2) / CONVERSION_CONST; + else + return (x.raw - CONVERSION_CONST / 2) / CONVERSION_CONST; +} -/* Fixed Point Arithmetic multiplication operations */ -#define FP_MULTIPLY(x, y) ((int64_t)(x)) * (y) / (CONVERSION_CONST) -#define FP_DIVIDE(x, y) ((int64_t)(x)) * (CONVERSION_CONST) / (y) -/* Multiplication and division but between a fixed point and an integer */ -#define FP_MULTIPLY_INT(x, n) ((x) * (n)) -#define FP_DIVIDE_INT(x, n) ((x) / (n)) +/* Add two fixed points */ +inline fp32_t +fp_add (fp32_t x, fp32_t y) +{ + return { x.raw + y.raw }; +} + +/* Subtract two fixed points */ +inline fp32_t +fp_sub (fp32_t x, fp32_t y) +{ + return { x.raw - y.raw }; +} + +/* Add fixed point to integer */ +inline fp32_t +fp_add_int (fp32_t x, int32_t n) +{ + return { x.raw + n * CONVERSION_CONST }; +} + +/* Subtract integer from fixed point */ +inline fp32_t +fp_sub_int (fp32_t x, int32_t n) +{ + return { x.raw - n * CONVERSION_CONST }; +} + +/* Multiple two fixed points */ +inline fp32_t +fp_mul (fp32_t x, fp32_t y) +{ + return { ((int64_t)x.raw) * y.raw / CONVERSION_CONST }; +} + +/* Divide two fixed points */ +inline fp32_t +fp_div (fp32_t x, fp32_t y) +{ + return { ((int64_t)x.raw) * CONVERSION_CONST / y.raw }; +} + +/* Multiply fixed point and integer */ +inline fp32_t +fp_mul_int (fp32_t x, int32_t n) +{ + return { x.raw * n }; +} + +/* Divide fixed point by integer */ +inline fp32_t +fp_div_int (fp32_t x, int32_t n) +{ + return { x.raw / n }; +} #endif //FIXED_POINT_H diff --git a/src/threads/thread.c b/src/threads/thread.c index c74d86b..bf65702 100644 --- a/src/threads/thread.c +++ b/src/threads/thread.c @@ -4,6 +4,7 @@ #include #include #include +#include "threads/fixed-point.h" #include "threads/flags.h" #include "threads/interrupt.h" #include "threads/intr-stubs.h" @@ -399,8 +400,7 @@ thread_get_load_avg (void) int thread_get_recent_cpu (void) { - /* Not yet implemented. */ - return 0; + return fp_round (fp_mul_int (thread_current ()->recent_cpu, 100)); } /* Idle thread. Executes when no other thread is ready to run. diff --git a/src/threads/thread.h b/src/threads/thread.h index 3019926..f85b814 100644 --- a/src/threads/thread.h +++ b/src/threads/thread.h @@ -4,6 +4,7 @@ #include #include #include +#include "threads/fixed-point.h" /* States in a thread's life cycle. */ enum thread_status @@ -95,7 +96,7 @@ struct thread /* MLFQS items */ int nice; /* Nice value for this thread */ - int32_t recent_cpu; /* Amount of time this process received */ + fp32_t recent_cpu; /* Amount of time this process received */ #ifdef USERPROG /* Owned by userprog/process.c. */