"I am a person who works hard and plays hard."

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Yuan Wei
Second Year Graduate Student Department of Computer Science
University of Virginia Charlottesville, VA 22903
Email: yw3f@cs.virginia.edu

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Source Code Analysis
         

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memory.c File Reference

#include <stdio.h>
#include <stdlib.h>
#include "host.h"
#include "misc.h"
#include "machine.h"
#include "options.h"
#include "stats.h"
#include "memory.h"

Include dependency graph for memory.c:

Go to the source code of this file.

Functions

• mem_t * mem_create (char *name)
• byte_t * mem_translate (struct mem_t *mem, md_addr_t addr)
• void mem_newpage (struct mem_t *mem, md_addr_t addr)
• enum md_fault_type mem_access (struct mem_t *mem, enum mem_cmd cmd, md_addr_t addr, void *vp, int nbytes)
• void mem_reg_stats (struct mem_t *mem, struct stat_sdb_t *sdb)
• void mem_init (struct mem_t *mem)
• enum md_fault_type mem_dump (struct mem_t *mem, md_addr_t addr, int len, FILE *stream)
• enum md_fault_type mem_strcpy (mem_access_fn mem_fn, struct mem_t *mem, enum mem_cmd cmd, md_addr_t addr, char *s)
• enum md_fault_type mem_bcopy (mem_access_fn mem_fn, struct mem_t *mem, enum mem_cmd cmd, md_addr_t addr, void *vp, int nbytes)
• enum md_fault_type mem_bcopy4 (mem_access_fn mem_fn, struct mem_t *mem, enum mem_cmd cmd, md_addr_t addr, void *vp, int nbytes)
• enum md_fault_type mem_bzero (mem_access_fn mem_fn, struct mem_t *mem, md_addr_t addr, int nbytes)

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Function Documentation

enum md_fault_type mem_access (  struct mem_t *    mem, enum mem_cmd    cmd, md_addr_t    addr, void *    vp, int    nbytes )

Definition at line 182 of file memory.c. References byte_t, half_t, mem_cmd, MEM_READ_BYTE, MEM_READ_HALF, MEM_READ_WORD, MEM_WRITE_BYTE, MEM_WRITE_HALF, MEM_WRITE_WORD, Read, and word_t. Referenced by cheetah_access_fn(), dcache_access_fn(), dlite_mem_obj(), ld_load_prog(), mem_dump(), and simoo_mem_obj(). { byte_t *p = vp; /* check alignments */ if (/* check size */(nbytes & (nbytes-1)) != 0 || /* check max size */nbytes > MD_PAGE_SIZE) return md_fault_access; if (/* check natural alignment */(addr & (nbytes-1)) != 0) return md_fault_alignment; /* perform the copy */ { if (cmd == Read) { while (nbytes-- > 0) { *((byte_t *)p) = MEM_READ_BYTE(mem, addr); p += sizeof(byte_t); addr += sizeof(byte_t); } } else { while (nbytes-- > 0) { MEM_WRITE_BYTE(mem, addr, *((byte_t *)p)); p += sizeof(byte_t); addr += sizeof(byte_t); } } } #if 0 switch (nbytes) { case 1: if (cmd == Read) *((byte_t *)p) = MEM_READ_BYTE(mem, addr); else MEM_WRITE_BYTE(mem, addr, *((byte_t *)p)); break; case 2: if (cmd == Read) *((half_t *)p) = MEM_READ_HALF(mem, addr); else MEM_WRITE_HALF(mem, addr, *((half_t *)p)); break; case 4: if (cmd == Read) *((word_t *)p) = MEM_READ_WORD(mem, addr); else MEM_WRITE_WORD(mem, addr, *((word_t *)p)); break; #ifdef HOST_HAS_QWORD case 8: if (cmd == Read) *((qword_t *)p) = MEM_READ_QWORD(mem, addr); else MEM_WRITE_QWORD(mem, addr, *((qword_t *)p)); break; #endif /* HOST_HAS_QWORD */ default: break; } #endif /* no fault... */ return md_fault_none; }

enum md_fault_type mem_bcopy (  mem_access_fn    mem_fn, struct mem_t *    mem, enum mem_cmd    cmd, md_addr_t    addr, void *    vp, int    nbytes )

Definition at line 382 of file memory.c. References byte_t, mem_access_fn, and mem_cmd. Referenced by ld_load_prog(), and sys_syscall(). { byte_t *p = vp; enum md_fault_type fault; /* copy NBYTES bytes to/from simulator memory */ while (nbytes-- > 0) { fault = mem_fn(mem, cmd, addr++, p++, 1); if (fault != md_fault_none) return fault; } /* no faults... */ return md_fault_none; }

enum md_fault_type mem_bcopy4 (  mem_access_fn    mem_fn, struct mem_t *    mem, enum mem_cmd    cmd, md_addr_t    addr, void *    vp, int    nbytes )

Definition at line 408 of file memory.c. References byte_t, mem_access_fn, mem_cmd, and word_t. { byte_t *p = vp; int words = nbytes >> 2; /* note: nbytes % 2 == 0 is assumed */ enum md_fault_type fault; while (words-- > 0) { fault = mem_fn(mem, cmd, addr, p, sizeof(word_t)); if (fault != md_fault_none) return fault; addr += sizeof(word_t); p += sizeof(word_t); } /* no faults... */ return md_fault_none; }

enum md_fault_type mem_bzero (  mem_access_fn    mem_fn, struct mem_t *    mem, md_addr_t    addr, int    nbytes )

Definition at line 435 of file memory.c. References byte_t, mem_access_fn, and Write. Referenced by ld_load_prog(). { byte_t c = 0; enum md_fault_type fault; /* zero out NBYTES of simulator memory */ while (nbytes-- > 0) { fault = mem_fn(mem, Write, addr++, &c, 1); if (fault != md_fault_none) return fault; } /* no faults... */ return md_fault_none; }

struct mem_t* mem_create (  char *    name )

Definition at line 106 of file memory.c. References fatal(), mystrdup(), and mem_t::name. Referenced by sim_init(), and sim_load_prog(). { struct mem_t *mem; mem = calloc(1, sizeof(struct mem_t)); if (!mem) fatal("out of virtual memory"); mem->name = mystrdup(name); return mem; }

enum md_fault_type mem_dump (  struct mem_t *    mem, md_addr_t    addr, int    len, FILE *    stream )

Definition at line 308 of file memory.c. References len, mem_access(), myfprintf(), Read, and word_t. { int data; enum md_fault_type fault; if (!stream) stream = stderr; addr &= ~sizeof(word_t); len = (len + (sizeof(word_t) - 1)) & ~sizeof(word_t); while (len-- > 0) { fault = mem_access(mem, Read, addr, &data, sizeof(word_t)); if (fault != md_fault_none) return fault; myfprintf(stream, "0x%08p: %08x\n", addr, data); addr += sizeof(word_t); } /* no faults... */ return md_fault_none; }

void mem_init (  struct mem_t *    mem )

Definition at line 293 of file memory.c. References MEM_PTAB_SIZE, mem_t::page_count, mem_t::ptab, mem_t::ptab_accesses, and mem_t::ptab_misses. Referenced by sim_init(). { int i; /* initialize the first level page table to all empty */ for (i=0; i < MEM_PTAB_SIZE; i++) mem->ptab[i] = NULL; mem->page_count = 0; mem->ptab_misses = 0; mem->ptab_accesses = 0; }

void mem_newpage (  struct mem_t *    mem, md_addr_t    addr )

Definition at line 152 of file memory.c. References byte_t, fatal(), getcore(), MEM_PTAB_SET, MEM_PTAB_TAG, mem_pte_t::next, mem_pte_t::page, mem_t::page_count, mem_t::ptab, and mem_pte_t::tag. { byte_t *page; struct mem_pte_t *pte; /* see misc.c for details on the getcore() function */ page = getcore(MD_PAGE_SIZE); if (!page) fatal("out of virtual memory"); /* generate a new PTE */ pte = calloc(1, sizeof(struct mem_pte_t)); if (!pte) fatal("out of virtual memory"); pte->tag = MEM_PTAB_TAG(addr); pte->page = page; /* insert PTE into inverted hash table */ pte->next = mem->ptab[MEM_PTAB_SET(addr)]; mem->ptab[MEM_PTAB_SET(addr)] = pte; /* one more page allocated */ mem->page_count++; }

void mem_reg_stats (  struct mem_t *    mem, struct stat_sdb_t *    sdb )

Definition at line 264 of file memory.c. References mem_t::name, mem_t::page_count, mem_t::ptab_accesses, mem_t::ptab_misses, stat_reg_counter, and stat_reg_formula(). Referenced by sim_reg_stats(). { char buf[512], buf1[512]; sprintf(buf, "%s.page_count", mem->name); stat_reg_counter(sdb, buf, "total number of pages allocated", &mem->page_count, mem->page_count, NULL); sprintf(buf, "%s.page_mem", mem->name); sprintf(buf1, "%s.page_count * %d / 1024", mem->name, MD_PAGE_SIZE); stat_reg_formula(sdb, buf, "total size of memory pages allocated", buf1, "%11.0fk"); sprintf(buf, "%s.ptab_misses", mem->name); stat_reg_counter(sdb, buf, "total first level page table misses", &mem->ptab_misses, mem->ptab_misses, NULL); sprintf(buf, "%s.ptab_accesses", mem->name); stat_reg_counter(sdb, buf, "total page table accesses", &mem->ptab_accesses, mem->ptab_accesses, NULL); sprintf(buf, "%s.ptab_miss_rate", mem->name); sprintf(buf1, "%s.ptab_misses / %s.ptab_accesses", mem->name, mem->name); stat_reg_formula(sdb, buf, "first level page table miss rate", buf1, NULL); }

enum md_fault_type mem_strcpy (  mem_access_fn    mem_fn, struct mem_t *    mem, enum mem_cmd    cmd, md_addr_t    addr, char *    s )

Definition at line 338 of file memory.c. References mem_access_fn, mem_cmd, Read, s, and Write. Referenced by ld_load_prog(), and sys_syscall(). { int n = 0; char c; enum md_fault_type fault; switch (cmd) { case Read: /* copy until string terminator ('\0') is encountered */ do { fault = mem_fn(mem, Read, addr++, &c, 1); if (fault != md_fault_none) return fault; *s++ = c; n++; } while (c); break; case Write: /* copy until string terminator ('\0') is encountered */ do { c = *s++; fault = mem_fn(mem, Write, addr++, &c, 1); if (fault != md_fault_none) return fault; n++; } while (c); break; default: return md_fault_internal; } /* no faults... */ return md_fault_none; }

byte_t* mem_translate (  struct mem_t *    mem, md_addr_t    addr )

Definition at line 120 of file memory.c. References MEM_PTAB_SET, MEM_PTAB_TAG, mem_pte_t::next, mem_pte_t::page, mem_t::ptab, mem_t::ptab_accesses, mem_t::ptab_misses, and mem_pte_t::tag. { struct mem_pte_t *pte, *prev; /* got here via a first level miss in the page tables */ mem->ptab_misses++; mem->ptab_accesses++; /* locate accessed PTE */ for (prev=NULL, pte=mem->ptab[MEM_PTAB_SET(addr)]; pte != NULL; prev=pte, pte=pte->next) { if (pte->tag == MEM_PTAB_TAG(addr)) { /* move this PTE to head of the bucket list */ if (prev) { prev->next = pte->next; pte->next = mem->ptab[MEM_PTAB_SET(addr)]; mem->ptab[MEM_PTAB_SET(addr)] = pte; } return pte->page; } } /* no translation found, return NULL */ return NULL; }

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