Merge branch 'old-types' into scale-amd64

32a3900d · Silas Boyd-Wickizer · 2db6c3ef · 87942b7c · 32a3900d · 32a3900d
--- a/bin/dirbench.cc
+++ b/bin/dirbench.cc
@@ -69,7 +69,7 @@ main(int ac, char** av)
  mkdir("/dbx");
-  mtenable("xv6-schedbench");
+  mtenable("xv6-dirbench");
  u64 t0 = rdtsc();
  for(u32 i = 0; i < nthread; i++) {
    int pid = fork(0);
@@ -82,7 +82,7 @@ main(int ac, char** av)
  for (u32 i = 0; i < nthread; i++)
    wait();
  u64 t1 = rdtsc();
-  mtdisable("xv6-schedbench");
+  mtdisable("xv6-dirbench");
  printf("dirbench: %lu\n", t1-t0);
  return 0;

--- a/bin/filebench.cc
+++ b/bin/filebench.cc
@@ -7,12 +7,15 @@
 #define xfork() fork()
 #define xexit() exit(EXIT_SUCCESS)
 #define xcreat(name) open((name), O_CREATE|O_WRONLY, S_IRUSR|S_IWUSR)
+#define mtenable(x) do { } while(0)
+#define mtdisable(x) do { } while(0)
 typedef uint64_t u64;
 #else
 #include "types.h"
 #include "user.h"
 #include "fcntl.h"
 #include "amd64.h"
+#include "mtrace.h"
 #define xfork() fork(0)
 #define xexit() exit()
 #define xcreat(name) open((name), O_CREATE|O_WRONLY)
@@ -78,6 +81,7 @@ main(int ac, char **av)
  }
  close(fd);
+  mtenable("xv6-filebench");
  u64 t0 = rdtsc();
  for (int i = 0; i < nthread; i++) {
    int pid = xfork();
@@ -90,6 +94,7 @@ main(int ac, char **av)
  for (int i = 0; i < nthread; i++)
    wait();
  u64 t1 = rdtsc();
+  mtdisable("xv6-filebench");
  printf("filebench: %lu\n", t1-t0);
  return 0;

--- a/include/file.hh
+++ b/include/file.hh
@@ -68,7 +68,7 @@ struct inode : public referenced, public rcu_freed
  short major;
  short minor;
  u32 size;
-  u32 addrs[NDIRECT+1];
+  std::atomic<u32> addrs[NDIRECT+1];
 private:
  inode();

--- a/kernel/file.cc
+++ b/kernel/file.cc
@@ -91,11 +91,9 @@ file::pread(char *addr, size_t n, off_t off)
 {
  if(type == file::FD_INODE){
    int r;
-    ilock(ip, 0);
    if(ip->type == 0)
      panic("file::pread");
    r = readi(ip, addr, off, n);
-    iunlock(ip);
    return r;
  }
  return -1;

--- a/kernel/fs.cc
+++ b/kernel/fs.cc
@@ -516,16 +516,28 @@ bmap(struct inode *ip, u32 bn)
  struct buf *bp;
  if(bn < NDIRECT){
-    if((addr = ip->addrs[bn]) == 0)
+  retry0:
-      ip->addrs[bn] = addr = balloc(ip->dev);
+    if((addr = ip->addrs[bn]) == 0) {
+      addr = balloc(ip->dev);
+      if (!cmpxch(&ip->addrs[bn], (u32)0, addr)) {
+        bfree(ip->dev, addr);
+        goto retry0;
+      }
+    }
    return addr;
  }
  bn -= NDIRECT;
  if(bn < NINDIRECT){
    // Load indirect block, allocating if necessary.
-    if((addr = ip->addrs[NDIRECT]) == 0)
+  retry1:
-      ip->addrs[NDIRECT] = addr = balloc(ip->dev);
+    if((addr = ip->addrs[NDIRECT]) == 0) {
+      addr = balloc(ip->dev);
+      if (!cmpxch(&ip->addrs[NDIRECT], (u32)0, addr)) {
+        bfree(ip->dev, addr);
+        goto retry1;
+      }
+    }
    int writerflag = 0;
    bp = bread(ip->dev, addr, writerflag);

--- a/kernel/sysfile.cc
+++ b/kernel/sysfile.cc
@@ -62,16 +62,27 @@ ssize_t
 sys_pread(int fd, void *ubuf, size_t count, off_t offset)
 {
  sref<file> f;
-  uptr i = (uptr)ubuf;
  if (!getfile(fd, &f))
    return -1;
-  for(uptr va = PGROUNDDOWN(i); va < i+count; va = va + PGSIZE)
+  if (count < PGSIZE) {
-    if(pagefault(myproc()->vmap, va, 0) < 0)
+    ssize_t r;
-      return -1;
+    char* b;
+    b = kalloc("preadbuf");
-  return f->pread((char*)ubuf, count, offset);
+    r = f->pread(b, count, offset);
+    if (r > 0)
+      putmem(ubuf, b, r);
+    kfree(b);
+    return r;
+  } else {
+    // XXX(sbw) pagefaulting doesn't guarantee ubuf is mapped 
+    // while pread executes
+    uptr i = (uptr)ubuf;
+    for(uptr va = PGROUNDDOWN(i); va < i+count; va = va + PGSIZE)
+      if(pagefault(myproc()->vmap, va, 0) < 0)
+        return -1;
+    return f->pread((char*)ubuf, count, offset);
+  }
 }
 //SYSCALL