/*
- * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013, 2014 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include "bitmap.h"
#include "byte-order.h"
#include "coverage.h"
+#include "ovs-rcu.h"
#include "ovs-thread.h"
#include "vlog.h"
#ifdef HAVE_PTHREAD_SET_NAME_NP
/* --version option output. */
static char *program_version;
-/* Buffer used by ovs_strerror(). */
+/* Buffer used by ovs_strerror() and ovs_format_message(). */
DEFINE_STATIC_PER_THREAD_DATA(struct { char s[128]; },
strerror_buffer,
{ "" });
return xrealloc(p, *n * s);
}
+/* The desired minimum alignment for an allocated block of memory. */
+#define MEM_ALIGN MAX(sizeof(void *), 8)
+BUILD_ASSERT_DECL(IS_POW2(MEM_ALIGN));
+BUILD_ASSERT_DECL(CACHE_LINE_SIZE >= MEM_ALIGN);
+
+/* Allocates and returns 'size' bytes of memory in dedicated cache lines. That
+ * is, the memory block returned will not share a cache line with other data,
+ * avoiding "false sharing". (The memory returned will not be at the start of
+ * a cache line, though, so don't assume such alignment.)
+ *
+ * Use free_cacheline() to free the returned memory block. */
+void *
+xmalloc_cacheline(size_t size)
+{
+ void **payload;
+ void *base;
+
+ /* Allocate room for:
+ *
+ * - Up to CACHE_LINE_SIZE - 1 bytes before the payload, so that the
+ * start of the payload doesn't potentially share a cache line.
+ *
+ * - A payload consisting of a void *, followed by padding out to
+ * MEM_ALIGN bytes, followed by 'size' bytes of user data.
+ *
+ * - Space following the payload up to the end of the cache line, so
+ * that the end of the payload doesn't potentially share a cache line
+ * with some following block. */
+ base = xmalloc((CACHE_LINE_SIZE - 1)
+ + ROUND_UP(MEM_ALIGN + size, CACHE_LINE_SIZE));
+
+ /* Locate the payload and store a pointer to the base at the beginning. */
+ payload = (void **) ROUND_UP((uintptr_t) base, CACHE_LINE_SIZE);
+ *payload = base;
+
+ return (char *) payload + MEM_ALIGN;
+}
+
+/* Like xmalloc_cacheline() but clears the allocated memory to all zero
+ * bytes. */
+void *
+xzalloc_cacheline(size_t size)
+{
+ void *p = xmalloc_cacheline(size);
+ memset(p, 0, size);
+ return p;
+}
+
+/* Frees a memory block allocated with xmalloc_cacheline() or
+ * xzalloc_cacheline(). */
+void
+free_cacheline(void *p)
+{
+ if (p) {
+ free(*(void **) ((uintptr_t) p - MEM_ALIGN));
+ }
+}
+
char *
xasprintf(const char *format, ...)
{
size_t size;
/* Get maximum path length or at least a reasonable estimate. */
+#ifndef _WIN32
path_max = pathconf(".", _PC_PATH_MAX);
+#else
+ path_max = MAX_PATH;
+#endif
size = (path_max < 0 ? 1024
: path_max > 10240 ? 10240
: path_max);
return ok;
}
+void
+xsleep(unsigned int seconds)
+{
+ ovsrcu_quiesce_start();
+#ifdef _WIN32
+ Sleep(seconds * 1000);
+#else
+ sleep(seconds);
+#endif
+ ovsrcu_quiesce_end();
+}
+
#ifdef _WIN32
\f
-/* Calls FormatMessage() with GetLastError() as an argument. Returns
- * pointer to a buffer that receives the null-terminated string that specifies
- * the formatted message and that has to be freed by the caller with
- * LocalFree(). */
char *
-ovs_lasterror_to_string(void)
+ovs_format_message(int error)
{
- char *buffer;
- FormatMessage(FORMAT_MESSAGE_ALLOCATE_BUFFER | FORMAT_MESSAGE_FROM_SYSTEM
- | FORMAT_MESSAGE_IGNORE_INSERTS, NULL, GetLastError(), 0,
- (char *)&buffer, 0, NULL);
+ enum { BUFSIZE = sizeof strerror_buffer_get()->s };
+ char *buffer = strerror_buffer_get()->s;
+
+ FormatMessage(FORMAT_MESSAGE_FROM_SYSTEM | FORMAT_MESSAGE_IGNORE_INSERTS,
+ NULL, error, 0, buffer, BUFSIZE, NULL);
return buffer;
}
+
+/* Returns a null-terminated string that explains the last error.
+ * Use this function to get the error string for WINAPI calls. */
+char *
+ovs_lasterror_to_string(void)
+{
+ return ovs_format_message(GetLastError());
+}
+
+int
+ftruncate(int fd, off_t length)
+{
+ int error;
+
+ error = _chsize_s(fd, length);
+ if (error) {
+ return -1;
+ }
+ return 0;
+}
#endif