1 files changed, 120 insertions, 0 deletions
diff --git a/tests/ebpf/sync_tester.c b/tests/ebpf/sync_tester.c
new file mode 100644
index 000000000..373c85c6d
--- /dev/null
+++ b/tests/ebpf/sync_tester.c
@@ -0,0 +1,120 @@
+#include <errno.h>
+#include <string.h>
+#include <stdio.h>
+#include <sys/stat.h>
+#include <sys/types.h>
+#include <sys/mman.h>
+#include <sys/types.h>
+
+#define _GNU_SOURCE         /* See feature_test_macros(7) */
+#define __USE_GNU
+#include <fcntl.h>
+#include <unistd.h>
+
+void test_sync_file_range(char *output, char *text, size_t length)
+{
+    int fd = open (output, O_WRONLY | O_CREAT | O_APPEND, 0660);
+    if (fd < 0 ) {
+        perror("Cannot get page size");
+        return;
+    }
+
+    int i;
+    size_t offset = 0;
+    for ( i = 0 ; i < 10000; i++ )  {
+        write(fd, text, length);
+        sync_file_range(fd, offset, length, SYNC_FILE_RANGE_WRITE);
+        offset += length;
+    }
+
+    close(fd);
+    sleep(5);
+}
+
+// test based on IBM example https://www.ibm.com/support/knowledgecenter/en/ssw_ibm_i_71/apis/msync.htm
+void test_msync(char *output, char *text, size_t length)
+{
+    int pagesize = sysconf(_SC_PAGE_SIZE);
+    if (pagesize < 0) {
+        perror("Cannot get page size");
+        return;
+    }
+
+    int fd = open(output, (O_CREAT | O_TRUNC | O_RDWR), (S_IRWXU | S_IRWXG | S_IRWXO));
+    if (fd < 0 ) {
+        perror("Cannot open file");
+        return;
+    }
+
+    off_t lastoffset = lseek( fd, pagesize, SEEK_SET);
+    ssize_t written = write(fd, " ", 1);
+    if ( written != 1 ) {
+        perror("Write error. ");
+        close(fd);
+        return;
+    }
+
+    off_t my_offset = 0;
+    void *address = mmap(NULL, pagesize, PROT_WRITE, MAP_SHARED, fd, my_offset);
+
+    if ( address == MAP_FAILED ) {
+        perror("Map error. ");
+        close(fd);
+        return;
+    }
+
+    (void) strcpy( (char*) address, text);
+
+    if ( msync( address, pagesize, MS_SYNC) < 0 ) {
+        perror("msync failed with error:");
+    }
+
+    close(fd);
+    sleep(5);
+}
+
+void test_synchronization(char *output, char *text, size_t length, int (*fcnt)(int))
+{
+    int fd = open (output, O_WRONLY | O_CREAT | O_APPEND, 0660);
+    if (fd < 0 ) {
+        perror("Cannot get page size");
+        return;
+    }
+
+    int i;
+    for ( i = 0 ; i < 10000; i++ ) 
+        write(fd, text, length);
+
+    fcnt(fd);
+    close(fd);
+
+    sleep(5);
+}
+
+void remove_files(char **files) {
+    size_t i = 0;
+    while (files[i])  {
+        unlink(files[i]);
+        i++;
+    }
+}
+
+int main()
+{
+    char *default_text = { "This is a simple example to test a PR. The sleep is used to create different peaks on charts.\n" };
+    char *files[] = { "fsync.txt", "fdatasync.txt", "syncfs.txt", "msync.txt", "sync_file_range.txt", NULL }; 
+    size_t length = strlen(default_text);
+    test_synchronization(files[0], default_text, length, fsync);
+    test_synchronization(files[1], default_text, length, fdatasync);
+    test_synchronization(files[2], default_text, length, syncfs);
+
+    test_msync(files[3], default_text, length);
+
+    test_sync_file_range(files[4], default_text, length);
+
+    sync();
+
+    remove_files(files);
+
+    return 0;
+}