system: Add support for getting/setting i/o priorities and include a userspace tool

Signed-off-by: San Mehat <san@google.com>

1 files changed, 57 insertions, 0 deletions

diff --git a/toolbox/ionice.c b/toolbox/ionice.c
new file mode 100644
index 0000000..4a182f2
--- /dev/null
+++ b/toolbox/ionice.c
@@ -0,0 +1,57 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <errno.h>
+
+#include <cutils/iosched_policy.h>
+
+static char *classes[] = {"none", "rt", "be", "idle", NULL};
+
+int ionice_main(int argc, char *argv[])
+{
+    IoSchedClass clazz = IoSchedClass_NONE;
+    int ioprio = 0;
+    int pid;
+
+    if(argc != 2 && argc != 4) {
+        fprintf(stderr, "usage: ionice <pid> [none|rt|be|idle] [prio]\n");
+        return 1;
+    }
+
+    if (!(pid = atoi(argv[1]))) {
+        fprintf(stderr, "Invalid pid specified\n");
+        return 1;
+    }
+
+    if (argc == 2) {
+        if (android_get_ioprio(pid, &clazz, &ioprio)) {
+            fprintf(stderr, "Failed to read priority (%s)\n", strerror(errno));
+            return 1;
+        }
+        fprintf(stdout, "Pid %d, class %s (%d), prio %d\n", pid, classes[clazz], clazz, ioprio);
+        return 0;
+    }
+
+    if (!strcmp(argv[2], "none")) {
+        clazz = IoSchedClass_NONE;
+    } else if (!strcmp(argv[2], "rt")) {
+        clazz = IoSchedClass_RT;
+    } else if (!strcmp(argv[2], "be")) {
+        clazz = IoSchedClass_BE;
+    } else if (!strcmp(argv[2], "idle")) {
+        clazz = IoSchedClass_IDLE;
+    } else {
+        fprintf(stderr, "Unsupported class '%s'\n", argv[2]);
+        return 1;
+    }
+
+    ioprio = atoi(argv[3]);
+
+    printf("Setting pid %d i/o class to %d, prio %d\n", pid, clazz, ioprio);
+    if (android_set_ioprio(pid, clazz, ioprio)) {
+        fprintf(stderr, "Failed to set priority (%s)\n", strerror(errno));
+        return 1;
+    }
+
+    return 0;
+}