chrt: add support for SCHED_IDLE

Signed-off-by: Povilas Kanapickas <povilas@radix.lt>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/util-linux/chrt.c b/util-linux/chrt.c
index e7abd4f5a91fff155a3eb548851004e6bb77d0db..bbd6e2deb7a72bf770c8fab4ee8708f4ed3d1dc8 100644 (file)
--- a/util-linux/chrt.c
+++ b/util-linux/chrt.c
@@ -17,7 +17,7 @@
 //kbuild:lib-$(CONFIG_CHRT) += chrt.o
 
 //usage:#define chrt_trivial_usage
-//usage:       "[-prfomb] [PRIO] [PID | PROG ARGS]"
+//usage:       "[-prfombi] [PRIO] [PID | PROG ARGS]"
 //usage:#define chrt_full_usage "\n\n"
 //usage:       "Change scheduling priority and class for a process\n"
 //usage:     "\n       -p      Operate on PID"
@@ -25,6 +25,7 @@
 //usage:     "\n       -f      Set SCHED_FIFO class"
 //usage:     "\n       -o      Set SCHED_OTHER class"
 //usage:     "\n       -b      Set SCHED_BATCH class"
+//usage:     "\n       -i      Set SCHED_IDLE class"
 //usage:     "\n       -m      Show min/max priorities"
 //usage:
 //usage:#define chrt_example_usage
@@ -42,12 +43,11 @@ static const struct {
        {SCHED_OTHER, "SCHED_OTHER"},
        {SCHED_FIFO, "SCHED_FIFO"},
        {SCHED_RR, "SCHED_RR"},
-       {SCHED_BATCH, "SCHED_BATCH"}
+       {SCHED_BATCH, "SCHED_BATCH"},
+       {0 /* unused */, ""},
+       {SCHED_IDLE, "SCHED_IDLE"}
 };
 
-//TODO: add
-// -i, SCHED_IDLE
-
 static void show_min_max(int pol)
 {
        const char *fmt = "%s min/max priority\t: %u/%u\n";
@@ -66,6 +66,7 @@ static void show_min_max(int pol)
 #define OPT_f (1<<3)
 #define OPT_o (1<<4)
 #define OPT_b (1<<5)
+#define OPT_i (1<<6)
 
 int chrt_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int chrt_main(int argc UNUSED_PARAM, char **argv)
@@ -79,12 +80,13 @@ int chrt_main(int argc UNUSED_PARAM, char **argv)
        int policy = SCHED_RR;
 
        /* only one policy accepted */
-       opt = getopt32(argv, "^+" "mprfob" "\0" "r--fob:f--rob:o--rfb:b--rfo");
+       opt = getopt32(argv, "^+" "mprfobi" "\0" "r--fobi:f--robi:o--rfbi:b--rfoi:i--rfob");
        if (opt & OPT_m) { /* print min/max and exit */
                show_min_max(SCHED_FIFO);
                show_min_max(SCHED_RR);
                show_min_max(SCHED_OTHER);
                show_min_max(SCHED_BATCH);
+               show_min_max(SCHED_IDLE);
                fflush_stdout_and_exit(EXIT_SUCCESS);
        }
        if (opt & OPT_r)
@@ -95,6 +97,8 @@ int chrt_main(int argc UNUSED_PARAM, char **argv)
                policy = SCHED_OTHER;
        if (opt & OPT_b)
                policy = SCHED_BATCH;
+       if (opt & OPT_i)
+               policy = SCHED_IDLE;
 
        argv += optind;
        if (!argv[0])
@@ -138,11 +142,12 @@ int chrt_main(int argc UNUSED_PARAM, char **argv)
 
        /* from the manpage of sched_getscheduler:
        [...] sched_priority can have a value in the range 0 to 99.
-       [...] SCHED_OTHER or SCHED_BATCH must be assigned static priority 0.
+       [...] SCHED_OTHER, SCHED_BATCH or SCHED_IDLE must be assigned static
+                 priority 0.
        [...] SCHED_FIFO or SCHED_RR can have static priority in 1..99 range.
        */
        sp.sched_priority = xstrtou_range(priority, 0,
-                       (policy != SCHED_OTHER && policy != SCHED_BATCH) ? 1 : 0, 99);
+                       (policy != SCHED_OTHER && policy != SCHED_BATCH && policy != SCHED_IDLE) ? 1 : 0, 99);
 
        if (sched_setscheduler(pid, policy, &sp) < 0)
                bb_perror_msg_and_die("can't %cet pid %d's policy", 's', (int)pid);