Cleaup chrt
diff --git a/lib/lib.c b/lib/lib.c
index ceced26..b6277f3 100644
--- a/lib/lib.c
+++ b/lib/lib.c
@@ -512,6 +512,16 @@
nanosleep(&ts, &ts);
}
+// return 1<<x of highest bit set
+int highest_bit(unsigned long l)
+{
+ int i;
+
+ for (i = 0; l; i++) l >>= 1;
+
+ return i-1;
+}
+
// Inefficient, but deals with unaligned access
int64_t peek_le(void *ptr, unsigned size)
{
diff --git a/lib/lib.h b/lib/lib.h
index efdc1fa..5d2bb4d 100644
--- a/lib/lib.h
+++ b/lib/lib.h
@@ -192,6 +192,7 @@
char *readfileat(int dirfd, char *name, char *buf, off_t *len);
char *readfile(char *name, char *buf, off_t len);
void msleep(long miliseconds);
+int highest_bit(unsigned long l);
int64_t peek_le(void *ptr, unsigned size);
int64_t peek_be(void *ptr, unsigned size);
int64_t peek(void *ptr, unsigned size);
diff --git a/lib/portability.h b/lib/portability.h
index 01c77c6..e62de13 100644
--- a/lib/portability.h
+++ b/lib/portability.h
@@ -45,9 +45,13 @@
#define RLIMIT_RTTIME 15
#endif
+// Introduced in Linux 3.1
#ifndef SEEK_DATA
#define SEEK_DATA 3
#endif
+#ifndef SEEK_HOLE
+#define SEEK_HOLE 4
+#endif
// We don't define GNU_dammit because we're not part of the gnu project, and
// don't want to get any FSF on us. Unfortunately glibc (gnu libc)
@@ -199,18 +203,18 @@
#ifndef O_NOFOLLOW
#define O_NOFOLLOW 0
#endif
-
#ifndef O_NOATIME
#define O_NOATIME 01000000
#endif
-
#ifndef O_CLOEXEC
#define O_CLOEXEC 02000000
#endif
-
#ifndef O_PATH
#define O_PATH 010000000
#endif
+#ifndef SCHED_RESET_ON_FORK
+#define SCHED_RESET_ON_FORK (1<<30)
+#endif
// Glibc won't give you linux-kernel constants unless you say "no, a BUD lite"
// even though linux has nothing to do with the FSF and never has.
diff --git a/toys/pending/chrt.c b/toys/pending/chrt.c
index d2b73a4..01076b9 100644
--- a/toys/pending/chrt.c
+++ b/toys/pending/chrt.c
@@ -1,92 +1,81 @@
/* chrt.c - Get/set real-time (scheduling) attributes
*
* Copyright 2016 The Android Open Source Project
+ *
+ * Note: -ibrfo flags sorted to match SCHED positions for highest_bit()
-USE_CHRT(NEWTOY(chrt, "mp#bfiorR[!bfior]", TOYFLAG_USR|TOYFLAG_SBIN))
+USE_CHRT(NEWTOY(chrt, "^mp#<0iRbrfo[!ibrfo]", TOYFLAG_USR|TOYFLAG_SBIN))
config CHRT
bool "chrt"
default n
help
- usage: chrt [-m] [-p PID] [POLICY PRIO] [COMMAND [ARGS...]]
+ usage: chrt [-Rmofrbi] {-p PID [PRIORITY] | [PRIORITY COMMAND...]}
- Get/set a process' real-time (scheduling) attributes.
+ Get/set a process' real-time scheduling policy and priority.
- -p Apply to given pid
+ -p Set/query given pid (instead of running COMMAND)
-R Set SCHED_RESET_ON_FORK
-m Show min/max priorities available
- Policies:
- -b SCHED_BATCH -f SCHED_FIFO -i SCHED_IDLE
- -o SCHED_OTHER -r SCHED_RR
+ Set policy (default -r):
+
+ -o SCHED_OTHER -f SCHED_FIFO -r SCHED_RR
+ -b SCHED_BATCH -i SCHED_IDLE
*/
#define FOR_chrt
#include "toys.h"
-#include <linux/sched.h>
-
GLOBALS(
long pid;
)
-static char *policy_name(int policy) {
- char *policy_names[] = { "SCHED_OTHER", "SCHED_FIFO", "SCHED_RR",
- "SCHED_BATCH", "4", "SCHED_IDLE", "SCHED_DEADLINE" };
-
- return policy < ARRAY_LEN(policy_names) ? policy_names[policy] : "???";
-}
+char *polnames[] = {
+ "SCHED_OTHER", "SCHED_FIFO", "SCHED_RR", "SCHED_BATCH", 0, "SCHED_IDLE",
+ "SCHED_DEADLINE"
+};
void chrt_main(void)
{
- int policy = SCHED_RR;
- struct sched_param p;
+ int pol, pri;
// Show min/maxes?
if (toys.optflags&FLAG_m) {
- for (policy = SCHED_OTHER; policy <= SCHED_IDLE; ++policy)
- if (policy != 4) // There's an unused hole in the priorities.
- printf("%s min/max priority\t: %d/%d\n", policy_name(policy),
- sched_get_priority_min(policy), sched_get_priority_max(policy));
- return;
- }
-
- // If we have a pid but no command or policy, we're just querying.
- if (TT.pid && !*(toys.optargs+1) &&
- !(toys.optflags&(FLAG_b|FLAG_f|FLAG_i|FLAG_o|FLAG_r))) {
- policy = sched_getscheduler(TT.pid);
- if (policy == -1) perror_exit("sched_getscheduler");
- policy &= ~SCHED_RESET_ON_FORK;
- printf("pid %ld's current scheduling policy: %s\n",
- TT.pid, policy_name(policy));
-
- if (sched_getparam(TT.pid, &p)) perror_exit("sched_getparam");
- printf("pid %ld's current scheduling priority: %d\n",
- TT.pid, p.sched_priority);
+ for (pol = 0; pol<ARRAY_LEN(polnames); pol++) if (polnames[pol])
+ printf("%s min/max priority\t: %d/%d\n", polnames[pol],
+ sched_get_priority_min(pol), sched_get_priority_max(pol));
return;
}
- // Did we get a meaningful combination of arguments?
- if (!*toys.optargs) help_exit("missing priority");
- if (TT.pid && *(toys.optargs+1)) help_exit("-p and command");
- if (!TT.pid && !*(toys.optargs+1)) help_exit("missing command");
+ // Query when -p without priority.
+ if (toys.optflags==FLAG_p && !*toys.optargs) {
+ char *s = "???", *R = "";
- // Translate into policy and priority.
- if (toys.optflags&FLAG_b) policy = SCHED_BATCH;
- else if (toys.optflags&FLAG_f) policy = SCHED_FIFO;
- else if (toys.optflags&FLAG_i) policy = SCHED_IDLE;
- else if (toys.optflags&FLAG_o) policy = SCHED_OTHER;
+ if (-1==(pol = sched_getscheduler(TT.pid))) perror_exit("pid %ld", TT.pid);
+ if (pol & SCHED_RESET_ON_FORK) R = "|SCHED_RESET_ON_FORK";
+ if ((pol &= ~SCHED_RESET_ON_FORK)<ARRAY_LEN(polnames)) s = polnames[pol];
+ printf("pid %ld's current scheduling policy: %s%s\n", TT.pid, s, R);
- if (toys.optflags&FLAG_R) policy |= SCHED_RESET_ON_FORK;
+ if (sched_getparam(TT.pid, (void *)&pri)) perror_exit("sched_getparam");
+ printf("pid %ld's current scheduling priority: %d\n", TT.pid, pri);
- p.sched_priority = atolx_range(*toys.optargs, sched_get_priority_min(policy),
- sched_get_priority_max(policy));
-
- if (sched_setscheduler(TT.pid, policy, &p)) perror_exit("sched_setscheduler");
-
- if (*(toys.optargs+1)) {
- toys.stacktop = 0;
- xexec(++toys.optargs);
+ return;
}
+
+ if (!*toys.optargs) help_exit("no PRIORITY");
+ if (!toys.optargs[1] == !(toys.optflags&FLAG_p))
+ help_exit("need 1 of -p or COMMAND");
+
+ // Set policy and priority
+ if (-1==(pol = highest_bit(toys.optflags&0x2f))) pol = SCHED_RR;
+ pri = atolx_range(*toys.optargs, sched_get_priority_min(pol),
+ sched_get_priority_max(pol));
+ if (toys.optflags&FLAG_R) pol |= SCHED_RESET_ON_FORK;
+
+ if (sched_setscheduler(TT.pid, pol, (void *)&pri))
+ perror_exit("sched_setscheduler");
+
+ if (*(toys.optargs+1)) xexec(++toys.optargs);
}
