taskset: support CPU masks for more than 64 CPUs

function                                             old     new   delta
taskset_main                                         522     631    +109

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

diff --git a/include/applets.src.h b/include/applets.src.h
index cb36628b50438b98520481198a4ecf9fd04b432f..b80c4f4e842e063c5d1783b67281368f800763d4 100644 (file)
--- a/include/applets.src.h
+++ b/include/applets.src.h
@@ -342,7 +342,6 @@ IF_BB_SYSCTL(APPLET(sysctl, BB_DIR_SBIN, BB_SUID_DROP))
 IF_SYSLOGD(APPLET(syslogd, BB_DIR_SBIN, BB_SUID_DROP))
 IF_TAC(APPLET_NOEXEC(tac, tac, BB_DIR_USR_BIN, BB_SUID_DROP, tac))
 IF_TAIL(APPLET(tail, BB_DIR_USR_BIN, BB_SUID_DROP))
-IF_TASKSET(APPLET(taskset, BB_DIR_USR_BIN, BB_SUID_DROP))
 /* IF_TC(APPLET(tc, BB_DIR_SBIN, BB_SUID_DROP)) */
 IF_TCPSVD(APPLET_ODDNAME(tcpsvd, tcpudpsvd, BB_DIR_USR_BIN, BB_SUID_DROP, tcpsvd))
 IF_TEE(APPLET(tee, BB_DIR_USR_BIN, BB_SUID_DROP))

diff --git a/miscutils/Config.src b/miscutils/Config.src
index 1b2a3ae9a0912880a42181436d17034bc48fc11f..d69abf1a20c4b7e243ae71edd08bd37a369cb8a2 100644 (file)
--- a/miscutils/Config.src
+++ b/miscutils/Config.src
@@ -499,22 +499,6 @@ config STRINGS
          strings prints the printable character sequences for each file
          specified.
 
-config TASKSET
-       bool "taskset"
-       default n  # doesn't build on some non-x86 targets (m68k)
-       help
-         Retrieve or set a processes's CPU affinity.
-         This requires sched_{g,s}etaffinity support in your libc.
-
-config FEATURE_TASKSET_FANCY
-       bool "Fancy output"
-       default y
-       depends on TASKSET
-       help
-         Add code for fancy output. This merely silences a compiler-warning
-         and adds about 135 Bytes. May be needed for machines with alot
-         of CPUs.
-
 config TIME
        bool "time"
        default y

diff --git a/miscutils/Kbuild.src b/miscutils/Kbuild.src
index 8eaa82de99834281bd0f2c5843afa4c11bcbd431..7b449e6e8b587ba6b7f2f68693da9065933cb905 100644 (file)
--- a/miscutils/Kbuild.src
+++ b/miscutils/Kbuild.src
@@ -39,7 +39,6 @@ lib-$(CONFIG_RUNLEVEL)    += runlevel.o
 lib-$(CONFIG_RX)          += rx.o
 lib-$(CONFIG_SETSID)      += setsid.o
 lib-$(CONFIG_STRINGS)     += strings.o
-lib-$(CONFIG_TASKSET)     += taskset.o
 lib-$(CONFIG_TIME)        += time.o
 lib-$(CONFIG_TIMEOUT)     += timeout.o
 lib-$(CONFIG_TTYSIZE)     += ttysize.o

diff --git a/miscutils/taskset.c b/miscutils/taskset.c
index 4a9e3230d3a3e407726793862a9b2adcf78c68f9..8bd32ed61503f43841e30ef78c092a888bed7f03 100644 (file)
--- a/miscutils/taskset.c
+++ b/miscutils/taskset.c
@@ -6,6 +6,25 @@
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
 
+//config:config TASKSET
+//config:      bool "taskset"
+//config:      default n  # doesn't build on some non-x86 targets (m68k)
+//config:      help
+//config:        Retrieve or set a processes's CPU affinity.
+//config:        This requires sched_{g,s}etaffinity support in your libc.
+//config:
+//config:config FEATURE_TASKSET_FANCY
+//config:      bool "Fancy output"
+//config:      default y
+//config:      depends on TASKSET
+//config:      help
+//config:        Add code for fancy output. This merely silences a compiler-warning
+//config:        and adds about 135 Bytes. May be needed for machines with alot
+//config:        of CPUs.
+
+//applet:IF_TASKSET(APPLET(taskset, BB_DIR_USR_BIN, BB_SUID_DROP))
+//kbuild:lib-$(CONFIG_TASKSET) += taskset.o
+
 //usage:#define taskset_trivial_usage
 //usage:       "[-p] [MASK] [PID | PROG ARGS]"
 //usage:#define taskset_full_usage "\n\n"
@@ -22,6 +41,11 @@
 //usage:       "pid 6671's new affinity mask: 1\n"
 //usage:       "$ taskset -p 1\n"
 //usage:       "pid 1's current affinity mask: 3\n"
+/*
+ Not yet implemented:
+ * -a/--all-tasks (affect all threads)
+ * -c/--cpu-list  (specify CPUs via "1,3,5-7")
+ */
 
 #include <sched.h>
 #include "libbb.h"
@@ -128,17 +152,65 @@ int taskset_main(int argc UNUSED_PARAM, char **argv)
                current_new += 8; /* "new" */
        }
 
-       { /* Affinity was specified, translate it into cpu_set_t */
+       /* Affinity was specified, translate it into cpu_set_t */
+       CPU_ZERO(&mask);
+       if (!ENABLE_FEATURE_TASKSET_FANCY) {
                unsigned i;
+               unsigned long long m;
+
                /* Do not allow zero mask: */
-               unsigned long long m = xstrtoull_range(aff, 0, 1, ULLONG_MAX);
-               enum { CNT_BIT = CPU_SETSIZE < sizeof(m)*8 ? CPU_SETSIZE : sizeof(m)*8 };
+               m = xstrtoull_range(aff, 0, 1, ULLONG_MAX);
+               i = 0;
+               do {
+                       if (m & 1)
+                               CPU_SET(i, &mask);
+                       i++;
+                       m >>= 1;
+               } while (m != 0);
+       } else {
+               unsigned i;
+               char *last_byte;
+               char *bin;
+               uint8_t bit_in_byte;
+
+               /* Cheap way to get "long enough" buffer */
+               bin = xstrdup(aff);
+
+               if (aff[0] != '0' && (aff[1]|0x20) != 'x') {
+/* TODO: decimal/octal masks are still limited to 2^64 */
+                       unsigned long long m = xstrtoull_range(aff, 0, 1, ULLONG_MAX);
+                       bin += strlen(bin);
+                       last_byte = bin - 1;
+                       while (m) {
+                               *--bin = m & 0xff;
+                               m >>= 8;
+                       }
+               } else {
+                       /* aff is "0x.....", we accept very long masks in this form */
+                       last_byte = hex2bin(bin, aff + 2, INT_MAX);
+                       if (!last_byte) {
+ bad_aff:
+                               bb_error_msg_and_die("bad affinity '%s'", aff);
+                       }
+                       last_byte--; /* now points to the last byte */
+               }
 
-               CPU_ZERO(&mask);
-               for (i = 0; i < CNT_BIT; i++) {
-                       unsigned long long bit = (1ULL << i);
-                       if (bit & m)
+               i = 0;
+               bit_in_byte = 1;
+               while (last_byte >= bin) {
+                       if (bit_in_byte & *last_byte) {
+                               if (i >= CPU_SETSIZE)
+                                       goto bad_aff;
                                CPU_SET(i, &mask);
+                               //bb_error_msg("bit %d set", i);
+                       }
+                       i++;
+                       /* bit_in_byte is uint8_t! & 0xff is implied */
+                       bit_in_byte = (bit_in_byte << 1);
+                       if (!bit_in_byte) {
+                               bit_in_byte = 1;
+                               last_byte--;
+                       }
                }
        }