Allow ranges of CPUs in cpus_allowed option
For a larger number of CPUs, it's a bit of a bother having to set
each one individually. Plus, you typically want to bind to a range of
CPUs, to keep the job core local (or whatever your preference). So extend
cpus_allowed to take ranges of CPU numbers as well. Now you can do:
cpus_allowed=0-7
and have your job confined to CPUs 0 through 7.
Signed-off-by: Jens Axboe <jens.axboe@oracle.com>
diff --git a/HOWTO b/HOWTO
index 5a55c1a..7bd71a9 100644
--- a/HOWTO
+++ b/HOWTO
@@ -590,7 +590,9 @@
cpus_allowed=str Controls the same options as cpumask, but it allows a text
setting of the permitted CPUs instead. So to use CPUs 1 and
- 5, you would specify cpus_allowed=1,5.
+ 5, you would specify cpus_allowed=1,5. This options also
+ allows a range of CPUs. Say you wanted a binding to CPUs
+ 1, 5, and 8-15, you would set cpus_allowed=1,5,8-15.
startdelay=time Start this job the specified number of seconds after fio
has started. Only useful if the job file contains several
diff --git a/options.c b/options.c
index b890420..1953e3d 100644
--- a/options.c
+++ b/options.c
@@ -249,9 +249,12 @@
CPU_ZERO(&td->o.cpumask);
- for (i = 0; i < sizeof(int) * 8; i++)
- if ((1 << i) & *val)
+ for (i = 0; i < sizeof(int) * 8; i++) {
+ if ((1 << i) & *val) {
+ dprint(FD_PARSE, "set cpu allowed %d\n", i);
CPU_SET(*val, &td->o.cpumask);
+ }
+ }
td->o.cpumask_set = 1;
return 0;
@@ -270,9 +273,29 @@
strip_blank_end(str);
while ((cpu = strsep(&str, ",")) != NULL) {
+ char *str2, *cpu2;
+ int icpu, icpu2;
+
if (!strlen(cpu))
break;
- CPU_SET(atoi(cpu), &td->o.cpumask);
+
+ str2 = cpu;
+ icpu2 = -1;
+ while ((cpu2 = strsep(&str2, "-")) != NULL) {
+ if (!strlen(cpu2))
+ break;
+
+ icpu2 = atoi(cpu2);
+ }
+
+ icpu = atoi(cpu);
+ if (icpu2 == -1)
+ icpu2 = icpu;
+ while (icpu <= icpu2) {
+ dprint(FD_PARSE, "set cpu allowed %d\n", icpu);
+ CPU_SET(atoi(cpu), &td->o.cpumask);
+ icpu++;
+ }
}
free(p);