sched: document profile=sleep requiring CONFIG_SCHEDSTATS

profile=sleep only works if CONFIG_SCHEDSTATS is set. This patch notes
the limitation in Documentation/kernel-parameters.txt and prints a
warning at boot-time if profile=sleep is used without CONFIG_SCHEDSTAT.

Signed-off-by: Mel Gorman <mel@csn.ul.ie>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
This commit is contained in:
Mel Gorman 2007-10-24 18:23:50 +02:00 committed by Ingo Molnar
parent 838225b48e
commit b3da2a73ff
2 changed files with 7 additions and 1 deletions

View file

@ -1444,7 +1444,8 @@ and is between 256 and 4096 characters. It is defined in the file
Param: "schedule" - profile schedule points.
Param: <number> - step/bucket size as a power of 2 for
statistical time based profiling.
Param: "sleep" - profile D-state sleeping (millisecs)
Param: "sleep" - profile D-state sleeping (millisecs).
Requires CONFIG_SCHEDSTATS
Param: "kvm" - profile VM exits.
processor.max_cstate= [HW,ACPI]

View file

@ -60,6 +60,7 @@ static int __init profile_setup(char * str)
int par;
if (!strncmp(str, sleepstr, strlen(sleepstr))) {
#ifdef CONFIG_SCHEDSTATS
prof_on = SLEEP_PROFILING;
if (str[strlen(sleepstr)] == ',')
str += strlen(sleepstr) + 1;
@ -68,6 +69,10 @@ static int __init profile_setup(char * str)
printk(KERN_INFO
"kernel sleep profiling enabled (shift: %ld)\n",
prof_shift);
#else
printk(KERN_WARNING
"kernel sleep profiling requires CONFIG_SCHEDSTATS\n");
#endif /* CONFIG_SCHEDSTATS */
} else if (!strncmp(str, schedstr, strlen(schedstr))) {
prof_on = SCHED_PROFILING;
if (str[strlen(schedstr)] == ',')