diff options
| author | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2015-01-14 17:52:10 +0100 |
|---|---|---|
| committer | Martin Schwidefsky <schwidefsky@de.ibm.com> | 2015-01-22 12:16:01 +0100 |
| commit | 10ad34bc76dfbc49bda327a13012f6754c0c72e0 (patch) | |
| tree | 4d76fb6882da2eb3e77b53c4fe64f6367ffbd79d /arch/s390/include/asm/sigp.h | |
| parent | 1f6b83e5e4d3aed46eac1d219322fba9c7341cd8 (diff) | |
s390: add SMT support
The multi-threading facility is introduced with the z13 processor family.
This patch adds code to detect the multi-threading facility. With the
facility enabled each core will surface multiple hardware threads to the
system. Each hardware threads looks like a normal CPU to the operating
system with all its registers and properties.
The SCLP interface reports the SMT topology indirectly via the maximum
thread id. Each reported CPU in the result of a read-scp-information
is a core representing a number of hardware threads.
To reflect the reduced CPU capacity if two hardware threads run on a
single core the MT utilization counter set is used to normalize the
raw cputime obtained by the CPU timer deltas. This scaled cputime is
reported via the taskstats interface. The normal /proc/stat numbers
are based on the raw cputime and are not affected by the normalization.
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
Diffstat (limited to 'arch/s390/include/asm/sigp.h')
| -rw-r--r-- | arch/s390/include/asm/sigp.h | 1 |
1 files changed, 1 insertions, 0 deletions
diff --git a/arch/s390/include/asm/sigp.h b/arch/s390/include/asm/sigp.h index 49576115dbb7..c49d9c0483a8 100644 --- a/arch/s390/include/asm/sigp.h +++ b/arch/s390/include/asm/sigp.h @@ -15,6 +15,7 @@ #define SIGP_SET_ARCHITECTURE 18 #define SIGP_COND_EMERGENCY_SIGNAL 19 #define SIGP_SENSE_RUNNING 21 +#define SIGP_SET_MULTI_THREADING 22 #define SIGP_STORE_ADDITIONAL_STATUS 23 /* SIGP condition codes */ |