diff options
| author | Thomas Richter <tmricht@linux.ibm.com> | 2021-06-25 15:17:01 +0200 |
|---|---|---|
| committer | Vasily Gorbik <gor@linux.ibm.com> | 2021-07-05 12:44:23 +0200 |
| commit | a029a4eab39e4bf542907a3263773fce3d48c983 (patch) | |
| tree | b8f727b17f20e00e221af9a2096da23108c8ee2b /include | |
| parent | s390/mcck: move register validation to C code (diff) | |
| download | linux-a029a4eab39e4bf542907a3263773fce3d48c983.tar.xz linux-a029a4eab39e4bf542907a3263773fce3d48c983.zip | |
s390/cpumf: Allow concurrent access for CPU Measurement Counter Facility
Commit cf6acb8bdb1d ("s390/cpumf: Add support for complete counter set extraction")
allows access to the CPU Measurement Counter Facility via character
device /dev/hwctr. The access was exclusive via this device or
via perf_event_open() system call. Only one path at a time was
permitted. The CPU Measurement Counter Facility device driver blocked
access to other processes.
This patch removes this restriction and allows concurrent access to
the CPU Measurement Counter Facility from multiple processes at the same
time via perf_event_open() SVC and via /dev/hwctr device. The access
via /dev/hwctr device is still exclusive, only one process is allowed to
access this device.
This patch
- moves the /dev/hwctr device access from file perf_cpum_cf_diag.c.
to file perf_cpum_cf.c.
- use only one trace buffer .../s390dbf/cpum_cf.
- remove cfset_csd structure and includes its members it into the
structure cpu_cf_events. This results in one data structure and
simplifies the access.
- rework function familiy ctr_set_enable, ctr_set_disable, ctr_set_start
and ctr_set_stop which operate on a counter set number.
Now they operate on a counter set bit mask.
- move CF_DIAG event functionality to file perf_cpum_cf.c. It now
contains the complete functionality of the CPU Measurement Counter
Facility:
- Performance measurement support for counters using perf stat.
- Support for complete counter set extraction with device /dev/hwctr.
- Support for counter set extraction event CF_DIAG attached to
samples using perf record.
- removes file perf_cpum_cf_diag.c
Signed-off-by: Thomas Richter <tmricht@linux.ibm.com>
Reviewed-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Signed-off-by: Vasily Gorbik <gor@linux.ibm.com>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/cpuhotplug.h | 1 |
1 files changed, 0 insertions, 1 deletions
diff --git a/include/linux/cpuhotplug.h b/include/linux/cpuhotplug.h index 47e13582d9fc..f39b34b13871 100644 --- a/include/linux/cpuhotplug.h +++ b/include/linux/cpuhotplug.h @@ -171,7 +171,6 @@ enum cpuhp_state { CPUHP_AP_PERF_X86_CSTATE_ONLINE, CPUHP_AP_PERF_X86_IDXD_ONLINE, CPUHP_AP_PERF_S390_CF_ONLINE, - CPUHP_AP_PERF_S390_CFD_ONLINE, CPUHP_AP_PERF_S390_SF_ONLINE, CPUHP_AP_PERF_ARM_CCI_ONLINE, CPUHP_AP_PERF_ARM_CCN_ONLINE, |