KVM: s390: use pid of cpu thread for sampling tagging

Right now we use the address of the sie control block as tag for
the sampling data. This is hard to get for users. Let's just use
the PID of the cpu thread to mark the hardware samples.

Reviewed-by: David Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: Christian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Christian Borntraeger 2015-07-09 17:56:13 +02:00 committed by Martin Schwidefsky
parent d0164ee20d
commit 888d5e9804
2 changed files with 4 additions and 7 deletions

View file

@ -199,7 +199,7 @@ ENTRY(sie64a)
jo .Lsie_skip # exit if fp/vx regs changed
tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_LPP
jz .Lsie_enter
.insn s,0xb2800000,__SF_EMPTY(%r15) # set guest id
.insn s,0xb2800000,__LC_CURRENT_PID # set guest id to pid
.Lsie_enter:
sie 0(%r14)
tm __LC_MACHINE_FLAGS+6,0x20 # MACHINE_FLAG_LPP

View file

@ -1019,12 +1019,9 @@ static int perf_push_sample(struct perf_event *event, struct sf_raw_sample *sfr)
break;
}
/* The host-program-parameter (hpp) contains the sie control
* block that is set by sie64a() in entry64.S. Check if hpp
* refers to a valid control block and set sde_regs flags
* accordingly. This would allow to use hpp values for other
* purposes too.
* For now, simply use a non-zero value as guest indicator.
/* The host-program-parameter (hpp) contains the pid of
* the CPU thread as set by sie64a() in entry.S.
* If non-zero assume a guest sample.
*/
if (sfr->basic.hpp)
sde_regs->in_guest = 1;