Commit 888d5e98 authored by Christian Borntraeger's avatar Christian Borntraeger Committed by Martin Schwidefsky
Browse files

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: default avatarDavid Hildenbrand <dahi@linux.vnet.ibm.com>
Signed-off-by: default avatarChristian Borntraeger <borntraeger@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent d0164ee2

arch/s390/kernel/entry.S

+1 −1
Original line number Diff line number Diff line
@@ -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

arch/s390/kernel/perf_cpum_sf.c

+3 −6
Original line number Diff line number Diff line
@@ -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;

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