[PATCH 2/4] powerpc/pseries: Add wait interval counters to VPA

Nicholas Piggin npiggin at gmail.com
Wed May 18 23:39:32 AEST 2022


The hypervisor exposes accumulated partition scheduling interval times
in the VPA (lppaca). These can be used to implement a simple stolen time
in the guest without complex and costly dtl scanning.

Signed-off-by: Nicholas Piggin <npiggin at gmail.com>
---
 arch/powerpc/include/asm/lppaca.h | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/arch/powerpc/include/asm/lppaca.h b/arch/powerpc/include/asm/lppaca.h
index c390ec377bae..34d44cb17c87 100644
--- a/arch/powerpc/include/asm/lppaca.h
+++ b/arch/powerpc/include/asm/lppaca.h
@@ -104,14 +104,18 @@ struct lppaca {
 	volatile __be32 dispersion_count; /* dispatch changed physical cpu */
 	volatile __be64 cmo_faults;	/* CMO page fault count */
 	volatile __be64 cmo_fault_time;	/* CMO page fault time */
-	u8	reserved10[104];
+	u8	reserved10[64];		/* [S]PURR expropriated/donated */
+	volatile __be64 enqueue_dispatch_tb; /* Total TB enqueue->dispatch */
+	volatile __be64 ready_enqueue_tb; /* Total TB ready->enqueue */
+	volatile __be64 wait_ready_tb;	/* Total TB wait->ready */
+	u8	reserved11[16];
 
 	/* cacheline 4-5 */
 
 	__be32	page_ins;		/* CMO Hint - # page ins by OS */
-	u8	reserved11[148];
+	u8	reserved12[148];
 	volatile __be64 dtl_idx;	/* Dispatch Trace Log head index */
-	u8	reserved12[96];
+	u8	reserved13[96];
 } ____cacheline_aligned;
 
 #define lppaca_of(cpu)	(*paca_ptrs[cpu]->lppaca_ptr)
-- 
2.35.1



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