[tip: perf/urgent] perf/x86/rapl: Use standard Energy Unit for SPR Dram RAPL domain

[tip-bot2 for Zhang Rui]

The following commit has been merged into the perf/urgent branch of tip:

Commit-ID:     80275ca9e525c198c7efe045c4a6cdb68a2ea763
Gitweb:        https://git.kernel.org/tip/80275ca9e525c198c7efe045c4a6cdb68a2ea763
Author:        Zhang Rui <rui.zhang@xxxxxxxxx>
AuthorDate:    Sat, 24 Sep 2022 13:47:37 +08:00
Committer:     Peter Zijlstra <peterz@xxxxxxxxxxxxx>
CommitterDate: Wed, 02 Nov 2022 12:22:05 +01:00

perf/x86/rapl: Use standard Energy Unit for SPR Dram RAPL domain

Intel Xeon servers used to use a fixed energy resolution (15.3uj) for
Dram RAPL domain. But on SPR, Dram RAPL domain follows the standard
energy resolution as described in MSR_RAPL_POWER_UNIT.

Remove the SPR Dram energy unit quirk.

Fixes: bcfd218b6679 ("perf/x86/rapl: Add support for Intel SPR platform")
Signed-off-by: Zhang Rui <rui.zhang@xxxxxxxxx>
Signed-off-by: Peter Zijlstra (Intel) <peterz@xxxxxxxxxxxxx>
Reviewed-by: Kan Liang <kan.liang@xxxxxxxxxxxxxxx>
Tested-by: Wang Wendy <wendy.wang@xxxxxxxxx>
Link: https://lkml.kernel.org/r/20220924054738.12076-3-rui.zhang@xxxxxxxxx
---
 arch/x86/events/rapl.c | 6 +-----
 1 file changed, 1 insertion(+), 5 deletions(-)

diff --git a/arch/x86/events/rapl.c b/arch/x86/events/rapl.c
index fea544e..a829492 100644
--- a/arch/x86/events/rapl.c
+++ b/arch/x86/events/rapl.c
@@ -619,12 +619,8 @@ static int rapl_check_hw_unit(struct rapl_model *rm)
 	case RAPL_UNIT_QUIRK_INTEL_HSW:
 		rapl_hw_unit[PERF_RAPL_RAM] = 16;
 		break;
-	/*
-	 * SPR shares the same DRAM domain energy unit as HSW, plus it
-	 * also has a fixed energy unit for Psys domain.
-	 */
+	/* SPR uses a fixed energy unit for Psys domain. */
 	case RAPL_UNIT_QUIRK_INTEL_SPR:
-		rapl_hw_unit[PERF_RAPL_RAM] = 16;
 		rapl_hw_unit[PERF_RAPL_PSYS] = 0;
 		break;
 	default: