Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751989AbdFHIPj (ORCPT ); Thu, 8 Jun 2017 04:15:39 -0400 Received: from bombadil.infradead.org ([65.50.211.133]:36150 "EHLO bombadil.infradead.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751880AbdFHIPg (ORCPT ); Thu, 8 Jun 2017 04:15:36 -0400 Date: Thu, 8 Jun 2017 10:15:31 +0200 From: Peter Zijlstra To: Andi Kleen Cc: acme@kernel.org, linux-kernel@vger.kernel.org, jolsa@kernel.org, eranian@google.com, Andi Kleen , sukadev@linux.vnet.ibm.com, maddy@linux.vnet.ibm.com Subject: Re: [PATCH v2 2/4] perf/x86: Fix data source decoding for Skylake Message-ID: <20170608081531.iv27xaghntniwmm6@hirez.programming.kicks-ass.net> References: <20170607232226.26365-1-andi@firstfloor.org> <20170607232226.26365-3-andi@firstfloor.org> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20170607232226.26365-3-andi@firstfloor.org> User-Agent: NeoMutt/20170113 (1.7.2) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2373 Lines: 69 On Wed, Jun 07, 2017 at 04:22:24PM -0700, Andi Kleen wrote: > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h > index b1c0b187acfe..95daade294d7 100644 > --- a/include/uapi/linux/perf_event.h > +++ b/include/uapi/linux/perf_event.h > @@ -931,14 +931,18 @@ union perf_mem_data_src { > mem_snoop:5, /* snoop mode */ > mem_lock:2, /* lock instr */ > mem_dtlb:7, /* tlb access */ > - mem_rsvd:31; > + mem_lvlx:8, /* memory hierarchy level, ext */ > + mem_snoopx:2, /* snoop mode, ext */ > + mem_rsvd:21; > }; > }; > #elif defined(__BIG_ENDIAN_BITFIELD) > union perf_mem_data_src { > __u64 val; > struct { > - __u64 mem_rsvd:31, > + __u64 mem_rsvd:21, > + mem_snoopx:2, /* snoop mode, ext */ > + mem_lvlx:8, /* memory hierarchy level, ext */ > mem_dtlb:7, /* tlb access */ > mem_lock:2, /* lock instr */ > mem_snoop:5, /* snoop mode */ So one thing we could do is add a mem_hops field and always set that, even for the old stuff. The old stuff will not know about that field and ignore the bits, but new stuff will then not need as many LVL bits. Of course, we then get into the problem of how many bits of hops we need.. Power guys ? > @@ -975,6 +979,16 @@ union perf_mem_data_src { > #define PERF_MEM_LVL_UNC 0x2000 /* Uncached memory */ > #define PERF_MEM_LVL_SHIFT 5 > > +#define PERF_MEM_LVLX_L4 0x01 /* L4 */ > +#define PERF_MEM_LVLX_REM_L4 0x02 /* Remote L4 */ > +#define PERF_MEM_LVLX_REM_RAM 0x04 /* Remote Ram, unknown hops */ > +#define PERF_MEM_LVLX_PMEM 0x08 /* Persistent Memory */ > +#define PERF_MEM_LVLX_REM_PMEM 0x10 /* Remote Persistent Memory */ > +#define PERF_MEM_LVLX_REM_NA 0x20 /* Remote N/A level */ Still wondering what the point of REM_NA is.. can you explain? > +/* 2 free */ > + > +#define PERF_MEM_LVLX_SHIFT 33 > + > /* snoop mode */ > #define PERF_MEM_SNOOP_NA 0x01 /* not available */ > #define PERF_MEM_SNOOP_NONE 0x02 /* no snoop */ > @@ -983,6 +997,10 @@ union perf_mem_data_src { > #define PERF_MEM_SNOOP_HITM 0x10 /* snoop hit modified */ > #define PERF_MEM_SNOOP_SHIFT 19 > > +#define PERF_MEM_SNOOPX_FWD 0x01 /* forward */ > +/* 1 free */ > +#define PERF_MEM_SNOOPX_SHIFT 41 > + > /* locked instruction */ > #define PERF_MEM_LOCK_NA 0x01 /* not available */ > #define PERF_MEM_LOCK_LOCKED 0x02 /* locked transaction */ > -- > 2.9.4 >