Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751367Ab3FYMdF (ORCPT ); Tue, 25 Jun 2013 08:33:05 -0400 Received: from mail-oa0-f44.google.com ([209.85.219.44]:58114 "EHLO mail-oa0-f44.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1750784Ab3FYMdC (ORCPT ); Tue, 25 Jun 2013 08:33:02 -0400 MIME-Version: 1.0 In-Reply-To: <1372150039-15151-2-git-send-email-zheng.z.yan@intel.com> References: <1372150039-15151-1-git-send-email-zheng.z.yan@intel.com> <1372150039-15151-2-git-send-email-zheng.z.yan@intel.com> Date: Tue, 25 Jun 2013 14:33:01 +0200 Message-ID: Subject: Re: [PATCH 1/7] perf, x86: Reduce lbr_sel_map size From: Stephane Eranian To: "Yan, Zheng" Cc: LKML , Ingo Molnar , Peter Zijlstra , Andi Kleen Content-Type: text/plain; charset=UTF-8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8924 Lines: 188 On Tue, Jun 25, 2013 at 10:47 AM, Yan, Zheng wrote: > From: "Yan, Zheng" > > The index of lbr_sel_map is bit value of perf branch_sample_type. > We can reduce lbr_sel_map size by using bit shift as index. > > Signed-off-by: Yan, Zheng > --- > arch/x86/kernel/cpu/perf_event.h | 4 +++ > arch/x86/kernel/cpu/perf_event_intel_lbr.c | 50 ++++++++++++++---------------- > include/uapi/linux/perf_event.h | 42 +++++++++++++++++-------- > 3 files changed, 56 insertions(+), 40 deletions(-) > > diff --git a/arch/x86/kernel/cpu/perf_event.h b/arch/x86/kernel/cpu/perf_event.h > index 108dc75..a74d554 100644 > --- a/arch/x86/kernel/cpu/perf_event.h > +++ b/arch/x86/kernel/cpu/perf_event.h > @@ -447,6 +447,10 @@ struct x86_pmu { > struct perf_guest_switch_msr *(*guest_get_msrs)(int *nr); > }; > > +enum { > + PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE = PERF_SAMPLE_BRANCH_MAX_SHIFT, > +}; > + > #define x86_add_quirk(func_) \ > do { \ > static struct x86_pmu_quirk __quirk __initdata = { \ > diff --git a/arch/x86/kernel/cpu/perf_event_intel_lbr.c b/arch/x86/kernel/cpu/perf_event_intel_lbr.c > index d5be06a..a72e9e9 100644 > --- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c > +++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c > @@ -69,10 +69,6 @@ static enum { > #define LBR_FROM_FLAG_IN_TX (1ULL << 62) > #define LBR_FROM_FLAG_ABORT (1ULL << 61) > > -#define for_each_branch_sample_type(x) \ > - for ((x) = PERF_SAMPLE_BRANCH_USER; \ > - (x) < PERF_SAMPLE_BRANCH_MAX; (x) <<= 1) > - > /* > * x86control flow change classification > * x86control flow changes include branches, interrupts, traps, faults > @@ -387,14 +383,14 @@ static int intel_pmu_setup_hw_lbr_filter(struct perf_event *event) > { > struct hw_perf_event_extra *reg; > u64 br_type = event->attr.branch_sample_type; > - u64 mask = 0, m; > - u64 v; > + u64 mask = 0, v; > + int i; > > - for_each_branch_sample_type(m) { > - if (!(br_type & m)) > + for (i = 0; i < PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE; i++) { > + if (!(br_type & (1U << i))) Needs to be 1ULL to avoid bug later on. br_type is u64. > continue; > > - v = x86_pmu.lbr_sel_map[m]; > + v = x86_pmu.lbr_sel_map[i]; > if (v == LBR_NOT_SUPP) > return -EOPNOTSUPP; > > @@ -649,33 +645,33 @@ intel_pmu_lbr_filter(struct cpu_hw_events *cpuc) > /* > * Map interface branch filters onto LBR filters > */ > -static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX] = { > - [PERF_SAMPLE_BRANCH_ANY] = LBR_ANY, > - [PERF_SAMPLE_BRANCH_USER] = LBR_USER, > - [PERF_SAMPLE_BRANCH_KERNEL] = LBR_KERNEL, > - [PERF_SAMPLE_BRANCH_HV] = LBR_IGN, > - [PERF_SAMPLE_BRANCH_ANY_RETURN] = LBR_RETURN | LBR_REL_JMP > - | LBR_IND_JMP | LBR_FAR, > +static const int nhm_lbr_sel_map[PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE] = { > + [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, > + [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, > + [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, > + [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, > + [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_REL_JMP > + | LBR_IND_JMP | LBR_FAR, > /* > * NHM/WSM erratum: must include REL_JMP+IND_JMP to get CALL branches > */ > - [PERF_SAMPLE_BRANCH_ANY_CALL] = > + [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = > LBR_REL_CALL | LBR_IND_CALL | LBR_REL_JMP | LBR_IND_JMP | LBR_FAR, > /* > * NHM/WSM erratum: must include IND_JMP to capture IND_CALL > */ > - [PERF_SAMPLE_BRANCH_IND_CALL] = LBR_IND_CALL | LBR_IND_JMP, > + [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL | LBR_IND_JMP, > }; > I think it would ease formatting readability if the indexes could be constructed from a simple macro: #define BR_SHIFT(a) \ PERF_SAMPLE_##a##_SHIFT #define BR_SMPL(a) \ PERF_SAMPLE_##a > -static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_MAX] = { > - [PERF_SAMPLE_BRANCH_ANY] = LBR_ANY, > - [PERF_SAMPLE_BRANCH_USER] = LBR_USER, > - [PERF_SAMPLE_BRANCH_KERNEL] = LBR_KERNEL, > - [PERF_SAMPLE_BRANCH_HV] = LBR_IGN, > - [PERF_SAMPLE_BRANCH_ANY_RETURN] = LBR_RETURN | LBR_FAR, > - [PERF_SAMPLE_BRANCH_ANY_CALL] = LBR_REL_CALL | LBR_IND_CALL > - | LBR_FAR, > - [PERF_SAMPLE_BRANCH_IND_CALL] = LBR_IND_CALL, > +static const int snb_lbr_sel_map[PERF_SAMPLE_BRANCH_SELECT_MAP_SIZE] = { > + [PERF_SAMPLE_BRANCH_ANY_SHIFT] = LBR_ANY, > + [PERF_SAMPLE_BRANCH_USER_SHIFT] = LBR_USER, > + [PERF_SAMPLE_BRANCH_KERNEL_SHIFT] = LBR_KERNEL, > + [PERF_SAMPLE_BRANCH_HV_SHIFT] = LBR_IGN, > + [PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT] = LBR_RETURN | LBR_FAR, > + [PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT] = LBR_REL_CALL | LBR_IND_CALL > + | LBR_FAR, > + [PERF_SAMPLE_BRANCH_IND_CALL_SHIFT] = LBR_IND_CALL, > }; > > /* core */ > diff --git a/include/uapi/linux/perf_event.h b/include/uapi/linux/perf_event.h > index 0b1df41..2ec219e 100644 > --- a/include/uapi/linux/perf_event.h > +++ b/include/uapi/linux/perf_event.h > @@ -148,20 +148,36 @@ enum perf_event_sample_format { > * The branch types can be combined, however BRANCH_ANY covers all types > * of branches and therefore it supersedes all the other types. > */ > +enum perf_branch_sample_type_shift { > + PERF_SAMPLE_BRANCH_USER_SHIFT = 0, /* user branches */ > + PERF_SAMPLE_BRANCH_KERNEL_SHIFT = 1, /* kernel branches */ > + PERF_SAMPLE_BRANCH_HV_SHIFT = 2, /* hypervisor branches */ > + > + PERF_SAMPLE_BRANCH_ANY_SHIFT = 3, /* any branch types */ > + PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT = 4, /* any call branch */ > + PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT = 5, /* any return branch */ > + PERF_SAMPLE_BRANCH_IND_CALL_SHIFT = 6, /* indirect calls */ > + PERF_SAMPLE_BRANCH_ABORT_TX_SHIFT = 7, /* transaction aborts */ > + PERF_SAMPLE_BRANCH_IN_TX_SHIFT = 8, /* in transaction */ > + PERF_SAMPLE_BRANCH_NO_TX_SHIFT = 9, /* not in transaction */ > + > + PERF_SAMPLE_BRANCH_MAX_SHIFT /* non-ABI */ > +}; > + > enum perf_branch_sample_type { > - PERF_SAMPLE_BRANCH_USER = 1U << 0, /* user branches */ > - PERF_SAMPLE_BRANCH_KERNEL = 1U << 1, /* kernel branches */ > - PERF_SAMPLE_BRANCH_HV = 1U << 2, /* hypervisor branches */ > - > - PERF_SAMPLE_BRANCH_ANY = 1U << 3, /* any branch types */ > - PERF_SAMPLE_BRANCH_ANY_CALL = 1U << 4, /* any call branch */ > - PERF_SAMPLE_BRANCH_ANY_RETURN = 1U << 5, /* any return branch */ > - PERF_SAMPLE_BRANCH_IND_CALL = 1U << 6, /* indirect calls */ > - PERF_SAMPLE_BRANCH_ABORT_TX = 1U << 7, /* transaction aborts */ > - PERF_SAMPLE_BRANCH_IN_TX = 1U << 8, /* in transaction */ > - PERF_SAMPLE_BRANCH_NO_TX = 1U << 9, /* not in transaction */ > - > - PERF_SAMPLE_BRANCH_MAX = 1U << 10, /* non-ABI */ > + PERF_SAMPLE_BRANCH_USER = 1U << PERF_SAMPLE_BRANCH_USER_SHIFT, > + PERF_SAMPLE_BRANCH_KERNEL = 1U << PERF_SAMPLE_BRANCH_KERNEL_SHIFT, > + PERF_SAMPLE_BRANCH_HV = 1U << PERF_SAMPLE_BRANCH_HV_SHIFT, > + > + PERF_SAMPLE_BRANCH_ANY = 1U << PERF_SAMPLE_BRANCH_ANY_SHIFT, > + PERF_SAMPLE_BRANCH_ANY_CALL = 1U << PERF_SAMPLE_BRANCH_ANY_CALL_SHIFT, > + PERF_SAMPLE_BRANCH_ANY_RETURN = 1U << PERF_SAMPLE_BRANCH_ANY_RETURN_SHIFT, > + PERF_SAMPLE_BRANCH_IND_CALL = 1U << PERF_SAMPLE_BRANCH_IND_CALL_SHIFT, > + PERF_SAMPLE_BRANCH_ABORT_TX = 1U << PERF_SAMPLE_BRANCH_ABORT_TX_SHIFT, > + PERF_SAMPLE_BRANCH_IN_TX = 1U << PERF_SAMPLE_BRANCH_IN_TX_SHIFT, > + PERF_SAMPLE_BRANCH_NO_TX = 1U << PERF_SAMPLE_BRANCH_NO_TX_SHIFT, > + > + PERF_SAMPLE_BRANCH_MAX = 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT, > }; > > #define PERF_SAMPLE_BRANCH_PLM_ALL \ > -- > 1.8.1.4 > -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/