Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934472Ab2JXHtJ (ORCPT ); Wed, 24 Oct 2012 03:49:09 -0400 Received: from mga09.intel.com ([134.134.136.24]:25639 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933731Ab2JXHtI (ORCPT ); Wed, 24 Oct 2012 03:49:08 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="4.80,639,1344236400"; d="scan'208";a="209862640" Message-ID: <50879D71.3080108@intel.com> Date: Wed, 24 Oct 2012 15:49:05 +0800 From: "Yan, Zheng" User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:16.0) Gecko/20121016 Thunderbird/16.0.1 MIME-Version: 1.0 To: Stephane Eranian CC: LKML , Peter Zijlstra , "ak@linux.intel.com" Subject: Re: [PATCH V2 1/7] perf, x86: Reduce lbr_sel_map size References: <1351058350-9159-1-git-send-email-zheng.z.yan@intel.com> <1351058350-9159-2-git-send-email-zheng.z.yan@intel.com> In-Reply-To: Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 9278 Lines: 195 On 10/24/2012 03:28 PM, Stephane Eranian wrote: > On Wed, Oct 24, 2012 at 7:59 AM, Yan, Zheng wrote: >> From: "Yan, Zheng" >> >> The index of lbr_sel_map is bit value of perf branch_sample_type. >> By using bit shift as index, we can reduce lbr_sel_map size. >> >> 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 d3b3bb7..ea6749a 100644 >> --- a/arch/x86/kernel/cpu/perf_event.h >> +++ b/arch/x86/kernel/cpu/perf_event.h >> @@ -412,6 +412,10 @@ 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, >> +}; >> + > What's the point on the extraneous definition? because later patches will add map PERF_SAMPLE_BRANCH_CALL_STACK, it will make "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 31fe046..7d9ae5f 100644 >> --- a/arch/x86/kernel/cpu/perf_event_intel_lbr.c >> +++ b/arch/x86/kernel/cpu/perf_event_intel_lbr.c >> @@ -61,10 +61,6 @@ enum { >> #define LBR_FROM_FLAG_INTX (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 >> @@ -378,14 +374,14 @@ 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++) { > > Why not just define for_each_branch_shift()? for_each_branch_sample_type has only one user. I think using for(...) here make code more readable. Regards Yan, Zheng > >> + if (!(br_type & (1U << i))) >> continue; >> >> - v = x86_pmu.lbr_sel_map[m]; >> + v = x86_pmu.lbr_sel_map[i]; >> if (v == LBR_NOT_SUPP) >> return -EOPNOTSUPP; >> >> @@ -631,33 +627,33 @@ 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, >> }; >> >> -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 d1ffdb6..4a735be 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_SHIFT = 7, /* transaction aborts */ >> + PERF_SAMPLE_BRANCH_INTX_SHIFT = 8, /* in transaction */ >> + PERF_SAMPLE_BRANCH_NOTX_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 = 1U << 7, /* transaction aborts */ >> - PERF_SAMPLE_BRANCH_INTX = 1U << 8, /* in transaction (flag) */ >> - PERF_SAMPLE_BRANCH_NOTX = 1U << 9, /* not in transaction (flag) */ >> - >> - 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 = 1U << PERF_SAMPLE_BRANCH_ABORT_SHIFT, >> + PERF_SAMPLE_BRANCH_INTX = 1U << PERF_SAMPLE_BRANCH_INTX_SHIFT, >> + PERF_SAMPLE_BRANCH_NOTX = 1U << PERF_SAMPLE_BRANCH_NOTX_SHIFT, >> + >> + PERF_SAMPLE_BRANCH_MAX = 1U << PERF_SAMPLE_BRANCH_MAX_SHIFT, >> }; >> >> #define PERF_SAMPLE_BRANCH_PLM_ALL \ >> -- >> 1.7.11.7 >> -- 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/