Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753031AbaAOR65 (ORCPT ); Wed, 15 Jan 2014 12:58:57 -0500 Received: from smtp.codeaurora.org ([198.145.11.231]:44896 "EHLO smtp.codeaurora.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752650AbaAORzk (ORCPT ); Wed, 15 Jan 2014 12:55:40 -0500 From: Stephen Boyd To: Will Deacon Cc: linux-kernel@vger.kernel.org, linux-arm-msm@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [PATCH v2 4/7] ARM: perf_event: Add hook for event index clearing Date: Wed, 15 Jan 2014 09:55:32 -0800 Message-Id: <1389808535-23852-5-git-send-email-sboyd@codeaurora.org> X-Mailer: git-send-email 1.8.5.2.228.g8f9f19c In-Reply-To: <1389808535-23852-1-git-send-email-sboyd@codeaurora.org> References: <1389808535-23852-1-git-send-email-sboyd@codeaurora.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Krait processors we have a many-to-one relationship between raw CPU events and the event programmed into the PMNx counter. Two raw CPU events could map to the same value programmed in the PMNx counter. To avoid this problem, we check for collisions during the get_event_idx() callback by setting a bit in a bitmap whenever a certain event is used in a PMNx counter (see the next patch). Unfortunately, we don't have a hook to clear this bit in the bitmap when the event is deleted so let's add an optional clear_event_idx() callback for this purpose. Signed-off-by: Stephen Boyd --- arch/arm/include/asm/pmu.h | 1 + arch/arm/kernel/perf_event.c | 2 ++ 2 files changed, 3 insertions(+) diff --git a/arch/arm/include/asm/pmu.h b/arch/arm/include/asm/pmu.h index f24edad26c70..994ac445e792 100644 --- a/arch/arm/include/asm/pmu.h +++ b/arch/arm/include/asm/pmu.h @@ -71,6 +71,7 @@ struct arm_pmu { void (*disable)(struct perf_event *event); int (*get_event_idx)(struct pmu_hw_events *hw_events, struct perf_event *event); + void (*clear_event_idx)(struct perf_event *event); int (*set_event_filter)(struct hw_perf_event *evt, struct perf_event_attr *attr); u32 (*read_counter)(struct perf_event *event); diff --git a/arch/arm/kernel/perf_event.c b/arch/arm/kernel/perf_event.c index e76750980b38..06c6b191c8db 100644 --- a/arch/arm/kernel/perf_event.c +++ b/arch/arm/kernel/perf_event.c @@ -207,6 +207,8 @@ armpmu_del(struct perf_event *event, int flags) armpmu_stop(event, PERF_EF_UPDATE); hw_events->events[idx] = NULL; clear_bit(idx, hw_events->used_mask); + if (armpmu->clear_event_idx) + armpmu->clear_event_idx(event); perf_event_update_userpage(event); } -- The Qualcomm Innovation Center, Inc. is a member of the Code Aurora Forum, hosted by The Linux Foundation -- 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/