From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757440AbcCDNnt (ORCPT ); Fri, 4 Mar 2016 08:43:49 -0500 Received: from mga09.intel.com ([134.134.136.24]:48213 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756468AbcCDNnd (ORCPT ); Fri, 4 Mar 2016 08:43:33 -0500 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.22,535,1449561600"; d="scan'208";a="59824668" From: Alexander Shishkin To: Peter Zijlstra Cc: Ingo Molnar , linux-kernel@vger.kernel.org, vince@deater.net, eranian@google.com, Arnaldo Carvalho de Melo , Alexander Shishkin , Mathieu Poirier Subject: [PATCH v2 4/5] perf/x86/intel/pt: Move transaction start/stop to pmu start/stop callbacks Date: Fri, 4 Mar 2016 15:42:48 +0200 Message-Id: <1457098969-21595-5-git-send-email-alexander.shishkin@linux.intel.com> X-Mailer: git-send-email 2.7.0 In-Reply-To: <1457098969-21595-1-git-send-email-alexander.shishkin@linux.intel.com> References: <1457098969-21595-1-git-send-email-alexander.shishkin@linux.intel.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org As per AUX buffer management requirement, AUX output has to happen between pmu::start and pmu::stop calls so that perf_event_stop() actually stops it and therefore perf can free the aux data after it has called pmu::stop. This patch moves perf_aux_output_{begin,end} from pt_event_{add,del} to pt_event_{start,stop}. As a bonus, we get rid of pt_buffer_is_full(), which is already taken care of by perf_aux_output_begin() anyway. Signed-off-by: Alexander Shishkin Cc: Mathieu Poirier --- arch/x86/events/intel/pt.c | 85 +++++++++++++++------------------------------- 1 file changed, 27 insertions(+), 58 deletions(-) diff --git a/arch/x86/events/intel/pt.c b/arch/x86/events/intel/pt.c index 6af7cf71d6..127f58c179 100644 --- a/arch/x86/events/intel/pt.c +++ b/arch/x86/events/intel/pt.c @@ -906,26 +906,6 @@ static void pt_buffer_free_aux(void *data) } /** - * pt_buffer_is_full() - check if the buffer is full - * @buf: PT buffer. - * @pt: Per-cpu pt handle. - * - * If the user hasn't read data from the output region that aux_head - * points to, the buffer is considered full: the user needs to read at - * least this region and update aux_tail to point past it. - */ -static bool pt_buffer_is_full(struct pt_buffer *buf, struct pt *pt) -{ - if (buf->snapshot) - return false; - - if (local_read(&buf->data_size) >= pt->handle.size) - return true; - - return false; -} - -/** * intel_pt_interrupt() - PT PMI handler */ void intel_pt_interrupt(void) @@ -989,20 +969,33 @@ void intel_pt_interrupt(void) static void pt_event_start(struct perf_event *event, int mode) { + struct hw_perf_event *hwc = &event->hw; struct pt *pt = this_cpu_ptr(&pt_ctx); - struct pt_buffer *buf = perf_get_aux(&pt->handle); + struct pt_buffer *buf; - if (!buf || pt_buffer_is_full(buf, pt)) { - event->hw.state = PERF_HES_STOPPED; - return; + buf = perf_aux_output_begin(&pt->handle, event); + if (!buf) + goto fail_stop; + + pt_buffer_reset_offsets(buf, pt->handle.head); + if (!buf->snapshot) { + if (pt_buffer_reset_markers(buf, &pt->handle)) + goto fail_end_stop; } ACCESS_ONCE(pt->handle_nmi) = 1; - event->hw.state = 0; + hwc->state = 0; pt_config_buffer(buf->cur->table, buf->cur_idx, buf->output_off); pt_config(event); + + return; + +fail_end_stop: + perf_aux_output_end(&pt->handle, 0, true); +fail_stop: + hwc->state = PERF_HES_STOPPED; } static void pt_event_stop(struct perf_event *event, int mode) @@ -1035,19 +1028,7 @@ static void pt_event_stop(struct perf_event *event, int mode) pt_handle_status(pt); pt_update_head(pt); - } -} -static void pt_event_del(struct perf_event *event, int mode) -{ - struct pt *pt = this_cpu_ptr(&pt_ctx); - struct pt_buffer *buf; - - pt_event_stop(event, PERF_EF_UPDATE); - - buf = perf_get_aux(&pt->handle); - - if (buf) { if (buf->snapshot) pt->handle.head = local_xchg(&buf->data_size, @@ -1057,9 +1038,13 @@ static void pt_event_del(struct perf_event *event, int mode) } } +static void pt_event_del(struct perf_event *event, int mode) +{ + pt_event_stop(event, PERF_EF_UPDATE); +} + static int pt_event_add(struct perf_event *event, int mode) { - struct pt_buffer *buf; struct pt *pt = this_cpu_ptr(&pt_ctx); struct hw_perf_event *hwc = &event->hw; int ret = -EBUSY; @@ -1067,34 +1052,18 @@ static int pt_event_add(struct perf_event *event, int mode) if (pt->handle.event) goto fail; - buf = perf_aux_output_begin(&pt->handle, event); - ret = -EINVAL; - if (!buf) - goto fail_stop; - - pt_buffer_reset_offsets(buf, pt->handle.head); - if (!buf->snapshot) { - ret = pt_buffer_reset_markers(buf, &pt->handle); - if (ret) - goto fail_end_stop; - } - if (mode & PERF_EF_START) { pt_event_start(event, 0); - ret = -EBUSY; + ret = -EINVAL; if (hwc->state == PERF_HES_STOPPED) - goto fail_end_stop; + goto fail; } else { hwc->state = PERF_HES_STOPPED; } - return 0; - -fail_end_stop: - perf_aux_output_end(&pt->handle, 0, true); -fail_stop: - hwc->state = PERF_HES_STOPPED; + ret = 0; fail: + return ret; } -- 2.7.0