Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752559AbdIVUAv (ORCPT ); Fri, 22 Sep 2017 16:00:51 -0400 Received: from mga02.intel.com ([134.134.136.20]:33935 "EHLO mga02.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751915AbdIVUAs (ORCPT ); Fri, 22 Sep 2017 16:00:48 -0400 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.42,427,1500966000"; d="scan'208";a="152351846" From: Tom Zanussi To: rostedt@goodmis.org Cc: tglx@linutronix.de, mhiramat@kernel.org, namhyung@kernel.org, vedang.patel@intel.com, bigeasy@linutronix.de, joel.opensrc@gmail.com, joelaf@google.com, mathieu.desnoyers@efficios.com, baohong.liu@intel.com, rajvi.jingar@intel.com, linux-kernel@vger.kernel.org, linux-rt-users@vger.kernel.org Subject: [PATCH v3 02/33] tracing: Remove code which merges duplicates Date: Fri, 22 Sep 2017 14:59:42 -0500 Message-Id: <2f7cdb5a34f63ad5a83be70f42f674002a3eb421.1506105131.git.tom.zanussi@linux.intel.com> X-Mailer: git-send-email 1.9.3 In-Reply-To: References: In-Reply-To: References: Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 5967 Lines: 192 From: Vedang Patel We now have the logic to detect and remove duplicates in the tracing_map hash table. The code which merges duplicates in the histogram is redundant now. So, modify this code just to detect duplicates. The duplication detection code is still kept to ensure that any rare race condition which might cause duplicates does not go unnoticed. Signed-off-by: Vedang Patel --- kernel/trace/trace_events_hist.c | 11 ------ kernel/trace/tracing_map.c | 83 +++------------------------------------- kernel/trace/tracing_map.h | 7 ---- 3 files changed, 6 insertions(+), 95 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 4eddc19..c57e536 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -340,16 +340,6 @@ static int hist_trigger_elt_comm_alloc(struct tracing_map_elt *elt) return 0; } -static void hist_trigger_elt_comm_copy(struct tracing_map_elt *to, - struct tracing_map_elt *from) -{ - char *comm_from = from->private_data; - char *comm_to = to->private_data; - - if (comm_from) - memcpy(comm_to, comm_from, TASK_COMM_LEN + 1); -} - static void hist_trigger_elt_comm_init(struct tracing_map_elt *elt) { char *comm = elt->private_data; @@ -360,7 +350,6 @@ static void hist_trigger_elt_comm_init(struct tracing_map_elt *elt) static const struct tracing_map_ops hist_trigger_elt_comm_ops = { .elt_alloc = hist_trigger_elt_comm_alloc, - .elt_copy = hist_trigger_elt_comm_copy, .elt_free = hist_trigger_elt_comm_free, .elt_init = hist_trigger_elt_comm_init, }; diff --git a/kernel/trace/tracing_map.c b/kernel/trace/tracing_map.c index b30f343..f47a4d5 100644 --- a/kernel/trace/tracing_map.c +++ b/kernel/trace/tracing_map.c @@ -847,67 +847,15 @@ void tracing_map_destroy_sort_entries(struct tracing_map_sort_entry **entries, return sort_entry; } -static struct tracing_map_elt *copy_elt(struct tracing_map_elt *elt) -{ - struct tracing_map_elt *dup_elt; - unsigned int i; - - dup_elt = tracing_map_elt_alloc(elt->map); - if (IS_ERR(dup_elt)) - return NULL; - - if (elt->map->ops && elt->map->ops->elt_copy) - elt->map->ops->elt_copy(dup_elt, elt); - - dup_elt->private_data = elt->private_data; - memcpy(dup_elt->key, elt->key, elt->map->key_size); - - for (i = 0; i < elt->map->n_fields; i++) { - atomic64_set(&dup_elt->fields[i].sum, - atomic64_read(&elt->fields[i].sum)); - dup_elt->fields[i].cmp_fn = elt->fields[i].cmp_fn; - } - - return dup_elt; -} - -static int merge_dup(struct tracing_map_sort_entry **sort_entries, - unsigned int target, unsigned int dup) -{ - struct tracing_map_elt *target_elt, *elt; - bool first_dup = (target - dup) == 1; - int i; - - if (first_dup) { - elt = sort_entries[target]->elt; - target_elt = copy_elt(elt); - if (!target_elt) - return -ENOMEM; - sort_entries[target]->elt = target_elt; - sort_entries[target]->elt_copied = true; - } else - target_elt = sort_entries[target]->elt; - - elt = sort_entries[dup]->elt; - - for (i = 0; i < elt->map->n_fields; i++) - atomic64_add(atomic64_read(&elt->fields[i].sum), - &target_elt->fields[i].sum); - - sort_entries[dup]->dup = true; - - return 0; -} - -static int merge_dups(struct tracing_map_sort_entry **sort_entries, +static void detect_dups(struct tracing_map_sort_entry **sort_entries, int n_entries, unsigned int key_size) { unsigned int dups = 0, total_dups = 0; - int err, i, j; + int i; void *key; if (n_entries < 2) - return total_dups; + return; sort(sort_entries, n_entries, sizeof(struct tracing_map_sort_entry *), (int (*)(const void *, const void *))cmp_entries_dup, NULL); @@ -916,30 +864,14 @@ static int merge_dups(struct tracing_map_sort_entry **sort_entries, for (i = 1; i < n_entries; i++) { if (!memcmp(sort_entries[i]->key, key, key_size)) { dups++; total_dups++; - err = merge_dup(sort_entries, i - dups, i); - if (err) - return err; continue; } key = sort_entries[i]->key; dups = 0; } - if (!total_dups) - return total_dups; - - for (i = 0, j = 0; i < n_entries; i++) { - if (!sort_entries[i]->dup) { - sort_entries[j] = sort_entries[i]; - if (j++ != i) - sort_entries[i] = NULL; - } else { - destroy_sort_entry(sort_entries[i]); - sort_entries[i] = NULL; - } - } - - return total_dups; + WARN_ONCE(total_dups > 0, + "Duplicates detected: %d\n", total_dups); } static bool is_key(struct tracing_map *map, unsigned int field_idx) @@ -1065,10 +997,7 @@ int tracing_map_sort_entries(struct tracing_map *map, return 1; } - ret = merge_dups(entries, n_entries, map->key_size); - if (ret < 0) - goto free; - n_entries -= ret; + detect_dups(entries, n_entries, map->key_size); if (is_key(map, sort_keys[0].field_idx)) cmp_entries_fn = cmp_entries_key; diff --git a/kernel/trace/tracing_map.h b/kernel/trace/tracing_map.h index f097511..98ef6d6 100644 --- a/kernel/trace/tracing_map.h +++ b/kernel/trace/tracing_map.h @@ -214,11 +214,6 @@ struct tracing_map { * Element allocation occurs before tracing begins, when the * tracing_map_init() call is made by client code. * - * @elt_copy: At certain points in the lifetime of an element, it may - * need to be copied. The copy should include a copy of the - * client-allocated data, which can be copied into the 'to' - * element from the 'from' element. - * * @elt_free: When a tracing_map_elt is freed, this function is called * and allows client-allocated per-element data to be freed. * @@ -232,8 +227,6 @@ struct tracing_map { */ struct tracing_map_ops { int (*elt_alloc)(struct tracing_map_elt *elt); - void (*elt_copy)(struct tracing_map_elt *to, - struct tracing_map_elt *from); void (*elt_free)(struct tracing_map_elt *elt); void (*elt_clear)(struct tracing_map_elt *elt); void (*elt_init)(struct tracing_map_elt *elt); -- 1.9.3