From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-9.8 required=3.0 tests=DKIM_SIGNED,DKIM_VALID, DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SIGNED_OFF_BY, SPF_HELO_NONE,SPF_PASS,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1174AC433EF for ; Sun, 8 Sep 2019 12:05:58 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id D97F5218AC for ; Sun, 8 Sep 2019 12:05:57 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="S+7OJ9UU" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1728955AbfIHMF5 (ORCPT ); Sun, 8 Sep 2019 08:05:57 -0400 Received: from mail-pl1-f196.google.com ([209.85.214.196]:39685 "EHLO mail-pl1-f196.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1728935AbfIHMF4 (ORCPT ); Sun, 8 Sep 2019 08:05:56 -0400 Received: by mail-pl1-f196.google.com with SMTP id bd8so5282364plb.6 for ; Sun, 08 Sep 2019 05:05:56 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pocKy7bl+9/9OQKHIyv1k4AbSxuOk9ge9kKmyhR5kl0=; b=S+7OJ9UU0EX1d47DhqK4fa1fzUmL9aIhmNjnArnbNCikxuPW07LemUdK6WLNQ+RkPM QSR1tr+fOOqLWmKP58c7yyBTFrT5WCB5Nh3Hmc3/8GeDRV2rSE5FBJfMZrecvr63oKr1 GU6X++U46LiOtZvICPkJ87VfC2nMV8XRiKeyGpZk5AMPNntUgu2llIz0W5/rzblE3mQJ ruOnuLSkdGeZVbHuiX6W99BEW1ksVVqXrTUO05jqM0qfTieNJu/M95nzJCSZKu4VkcUZ 6gPtGFSejr+3CYtt1pwoCqofstto0aT50+g+n2Ai6I+qsnjP9WNsJQ3fI2fVykbHAlxB w/PA== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:mime-version :content-transfer-encoding; bh=pocKy7bl+9/9OQKHIyv1k4AbSxuOk9ge9kKmyhR5kl0=; b=heMBwAzgwn8XdVhaCbD1Ng4Uhm24fu3PD0f++rp0QCS4ocmUB7CCQ3ls9B7sQgLWFd Mqu3fNqYl+iVSDsFHXYSjwQGnyET7Qn9f5PCriK2UI4cnMp3Ervb2CNWUnwD5VsabPB2 XZ1sP5dNqANc1hFKsGoCWvnInqjTw7OtzCBQKun+TdKTWvF1ivTN6l6JDGl3Udn+5pmm p7DmhzZ04JeIGjIhNACTQxtRtNYllSVYHu7wg/CpqwxrAoNYWDDiopHAwpBYSKAt08uh z+2r2xdYGFp71rvZlAp8VvziQY63CPBrm58EPg0d9acyA1fYPNVN9FM7144sY/0NVgCC l/Tw== X-Gm-Message-State: APjAAAVkJPprSQA/BLpTz31bqHNKJE/D32s8upd55bg7jif7m2wLYoJb YdQ9c103P7rmt8Bu7qfT0WU= X-Google-Smtp-Source: APXvYqxLIyU2FkUeL9Wj0l/iDK5k40wl6THEYMKwThp3gzWLaoWZITTgsFoF6CkwDk0sTt4fWSHkKQ== X-Received: by 2002:a17:902:b40c:: with SMTP id x12mr19300553plr.236.1567944356110; Sun, 08 Sep 2019 05:05:56 -0700 (PDT) Received: from localhost.localdomain ([149.28.153.17]) by smtp.gmail.com with ESMTPSA id v22sm9327843pgk.69.2019.09.08.05.05.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 08 Sep 2019 05:05:55 -0700 (PDT) From: Changbin Du To: Steven Rostedt Cc: Ingo Molnar , linux-kernel@vger.kernel.org, Changbin Du Subject: [PATCH] ftrace: simplify ftrace hash lookup code Date: Sun, 8 Sep 2019 20:05:45 +0800 Message-Id: <20190908120545.11614-1-changbin.du@gmail.com> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-kernel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Function ftrace_lookup_ip() will check empty hash table. So we don't need extra check outside. Signed-off-by: Changbin Du --- kernel/trace/ftrace.c | 15 ++++----------- kernel/trace/trace.h | 6 ------ 2 files changed, 4 insertions(+), 17 deletions(-) diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c index f9821a3374e9..85115deca667 100644 --- a/kernel/trace/ftrace.c +++ b/kernel/trace/ftrace.c @@ -1461,10 +1461,8 @@ static bool hash_contains_ip(unsigned long ip, * considered a match for the filter hash, but an empty * notrace hash is considered not in the notrace hash. */ - return (ftrace_hash_empty(hash->filter_hash) || - __ftrace_lookup_ip(hash->filter_hash, ip)) && - (ftrace_hash_empty(hash->notrace_hash) || - !__ftrace_lookup_ip(hash->notrace_hash, ip)); + return ftrace_lookup_ip(hash->filter_hash, ip) && + !ftrace_lookup_ip(hash->notrace_hash, ip); } /* @@ -2890,8 +2888,7 @@ ops_references_rec(struct ftrace_ops *ops, struct dyn_ftrace *rec) return true; /* The function must be in the filter */ - if (!ftrace_hash_empty(ops->func_hash->filter_hash) && - !__ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) + if (!ftrace_lookup_ip(ops->func_hash->filter_hash, rec->ip)) return false; /* If in notrace hash, we ignore it too */ @@ -6036,11 +6033,7 @@ clear_func_from_hash(struct ftrace_init_func *func, struct ftrace_hash *hash) { struct ftrace_func_entry *entry; - if (ftrace_hash_empty(hash)) - return; - - entry = __ftrace_lookup_ip(hash, func->ip); - + entry = ftrace_lookup_ip(hash, func->ip); /* * Do not allow this rec to match again. * Yeah, it may waste some memory, but will be removed diff --git a/kernel/trace/trace.h b/kernel/trace/trace.h index 005f08629b8b..74162bc4024d 100644 --- a/kernel/trace/trace.h +++ b/kernel/trace/trace.h @@ -941,11 +941,6 @@ static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace) preempt_disable_notrace(); - if (ftrace_hash_empty(ftrace_graph_hash)) { - ret = 1; - goto out; - } - if (ftrace_lookup_ip(ftrace_graph_hash, addr)) { /* @@ -967,7 +962,6 @@ static inline int ftrace_graph_addr(struct ftrace_graph_ent *trace) ret = 1; } -out: preempt_enable_notrace(); return ret; } -- 2.20.1