From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from out-185.mta0.migadu.com (out-185.mta0.migadu.com [91.218.175.185]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id D4BFC7FBC1 for ; Thu, 9 May 2024 02:30:24 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=91.218.175.185 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715221826; cv=none; b=aCXnXWSUDESosRKSw+sPhxoXwhaSekrgRWDYxhk5wHur1owuVR9w1sRyEVzxO5gIugZWNB4JTCegq0QYefHE0EZ7DvsdgdyDO8DhBYWeYeL4glKzU4OoKhQ42omWZC3OWzsaLvHgWBL+tU3VmL3dtn/psbDGvHLrZvB7XSNSMIk= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1715221826; c=relaxed/simple; bh=DxL2njOvOlc826jZDyZXagIcQqGRCSurHQ9CsFRdCwQ=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=DjqlPqOxEHflJiWmQD8p5KlwVeuB9tJWFkbgHdkRxskEM4dxWIrS902d7mIrisJWraac+QdsBCdjBw9FqrBWq417fnEmlk5Kn3epbDVPGo72Tja6yfXiPcdDzjpbvmNv3IC8DU3zlLrRGW+DyMqsS7JQjOD0qo9d6CreVLlVQHE= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev; spf=pass smtp.mailfrom=linux.dev; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b=M1WBYTOj; arc=none smtp.client-ip=91.218.175.185 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=linux.dev Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=linux.dev Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linux.dev header.i=@linux.dev header.b="M1WBYTOj" X-Report-Abuse: Please report any abuse attempt to abuse@migadu.com and include these headers. DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux.dev; s=key1; t=1715221823; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=Pqu4RF8vvyMyKw/ZAvbG+SK8gEco48VOR/lnKCC+FPM=; b=M1WBYTOjTupimp+yC4uVX2GEtId2M6frVeoJFYo42fuwnlAIMBFjtOTv+pfYSTjxkqinJj NSEhtkr+7nzJD3bVDzHxK1ZcwHdT+yUiw1MDpovqm5KAC7FhuTPB1Zg7u18sc4U1vNnZmW AZV8oGZE+S7tNQzO9nDacbPw2WCpYDw= From: George Guo To: gregkh@linuxfoundation.org, rostedt@goodmis.org, mhiramat@kernel.org, tom.zanussi@linux.intel.com Cc: stable@vger.kernel.org, Namhyung Kim , George Guo Subject: [PATCH 4.19.y 07/13] tracing: Use str_has_prefix() helper for histogram code Date: Thu, 9 May 2024 10:29:25 +0800 Message-Id: <20240509022931.3513365-8-dongtai.guo@linux.dev> In-Reply-To: <20240509022931.3513365-1-dongtai.guo@linux.dev> References: <20240509022931.3513365-1-dongtai.guo@linux.dev> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Migadu-Flow: FLOW_OUT From: "Steven Rostedt (VMware)" commit 754481e6954cbef53f8bc4412ad48dde611e21d3 upstream. The tracing histogram code contains a lot of instances of the construct: strncmp(str, "const", sizeof("const") - 1) This can be prone to bugs due to typos or bad cut and paste. Use the str_has_prefix() helper macro instead that removes the need for having two copies of the constant string. Cc: Tom Zanussi Acked-by: Namhyung Kim Signed-off-by: Steven Rostedt (VMware) Signed-off-by: George Guo --- kernel/trace/trace_events_hist.c | 32 ++++++++++++++++---------------- 1 file changed, 16 insertions(+), 16 deletions(-) diff --git a/kernel/trace/trace_events_hist.c b/kernel/trace/trace_events_hist.c index 1139075a6395..1441c3934cbf 100644 --- a/kernel/trace/trace_events_hist.c +++ b/kernel/trace/trace_events_hist.c @@ -1878,8 +1878,8 @@ static int parse_action(char *str, struct hist_trigger_attrs *attrs) if (attrs->n_actions >= HIST_ACTIONS_MAX) return ret; - if ((strncmp(str, "onmatch(", strlen("onmatch(")) == 0) || - (strncmp(str, "onmax(", strlen("onmax(")) == 0)) { + if ((str_has_prefix(str, "onmatch(")) || + (str_has_prefix(str, "onmax("))) { attrs->action_str[attrs->n_actions] = kstrdup(str, GFP_KERNEL); if (!attrs->action_str[attrs->n_actions]) { ret = -ENOMEM; @@ -1896,34 +1896,34 @@ static int parse_assignment(char *str, struct hist_trigger_attrs *attrs) { int ret = 0; - if ((strncmp(str, "key=", strlen("key=")) == 0) || - (strncmp(str, "keys=", strlen("keys=")) == 0)) { + if ((str_has_prefix(str, "key=")) || + (str_has_prefix(str, "keys="))) { attrs->keys_str = kstrdup(str, GFP_KERNEL); if (!attrs->keys_str) { ret = -ENOMEM; goto out; } - } else if ((strncmp(str, "val=", strlen("val=")) == 0) || - (strncmp(str, "vals=", strlen("vals=")) == 0) || - (strncmp(str, "values=", strlen("values=")) == 0)) { + } else if ((str_has_prefix(str, "val=")) || + (str_has_prefix(str, "vals=")) || + (str_has_prefix(str, "values="))) { attrs->vals_str = kstrdup(str, GFP_KERNEL); if (!attrs->vals_str) { ret = -ENOMEM; goto out; } - } else if (strncmp(str, "sort=", strlen("sort=")) == 0) { + } else if (str_has_prefix(str, "sort=")) { attrs->sort_key_str = kstrdup(str, GFP_KERNEL); if (!attrs->sort_key_str) { ret = -ENOMEM; goto out; } - } else if (strncmp(str, "name=", strlen("name=")) == 0) { + } else if (str_has_prefix(str, "name=")) { attrs->name = kstrdup(str, GFP_KERNEL); if (!attrs->name) { ret = -ENOMEM; goto out; } - } else if (strncmp(str, "clock=", strlen("clock=")) == 0) { + } else if (str_has_prefix(str, "clock=")) { strsep(&str, "="); if (!str) { ret = -EINVAL; @@ -1936,7 +1936,7 @@ static int parse_assignment(char *str, struct hist_trigger_attrs *attrs) ret = -ENOMEM; goto out; } - } else if (strncmp(str, "size=", strlen("size=")) == 0) { + } else if (str_has_prefix(str, "size=")) { int map_bits = parse_map_size(str); if (map_bits < 0) { @@ -3623,7 +3623,7 @@ static struct action_data *onmax_parse(char *str) if (!onmax_fn_name || !str) goto free; - if (strncmp(onmax_fn_name, "save", strlen("save")) == 0) { + if (str_has_prefix(onmax_fn_name, "save")) { char *params = strsep(&str, ")"); if (!params) { @@ -4414,8 +4414,8 @@ static int parse_actions(struct hist_trigger_data *hist_data) for (i = 0; i < hist_data->attrs->n_actions; i++) { str = hist_data->attrs->action_str[i]; - if (strncmp(str, "onmatch(", strlen("onmatch(")) == 0) { - char *action_str = str + strlen("onmatch("); + if (str_has_prefix(str, "onmatch(")) { + char *action_str = str + sizeof("onmatch(") - 1; data = onmatch_parse(tr, action_str); if (IS_ERR(data)) { @@ -4423,8 +4423,8 @@ static int parse_actions(struct hist_trigger_data *hist_data) break; } data->fn = action_trace; - } else if (strncmp(str, "onmax(", strlen("onmax(")) == 0) { - char *action_str = str + strlen("onmax("); + } else if (str_has_prefix(str, "onmax(")) { + char *action_str = str + sizeof("onmax(") - 1; data = onmax_parse(action_str); if (IS_ERR(data)) { -- 2.34.1