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From: Tao Zhang <quic_taozha@quicinc.com>
To: Mathieu Poirier <mathieu.poirier@linaro.org>,
        Suzuki K Poulose
	<suzuki.poulose@arm.com>,
        Alexander Shishkin
	<alexander.shishkin@linux.intel.com>,
        Konrad Dybcio <konradybcio@gmail.com>,
        Mike Leach <mike.leach@linaro.org>, Rob Herring <robh+dt@kernel.org>,
        Krzysztof Kozlowski <krzysztof.kozlowski+dt@linaro.org>
CC: Tao Zhang <quic_taozha@quicinc.com>,
        Jinlong Mao
	<quic_jinlmao@quicinc.com>, Leo Yan <leo.yan@linaro.org>,
        Greg Kroah-Hartman
	<gregkh@linuxfoundation.org>,
        <coresight@lists.linaro.org>, <linux-arm-kernel@lists.infradead.org>,
        <linux-kernel@vger.kernel.org>, <devicetree@vger.kernel.org>,
        Tingwei Zhang <quic_tingweiz@quicinc.com>,
        Yuanfang Zhang <quic_yuanfang@quicinc.com>,
        Trilok Soni
	<quic_tsoni@quicinc.com>,
        Song Chai <quic_songchai@quicinc.com>, <linux-arm-msm@vger.kernel.org>,
        <andersson@kernel.org>
Subject: [PATCH v4 01/10] coresight-tpdm: Optimize the store function of tpdm simple dataset
Date: Fri, 19 Jan 2024 11:22:54 +0800
Message-ID: <1705634583-17631-2-git-send-email-quic_taozha@quicinc.com>
In-Reply-To: <1705634583-17631-1-git-send-email-quic_taozha@quicinc.com>
References: <1705634583-17631-1-git-send-email-quic_taozha@quicinc.com>
Precedence: bulk
MIME-Version: 1.0
Content-Type: text/plain

Replace spin lock/unlock to avoid forgetting to unlock when the
function exits. And refine methods for handling various conditions.

Signed-off-by: Tao Zhang <quic_taozha@quicinc.com>
---
 drivers/hwtracing/coresight/coresight-tpdm.c | 39 ++++++++++----------
 1 file changed, 19 insertions(+), 20 deletions(-)

diff --git a/drivers/hwtracing/coresight/coresight-tpdm.c b/drivers/hwtracing/coresight/coresight-tpdm.c
index bd13a548375c..0427c0fc0bf3 100644
--- a/drivers/hwtracing/coresight/coresight-tpdm.c
+++ b/drivers/hwtracing/coresight/coresight-tpdm.c
@@ -77,51 +77,50 @@ static ssize_t tpdm_simple_dataset_store(struct device *dev,
 					 size_t size)
 {
 	unsigned long val;
-	ssize_t ret = size;
+	ssize_t ret = -EINVAL;
 
 	struct tpdm_drvdata *drvdata = dev_get_drvdata(dev->parent);
 	struct tpdm_dataset_attribute *tpdm_attr =
 		container_of(attr, struct tpdm_dataset_attribute, attr);
 
 	if (kstrtoul(buf, 0, &val))
-		return -EINVAL;
+		return ret;
 
-	spin_lock(&drvdata->spinlock);
+	guard(spinlock)(&drvdata->spinlock);
 	switch (tpdm_attr->mem) {
 	case DSB_TRIG_PATT:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->trig_patt[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_TRIG_PATT_MASK:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->trig_patt_mask[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_PATT:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->patt_val[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_PATT_MASK:
-		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT)
+		if (tpdm_attr->idx < TPDM_DSB_MAX_PATT) {
 			drvdata->dsb->patt_mask[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	case DSB_MSR:
-		if (tpdm_attr->idx < drvdata->dsb_msr_num)
+		if (tpdm_attr->idx < drvdata->dsb_msr_num) {
 			drvdata->dsb->msr[tpdm_attr->idx] = val;
-		else
-			ret = -EINVAL;
+			ret = size;
+		}
 		break;
 	default:
-		ret = -EINVAL;
+		break;
 	}
-	spin_unlock(&drvdata->spinlock);
 
 	return ret;
 }
-- 
2.17.1