Merge "coresight: tmc-etr: Fix deadlock issue while reading from ETR" (e10b49be) · Commits · e / devices / android_kernel_fairphone_FP5

drivers/hwtracing/coresight/coresight-tmc-etr.c

+9 −5

Original line number	Diff line number	Diff line
		@@ -2165,14 +2165,18 @@ int tmc_read_prepare_etr(struct tmc_drvdata *drvdata)
		goto out;
		}

		drvdata->reading = true;

		/* Disable the TMC if we are trying to read from a running session. */
		if (drvdata->mode == CS_MODE_SYSFS) {
		spin_unlock_irqrestore(&drvdata->spinlock, flags);
		mutex_unlock(&drvdata->mem_lock);
		coresight_disable_all_source_link();
		mutex_lock(&drvdata->mem_lock);
		spin_lock_irqsave(&drvdata->spinlock, flags);
		__tmc_etr_disable_hw(drvdata);
		}
		drvdata->reading = true;

		out:
		spin_unlock_irqrestore(&drvdata->spinlock, flags);
		mutex_unlock(&drvdata->mem_lock);
		@@ -2200,10 +2204,6 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
		* be NULL.
		*/
		__tmc_etr_enable_hw(drvdata);

		spin_unlock_irqrestore(&drvdata->spinlock, flags);
		coresight_enable_all_source_link();
		spin_lock_irqsave(&drvdata->spinlock, flags);
		} else {
		/*
		* The ETR is not tracing and the buffer was just read.
		@@ -2220,5 +2220,9 @@ int tmc_read_unprepare_etr(struct tmc_drvdata *drvdata)
		tmc_etr_free_sysfs_buf(sysfs_buf);

		mutex_unlock(&drvdata->mem_lock);

		if (drvdata->mode == CS_MODE_SYSFS)
		coresight_enable_all_source_link();

		return 0;
		}