From 319acdbf1d958e522ffce60b135f1c6d8acabade Mon Sep 17 00:00:00 2001 From: Mathieu Poirier Date: Thu, 29 Aug 2019 14:28:41 -0600 Subject: [PATCH] UPSTREAM: coresight: tmc-etr: Decouple buffer sync and barrier packet insertion (Upstream commit 3507d231a499e27c4bac8a47169b74ec7ef87292). If less space is available in the perf ring buffer than the ETR buffer, barrier packets inserted in the trace stream by tmc_sync_etr_buf() are skipped over when the head of the buffer is moved forward, resulting in traces that can't be decoded. This patch decouples the process of syncing ETR buffers and the addition of barrier packets in order to perform the latter once the offset in the trace buffer has been properly computed. Signed-off-by: Mathieu Poirier Reviewed-by: Leo Yan Link: https://lore.kernel.org/r/20190829202842.580-17-mathieu.poirier@linaro.org Signed-off-by: Greg Kroah-Hartman Bug: 140266694 Change-Id: I2ecf6cdb2cde8180adc4ccd06e7916c89416c629 Signed-off-by: Yabin Cui --- .../hwtracing/coresight/coresight-tmc-etr.c | 18 ++++++++++++------ 1 file changed, 12 insertions(+), 6 deletions(-) diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index 8b0c1ba9ff83..f61478fcb617 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -938,10 +938,6 @@ static void tmc_sync_etr_buf(struct tmc_drvdata *drvdata) WARN_ON(!etr_buf->ops || !etr_buf->ops->sync); etr_buf->ops->sync(etr_buf, rrp, rwp); - - /* Insert barrier packets at the beginning, if there was an overflow */ - if (etr_buf->full) - tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset); } static void __tmc_etr_enable_hw(struct tmc_drvdata *drvdata) @@ -1078,6 +1074,13 @@ static void tmc_etr_sync_sysfs_buf(struct tmc_drvdata *drvdata) drvdata->sysfs_buf = NULL; } else { tmc_sync_etr_buf(drvdata); + /* + * Insert barrier packets at the beginning, if there was + * an overflow. + */ + if (etr_buf->full) + tmc_etr_buf_insert_barrier_packet(etr_buf, + etr_buf->offset); } } @@ -1494,11 +1497,16 @@ tmc_update_etr_buffer(struct coresight_device *csdev, CS_LOCK(drvdata->base); spin_unlock_irqrestore(&drvdata->spinlock, flags); + lost = etr_buf->full; size = etr_buf->len; if (!etr_perf->snapshot && size > handle->size) { size = handle->size; lost = true; } + + /* Insert barrier packets at the beginning, if there was an overflow */ + if (lost) + tmc_etr_buf_insert_barrier_packet(etr_buf, etr_buf->offset); tmc_etr_sync_perf_buffer(etr_perf, size); /* @@ -1509,8 +1517,6 @@ tmc_update_etr_buffer(struct coresight_device *csdev, */ if (etr_perf->snapshot) handle->head += size; - - lost |= etr_buf->full; out: /* * Don't set the TRUNCATED flag in snapshot mode because 1) the