From 3507d231a499e27c4bac8a47169b74ec7ef87292 Mon Sep 17 00:00:00 2001 From: Mathieu Poirier Date: Thu, 29 Aug 2019 14:28:41 -0600 Subject: [PATCH] coresight: tmc-etr: Decouple buffer sync and barrier packet insertion 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 --- .../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 4f000a03152e..bae47272de98 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -946,10 +946,6 @@ 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) @@ -1086,6 +1082,13 @@ 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); } } @@ -1502,11 +1505,16 @@ 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); /* @@ -1517,8 +1525,6 @@ 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