diff options
Diffstat (limited to 'drivers/hwtracing')
-rw-r--r-- | drivers/hwtracing/coresight/coresight-tmc-etr.c | 29 |
1 files changed, 24 insertions, 5 deletions
diff --git a/drivers/hwtracing/coresight/coresight-tmc-etr.c b/drivers/hwtracing/coresight/coresight-tmc-etr.c index bae47272de98..625882bc8b08 100644 --- a/drivers/hwtracing/coresight/coresight-tmc-etr.c +++ b/drivers/hwtracing/coresight/coresight-tmc-etr.c @@ -1418,10 +1418,11 @@ free_etr_perf_buffer: * buffer to the perf ring buffer. */ static void tmc_etr_sync_perf_buffer(struct etr_perf_buffer *etr_perf, + unsigned long src_offset, unsigned long to_copy) { long bytes; - long pg_idx, pg_offset, src_offset; + long pg_idx, pg_offset; unsigned long head = etr_perf->head; char **dst_pages, *src_buf; struct etr_buf *etr_buf = etr_perf->etr_buf; @@ -1430,7 +1431,6 @@ static void tmc_etr_sync_perf_buffer(struct etr_perf_buffer *etr_perf, pg_idx = head >> PAGE_SHIFT; pg_offset = head & (PAGE_SIZE - 1); dst_pages = (char **)etr_perf->pages; - src_offset = etr_buf->offset + etr_buf->len - to_copy; while (to_copy > 0) { /* @@ -1478,7 +1478,7 @@ tmc_update_etr_buffer(struct coresight_device *csdev, void *config) { bool lost = false; - unsigned long flags, size = 0; + unsigned long flags, offset, size = 0; struct tmc_drvdata *drvdata = dev_get_drvdata(csdev->dev.parent); struct etr_perf_buffer *etr_perf = config; struct etr_buf *etr_buf = etr_perf->etr_buf; @@ -1506,16 +1506,35 @@ tmc_update_etr_buffer(struct coresight_device *csdev, spin_unlock_irqrestore(&drvdata->spinlock, flags); lost = etr_buf->full; + offset = etr_buf->offset; size = etr_buf->len; + + /* + * The ETR buffer may be bigger than the space available in the + * perf ring buffer (handle->size). If so advance the offset so that we + * get the latest trace data. In snapshot mode none of that matters + * since we are expected to clobber stale data in favour of the latest + * traces. + */ if (!etr_perf->snapshot && size > handle->size) { - size = handle->size; + u32 mask = tmc_get_memwidth_mask(drvdata); + + /* + * Make sure the new size is aligned in accordance with the + * requirement explained in function tmc_get_memwidth_mask(). + */ + size = handle->size & mask; + offset = etr_buf->offset + etr_buf->len - size; + + if (offset >= etr_buf->size) + offset -= etr_buf->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); + tmc_etr_sync_perf_buffer(etr_perf, offset, size); /* * In snapshot mode we simply increment the head by the number of byte |