From 41c0e5b7a35392c90a467a9a085178642a131324 Mon Sep 17 00:00:00 2001 From: Suzuki K Poulose Date: Tue, 19 Oct 2021 17:31:43 +0100 Subject: coresight: trbe: Add a helper to calculate the trace generated We collect the trace from the TRBE on FILL event from IRQ context and via update_buffer(), when the event is stopped. Let us consolidate how we calculate the trace generated into a helper. Cc: Mathieu Poirier Cc: Mike Leach Cc: Leo Yan Reviewed-by: Anshuman Khandual Signed-off-by: Suzuki K Poulose Link: https://lore.kernel.org/r/20211019163153.3692640-6-suzuki.poulose@arm.com Signed-off-by: Mathieu Poirier --- drivers/hwtracing/coresight/coresight-trbe.c | 47 +++++++++++++++++----------- 1 file changed, 29 insertions(+), 18 deletions(-) (limited to 'drivers/hwtracing') diff --git a/drivers/hwtracing/coresight/coresight-trbe.c b/drivers/hwtracing/coresight/coresight-trbe.c index 5d77baba8b0f..54f5d61ee9fb 100644 --- a/drivers/hwtracing/coresight/coresight-trbe.c +++ b/drivers/hwtracing/coresight/coresight-trbe.c @@ -499,6 +499,29 @@ static enum trbe_fault_action trbe_get_fault_act(u64 trbsr) return TRBE_FAULT_ACT_SPURIOUS; } +static unsigned long trbe_get_trace_size(struct perf_output_handle *handle, + struct trbe_buf *buf, bool wrap) +{ + u64 write; + u64 start_off, end_off; + + /* + * If the TRBE has wrapped around the write pointer has + * wrapped and should be treated as limit. + */ + if (wrap) + write = get_trbe_limit_pointer(); + else + write = get_trbe_write_pointer(); + + end_off = write - get_trbe_base_pointer(); + start_off = PERF_IDX2OFF(handle->head, buf); + + if (WARN_ON_ONCE(end_off < start_off)) + return 0; + return (end_off - start_off); +} + static void *arm_trbe_alloc_buffer(struct coresight_device *csdev, struct perf_event *event, void **pages, int nr_pages, bool snapshot) @@ -560,9 +583,9 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, struct trbe_cpudata *cpudata = dev_get_drvdata(&csdev->dev); struct trbe_buf *buf = config; enum trbe_fault_action act; - unsigned long size, offset; - unsigned long write, base, status; + unsigned long size, status; unsigned long flags; + bool wrap = false; WARN_ON(buf->cpudata != cpudata); WARN_ON(cpudata->cpu != smp_processor_id()); @@ -602,8 +625,6 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, * handle gets freed in etm_event_stop(). */ trbe_drain_and_disable_local(); - write = get_trbe_write_pointer(); - base = get_trbe_base_pointer(); /* Check if there is a pending interrupt and handle it here */ status = read_sysreg_s(SYS_TRBSR_EL1); @@ -627,20 +648,11 @@ static unsigned long arm_trbe_update_buffer(struct coresight_device *csdev, goto done; } - /* - * Otherwise, the buffer is full and the write pointer - * has reached base. Adjust this back to the Limit pointer - * for correct size. Also, mark the buffer truncated. - */ - write = get_trbe_limit_pointer(); trbe_report_wrap_event(handle); + wrap = true; } - offset = write - base; - if (WARN_ON_ONCE(offset < PERF_IDX2OFF(handle->head, buf))) - size = 0; - else - size = offset - PERF_IDX2OFF(handle->head, buf); + size = trbe_get_trace_size(handle, buf, wrap); done: local_irq_restore(flags); @@ -721,11 +733,10 @@ static int trbe_handle_overflow(struct perf_output_handle *handle) { struct perf_event *event = handle->event; struct trbe_buf *buf = etm_perf_sink_config(handle); - unsigned long offset, size; + unsigned long size; struct etm_event_data *event_data; - offset = get_trbe_limit_pointer() - get_trbe_base_pointer(); - size = offset - PERF_IDX2OFF(handle->head, buf); + size = trbe_get_trace_size(handle, buf, true); if (buf->snapshot) handle->head += size; -- cgit v1.2.3