From: Théo Lebrun theo.lebrun@bootlin.com
[ Upstream commit e63aef9c9121e5061cbf5112d12cadc9da399692 ]
Current behavior is that spi-mem operations do not increment statistics, neither per-controller nor per-device, if ->exec_op() is used. For operations that do NOT use ->exec_op(), stats are increased as the usual spi_sync() is called.
The newly implemented spi_mem_add_op_stats() function is strongly inspired by spi_statistics_add_transfer_stats(); locking logic and l2len computation comes from there.
Statistics that are being filled: bytes{,_rx,_tx}, messages, transfers, errors, timedout, transfer_bytes_histo_*.
Note about messages & transfers counters: in the fallback to spi_sync() case, there are from 1 to 4 transfers per message. We only register one big transfer in the ->exec_op() case as that is closer to reality.
This patch is NOT touching: - spi_async, spi_sync, spi_sync_immediate: those counters describe precise function calls, incrementing them would be lying. I believe comparing the messages counter to spi_async+spi_sync is a good way to detect ->exec_op() calls, but I might be missing edge cases knowledge. - transfers_split_maxsize: splitting cannot happen if ->exec_op() is provided.
Reviewed-by: Dhruva Gole d-gole@ti.com Signed-off-by: Théo Lebrun theo.lebrun@bootlin.com Reviewed-by: Tudor Ambarus tudor.ambarus@linaro.org Link: https://msgid.link/r/20240216-spi-mem-stats-v2-1-9256dfe4887d@bootlin.com Signed-off-by: Mark Brown broonie@kernel.org Stable-dep-of: 29895ce18311 ("spi: Fix error code checking in spi_mem_exec_op()") Signed-off-by: Sasha Levin sashal@kernel.org --- drivers/spi/spi-mem.c | 49 ++++++++++++++++++++++++++++++++++++++++++- 1 file changed, 48 insertions(+), 1 deletion(-)
diff --git a/drivers/spi/spi-mem.c b/drivers/spi/spi-mem.c index 2dc8ceb85374b..c9d6d42a88f55 100644 --- a/drivers/spi/spi-mem.c +++ b/drivers/spi/spi-mem.c @@ -297,6 +297,49 @@ static void spi_mem_access_end(struct spi_mem *mem) pm_runtime_put(ctlr->dev.parent); }
+static void spi_mem_add_op_stats(struct spi_statistics __percpu *pcpu_stats, + const struct spi_mem_op *op, int exec_op_ret) +{ + struct spi_statistics *stats; + u64 len, l2len; + + get_cpu(); + stats = this_cpu_ptr(pcpu_stats); + u64_stats_update_begin(&stats->syncp); + + /* + * We do not have the concept of messages or transfers. Let's consider + * that one operation is equivalent to one message and one transfer. + */ + u64_stats_inc(&stats->messages); + u64_stats_inc(&stats->transfers); + + /* Use the sum of all lengths as bytes count and histogram value. */ + len = op->cmd.nbytes + op->addr.nbytes; + len += op->dummy.nbytes + op->data.nbytes; + u64_stats_add(&stats->bytes, len); + l2len = min(fls(len), SPI_STATISTICS_HISTO_SIZE) - 1; + u64_stats_inc(&stats->transfer_bytes_histo[l2len]); + + /* Only account for data bytes as transferred bytes. */ + if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_OUT) + u64_stats_add(&stats->bytes_tx, op->data.nbytes); + if (op->data.nbytes && op->data.dir == SPI_MEM_DATA_IN) + u64_stats_add(&stats->bytes_rx, op->data.nbytes); + + /* + * A timeout is not an error, following the same behavior as + * spi_transfer_one_message(). + */ + if (exec_op_ret == -ETIMEDOUT) + u64_stats_inc(&stats->timedout); + else if (exec_op_ret) + u64_stats_inc(&stats->errors); + + u64_stats_update_end(&stats->syncp); + put_cpu(); +} + /** * spi_mem_exec_op() - Execute a memory operation * @mem: the SPI memory @@ -339,8 +382,12 @@ int spi_mem_exec_op(struct spi_mem *mem, const struct spi_mem_op *op) * read path) and expect the core to use the regular SPI * interface in other cases. */ - if (!ret || ret != -ENOTSUPP || ret != -EOPNOTSUPP) + if (!ret || ret != -ENOTSUPP || ret != -EOPNOTSUPP) { + spi_mem_add_op_stats(ctlr->pcpu_statistics, op, ret); + spi_mem_add_op_stats(mem->spi->pcpu_statistics, op, ret); + return ret; + } }
tmpbufsize = op->cmd.nbytes + op->addr.nbytes + op->dummy.nbytes;