diff mbox

spi: add transfer histogram statistics via sysfs

Message ID 1434978124-2396-1-git-send-email-kernel@martin.sperl.org (mailing list archive)
State Accepted
Commit 6b7bc0618ff1a333d2265131b124e966335d5dee
Headers show

Commit Message

Martin Sperl June 22, 2015, 1:02 p.m. UTC 
From: Martin Sperl <kernel@martin.sperl.org>

report transfer sizes as a histogram via the following files:
  /sys/class/spi_master/spi*/statistics/transfer_bytes_histo_*
  /sys/class/spi_master/spi*/spi*.*/statistics/transfer_bytes_histo_*

Signed-off-by: Martin Sperl <kernel@martin.sperl.org>
---
 drivers/spi/spi.c       |   61 +++++++++++++++++++++++++++++++++++++++++++++++
 include/linux/spi/spi.h |    4 ++++
 2 files changed, 65 insertions(+)

This is an optional patch that exports those histogram values via sysfs.
Investigation into exporting these via debugfs as an alternative is ongoing.

Requires the basic statistics patch applied.
diff mbox

Patch

diff --git a/drivers/spi/spi.c b/drivers/spi/spi.c
index 07476ca..2fb4d72 100644
--- a/drivers/spi/spi.c
+++ b/drivers/spi/spi.c
@@ -123,6 +123,28 @@  SPI_STATISTICS_SHOW(bytes, "%llu");
 SPI_STATISTICS_SHOW(bytes_rx, "%llu");
 SPI_STATISTICS_SHOW(bytes_tx, "%llu");
 
+#define SPI_STATISTICS_TRANSFER_BYTES_HISTO(index, number)		\
+	SPI_STATISTICS_SHOW_NAME(transfer_bytes_histo##index,		\
+				 "transfer_bytes_histo_" number,	\
+				 transfer_bytes_histo[index],  "%lu")
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(0,  "0-1");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(1,  "2-3");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(2,  "4-7");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(3,  "8-15");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(4,  "16-31");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(5,  "32-63");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(6,  "64-127");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(7,  "128-255");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(8,  "256-511");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(9,  "512-1023");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(10, "1024-2047");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(11, "2048-4095");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(12, "4096-8191");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(13, "8192-16383");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(14, "16384-32767");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(15, "32768-65535");
+SPI_STATISTICS_TRANSFER_BYTES_HISTO(16, "65536+");
+
 static struct attribute *spi_dev_attrs[] = {
 	&dev_attr_modalias.attr,
 	NULL,
@@ -143,6 +165,23 @@  static struct attribute *spi_device_statistics_attrs[] = {
 	&dev_attr_spi_device_bytes.attr,
 	&dev_attr_spi_device_bytes_rx.attr,
 	&dev_attr_spi_device_bytes_tx.attr,
+	&dev_attr_spi_device_transfer_bytes_histo0.attr,
+	&dev_attr_spi_device_transfer_bytes_histo1.attr,
+	&dev_attr_spi_device_transfer_bytes_histo2.attr,
+	&dev_attr_spi_device_transfer_bytes_histo3.attr,
+	&dev_attr_spi_device_transfer_bytes_histo4.attr,
+	&dev_attr_spi_device_transfer_bytes_histo5.attr,
+	&dev_attr_spi_device_transfer_bytes_histo6.attr,
+	&dev_attr_spi_device_transfer_bytes_histo7.attr,
+	&dev_attr_spi_device_transfer_bytes_histo8.attr,
+	&dev_attr_spi_device_transfer_bytes_histo9.attr,
+	&dev_attr_spi_device_transfer_bytes_histo10.attr,
+	&dev_attr_spi_device_transfer_bytes_histo11.attr,
+	&dev_attr_spi_device_transfer_bytes_histo12.attr,
+	&dev_attr_spi_device_transfer_bytes_histo13.attr,
+	&dev_attr_spi_device_transfer_bytes_histo14.attr,
+	&dev_attr_spi_device_transfer_bytes_histo15.attr,
+	&dev_attr_spi_device_transfer_bytes_histo16.attr,
 	NULL,
 };
 
@@ -168,6 +207,23 @@  static struct attribute *spi_master_statistics_attrs[] = {
 	&dev_attr_spi_master_bytes.attr,
 	&dev_attr_spi_master_bytes_rx.attr,
 	&dev_attr_spi_master_bytes_tx.attr,
+	&dev_attr_spi_master_transfer_bytes_histo0.attr,
+	&dev_attr_spi_master_transfer_bytes_histo1.attr,
+	&dev_attr_spi_master_transfer_bytes_histo2.attr,
+	&dev_attr_spi_master_transfer_bytes_histo3.attr,
+	&dev_attr_spi_master_transfer_bytes_histo4.attr,
+	&dev_attr_spi_master_transfer_bytes_histo5.attr,
+	&dev_attr_spi_master_transfer_bytes_histo6.attr,
+	&dev_attr_spi_master_transfer_bytes_histo7.attr,
+	&dev_attr_spi_master_transfer_bytes_histo8.attr,
+	&dev_attr_spi_master_transfer_bytes_histo9.attr,
+	&dev_attr_spi_master_transfer_bytes_histo10.attr,
+	&dev_attr_spi_master_transfer_bytes_histo11.attr,
+	&dev_attr_spi_master_transfer_bytes_histo12.attr,
+	&dev_attr_spi_master_transfer_bytes_histo13.attr,
+	&dev_attr_spi_master_transfer_bytes_histo14.attr,
+	&dev_attr_spi_master_transfer_bytes_histo15.attr,
+	&dev_attr_spi_master_transfer_bytes_histo16.attr,
 	NULL,
 };
 
@@ -186,10 +242,15 @@  void spi_statistics_add_transfer_stats(struct spi_statistics *stats,
 				       struct spi_master *master)
 {
 	unsigned long flags;
+	int l2len = min(fls(xfer->len), SPI_STATISTICS_HISTO_SIZE) - 1;
+
+	if (l2len < 0)
+		l2len = 0;
 
 	spin_lock_irqsave(&stats->lock, flags);
 
 	stats->transfers++;
+	stats->transfer_bytes_histo[l2len]++;
 
 	stats->bytes += xfer->len;
 	if ((xfer->tx_buf) &&
diff --git a/include/linux/spi/spi.h b/include/linux/spi/spi.h
index 269e8af..5b6fdc4 100644
--- a/include/linux/spi/spi.h
+++ b/include/linux/spi/spi.h
@@ -51,6 +51,8 @@  extern struct bus_type spi_bus_type;
  * @bytes_tx:      number of bytes sent to device
  * @bytes_rx:      number of bytes received from device
  *
+ * @transfer_bytes_histo:
+ *                 transfer bytes histogramm
  */
 struct spi_statistics {
 	spinlock_t		lock; /* lock for the whole structure */
@@ -68,6 +70,8 @@  struct spi_statistics {
 	unsigned long long	bytes_rx;
 	unsigned long long	bytes_tx;
 
+#define SPI_STATISTICS_HISTO_SIZE 17
+	unsigned long transfer_bytes_histo[SPI_STATISTICS_HISTO_SIZE];
 };
 
 void spi_statistics_add_transfer_stats(struct spi_statistics *stats,