* [PATCH v5 1/3] dmaengine: Add basic debugfs support
2020-03-06 14:28 [PATCH v5 0/3] dmaengine: Initial debugfs support Peter Ujfalusi
@ 2020-03-06 14:28 ` Peter Ujfalusi
2020-03-06 14:28 ` [PATCH v5 2/3] dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs Peter Ujfalusi
` (2 subsequent siblings)
3 siblings, 0 replies; 5+ messages in thread
From: Peter Ujfalusi @ 2020-03-06 14:28 UTC (permalink / raw)
To: vkoul; +Cc: dmaengine, linux-kernel, dan.j.williams, geert
Via the /sys/kernel/debug/dmaengine/summary users can get information
about the DMA devices and the used channels.
Example output on am654-evm with audio using two channels and after running
dmatest on 4 channels:
dma0 (285c0000.dma-controller): number of channels: 96
dma1 (31150000.dma-controller): number of channels: 267
dma1chan0 | 2b00000.mcasp:tx
dma1chan1 | 2b00000.mcasp:rx
dma1chan2 | in-use
dma1chan3 | in-use
dma1chan4 | in-use
dma1chan5 | in-use
For slave channels we can show the device and the channel name a given
channel is requested.
For non slave devices the only information we know is that the channel is
in use.
DMA drivers can implement the optional dbg_summary_show callback to
provide controller specific information instead of the generic one.
It is easy to extend the generic dmaengine_summary_show() to print
additional information about the used channels.
I have taken the idea from gpiolib and clk subsystems.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
drivers/dma/dmaengine.c | 76 ++++++++++++++++++++++++++++++++++++++-
include/linux/dmaengine.h | 13 ++++++-
2 files changed, 87 insertions(+), 2 deletions(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index c3b1283b6d31..509abc8e8378 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -58,6 +58,65 @@ static DEFINE_IDA(dma_ida);
static LIST_HEAD(dma_device_list);
static long dmaengine_ref_count;
+/* --- debugfs implementation --- */
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static void dmaengine_dbg_summary_show(struct seq_file *s,
+ struct dma_device *dma_dev)
+{
+ struct dma_chan *chan;
+
+ list_for_each_entry(chan, &dma_dev->channels, device_node) {
+ if (chan->client_count) {
+ seq_printf(s, " %-13s| %s", dma_chan_name(chan),
+ chan->dbg_client_name ?: "in-use");
+
+ if (chan->router)
+ seq_printf(s, " (via router: %s)\n",
+ dev_name(chan->router->dev));
+ else
+ seq_puts(s, "\n");
+ }
+ }
+}
+
+static int dmaengine_summary_show(struct seq_file *s, void *data)
+{
+ struct dma_device *dma_dev = NULL;
+
+ mutex_lock(&dma_list_mutex);
+ list_for_each_entry(dma_dev, &dma_device_list, global_node) {
+ seq_printf(s, "dma%d (%s): number of channels: %u\n",
+ dma_dev->dev_id, dev_name(dma_dev->dev),
+ dma_dev->chancnt);
+
+ if (dma_dev->dbg_summary_show)
+ dma_dev->dbg_summary_show(s, dma_dev);
+ else
+ dmaengine_dbg_summary_show(s, dma_dev);
+
+ if (!list_is_last(&dma_dev->global_node, &dma_device_list))
+ seq_puts(s, "\n");
+ }
+ mutex_unlock(&dma_list_mutex);
+
+ return 0;
+}
+DEFINE_SHOW_ATTRIBUTE(dmaengine_summary);
+
+static void __init dmaengine_debugfs_init(void)
+{
+ struct dentry *rootdir = debugfs_create_dir("dmaengine", NULL);
+
+ /* /sys/kernel/debug/dmaengine/summary */
+ debugfs_create_file("summary", 0444, rootdir, NULL,
+ &dmaengine_summary_fops);
+}
+#else
+static inline void dmaengine_debugfs_init(void) { }
+#endif /* DEBUG_FS */
+
/* --- sysfs implementation --- */
#define DMA_SLAVE_NAME "slave"
@@ -760,6 +819,11 @@ struct dma_chan *dma_request_chan(struct device *dev, const char *name)
return chan ? chan : ERR_PTR(-EPROBE_DEFER);
found:
+#ifdef CONFIG_DEBUG_FS
+ chan->dbg_client_name = kasprintf(GFP_KERNEL, "%s:%s", dev_name(dev),
+ name);
+#endif
+
chan->name = kasprintf(GFP_KERNEL, "dma:%s", name);
if (!chan->name)
return chan;
@@ -837,6 +901,11 @@ void dma_release_channel(struct dma_chan *chan)
chan->name = NULL;
chan->slave = NULL;
}
+
+#ifdef CONFIG_DEBUG_FS
+ kfree(chan->dbg_client_name);
+ chan->dbg_client_name = NULL;
+#endif
mutex_unlock(&dma_list_mutex);
}
EXPORT_SYMBOL_GPL(dma_release_channel);
@@ -1559,6 +1628,11 @@ static int __init dma_bus_init(void)
if (err)
return err;
- return class_register(&dma_devclass);
+
+ err = class_register(&dma_devclass);
+ if (!err)
+ dmaengine_debugfs_init();
+
+ return err;
}
arch_initcall(dma_bus_init);
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index d3672f065a64..72920b5cf2d7 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -300,6 +300,8 @@ struct dma_router {
* @chan_id: channel ID for sysfs
* @dev: class device for sysfs
* @name: backlink name for sysfs
+ * @dbg_client_name: slave name for debugfs in format:
+ * dev_name(requester's dev):channel name, for example: "2b00000.mcasp:tx"
* @device_node: used to add this to the device chan list
* @local: per-cpu pointer to a struct dma_chan_percpu
* @client_count: how many clients are using this channel
@@ -318,6 +320,9 @@ struct dma_chan {
int chan_id;
struct dma_chan_dev *dev;
const char *name;
+#ifdef CONFIG_DEBUG_FS
+ char *dbg_client_name;
+#endif
struct list_head device_node;
struct dma_chan_percpu __percpu *local;
@@ -806,7 +811,9 @@ struct dma_filter {
* called and there are no further references to this structure. This
* must be implemented to free resources however many existing drivers
* do not and are therefore not safe to unbind while in use.
- *
+ * @dbg_summary_show: optional routine to show contents in debugfs; default code
+ * will be used when this is omitted, but custom code can show extra,
+ * controller specific information.
*/
struct dma_device {
struct kref ref;
@@ -892,6 +899,10 @@ struct dma_device {
struct dma_tx_state *txstate);
void (*device_issue_pending)(struct dma_chan *chan);
void (*device_release)(struct dma_device *dev);
+ /* debugfs support */
+#ifdef CONFIG_DEBUG_FS
+ void (*dbg_summary_show)(struct seq_file *s, struct dma_device *dev);
+#endif
};
static inline int dmaengine_slave_config(struct dma_chan *chan,
--
Peter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v5 2/3] dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs
2020-03-06 14:28 [PATCH v5 0/3] dmaengine: Initial debugfs support Peter Ujfalusi
2020-03-06 14:28 ` [PATCH v5 1/3] dmaengine: Add basic " Peter Ujfalusi
@ 2020-03-06 14:28 ` Peter Ujfalusi
2020-03-06 14:28 ` [PATCH v5 3/3] dmaengine: Create debug directories for DMA devices Peter Ujfalusi
2020-03-11 9:26 ` [PATCH v5 0/3] dmaengine: Initial debugfs support Vinod Koul
3 siblings, 0 replies; 5+ messages in thread
From: Peter Ujfalusi @ 2020-03-06 14:28 UTC (permalink / raw)
To: vkoul; +Cc: dmaengine, linux-kernel, dan.j.williams, geert
With the custom dbg_summary_show the driver can show useful information
about the used channels.
dma0 (285c0000.dma-controller): number of channels: 24
dma1 (31150000.dma-controller): number of channels: 84
dma1chan0 | 2b00000.mcasp:tx (MEM_TO_DEV, tchan16 [0x1010 -> 0xc400], PDMA[ ACC32 BURST ], TR mode)
dma1chan1 | 2b00000.mcasp:rx (DEV_TO_MEM, rchan16 [0x4400 -> 0x9010], PDMA[ ACC32 BURST ], TR mode)
dma1chan2 | 2ba0000.mcasp:tx (MEM_TO_DEV, tchan17 [0x1011 -> 0xc507], PDMA[ ACC32 BURST ], TR mode)
dma1chan3 | 2ba0000.mcasp:rx (DEV_TO_MEM, rchan17 [0x4507 -> 0x9011], PDMA[ ACC32 BURST ], TR mode)
dma1chan4 | in-use (MEM_TO_MEM, chan0 pair [0x1000 -> 0x9000], PSI-L Native, TR mode)
dma1chan5 | in-use (MEM_TO_MEM, chan1 pair [0x1001 -> 0x9001], PSI-L Native, TR mode)
dma1chan6 | in-use (MEM_TO_MEM, chan4 pair [0x1004 -> 0x9004], PSI-L Native, TR mode)
dma1chan7 | in-use (MEM_TO_MEM, chan5 pair [0x1005 -> 0x9005], PSI-L Native, TR mode)
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
drivers/dma/ti/k3-udma.c | 63 ++++++++++++++++++++++++++++++++++++++++
1 file changed, 63 insertions(+)
diff --git a/drivers/dma/ti/k3-udma.c b/drivers/dma/ti/k3-udma.c
index 5e076e5680f4..a9c0251adf1a 100644
--- a/drivers/dma/ti/k3-udma.c
+++ b/drivers/dma/ti/k3-udma.c
@@ -3501,6 +3501,66 @@ static int udma_setup_rx_flush(struct udma_dev *ud)
return 0;
}
+#ifdef CONFIG_DEBUG_FS
+static void udma_dbg_summary_show_chan(struct seq_file *s,
+ struct dma_chan *chan)
+{
+ struct udma_chan *uc = to_udma_chan(chan);
+ struct udma_chan_config *ucc = &uc->config;
+
+ seq_printf(s, " %-13s| %s", dma_chan_name(chan),
+ chan->dbg_client_name ?: "in-use");
+ seq_printf(s, " (%s, ", dmaengine_get_direction_text(uc->config.dir));
+
+ switch (uc->config.dir) {
+ case DMA_MEM_TO_MEM:
+ seq_printf(s, "chan%d pair [0x%04x -> 0x%04x], ", uc->tchan->id,
+ ucc->src_thread, ucc->dst_thread);
+ break;
+ case DMA_DEV_TO_MEM:
+ seq_printf(s, "rchan%d [0x%04x -> 0x%04x], ", uc->rchan->id,
+ ucc->src_thread, ucc->dst_thread);
+ break;
+ case DMA_MEM_TO_DEV:
+ seq_printf(s, "tchan%d [0x%04x -> 0x%04x], ", uc->tchan->id,
+ ucc->src_thread, ucc->dst_thread);
+ break;
+ default:
+ seq_printf(s, ")\n");
+ return;
+ }
+
+ if (ucc->ep_type == PSIL_EP_NATIVE) {
+ seq_printf(s, "PSI-L Native");
+ if (ucc->metadata_size) {
+ seq_printf(s, "[%s", ucc->needs_epib ? " EPIB" : "");
+ if (ucc->psd_size)
+ seq_printf(s, " PSDsize:%u", ucc->psd_size);
+ seq_printf(s, " ]");
+ }
+ } else {
+ seq_printf(s, "PDMA");
+ if (ucc->enable_acc32 || ucc->enable_burst)
+ seq_printf(s, "[%s%s ]",
+ ucc->enable_acc32 ? " ACC32" : "",
+ ucc->enable_burst ? " BURST" : "");
+ }
+
+ seq_printf(s, ", %s)\n", ucc->pkt_mode ? "Packet mode" : "TR mode");
+}
+
+static void udma_dbg_summary_show(struct seq_file *s,
+ struct dma_device *dma_dev)
+{
+ struct dma_chan *chan;
+
+ list_for_each_entry(chan, &dma_dev->channels, device_node) {
+ if (chan->client_count)
+ udma_dbg_summary_show_chan(s, chan);
+ }
+}
+#endif /* CONFIG_DEBUG_FS */
+
#define TI_UDMAC_BUSWIDTHS (BIT(DMA_SLAVE_BUSWIDTH_1_BYTE) | \
BIT(DMA_SLAVE_BUSWIDTH_2_BYTES) | \
BIT(DMA_SLAVE_BUSWIDTH_3_BYTES) | \
@@ -3587,6 +3647,9 @@ static int udma_probe(struct platform_device *pdev)
ud->ddev.device_resume = udma_resume;
ud->ddev.device_terminate_all = udma_terminate_all;
ud->ddev.device_synchronize = udma_synchronize;
+#ifdef CONFIG_DEBUG_FS
+ ud->ddev.dbg_summary_show = udma_dbg_summary_show;
+#endif
ud->ddev.device_free_chan_resources = udma_free_chan_resources;
ud->ddev.src_addr_widths = TI_UDMAC_BUSWIDTHS;
--
Peter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
^ permalink raw reply related [flat|nested] 5+ messages in thread* [PATCH v5 3/3] dmaengine: Create debug directories for DMA devices
2020-03-06 14:28 [PATCH v5 0/3] dmaengine: Initial debugfs support Peter Ujfalusi
2020-03-06 14:28 ` [PATCH v5 1/3] dmaengine: Add basic " Peter Ujfalusi
2020-03-06 14:28 ` [PATCH v5 2/3] dmaengine: ti: k3-udma: Implement custom dbg_summary_show for debugfs Peter Ujfalusi
@ 2020-03-06 14:28 ` Peter Ujfalusi
2020-03-11 9:26 ` [PATCH v5 0/3] dmaengine: Initial debugfs support Vinod Koul
3 siblings, 0 replies; 5+ messages in thread
From: Peter Ujfalusi @ 2020-03-06 14:28 UTC (permalink / raw)
To: vkoul; +Cc: dmaengine, linux-kernel, dan.j.williams, geert
Create a placeholder directory for each registered DMA device.
DMA drivers can use the dmaengine_get_debugfs_root() call to get their
debugfs root and can populate with custom files to aim debugging.
Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
---
drivers/dma/dmaengine.c | 28 +++++++++++++++++++++++++++-
drivers/dma/dmaengine.h | 16 ++++++++++++++++
include/linux/dmaengine.h | 1 +
3 files changed, 44 insertions(+), 1 deletion(-)
diff --git a/drivers/dma/dmaengine.c b/drivers/dma/dmaengine.c
index 509abc8e8378..5a442752e07d 100644
--- a/drivers/dma/dmaengine.c
+++ b/drivers/dma/dmaengine.c
@@ -62,6 +62,22 @@ static long dmaengine_ref_count;
#ifdef CONFIG_DEBUG_FS
#include <linux/debugfs.h>
+static struct dentry *rootdir;
+
+static void dmaengine_debug_register(struct dma_device *dma_dev)
+{
+ dma_dev->dbg_dev_root = debugfs_create_dir(dev_name(dma_dev->dev),
+ rootdir);
+ if (IS_ERR(dma_dev->dbg_dev_root))
+ dma_dev->dbg_dev_root = NULL;
+}
+
+static void dmaengine_debug_unregister(struct dma_device *dma_dev)
+{
+ debugfs_remove_recursive(dma_dev->dbg_dev_root);
+ dma_dev->dbg_dev_root = NULL;
+}
+
static void dmaengine_dbg_summary_show(struct seq_file *s,
struct dma_device *dma_dev)
{
@@ -107,7 +123,7 @@ DEFINE_SHOW_ATTRIBUTE(dmaengine_summary);
static void __init dmaengine_debugfs_init(void)
{
- struct dentry *rootdir = debugfs_create_dir("dmaengine", NULL);
+ rootdir = debugfs_create_dir("dmaengine", NULL);
/* /sys/kernel/debug/dmaengine/summary */
debugfs_create_file("summary", 0444, rootdir, NULL,
@@ -115,6 +131,12 @@ static void __init dmaengine_debugfs_init(void)
}
#else
static inline void dmaengine_debugfs_init(void) { }
+static inline int dmaengine_debug_register(struct dma_device *dma_dev)
+{
+ return 0;
+}
+
+static inline void dmaengine_debug_unregister(struct dma_device *dma_dev) { }
#endif /* DEBUG_FS */
/* --- sysfs implementation --- */
@@ -1265,6 +1287,8 @@ int dma_async_device_register(struct dma_device *device)
dma_channel_rebalance();
mutex_unlock(&dma_list_mutex);
+ dmaengine_debug_register(device);
+
return 0;
err_out:
@@ -1298,6 +1322,8 @@ void dma_async_device_unregister(struct dma_device *device)
{
struct dma_chan *chan, *n;
+ dmaengine_debug_unregister(device);
+
list_for_each_entry_safe(chan, n, &device->channels, device_node)
__dma_async_device_channel_unregister(device, chan);
diff --git a/drivers/dma/dmaengine.h b/drivers/dma/dmaengine.h
index e8a320c9e57c..1bfbd64b1371 100644
--- a/drivers/dma/dmaengine.h
+++ b/drivers/dma/dmaengine.h
@@ -182,4 +182,20 @@ dmaengine_desc_callback_valid(struct dmaengine_desc_callback *cb)
struct dma_chan *dma_get_slave_channel(struct dma_chan *chan);
struct dma_chan *dma_get_any_slave_channel(struct dma_device *device);
+#ifdef CONFIG_DEBUG_FS
+#include <linux/debugfs.h>
+
+static inline struct dentry *
+dmaengine_get_debugfs_root(struct dma_device *dma_dev) {
+ return dma_dev->dbg_dev_root;
+}
+#else
+struct dentry;
+static inline struct dentry *
+dmaengine_get_debugfs_root(struct dma_device *dma_dev)
+{
+ return NULL;
+}
+#endif /* CONFIG_DEBUG_FS */
+
#endif
diff --git a/include/linux/dmaengine.h b/include/linux/dmaengine.h
index 72920b5cf2d7..21065c04c4ac 100644
--- a/include/linux/dmaengine.h
+++ b/include/linux/dmaengine.h
@@ -902,6 +902,7 @@ struct dma_device {
/* debugfs support */
#ifdef CONFIG_DEBUG_FS
void (*dbg_summary_show)(struct seq_file *s, struct dma_device *dev);
+ struct dentry *dbg_dev_root;
#endif
};
--
Peter
Texas Instruments Finland Oy, Porkkalankatu 22, 00180 Helsinki.
Y-tunnus/Business ID: 0615521-4. Kotipaikka/Domicile: Helsinki
^ permalink raw reply related [flat|nested] 5+ messages in thread* Re: [PATCH v5 0/3] dmaengine: Initial debugfs support
2020-03-06 14:28 [PATCH v5 0/3] dmaengine: Initial debugfs support Peter Ujfalusi
` (2 preceding siblings ...)
2020-03-06 14:28 ` [PATCH v5 3/3] dmaengine: Create debug directories for DMA devices Peter Ujfalusi
@ 2020-03-11 9:26 ` Vinod Koul
3 siblings, 0 replies; 5+ messages in thread
From: Vinod Koul @ 2020-03-11 9:26 UTC (permalink / raw)
To: Peter Ujfalusi; +Cc: dmaengine, linux-kernel, dan.j.williams, geert
On 06-03-20, 16:28, Peter Ujfalusi wrote:
> Hi,
>
> Changes sicne v4:
> - Move the dmaengine_debugfs_init() from late_initcall to be called from
> dma_bus_init to avoid races due to probe orders of drivers.
> - Separate patch to create DMA driver directories for debugfs
>
> Changes since v3:
> - Create a directory for dmaengine and name the initial file as summary
> - Function to get the debugfs root for DMA drivers if they want to place files
> - Custom dbg_summary_show implementation for k3-udma
>
> Changes since v2:
> - Use dma_chan_name() for printing the channel's name
>
> Changes since v1:
> - Use much more simplified fops for the debugfs file (via DEFINE_SHOW_ATTRIBUTE)
> - do not allow modification to dma_device_list while the debugfs file is read
> - rename the slave_name to dbg_client_name (it is only for debugging)
> - print information about dma_router if it is used by the channel
> - Formating of the output slightly changed
>
> The basic debugfs file (/sys/kernel/debug/dmaengine/summary) can be used to
> query basic information about the DMAengine usage (am654-evm):
>
> # cat /sys/kernel/debug/dmaengine/summary
> dma0 (285c0000.dma-controller): number of channels: 96
>
> dma1 (31150000.dma-controller): number of channels: 267
> dma1chan0 | 2b00000.mcasp:tx
> dma1chan1 | 2b00000.mcasp:rx
> dma1chan2 | in-use
> dma1chan3 | in-use
> dma1chan4 | in-use
> dma1chan5 | in-use
>
> Drivers can implement custom dbg_summary_show to add extended information via
> the summary file, like with the second patch for k3-udma (j721e-evm):
>
> # cat /sys/kernel/debug/dmaengine/summary
> dma0 (285c0000.dma-controller): number of channels: 24
>
> dma1 (31150000.dma-controller): number of channels: 84
> dma1chan0 | 2b00000.mcasp:tx (MEM_TO_DEV, tchan16 [0x1010 -> 0xc400], PDMA[ ACC32 BURST ], TR mode)
> dma1chan1 | 2b00000.mcasp:rx (DEV_TO_MEM, rchan16 [0x4400 -> 0x9010], PDMA[ ACC32 BURST ], TR mode)
> dma1chan2 | 2ba0000.mcasp:tx (MEM_TO_DEV, tchan17 [0x1011 -> 0xc507], PDMA[ ACC32 BURST ], TR mode)
> dma1chan3 | 2ba0000.mcasp:rx (DEV_TO_MEM, rchan17 [0x4507 -> 0x9011], PDMA[ ACC32 BURST ], TR mode)
> dma1chan4 | in-use (MEM_TO_MEM, chan0 pair [0x1000 -> 0x9000], PSI-L Native, TR mode)
> dma1chan5 | in-use (MEM_TO_MEM, chan1 pair [0x1001 -> 0x9001], PSI-L Native, TR mode)
> dma1chan6 | in-use (MEM_TO_MEM, chan4 pair [0x1004 -> 0x9004], PSI-L Native, TR mode)
> dma1chan7 | in-use (MEM_TO_MEM, chan5 pair [0x1005 -> 0x9005], PSI-L Native, TR mode)
>
> With the last patch the debugfs looks like this:
> # ls -al /sys/kernel/debug/dmaengine/
> total 0
> drwxr-xr-x 4 root root 0 Jan 1 02:00 .
> drwx------ 29 root root 0 Jan 1 02:00 ..
> drwxr-xr-x 2 root root 0 Jan 1 02:00 285c0000.dma-controller
> drwxr-xr-x 2 root root 0 Jan 1 02:00 31150000.dma-controller
> -r--r--r-- 1 root root 0 Jan 1 02:00 summary
Applied, thanks
--
~Vinod
^ permalink raw reply [flat|nested] 5+ messages in thread