@@ -15,17 +15,15 @@ be built as module or inside kernel. Let's consider those cases.
Part 2 - When dmatest is built as a module...
-After mounting debugfs and loading the module, the /sys/kernel/debug/dmatest
-folder with a file named 'run' nodes will be created. 'run' controls run and
-stop phases of the test.
-
-Note that in this case test will not run on load automatically.
-
Example of usage:
+ % modprobe dmatest channel=dma0chan0 timeout=2000 iterations=1 run=1
+
+...or:
+ % modprobe dmatest
% echo dma0chan0 > /sys/module/dmatest/parameters/channel
% echo 2000 > /sys/module/dmatest/parameters/timeout
% echo 1 > /sys/module/dmatest/parameters/iterations
- % echo 1 > /sys/kernel/debug/dmatest/run
+ % echo 1 > /sys/module/dmatest/parameters/run
Hint: available channel list could be extracted by running the following
command:
@@ -42,7 +40,7 @@ The following command should return actual state of the test.
To wait for test done the user may perform a busy loop that checks the state.
- % while [ $(cat /sys/kernel/debug/dmatest/run) = "Y" ]
+ % while [ $(cat /sys/module/dmatest/parameters/run) = "Y" ]
> do
> echo -n "."
> sleep 1
@@ -21,10 +21,6 @@
#include <linux/random.h>
#include <linux/slab.h>
#include <linux/wait.h>
-#include <linux/ctype.h>
-#include <linux/debugfs.h>
-#include <linux/uaccess.h>
-#include <linux/seq_file.h>
static unsigned int test_buf_size = 16384;
module_param(test_buf_size, uint, S_IRUGO | S_IWUSR);
@@ -70,45 +66,6 @@ module_param(timeout, uint, S_IRUGO | S_IWUSR);
MODULE_PARM_DESC(timeout, "Transfer Timeout in msec (default: 3000), "
"Pass -1 for infinite timeout");
-/* Maximum amount of mismatched bytes in buffer to print */
-#define MAX_ERROR_COUNT 32
-
-/*
- * Initialization patterns. All bytes in the source buffer has bit 7
- * set, all bytes in the destination buffer has bit 7 cleared.
- *
- * Bit 6 is set for all bytes which are to be copied by the DMA
- * engine. Bit 5 is set for all bytes which are to be overwritten by
- * the DMA engine.
- *
- * The remaining bits are the inverse of a counter which increments by
- * one for each byte address.
- */
-#define PATTERN_SRC 0x80
-#define PATTERN_DST 0x00
-#define PATTERN_COPY 0x40
-#define PATTERN_OVERWRITE 0x20
-#define PATTERN_COUNT_MASK 0x1f
-
-struct dmatest_info;
-
-struct dmatest_thread {
- struct list_head node;
- struct dmatest_info *info;
- struct task_struct *task;
- struct dma_chan *chan;
- u8 **srcs;
- u8 **dsts;
- enum dma_transaction_type type;
- bool done;
-};
-
-struct dmatest_chan {
- struct list_head node;
- struct dma_chan *chan;
- struct list_head threads;
-};
-
/**
* struct dmatest_params - test parameters.
* @buf_size: size of the memcpy test buffer
@@ -138,7 +95,7 @@ struct dmatest_params {
* @params: test parameters
* @lock: access protection to the fields of this structure
*/
-struct dmatest_info {
+static struct dmatest_info {
/* Test parameters */
struct dmatest_params params;
@@ -146,12 +103,58 @@ struct dmatest_info {
struct list_head channels;
unsigned int nr_channels;
struct mutex lock;
+ bool did_init;
+} test_info = {
+ .channels = LIST_HEAD_INIT(test_info.channels),
+ .lock = __MUTEX_INITIALIZER(test_info.lock),
+};
- /* debugfs related stuff */
- struct dentry *root;
+static int dmatest_run_set(const char *val, const struct kernel_param *kp);
+static int dmatest_run_get(char *val, const struct kernel_param *kp);
+static struct kernel_param_ops run_ops = {
+ .set = dmatest_run_set,
+ .get = dmatest_run_get,
};
+static bool dmatest_run;
+module_param_cb(run, &run_ops, &dmatest_run, S_IRUGO | S_IWUSR);
+MODULE_PARM_DESC(run, "Run the test (default: false)");
-static struct dmatest_info test_info;
+/* Maximum amount of mismatched bytes in buffer to print */
+#define MAX_ERROR_COUNT 32
+
+/*
+ * Initialization patterns. All bytes in the source buffer has bit 7
+ * set, all bytes in the destination buffer has bit 7 cleared.
+ *
+ * Bit 6 is set for all bytes which are to be copied by the DMA
+ * engine. Bit 5 is set for all bytes which are to be overwritten by
+ * the DMA engine.
+ *
+ * The remaining bits are the inverse of a counter which increments by
+ * one for each byte address.
+ */
+#define PATTERN_SRC 0x80
+#define PATTERN_DST 0x00
+#define PATTERN_COPY 0x40
+#define PATTERN_OVERWRITE 0x20
+#define PATTERN_COUNT_MASK 0x1f
+
+struct dmatest_thread {
+ struct list_head node;
+ struct dmatest_info *info;
+ struct task_struct *task;
+ struct dma_chan *chan;
+ u8 **srcs;
+ u8 **dsts;
+ enum dma_transaction_type type;
+ bool done;
+};
+
+struct dmatest_chan {
+ struct list_head node;
+ struct dma_chan *chan;
+ struct list_head threads;
+};
static bool dmatest_match_channel(struct dmatest_params *params,
struct dma_chan *chan)
@@ -731,13 +734,24 @@ static bool filter(struct dma_chan *chan, void *param)
return true;
}
-static int __run_threaded_test(struct dmatest_info *info)
+static int run_threaded_test(struct dmatest_info *info)
{
dma_cap_mask_t mask;
struct dma_chan *chan;
struct dmatest_params *params = &info->params;
int err = 0;
+ /* Copy test parameters */
+ params->buf_size = test_buf_size;
+ strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
+ strlcpy(params->device, strim(test_device), sizeof(params->device));
+ params->threads_per_chan = threads_per_chan;
+ params->max_channels = max_channels;
+ params->iterations = iterations;
+ params->xor_sources = xor_sources;
+ params->pq_sources = pq_sources;
+ params->timeout = timeout;
+
dma_cap_zero(mask);
dma_cap_set(DMA_MEMCPY, mask);
for (;;) {
@@ -757,19 +771,8 @@ static int __run_threaded_test(struct dmatest_info *info)
return err;
}
-#ifndef MODULE
-static int run_threaded_test(struct dmatest_info *info)
-{
- int ret;
-
- mutex_lock(&info->lock);
- ret = __run_threaded_test(info);
- mutex_unlock(&info->lock);
- return ret;
-}
-#endif
-static void __stop_threaded_test(struct dmatest_info *info)
+static void stop_threaded_test(struct dmatest_info *info)
{
struct dmatest_chan *dtc, *_dtc;
struct dma_chan *chan;
@@ -785,39 +788,22 @@ static void __stop_threaded_test(struct dmatest_info *info)
info->nr_channels = 0;
}
-static void stop_threaded_test(struct dmatest_info *info)
-{
- mutex_lock(&info->lock);
- __stop_threaded_test(info);
- mutex_unlock(&info->lock);
-}
-
-static int __restart_threaded_test(struct dmatest_info *info, bool run)
+static int restart_threaded_test(struct dmatest_info *info, bool run)
{
- struct dmatest_params *params = &info->params;
-
- /* Stop any running test first */
- __stop_threaded_test(info);
-
- if (run == false)
+ /* we might be called early to set run=, defer running until all
+ * parameters have been evaluated
+ */
+ if (!info->did_init)
return 0;
- /* Copy test parameters */
- params->buf_size = test_buf_size;
- strlcpy(params->channel, strim(test_channel), sizeof(params->channel));
- strlcpy(params->device, strim(test_device), sizeof(params->device));
- params->threads_per_chan = threads_per_chan;
- params->max_channels = max_channels;
- params->iterations = iterations;
- params->xor_sources = xor_sources;
- params->pq_sources = pq_sources;
- params->timeout = timeout;
+ /* Stop any running test first */
+ stop_threaded_test(info);
/* Run test with new parameters */
- return __run_threaded_test(info);
+ return run_threaded_test(info);
}
-static bool __is_threaded_test_run(struct dmatest_info *info)
+static bool is_threaded_test_run(struct dmatest_info *info)
{
struct dmatest_chan *dtc;
@@ -833,101 +819,61 @@ static bool __is_threaded_test_run(struct dmatest_info *info)
return false;
}
-static ssize_t dtf_read_run(struct file *file, char __user *user_buf,
- size_t count, loff_t *ppos)
+static int dmatest_run_get(char *val, const struct kernel_param *kp)
{
- struct dmatest_info *info = file->private_data;
- char buf[3];
+ struct dmatest_info *info = &test_info;
mutex_lock(&info->lock);
-
- if (__is_threaded_test_run(info)) {
- buf[0] = 'Y';
+ if (is_threaded_test_run(info)) {
+ dmatest_run = true;
} else {
- __stop_threaded_test(info);
- buf[0] = 'N';
+ stop_threaded_test(info);
+ dmatest_run = false;
}
-
mutex_unlock(&info->lock);
- buf[1] = '\n';
- buf[2] = 0x00;
- return simple_read_from_buffer(user_buf, count, ppos, buf, 2);
+
+ return param_get_bool(val, kp);
}
-static ssize_t dtf_write_run(struct file *file, const char __user *user_buf,
- size_t count, loff_t *ppos)
+static int dmatest_run_set(const char *val, const struct kernel_param *kp)
{
- struct dmatest_info *info = file->private_data;
- char buf[16];
- bool bv;
- int ret = 0;
-
- if (copy_from_user(buf, user_buf, min(count, (sizeof(buf) - 1))))
- return -EFAULT;
-
- if (strtobool(buf, &bv) == 0) {
- mutex_lock(&info->lock);
-
- if (__is_threaded_test_run(info))
- ret = -EBUSY;
- else
- ret = __restart_threaded_test(info, bv);
+ struct dmatest_info *info = &test_info;
+ int ret;
+ mutex_lock(&info->lock);
+ ret = param_set_bool(val, kp);
+ if (ret) {
mutex_unlock(&info->lock);
+ return ret;
}
- return ret ? ret : count;
-}
-
-static const struct file_operations dtf_run_fops = {
- .read = dtf_read_run,
- .write = dtf_write_run,
- .open = simple_open,
- .llseek = default_llseek,
-};
-
-static int dmatest_register_dbgfs(struct dmatest_info *info)
-{
- struct dentry *d;
-
- d = debugfs_create_dir("dmatest", NULL);
- if (IS_ERR(d))
- return PTR_ERR(d);
- if (!d)
- goto err_root;
+ if (is_threaded_test_run(info))
+ ret = -EBUSY;
+ else if (dmatest_run)
+ ret = restart_threaded_test(info, dmatest_run);
- info->root = d;
-
- /* Run or stop threaded test */
- debugfs_create_file("run", S_IWUSR | S_IRUGO, info->root, info,
- &dtf_run_fops);
-
- return 0;
+ mutex_unlock(&info->lock);
-err_root:
- pr_err("Failed to initialize debugfs\n");
- return -ENOMEM;
+ return ret;
}
static int __init dmatest_init(void)
{
struct dmatest_info *info = &test_info;
- int ret;
-
- memset(info, 0, sizeof(*info));
+ int ret = 0;
- mutex_init(&info->lock);
- INIT_LIST_HEAD(&info->channels);
+ if (dmatest_run) {
+ mutex_lock(&info->lock);
+ ret = run_threaded_test(info);
+ mutex_unlock(&info->lock);
+ }
- ret = dmatest_register_dbgfs(info);
- if (ret)
- return ret;
+ /* module parameters are stable, inittime tests are started,
+ * let userspace take over 'run' control
+ */
+ info->did_init = true;
-#ifdef MODULE
- return 0;
-#else
- return run_threaded_test(info);
-#endif
+ return ret;
}
/* when compiled-in wait for drivers to load first */
late_initcall(dmatest_init);
@@ -936,8 +882,9 @@ static void __exit dmatest_exit(void)
{
struct dmatest_info *info = &test_info;
- debugfs_remove_recursive(info->root);
+ mutex_lock(&info->lock);
stop_threaded_test(info);
+ mutex_unlock(&info->lock);
}
module_exit(dmatest_exit);
1/ move 'run' control to a module parameter so we can do: modprobe dmatest run=1. With this moved the rest of the debugfs boilerplate can go. 2/ Fix parameter initialization. Previously the test was being started without taking the parameters into account in the built-in case. Also killed off the '__' version of some routines. The new rule is just hold the lock when calling a *threaded_test() routine. Cc: Linus Walleij <linus.walleij@linaro.org> Cc: Andy Shevchenko <andriy.shevchenko@linux.intel.com> Signed-off-by: Dan Williams <dan.j.williams@intel.com> --- Documentation/dmatest.txt | 14 +- drivers/dma/dmatest.c | 265 ++++++++++++++++++--------------------------- 2 files changed, 112 insertions(+), 167 deletions(-) -- To unsubscribe from this list: send the line "unsubscribe dmaengine" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html