In this patch map_benchmark abstract in four interface: prepare, unprepare,
do_map, do_unmap. When there's a new mode to add, need four steps:
1) Add the mode in map_benchmark.h
2) Defines the mode param, like struct dma_xxx_map_param, and this object
will be return in prepare and as input parameter in other ops;
3) Defines the ops functions:prepare, unprepare, do_map, do_unmap.
4) Add the new mode in dma_map_benchmark_ops.
Signed-off-by: Qinxin Xia <xiaqinxin@huawei.com>
---
include/linux/map_benchmark.h | 8 ++-
kernel/dma/map_benchmark.c | 120 +++++++++++++++++++++++++++-------
2 files changed, 104 insertions(+), 24 deletions(-)
diff --git a/include/linux/map_benchmark.h b/include/linux/map_benchmark.h
index 2ac2fe52f248..5294dfd1870f 100644
--- a/include/linux/map_benchmark.h
+++ b/include/linux/map_benchmark.h
@@ -15,6 +15,11 @@
#define DMA_MAP_TO_DEVICE 1
#define DMA_MAP_FROM_DEVICE 2
+enum {
+ DMA_MAP_SINGLE_MODE,
+ DMA_MAP_MODE_MAX
+};
+
struct map_benchmark {
__u64 avg_map_100ns; /* average map latency in 100ns */
__u64 map_stddev; /* standard deviation of map latency */
@@ -27,6 +32,7 @@ struct map_benchmark {
__u32 dma_dir; /* DMA data direction */
__u32 dma_trans_ns; /* time for DMA transmission in ns */
__u32 granule; /* how many PAGE_SIZE will do map/unmap once a time */
- __u8 expansion[76]; /* For future use */
+ __u8 map_mode; /* the mode of dma map */
+ __u8 expansion[75]; /* For future use */
};
#endif /* _KERNEL_DMA_BENCHMARK_H */
diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
index cc19a3efea89..f04973eba1d8 100644
--- a/kernel/dma/map_benchmark.c
+++ b/kernel/dma/map_benchmark.c
@@ -5,6 +5,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+#include <linux/cleanup.h>
#include <linux/debugfs.h>
#include <linux/delay.h>
#include <linux/device.h>
@@ -31,17 +32,97 @@ struct map_benchmark_data {
atomic64_t loops;
};
+struct map_benchmark_ops {
+ void *(*prepare)(struct map_benchmark_data *map);
+ void (*unprepare)(void *arg);
+ int (*do_map)(void *arg);
+ void (*do_unmap)(void *arg);
+};
+
+struct dma_single_map_param {
+ struct device *dev;
+ dma_addr_t addr;
+ void *xbuf;
+ u32 npages;
+ u32 dma_dir;
+};
+
+static void *dma_single_map_benchmark_prepare(struct map_benchmark_data *map)
+{
+ struct dma_single_map_param *mparam __free(kfree) = kzalloc(sizeof(*mparam),
+ GFP_KERNEL);
+ if (!mparam)
+ return NULL;
+
+ mparam->npages = map->bparam.granule;
+ mparam->dma_dir = map->bparam.dma_dir;
+ mparam->dev = map->dev;
+ mparam->xbuf = alloc_pages_exact(mparam->npages * PAGE_SIZE, GFP_KERNEL);
+ if (!mparam->xbuf)
+ return NULL;
+
+ /*
+ * for a non-coherent device, if we don't stain them in the
+ * cache, this will give an underestimate of the real-world
+ * overhead of BIDIRECTIONAL or TO_DEVICE mappings;
+ * 66 means evertything goes well! 66 is lucky.
+ */
+ if (mparam->dma_dir != DMA_FROM_DEVICE)
+ memset(mparam->xbuf, 0x66, mparam->npages * PAGE_SIZE);
+
+ return_ptr(mparam);
+}
+
+static void dma_single_map_benchmark_unprepare(void *arg)
+{
+ struct dma_single_map_param *mparam = arg;
+
+ free_pages_exact(mparam->xbuf, mparam->npages * PAGE_SIZE);
+ kfree(mparam);
+}
+
+static int dma_single_map_benchmark_do_map(void *arg)
+{
+ struct dma_single_map_param *mparam = arg;
+
+ mparam->addr = dma_map_single(mparam->dev, mparam->xbuf,
+ mparam->npages * PAGE_SIZE, mparam->dma_dir);
+ if (unlikely(dma_mapping_error(mparam->dev, mparam->addr))) {
+ pr_err("dma_map_single failed on %s\n", dev_name(mparam->dev));
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
+static void dma_single_map_benchmark_do_unmap(void *arg)
+{
+ struct dma_single_map_param *mparam = arg;
+
+ dma_unmap_single(mparam->dev, mparam->addr,
+ mparam->npages * PAGE_SIZE, mparam->dma_dir);
+}
+
+static struct map_benchmark_ops dma_single_map_benchmark_ops = {
+ .prepare = dma_single_map_benchmark_prepare,
+ .unprepare = dma_single_map_benchmark_unprepare,
+ .do_map = dma_single_map_benchmark_do_map,
+ .do_unmap = dma_single_map_benchmark_do_unmap,
+};
+
+static struct map_benchmark_ops *dma_map_benchmark_ops[DMA_MAP_MODE_MAX] = {
+ [DMA_MAP_SINGLE_MODE] = &dma_single_map_benchmark_ops,
+};
+
static int map_benchmark_thread(void *data)
{
- void *buf;
- dma_addr_t dma_addr;
struct map_benchmark_data *map = data;
- int npages = map->bparam.granule;
- u64 size = npages * PAGE_SIZE;
+ __u8 map_mode = map->bparam.map_mode;
int ret = 0;
- buf = alloc_pages_exact(size, GFP_KERNEL);
- if (!buf)
+ void *arg = dma_map_benchmark_ops[map_mode]->prepare(map);
+
+ if (!arg)
return -ENOMEM;
while (!kthread_should_stop()) {
@@ -49,23 +130,10 @@ static int map_benchmark_thread(void *data)
ktime_t map_stime, map_etime, unmap_stime, unmap_etime;
ktime_t map_delta, unmap_delta;
- /*
- * for a non-coherent device, if we don't stain them in the
- * cache, this will give an underestimate of the real-world
- * overhead of BIDIRECTIONAL or TO_DEVICE mappings;
- * 66 means evertything goes well! 66 is lucky.
- */
- if (map->dir != DMA_FROM_DEVICE)
- memset(buf, 0x66, size);
-
map_stime = ktime_get();
- dma_addr = dma_map_single(map->dev, buf, size, map->dir);
- if (unlikely(dma_mapping_error(map->dev, dma_addr))) {
- pr_err("dma_map_single failed on %s\n",
- dev_name(map->dev));
- ret = -ENOMEM;
+ ret = dma_map_benchmark_ops[map_mode]->do_map(arg);
+ if (ret)
goto out;
- }
map_etime = ktime_get();
map_delta = ktime_sub(map_etime, map_stime);
@@ -73,7 +141,8 @@ static int map_benchmark_thread(void *data)
ndelay(map->bparam.dma_trans_ns);
unmap_stime = ktime_get();
- dma_unmap_single(map->dev, dma_addr, size, map->dir);
+ dma_map_benchmark_ops[map_mode]->do_unmap(arg);
+
unmap_etime = ktime_get();
unmap_delta = ktime_sub(unmap_etime, unmap_stime);
@@ -108,7 +177,7 @@ static int map_benchmark_thread(void *data)
}
out:
- free_pages_exact(buf, size);
+ dma_map_benchmark_ops[map_mode]->unprepare(arg);
return ret;
}
@@ -209,6 +278,11 @@ static long map_benchmark_ioctl(struct file *file, unsigned int cmd,
switch (cmd) {
case DMA_MAP_BENCHMARK:
+ if (map->bparam.map_mode >= DMA_MAP_MODE_MAX) {
+ pr_err("invalid map mode\n");
+ return -EINVAL;
+ }
+
if (map->bparam.threads == 0 ||
map->bparam.threads > DMA_MAP_MAX_THREADS) {
pr_err("invalid thread number\n");
--
2.33.0On Tue, May 6, 2025 at 3:01 PM Qinxin Xia <xiaqinxin@huawei.com> wrote:
>
> In this patch map_benchmark abstract in four interface: prepare, unprepare,
> do_map, do_unmap. When there's a new mode to add, need four steps:
> 1) Add the mode in map_benchmark.h
> 2) Defines the mode param, like struct dma_xxx_map_param, and this object
> will be return in prepare and as input parameter in other ops;
> 3) Defines the ops functions:prepare, unprepare, do_map, do_unmap.
> 4) Add the new mode in dma_map_benchmark_ops.
There are too many irrelevant details.
We're more interested in the reasoning behind this change than just the change
itself. There should be some explanation of the purpose.
>
> Signed-off-by: Qinxin Xia <xiaqinxin@huawei.com>
> ---
> include/linux/map_benchmark.h | 8 ++-
> kernel/dma/map_benchmark.c | 120 +++++++++++++++++++++++++++-------
> 2 files changed, 104 insertions(+), 24 deletions(-)
>
> diff --git a/include/linux/map_benchmark.h b/include/linux/map_benchmark.h
> index 2ac2fe52f248..5294dfd1870f 100644
> --- a/include/linux/map_benchmark.h
> +++ b/include/linux/map_benchmark.h
> @@ -15,6 +15,11 @@
> #define DMA_MAP_TO_DEVICE 1
> #define DMA_MAP_FROM_DEVICE 2
>
> +enum {
> + DMA_MAP_SINGLE_MODE,
> + DMA_MAP_MODE_MAX
> +};
> +
> struct map_benchmark {
> __u64 avg_map_100ns; /* average map latency in 100ns */
> __u64 map_stddev; /* standard deviation of map latency */
> @@ -27,6 +32,7 @@ struct map_benchmark {
> __u32 dma_dir; /* DMA data direction */
> __u32 dma_trans_ns; /* time for DMA transmission in ns */
> __u32 granule; /* how many PAGE_SIZE will do map/unmap once a time */
> - __u8 expansion[76]; /* For future use */
> + __u8 map_mode; /* the mode of dma map */
> + __u8 expansion[75]; /* For future use */
> };
> #endif /* _KERNEL_DMA_BENCHMARK_H */
> diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
> index cc19a3efea89..f04973eba1d8 100644
> --- a/kernel/dma/map_benchmark.c
> +++ b/kernel/dma/map_benchmark.c
> @@ -5,6 +5,7 @@
>
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> +#include <linux/cleanup.h>
> #include <linux/debugfs.h>
> #include <linux/delay.h>
> #include <linux/device.h>
> @@ -31,17 +32,97 @@ struct map_benchmark_data {
> atomic64_t loops;
> };
>
> +struct map_benchmark_ops {
> + void *(*prepare)(struct map_benchmark_data *map);
> + void (*unprepare)(void *arg);
> + int (*do_map)(void *arg);
> + void (*do_unmap)(void *arg);
> +};
> +
> +struct dma_single_map_param {
> + struct device *dev;
> + dma_addr_t addr;
> + void *xbuf;
> + u32 npages;
> + u32 dma_dir;
> +};
> +
> +static void *dma_single_map_benchmark_prepare(struct map_benchmark_data *map)
> +{
> + struct dma_single_map_param *mparam __free(kfree) = kzalloc(sizeof(*mparam),
> + GFP_KERNEL);
> + if (!mparam)
> + return NULL;
> +
> + mparam->npages = map->bparam.granule;
> + mparam->dma_dir = map->bparam.dma_dir;
> + mparam->dev = map->dev;
> + mparam->xbuf = alloc_pages_exact(mparam->npages * PAGE_SIZE, GFP_KERNEL);
> + if (!mparam->xbuf)
> + return NULL;
> +
> + /*
> + * for a non-coherent device, if we don't stain them in the
> + * cache, this will give an underestimate of the real-world
> + * overhead of BIDIRECTIONAL or TO_DEVICE mappings;
> + * 66 means evertything goes well! 66 is lucky.
> + */
> + if (mparam->dma_dir != DMA_FROM_DEVICE)
> + memset(mparam->xbuf, 0x66, mparam->npages * PAGE_SIZE);
> +
> + return_ptr(mparam);
> +}
> +
> +static void dma_single_map_benchmark_unprepare(void *arg)
> +{
> + struct dma_single_map_param *mparam = arg;
> +
> + free_pages_exact(mparam->xbuf, mparam->npages * PAGE_SIZE);
> + kfree(mparam);
> +}
> +
> +static int dma_single_map_benchmark_do_map(void *arg)
> +{
> + struct dma_single_map_param *mparam = arg;
> +
> + mparam->addr = dma_map_single(mparam->dev, mparam->xbuf,
> + mparam->npages * PAGE_SIZE, mparam->dma_dir);
> + if (unlikely(dma_mapping_error(mparam->dev, mparam->addr))) {
> + pr_err("dma_map_single failed on %s\n", dev_name(mparam->dev));
> + return -ENOMEM;
> + }
> +
> + return 0;
> +}
> +
> +static void dma_single_map_benchmark_do_unmap(void *arg)
> +{
> + struct dma_single_map_param *mparam = arg;
> +
> + dma_unmap_single(mparam->dev, mparam->addr,
> + mparam->npages * PAGE_SIZE, mparam->dma_dir);
> +}
> +
> +static struct map_benchmark_ops dma_single_map_benchmark_ops = {
> + .prepare = dma_single_map_benchmark_prepare,
> + .unprepare = dma_single_map_benchmark_unprepare,
> + .do_map = dma_single_map_benchmark_do_map,
> + .do_unmap = dma_single_map_benchmark_do_unmap,
> +};
> +
> +static struct map_benchmark_ops *dma_map_benchmark_ops[DMA_MAP_MODE_MAX] = {
> + [DMA_MAP_SINGLE_MODE] = &dma_single_map_benchmark_ops,
> +};
> +
> static int map_benchmark_thread(void *data)
> {
> - void *buf;
> - dma_addr_t dma_addr;
> struct map_benchmark_data *map = data;
> - int npages = map->bparam.granule;
> - u64 size = npages * PAGE_SIZE;
> + __u8 map_mode = map->bparam.map_mode;
> int ret = 0;
>
> - buf = alloc_pages_exact(size, GFP_KERNEL);
> - if (!buf)
> + void *arg = dma_map_benchmark_ops[map_mode]->prepare(map);
It's a bit awkward. Let's try something like this instead:
struct map_benchmark_ops *mb_ops = &dma_map_benchmark_ops[map_mode];
then
mb_ops->prepare()/map/unmap/unprepare etc.
And can you find a better name than "arg" which is meaningless, mparam?
> +
> + if (!arg)
> return -ENOMEM;
>
> while (!kthread_should_stop()) {
> @@ -49,23 +130,10 @@ static int map_benchmark_thread(void *data)
> ktime_t map_stime, map_etime, unmap_stime, unmap_etime;
> ktime_t map_delta, unmap_delta;
>
> - /*
> - * for a non-coherent device, if we don't stain them in the
> - * cache, this will give an underestimate of the real-world
> - * overhead of BIDIRECTIONAL or TO_DEVICE mappings;
> - * 66 means evertything goes well! 66 is lucky.
> - */
> - if (map->dir != DMA_FROM_DEVICE)
> - memset(buf, 0x66, size);
> -
> map_stime = ktime_get();
> - dma_addr = dma_map_single(map->dev, buf, size, map->dir);
> - if (unlikely(dma_mapping_error(map->dev, dma_addr))) {
> - pr_err("dma_map_single failed on %s\n",
> - dev_name(map->dev));
> - ret = -ENOMEM;
> + ret = dma_map_benchmark_ops[map_mode]->do_map(arg);
> + if (ret)
> goto out;
> - }
> map_etime = ktime_get();
> map_delta = ktime_sub(map_etime, map_stime);
>
> @@ -73,7 +141,8 @@ static int map_benchmark_thread(void *data)
> ndelay(map->bparam.dma_trans_ns);
>
> unmap_stime = ktime_get();
> - dma_unmap_single(map->dev, dma_addr, size, map->dir);
> + dma_map_benchmark_ops[map_mode]->do_unmap(arg);
> +
> unmap_etime = ktime_get();
> unmap_delta = ktime_sub(unmap_etime, unmap_stime);
>
> @@ -108,7 +177,7 @@ static int map_benchmark_thread(void *data)
> }
>
> out:
> - free_pages_exact(buf, size);
> + dma_map_benchmark_ops[map_mode]->unprepare(arg);
> return ret;
> }
>
> @@ -209,6 +278,11 @@ static long map_benchmark_ioctl(struct file *file, unsigned int cmd,
>
> switch (cmd) {
> case DMA_MAP_BENCHMARK:
> + if (map->bparam.map_mode >= DMA_MAP_MODE_MAX) {
> + pr_err("invalid map mode\n");
> + return -EINVAL;
> + }
> +
> if (map->bparam.threads == 0 ||
> map->bparam.threads > DMA_MAP_MAX_THREADS) {
> pr_err("invalid thread number\n");
> --
> 2.33.0
>
Thanks
Barry
在 2025/5/7 10:30, Barry Song 写道:
> On Tue, May 6, 2025 at 3:01 PM Qinxin Xia <xiaqinxin@huawei.com> wrote:
>> In this patch map_benchmark abstract in four interface: prepare, unprepare,
>> do_map, do_unmap. When there's a new mode to add, need four steps:
>> 1) Add the mode in map_benchmark.h
>> 2) Defines the mode param, like struct dma_xxx_map_param, and this object
>> will be return in prepare and as input parameter in other ops;
>> 3) Defines the ops functions:prepare, unprepare, do_map, do_unmap.
>> 4) Add the new mode in dma_map_benchmark_ops.
> There are too many irrelevant details.
>
> We're more interested in the reasoning behind this change than just the change
> itself. There should be some explanation of the purpose.
Okay, I'm going to add some purposeful commit information.
>> Signed-off-by: Qinxin Xia <xiaqinxin@huawei.com>
>> ---
>> include/linux/map_benchmark.h | 8 ++-
>> kernel/dma/map_benchmark.c | 120 +++++++++++++++++++++++++++-------
>> 2 files changed, 104 insertions(+), 24 deletions(-)
>>
>> diff --git a/include/linux/map_benchmark.h b/include/linux/map_benchmark.h
>> index 2ac2fe52f248..5294dfd1870f 100644
>> --- a/include/linux/map_benchmark.h
>> +++ b/include/linux/map_benchmark.h
>> @@ -15,6 +15,11 @@
>> #define DMA_MAP_TO_DEVICE 1
>> #define DMA_MAP_FROM_DEVICE 2
>>
>> +enum {
>> + DMA_MAP_SINGLE_MODE,
>> + DMA_MAP_MODE_MAX
>> +};
>> +
>> struct map_benchmark {
>> __u64 avg_map_100ns; /* average map latency in 100ns */
>> __u64 map_stddev; /* standard deviation of map latency */
>> @@ -27,6 +32,7 @@ struct map_benchmark {
>> __u32 dma_dir; /* DMA data direction */
>> __u32 dma_trans_ns; /* time for DMA transmission in ns */
>> __u32 granule; /* how many PAGE_SIZE will do map/unmap once a time */
>> - __u8 expansion[76]; /* For future use */
>> + __u8 map_mode; /* the mode of dma map */
>> + __u8 expansion[75]; /* For future use */
>> };
>> #endif /* _KERNEL_DMA_BENCHMARK_H */
>> diff --git a/kernel/dma/map_benchmark.c b/kernel/dma/map_benchmark.c
>> index cc19a3efea89..f04973eba1d8 100644
>> --- a/kernel/dma/map_benchmark.c
>> +++ b/kernel/dma/map_benchmark.c
>> @@ -5,6 +5,7 @@
>>
>> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>>
>> +#include <linux/cleanup.h>
>> #include <linux/debugfs.h>
>> #include <linux/delay.h>
>> #include <linux/device.h>
>> @@ -31,17 +32,97 @@ struct map_benchmark_data {
>> atomic64_t loops;
>> };
>>
>> +struct map_benchmark_ops {
>> + void *(*prepare)(struct map_benchmark_data *map);
>> + void (*unprepare)(void *arg);
>> + int (*do_map)(void *arg);
>> + void (*do_unmap)(void *arg);
>> +};
>> +
>> +struct dma_single_map_param {
>> + struct device *dev;
>> + dma_addr_t addr;
>> + void *xbuf;
>> + u32 npages;
>> + u32 dma_dir;
>> +};
>> +
>> +static void *dma_single_map_benchmark_prepare(struct map_benchmark_data *map)
>> +{
>> + struct dma_single_map_param *mparam __free(kfree) = kzalloc(sizeof(*mparam),
>> + GFP_KERNEL);
>> + if (!mparam)
>> + return NULL;
>> +
>> + mparam->npages = map->bparam.granule;
>> + mparam->dma_dir = map->bparam.dma_dir;
>> + mparam->dev = map->dev;
>> + mparam->xbuf = alloc_pages_exact(mparam->npages * PAGE_SIZE, GFP_KERNEL);
>> + if (!mparam->xbuf)
>> + return NULL;
>> +
>> + /*
>> + * for a non-coherent device, if we don't stain them in the
>> + * cache, this will give an underestimate of the real-world
>> + * overhead of BIDIRECTIONAL or TO_DEVICE mappings;
>> + * 66 means evertything goes well! 66 is lucky.
>> + */
>> + if (mparam->dma_dir != DMA_FROM_DEVICE)
>> + memset(mparam->xbuf, 0x66, mparam->npages * PAGE_SIZE);
>> +
>> + return_ptr(mparam);
>> +}
>> +
>> +static void dma_single_map_benchmark_unprepare(void *arg)
>> +{
>> + struct dma_single_map_param *mparam = arg;
>> +
>> + free_pages_exact(mparam->xbuf, mparam->npages * PAGE_SIZE);
>> + kfree(mparam);
>> +}
>> +
>> +static int dma_single_map_benchmark_do_map(void *arg)
>> +{
>> + struct dma_single_map_param *mparam = arg;
>> +
>> + mparam->addr = dma_map_single(mparam->dev, mparam->xbuf,
>> + mparam->npages * PAGE_SIZE, mparam->dma_dir);
>> + if (unlikely(dma_mapping_error(mparam->dev, mparam->addr))) {
>> + pr_err("dma_map_single failed on %s\n", dev_name(mparam->dev));
>> + return -ENOMEM;
>> + }
>> +
>> + return 0;
>> +}
>> +
>> +static void dma_single_map_benchmark_do_unmap(void *arg)
>> +{
>> + struct dma_single_map_param *mparam = arg;
>> +
>> + dma_unmap_single(mparam->dev, mparam->addr,
>> + mparam->npages * PAGE_SIZE, mparam->dma_dir);
>> +}
>> +
>> +static struct map_benchmark_ops dma_single_map_benchmark_ops = {
>> + .prepare = dma_single_map_benchmark_prepare,
>> + .unprepare = dma_single_map_benchmark_unprepare,
>> + .do_map = dma_single_map_benchmark_do_map,
>> + .do_unmap = dma_single_map_benchmark_do_unmap,
>> +};
>> +
>> +static struct map_benchmark_ops *dma_map_benchmark_ops[DMA_MAP_MODE_MAX] = {
>> + [DMA_MAP_SINGLE_MODE] = &dma_single_map_benchmark_ops,
>> +};
>> +
>> static int map_benchmark_thread(void *data)
>> {
>> - void *buf;
>> - dma_addr_t dma_addr;
>> struct map_benchmark_data *map = data;
>> - int npages = map->bparam.granule;
>> - u64 size = npages * PAGE_SIZE;
>> + __u8 map_mode = map->bparam.map_mode;
>> int ret = 0;
>>
>> - buf = alloc_pages_exact(size, GFP_KERNEL);
>> - if (!buf)
>> + void *arg = dma_map_benchmark_ops[map_mode]->prepare(map);
> It's a bit awkward. Let's try something like this instead:
>
> struct map_benchmark_ops *mb_ops = &dma_map_benchmark_ops[map_mode];
>
> then
> mb_ops->prepare()/map/unmap/unprepare etc.
>
> And can you find a better name than "arg" which is meaningless, mparam?
OK, I'll change it in the next version according to your suggestion.
Thanks!
>> +
>> + if (!arg)
>> return -ENOMEM;
>>
>> while (!kthread_should_stop()) {
>> @@ -49,23 +130,10 @@ static int map_benchmark_thread(void *data)
>> ktime_t map_stime, map_etime, unmap_stime, unmap_etime;
>> ktime_t map_delta, unmap_delta;
>>
>> - /*
>> - * for a non-coherent device, if we don't stain them in the
>> - * cache, this will give an underestimate of the real-world
>> - * overhead of BIDIRECTIONAL or TO_DEVICE mappings;
>> - * 66 means evertything goes well! 66 is lucky.
>> - */
>> - if (map->dir != DMA_FROM_DEVICE)
>> - memset(buf, 0x66, size);
>> -
>> map_stime = ktime_get();
>> - dma_addr = dma_map_single(map->dev, buf, size, map->dir);
>> - if (unlikely(dma_mapping_error(map->dev, dma_addr))) {
>> - pr_err("dma_map_single failed on %s\n",
>> - dev_name(map->dev));
>> - ret = -ENOMEM;
>> + ret = dma_map_benchmark_ops[map_mode]->do_map(arg);
>> + if (ret)
>> goto out;
>> - }
>> map_etime = ktime_get();
>> map_delta = ktime_sub(map_etime, map_stime);
>>
>> @@ -73,7 +141,8 @@ static int map_benchmark_thread(void *data)
>> ndelay(map->bparam.dma_trans_ns);
>>
>> unmap_stime = ktime_get();
>> - dma_unmap_single(map->dev, dma_addr, size, map->dir);
>> + dma_map_benchmark_ops[map_mode]->do_unmap(arg);
>> +
>> unmap_etime = ktime_get();
>> unmap_delta = ktime_sub(unmap_etime, unmap_stime);
>>
>> @@ -108,7 +177,7 @@ static int map_benchmark_thread(void *data)
>> }
>>
>> out:
>> - free_pages_exact(buf, size);
>> + dma_map_benchmark_ops[map_mode]->unprepare(arg);
>> return ret;
>> }
>>
>> @@ -209,6 +278,11 @@ static long map_benchmark_ioctl(struct file *file, unsigned int cmd,
>>
>> switch (cmd) {
>> case DMA_MAP_BENCHMARK:
>> + if (map->bparam.map_mode >= DMA_MAP_MODE_MAX) {
>> + pr_err("invalid map mode\n");
>> + return -EINVAL;
>> + }
>> +
>> if (map->bparam.threads == 0 ||
>> map->bparam.threads > DMA_MAP_MAX_THREADS) {
>> pr_err("invalid thread number\n");
>> --
>> 2.33.0
>>
> Thanks
> Barry
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