When looking at the pwrite/pread/wc performance, it is useful to judge
that against the performance of an ordinary CPU mmap.
Signed-off-by: Chris Wilson <chris at chris-wilson.co.uk>
---
lib/drmtest.c | 15 ++++++++++-
lib/drmtest.h | 6 ++++-
tests/gem_gtt_speed.c | 72 +++++++++++++++++++++++++++++++++++++++++++------
tests/gem_mmap.c | 22 +++++++--------
4 files changed, 94 insertions(+), 21 deletions(-)
diff --git a/lib/drmtest.c b/lib/drmtest.c
index f9f10e1..cdf46aa 100644
--- a/lib/drmtest.c
+++ b/lib/drmtest.c
@@ -311,7 +311,7 @@ uint32_t gem_create(int fd, int size)
return create.handle;
}
-void *gem_mmap(int fd, uint32_t handle, int size, int prot)
+void *gem_mmap__gtt(int fd, uint32_t handle, int size, int prot)
{
struct drm_i915_gem_mmap_gtt mmap_arg;
void *ptr;
@@ -327,6 +327,19 @@ void *gem_mmap(int fd, uint32_t handle, int size, int prot)
return ptr;
}
+void *gem_mmap__cpu(int fd, uint32_t handle, int size, int prot)
+{
+ struct drm_i915_gem_mmap mmap_arg;
+
+ mmap_arg.handle = handle;
+ mmap_arg.offset = 0;
+ mmap_arg.size = size;
+ if (drmIoctl(fd, DRM_IOCTL_I915_GEM_MMAP, &mmap_arg))
+ return NULL;
+
+ return (void *)(uintptr_t)mmap_arg.addr_ptr;
+}
+
uint64_t gem_aperture_size(int fd)
{
struct drm_i915_gem_get_aperture aperture;
diff --git a/lib/drmtest.h b/lib/drmtest.h
index 9f27e2c..4021104 100644
--- a/lib/drmtest.h
+++ b/lib/drmtest.h
@@ -52,7 +52,11 @@ void gem_set_domain(int fd, uint32_t handle,
uint32_t read_domains, uint32_t write_domain);
void gem_sync(int fd, uint32_t handle);
uint32_t gem_create(int fd, int size);
-void *gem_mmap(int fd, uint32_t handle, int size, int prot);
+
+void *gem_mmap__gtt(int fd, uint32_t handle, int size, int prot);
+void *gem_mmap__cpu(int fd, uint32_t handle, int size, int prot);
+#define gem_mmap gem_mmap__gtt
+
uint64_t gem_aperture_size(int fd);
uint64_t gem_mappable_aperture_size(void);
int gem_madvise(int fd, uint32_t handle, int state);
diff --git a/tests/gem_gtt_speed.c b/tests/gem_gtt_speed.c
index 69cd1ff..73a3c6d 100644
--- a/tests/gem_gtt_speed.c
+++ b/tests/gem_gtt_speed.c
@@ -83,6 +83,58 @@ int main(int argc, char **argv)
}
if (tiling == I915_TILING_NONE) {
+ gem_set_domain(fd, handle,
+ I915_GEM_DOMAIN_CPU,
+ I915_GEM_DOMAIN_CPU);
+
+ {
+ uint32_t *base = gem_mmap__cpu(fd, handle, size, PROT_READ | PROT_WRITE);
+ volatile uint32_t *ptr = base;
+ int x = 0;
+
+ for (i = 0; i < size/sizeof(*ptr); i++)
+ x += ptr[i];
+
+ /* force overtly clever gcc to actually compute x */
+ ptr[0] = x;
+
+ munmap(base, size);
+
+ /* mmap read */
+ gettimeofday(&start, NULL);
+ for (loop = 0; loop < 1000; loop++) {
+ base = gem_mmap__cpu(fd, handle, size, PROT_READ | PROT_WRITE);
+ ptr = base;
+ x = 0;
+
+ for (i = 0; i < size/sizeof(*ptr); i++)
+ x += ptr[i];
+
+ /* force overtly clever gcc to actually compute x */
+ ptr[0] = x;
+
+ munmap(base, size);
+ }
+ gettimeofday(&end, NULL);
+ printf("Time to read %dk through a CPU map: %7.3f?s\n",
+ size/1024, elapsed(&start, &end, loop));
+
+ /* mmap write */
+ gettimeofday(&start, NULL);
+ for (loop = 0; loop < 1000; loop++) {
+ base = gem_mmap__cpu(fd, handle, size, PROT_READ | PROT_WRITE);
+ ptr = base;
+
+ for (i = 0; i < size/sizeof(*ptr); i++)
+ ptr[i] = i;
+
+ munmap(base, size);
+ }
+ gettimeofday(&end, NULL);
+ printf("Time to write %dk through a CPU map: %7.3f?s\n",
+ size/1024, elapsed(&start, &end, loop));
+ }
+
/* CPU pwrite */
gettimeofday(&start, NULL);
for (loop = 0; loop < 1000; loop++)
@@ -102,7 +154,8 @@ int main(int argc, char **argv)
/* prefault into gtt */
{
- uint32_t *ptr = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ uint32_t *base = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ volatile uint32_t *ptr = base;
int x = 0;
for (i = 0; i < size/sizeof(*ptr); i++)
@@ -111,12 +164,13 @@ int main(int argc, char **argv)
/* force overtly clever gcc to actually compute x */
ptr[0] = x;
- munmap(ptr, size);
+ munmap(base, size);
}
/* mmap read */
gettimeofday(&start, NULL);
for (loop = 0; loop < 1000; loop++) {
- uint32_t *ptr = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ uint32_t *base = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ volatile uint32_t *ptr = base;
int x = 0;
for (i = 0; i < size/sizeof(*ptr); i++)
@@ -125,7 +179,7 @@ int main(int argc, char **argv)
/* force overtly clever gcc to actually compute x */
ptr[0] = x;
- munmap(ptr, size);
+ munmap(base, size);
}
gettimeofday(&end, NULL);
printf("Time to read %dk through a GTT map: %7.3f?s\n",
@@ -134,12 +188,13 @@ int main(int argc, char **argv)
/* mmap write */
gettimeofday(&start, NULL);
for (loop = 0; loop < 1000; loop++) {
- uint32_t *ptr = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ uint32_t *base = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ volatile uint32_t *ptr = base;
for (i = 0; i < size/sizeof(*ptr); i++)
ptr[i] = i;
- munmap(ptr, size);
+ munmap(base, size);
}
gettimeofday(&end, NULL);
printf("Time to write %dk through a GTT map: %7.3f?s\n",
@@ -148,7 +203,8 @@ int main(int argc, char **argv)
/* mmap read */
gettimeofday(&start, NULL);
for (loop = 0; loop < 1000; loop++) {
- uint32_t *ptr = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ uint32_t *base = gem_mmap(fd, handle, size, PROT_READ | PROT_WRITE);
+ volatile uint32_t *ptr = base;
int x = 0;
for (i = 0; i < size/sizeof(*ptr); i++)
@@ -157,7 +213,7 @@ int main(int argc, char **argv)
/* force overtly clever gcc to actually compute x */
ptr[0] = x;
- munmap(ptr, size);
+ munmap(base, size);
}
gettimeofday(&end, NULL);
printf("Time to read %dk (again) through a GTT map: %7.3f?s\n",
diff --git a/tests/gem_mmap.c b/tests/gem_mmap.c
index 6ba6e3b..f9369f4 100644
--- a/tests/gem_mmap.c
+++ b/tests/gem_mmap.c
@@ -45,7 +45,7 @@
int main(int argc, char **argv)
{
int fd;
- struct drm_i915_gem_mmap gem_mmap;
+ struct drm_i915_gem_mmap arg;
uint8_t expected[OBJECT_SIZE];
uint8_t buf[OBJECT_SIZE];
uint8_t *addr;
@@ -54,23 +54,23 @@ int main(int argc, char **argv)
fd = drm_open_any();
- memset(&gem_mmap, 0, sizeof(gem_mmap));
- gem_mmap.handle = 0x10101010;
- gem_mmap.offset = 0;
- gem_mmap.size = 4096;
+ memset(&arg, 0, sizeof(arg));
+ arg.handle = 0x10101010;
+ arg.offset = 0;
+ arg.size = 4096;
printf("Testing mmaping of bad object.\n");
- ret = ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &gem_mmap);
+ ret = ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &arg);
assert(ret == -1 && errno == ENOENT);
handle = gem_create(fd, OBJECT_SIZE);
printf("Testing mmaping of newly created object.\n");
- gem_mmap.handle = handle;
- gem_mmap.offset = 0;
- gem_mmap.size = OBJECT_SIZE;
- ret = ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &gem_mmap);
+ arg.handle = handle;
+ arg.offset = 0;
+ arg.size = OBJECT_SIZE;
+ ret = ioctl(fd, DRM_IOCTL_I915_GEM_MMAP, &arg);
assert(ret == 0);
- addr = (uint8_t *)(uintptr_t)gem_mmap.addr_ptr;
+ addr = (uint8_t *)(uintptr_t)arg.addr_ptr;
printf("Testing contents of newly created object.\n");
memset(expected, 0, sizeof(expected));
--
1.7.10
