| Message ID | 539f9b55a8269d3eb20d7d211f701d1a301d5b9d.1560374714.git.rodrigosiqueiramelo@gmail.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | igt: Add support for testing writeback connectors | expand |
Mostly LGTM, here are a few nits. On Wed, 2019-06-12 at 23:17 -0300, Brian Starkey wrote: > To use writeback buffers as a CRC source, we need to be able to hash > them. Implement a simple FVA-1a hashing routine for this purpose. > > Doing a bytewise hash on the framebuffer directly can be very slow if > the memory is noncached. By making a copy of each line in the FB first > (which can take advantage of word-access speedup), we can do the hash > on a cached copy, which is much faster (10x speedup on my platform). > > v6: use igt_memcpy_from_wc() instead of plain memcpy, as suggested by > Chris Wilson > > Signed-off-by: Brian Starkey <brian.starkey@arm.com> > [rebased and updated to the most recent API] > Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> > --- > lib/igt_fb.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > lib/igt_fb.h | 3 +++ > 2 files changed, 69 insertions(+) > > diff --git a/lib/igt_fb.c b/lib/igt_fb.c > index 9d4f905e..d07dae39 100644 > --- a/lib/igt_fb.c > +++ b/lib/igt_fb.c > @@ -3256,6 +3256,72 @@ bool igt_fb_supported_format(uint32_t drm_format) > return false; > } > > +/* > + * This implements the FNV-1a hashing algorithm instead of CRC, for > + * simplicity > + * http://www.isthe.com/chongo/tech/comp/fnv/index.html > + * > + * hash = offset_basis > + * for each octet_of_data to be hashed > + * hash = hash xor octet_of_data > + * hash = hash * FNV_prime > + * return hash > + * > + * 32 bit offset_basis = 2166136261 > + * 32 bit FNV_prime = 224 + 28 + 0x93 = 16777619 > + */ > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc) > +{ > +#define FNV1a_OFFSET_BIAS 2166136261 > +#define FNV1a_PRIME 16777619 I'd just use plain uint32_t variables for those, but no big deal. > + uint32_t hash; > + void *map; > + char *ptr, *line = NULL; > + int x, y, cpp = igt_drm_format_to_bpp(fb->drm_format) / 8; > + uint32_t stride = calc_plane_stride(fb, 0); We could return -EINVAL in case fb->num_planes != 1. > + if (fb->is_dumb) > + map = kmstest_dumb_map_buffer(fb->fd, fb->gem_handle, fb->size, > + PROT_READ); > + else > + map = gem_mmap__gtt(fb->fd, fb->gem_handle, fb->size, > + PROT_READ); > + ptr = map; Nit: no need for this, can assign the result of mmap directly to ptr. > + > + /* > + * Framebuffers are often uncached, which can make byte-wise accesses > + * very slow. We copy each line of the FB into a local buffer to speed > + * up the hashing. > + */ > + line = malloc(stride); > + if (!line) { > + munmap(map, fb->size); > + return -ENOMEM; > + } > + > + hash = FNV1a_OFFSET_BIAS; > + > + for (y = 0; y < fb->height; y++, ptr += stride) { > + > + igt_memcpy_from_wc(line, ptr, stride); Nit: no need to copy the whole stride actually, we can just copy fb->width * cpp since we're only going to read that. > + > + for (x = 0; x < fb->width * cpp; x++) { > + hash ^= line[x]; > + hash *= FNV1a_PRIME; > + } > + } > + > + crc->n_words = 1; > + crc->crc[0] = hash; > + > + free(line); > + munmap(map, fb->size); > + > + return 0; > +#undef FNV1a_OFFSET_BIAS > +#undef FNV1a_PRIME > +} > + > /** > * igt_format_is_yuv: > * @drm_format: drm fourcc > diff --git a/lib/igt_fb.h b/lib/igt_fb.h > index adefebe1..a2741c05 100644 > --- a/lib/igt_fb.h > +++ b/lib/igt_fb.h > @@ -37,6 +37,7 @@ > #include <i915_drm.h> > > #include "igt_color_encoding.h" > +#include "igt_debugfs.h" > > /* > * Internal format to denote a buffer compatible with pixman's > @@ -194,5 +195,7 @@ int igt_format_plane_bpp(uint32_t drm_format, int plane); > void igt_format_array_fill(uint32_t **formats_array, unsigned int *count, > bool allow_yuv); > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc); > + > #endif /* __IGT_FB_H__ */ > > _______________________________________________ > igt-dev mailing list > igt-dev@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/igt-dev
On Wed, 2019-07-10 at 15:30 +0000, Ser, Simon wrote: > Mostly LGTM, here are a few nits. > > On Wed, 2019-06-12 at 23:17 -0300, Brian Starkey wrote: > > To use writeback buffers as a CRC source, we need to be able to hash > > them. Implement a simple FVA-1a hashing routine for this purpose. > > > > Doing a bytewise hash on the framebuffer directly can be very slow if > > the memory is noncached. By making a copy of each line in the FB first > > (which can take advantage of word-access speedup), we can do the hash > > on a cached copy, which is much faster (10x speedup on my platform). > > > > v6: use igt_memcpy_from_wc() instead of plain memcpy, as suggested by > > Chris Wilson > > > > Signed-off-by: Brian Starkey <brian.starkey@arm.com> > > [rebased and updated to the most recent API] > > Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> > > --- > > lib/igt_fb.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > > lib/igt_fb.h | 3 +++ > > 2 files changed, 69 insertions(+) > > > > diff --git a/lib/igt_fb.c b/lib/igt_fb.c > > index 9d4f905e..d07dae39 100644 > > --- a/lib/igt_fb.c > > +++ b/lib/igt_fb.c > > @@ -3256,6 +3256,72 @@ bool igt_fb_supported_format(uint32_t drm_format) > > return false; > > } > > > > +/* > > + * This implements the FNV-1a hashing algorithm instead of CRC, for > > + * simplicity > > + * http://www.isthe.com/chongo/tech/comp/fnv/index.html > > + * > > + * hash = offset_basis > > + * for each octet_of_data to be hashed > > + * hash = hash xor octet_of_data > > + * hash = hash * FNV_prime > > + * return hash > > + * > > + * 32 bit offset_basis = 2166136261 > > + * 32 bit FNV_prime = 224 + 28 + 0x93 = 16777619 > > + */ > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc) > > +{ > > +#define FNV1a_OFFSET_BIAS 2166136261 > > +#define FNV1a_PRIME 16777619 > > I'd just use plain uint32_t variables for those, but no big deal. > > > + uint32_t hash; > > + void *map; > > + char *ptr, *line = NULL; > > + int x, y, cpp = igt_drm_format_to_bpp(fb->drm_format) / 8; > > + uint32_t stride = calc_plane_stride(fb, 0); > > We could return -EINVAL in case fb->num_planes != 1. Let's not waste cycles. With this ^ fixed, this patch is: Reviewed-by: Simon Ser <simon.ser@intel.com> Other nits are optional. > > + if (fb->is_dumb) > > + map = kmstest_dumb_map_buffer(fb->fd, fb->gem_handle, fb->size, > > + PROT_READ); > > + else > > + map = gem_mmap__gtt(fb->fd, fb->gem_handle, fb->size, > > + PROT_READ); > > + ptr = map; > > Nit: no need for this, can assign the result of mmap directly to ptr. > > > + > > + /* > > + * Framebuffers are often uncached, which can make byte-wise accesses > > + * very slow. We copy each line of the FB into a local buffer to speed > > + * up the hashing. > > + */ > > + line = malloc(stride); > > + if (!line) { > > + munmap(map, fb->size); > > + return -ENOMEM; > > + } > > + > > + hash = FNV1a_OFFSET_BIAS; > > + > > + for (y = 0; y < fb->height; y++, ptr += stride) { > > + > > + igt_memcpy_from_wc(line, ptr, stride); > > Nit: no need to copy the whole stride actually, we can just copy > fb->width * cpp since we're only going to read that. > > > + > > + for (x = 0; x < fb->width * cpp; x++) { > > + hash ^= line[x]; > > + hash *= FNV1a_PRIME; > > + } > > + } > > + > > + crc->n_words = 1; > > + crc->crc[0] = hash; > > + > > + free(line); > > + munmap(map, fb->size); > > + > > + return 0; > > +#undef FNV1a_OFFSET_BIAS > > +#undef FNV1a_PRIME > > +} > > + > > /** > > * igt_format_is_yuv: > > * @drm_format: drm fourcc > > diff --git a/lib/igt_fb.h b/lib/igt_fb.h > > index adefebe1..a2741c05 100644 > > --- a/lib/igt_fb.h > > +++ b/lib/igt_fb.h > > @@ -37,6 +37,7 @@ > > #include <i915_drm.h> > > > > #include "igt_color_encoding.h" > > +#include "igt_debugfs.h" > > > > /* > > * Internal format to denote a buffer compatible with pixman's > > @@ -194,5 +195,7 @@ int igt_format_plane_bpp(uint32_t drm_format, int plane); > > void igt_format_array_fill(uint32_t **formats_array, unsigned int *count, > > bool allow_yuv); > > > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc); > > + > > #endif /* __IGT_FB_H__ */ > > > > _______________________________________________ > > igt-dev mailing list > > igt-dev@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/igt-dev > _______________________________________________ > igt-dev mailing list > igt-dev@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/igt-dev
On 07/10, Ser, Simon wrote: > On Wed, 2019-07-10 at 15:30 +0000, Ser, Simon wrote: > > Mostly LGTM, here are a few nits. > > > > On Wed, 2019-06-12 at 23:17 -0300, Brian Starkey wrote: > > > To use writeback buffers as a CRC source, we need to be able to hash > > > them. Implement a simple FVA-1a hashing routine for this purpose. > > > > > > Doing a bytewise hash on the framebuffer directly can be very slow if > > > the memory is noncached. By making a copy of each line in the FB first > > > (which can take advantage of word-access speedup), we can do the hash > > > on a cached copy, which is much faster (10x speedup on my platform). > > > > > > v6: use igt_memcpy_from_wc() instead of plain memcpy, as suggested by > > > Chris Wilson > > > > > > Signed-off-by: Brian Starkey <brian.starkey@arm.com> > > > [rebased and updated to the most recent API] > > > Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> > > > --- > > > lib/igt_fb.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > lib/igt_fb.h | 3 +++ > > > 2 files changed, 69 insertions(+) > > > > > > diff --git a/lib/igt_fb.c b/lib/igt_fb.c > > > index 9d4f905e..d07dae39 100644 > > > --- a/lib/igt_fb.c > > > +++ b/lib/igt_fb.c > > > @@ -3256,6 +3256,72 @@ bool igt_fb_supported_format(uint32_t drm_format) > > > return false; > > > } > > > > > > +/* > > > + * This implements the FNV-1a hashing algorithm instead of CRC, for > > > + * simplicity > > > + * http://www.isthe.com/chongo/tech/comp/fnv/index.html > > > + * > > > + * hash = offset_basis > > > + * for each octet_of_data to be hashed > > > + * hash = hash xor octet_of_data > > > + * hash = hash * FNV_prime > > > + * return hash > > > + * > > > + * 32 bit offset_basis = 2166136261 > > > + * 32 bit FNV_prime = 224 + 28 + 0x93 = 16777619 > > > + */ > > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc) > > > +{ > > > +#define FNV1a_OFFSET_BIAS 2166136261 > > > +#define FNV1a_PRIME 16777619 > > > > I'd just use plain uint32_t variables for those, but no big deal. > > > > > + uint32_t hash; > > > + void *map; > > > + char *ptr, *line = NULL; > > > + int x, y, cpp = igt_drm_format_to_bpp(fb->drm_format) / 8; > > > + uint32_t stride = calc_plane_stride(fb, 0); > > > > We could return -EINVAL in case fb->num_planes != 1. > > Let's not waste cycles. With this ^ fixed, this patch is: > > Reviewed-by: Simon Ser <simon.ser@intel.com> > > Other nits are optional. I agreed with all your suggestions, and I already applied all of them. Should I wait for the other patches review, or should I resend the new version? Thanks for all the feedback Best Regards > > > + if (fb->is_dumb) > > > + map = kmstest_dumb_map_buffer(fb->fd, fb->gem_handle, fb->size, > > > + PROT_READ); > > > + else > > > + map = gem_mmap__gtt(fb->fd, fb->gem_handle, fb->size, > > > + PROT_READ); > > > + ptr = map; > > > > Nit: no need for this, can assign the result of mmap directly to ptr. > > > > > + > > > + /* > > > + * Framebuffers are often uncached, which can make byte-wise accesses > > > + * very slow. We copy each line of the FB into a local buffer to speed > > > + * up the hashing. > > > + */ > > > + line = malloc(stride); > > > + if (!line) { > > > + munmap(map, fb->size); > > > + return -ENOMEM; > > > + } > > > + > > > + hash = FNV1a_OFFSET_BIAS; > > > + > > > + for (y = 0; y < fb->height; y++, ptr += stride) { > > > + > > > + igt_memcpy_from_wc(line, ptr, stride); > > > > Nit: no need to copy the whole stride actually, we can just copy > > fb->width * cpp since we're only going to read that. > > > > > + > > > + for (x = 0; x < fb->width * cpp; x++) { > > > + hash ^= line[x]; > > > + hash *= FNV1a_PRIME; > > > + } > > > + } > > > + > > > + crc->n_words = 1; > > > + crc->crc[0] = hash; > > > + > > > + free(line); > > > + munmap(map, fb->size); > > > + > > > + return 0; > > > +#undef FNV1a_OFFSET_BIAS > > > +#undef FNV1a_PRIME > > > +} > > > + > > > /** > > > * igt_format_is_yuv: > > > * @drm_format: drm fourcc > > > diff --git a/lib/igt_fb.h b/lib/igt_fb.h > > > index adefebe1..a2741c05 100644 > > > --- a/lib/igt_fb.h > > > +++ b/lib/igt_fb.h > > > @@ -37,6 +37,7 @@ > > > #include <i915_drm.h> > > > > > > #include "igt_color_encoding.h" > > > +#include "igt_debugfs.h" > > > > > > /* > > > * Internal format to denote a buffer compatible with pixman's > > > @@ -194,5 +195,7 @@ int igt_format_plane_bpp(uint32_t drm_format, int plane); > > > void igt_format_array_fill(uint32_t **formats_array, unsigned int *count, > > > bool allow_yuv); > > > > > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc); > > > + > > > #endif /* __IGT_FB_H__ */ > > > > > > _______________________________________________ > > > igt-dev mailing list > > > igt-dev@lists.freedesktop.org > > > https://lists.freedesktop.org/mailman/listinfo/igt-dev > > _______________________________________________ > > igt-dev mailing list > > igt-dev@lists.freedesktop.org > > https://lists.freedesktop.org/mailman/listinfo/igt-dev
On Thu, 2019-07-11 at 23:49 -0300, Rodrigo Siqueira wrote: > On 07/10, Ser, Simon wrote: > > On Wed, 2019-07-10 at 15:30 +0000, Ser, Simon wrote: > > > Mostly LGTM, here are a few nits. > > > > > > On Wed, 2019-06-12 at 23:17 -0300, Brian Starkey wrote: > > > > To use writeback buffers as a CRC source, we need to be able to hash > > > > them. Implement a simple FVA-1a hashing routine for this purpose. > > > > > > > > Doing a bytewise hash on the framebuffer directly can be very slow if > > > > the memory is noncached. By making a copy of each line in the FB first > > > > (which can take advantage of word-access speedup), we can do the hash > > > > on a cached copy, which is much faster (10x speedup on my platform). > > > > > > > > v6: use igt_memcpy_from_wc() instead of plain memcpy, as suggested by > > > > Chris Wilson > > > > > > > > Signed-off-by: Brian Starkey <brian.starkey@arm.com> > > > > [rebased and updated to the most recent API] > > > > Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> > > > > --- > > > > lib/igt_fb.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > > lib/igt_fb.h | 3 +++ > > > > 2 files changed, 69 insertions(+) > > > > > > > > diff --git a/lib/igt_fb.c b/lib/igt_fb.c > > > > index 9d4f905e..d07dae39 100644 > > > > --- a/lib/igt_fb.c > > > > +++ b/lib/igt_fb.c > > > > @@ -3256,6 +3256,72 @@ bool igt_fb_supported_format(uint32_t drm_format) > > > > return false; > > > > } > > > > > > > > +/* > > > > + * This implements the FNV-1a hashing algorithm instead of CRC, for > > > > + * simplicity > > > > + * http://www.isthe.com/chongo/tech/comp/fnv/index.html > > > > + * > > > > + * hash = offset_basis > > > > + * for each octet_of_data to be hashed > > > > + * hash = hash xor octet_of_data > > > > + * hash = hash * FNV_prime > > > > + * return hash > > > > + * > > > > + * 32 bit offset_basis = 2166136261 > > > > + * 32 bit FNV_prime = 224 + 28 + 0x93 = 16777619 > > > > + */ > > > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc) > > > > +{ > > > > +#define FNV1a_OFFSET_BIAS 2166136261 > > > > +#define FNV1a_PRIME 16777619 > > > > > > I'd just use plain uint32_t variables for those, but no big deal. > > > > > > > + uint32_t hash; > > > > + void *map; > > > > + char *ptr, *line = NULL; > > > > + int x, y, cpp = igt_drm_format_to_bpp(fb->drm_format) / 8; > > > > + uint32_t stride = calc_plane_stride(fb, 0); > > > > > > We could return -EINVAL in case fb->num_planes != 1. > > > > Let's not waste cycles. With this ^ fixed, this patch is: > > > > Reviewed-by: Simon Ser <simon.ser@intel.com> > > > > Other nits are optional. > > I agreed with all your suggestions, and I already applied all of them. > Should I wait for the other patches review, or should I resend the new > version? I'm fine with waiting for the full review before a new version of the whole patchset, but you can also send an updated version of a single patch with: git send-email --in-reply-to="<cover.1560374714.git.rodrigosiqueiramelo@gmail.com>" -1 <commit hash> where In-Reply-To is the Message-Id of the patch you want to update. I agree it's a little tedious since you need to extract the Message-Id from the message header. > Thanks for all the feedback :) > Best Regards > > > > > + if (fb->is_dumb) > > > > + map = kmstest_dumb_map_buffer(fb->fd, fb->gem_handle, fb->size, > > > > + PROT_READ); > > > > + else > > > > + map = gem_mmap__gtt(fb->fd, fb->gem_handle, fb->size, > > > > + PROT_READ); > > > > + ptr = map; > > > > > > Nit: no need for this, can assign the result of mmap directly to ptr. > > > > > > > + > > > > + /* > > > > + * Framebuffers are often uncached, which can make byte-wise accesses > > > > + * very slow. We copy each line of the FB into a local buffer to speed > > > > + * up the hashing. > > > > + */ > > > > + line = malloc(stride); > > > > + if (!line) { > > > > + munmap(map, fb->size); > > > > + return -ENOMEM; > > > > + } > > > > + > > > > + hash = FNV1a_OFFSET_BIAS; > > > > + > > > > + for (y = 0; y < fb->height; y++, ptr += stride) { > > > > + > > > > + igt_memcpy_from_wc(line, ptr, stride); > > > > > > Nit: no need to copy the whole stride actually, we can just copy > > > fb->width * cpp since we're only going to read that. > > > > > > > + > > > > + for (x = 0; x < fb->width * cpp; x++) { > > > > + hash ^= line[x]; > > > > + hash *= FNV1a_PRIME; > > > > + } > > > > + } > > > > + > > > > + crc->n_words = 1; > > > > + crc->crc[0] = hash; > > > > + > > > > + free(line); > > > > + munmap(map, fb->size); > > > > + > > > > + return 0; > > > > +#undef FNV1a_OFFSET_BIAS > > > > +#undef FNV1a_PRIME > > > > +} > > > > + > > > > /** > > > > * igt_format_is_yuv: > > > > * @drm_format: drm fourcc > > > > diff --git a/lib/igt_fb.h b/lib/igt_fb.h > > > > index adefebe1..a2741c05 100644 > > > > --- a/lib/igt_fb.h > > > > +++ b/lib/igt_fb.h > > > > @@ -37,6 +37,7 @@ > > > > #include <i915_drm.h> > > > > > > > > #include "igt_color_encoding.h" > > > > +#include "igt_debugfs.h" > > > > > > > > /* > > > > * Internal format to denote a buffer compatible with pixman's > > > > @@ -194,5 +195,7 @@ int igt_format_plane_bpp(uint32_t drm_format, int plane); > > > > void igt_format_array_fill(uint32_t **formats_array, unsigned int *count, > > > > bool allow_yuv); > > > > > > > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc); > > > > + > > > > #endif /* __IGT_FB_H__ */ > > > > > > > > _______________________________________________ > > > > igt-dev mailing list > > > > igt-dev@lists.freedesktop.org > > > > https://lists.freedesktop.org/mailman/listinfo/igt-dev > > > _______________________________________________ > > > igt-dev mailing list > > > igt-dev@lists.freedesktop.org > > > https://lists.freedesktop.org/mailman/listinfo/igt-dev
On 07/12, Ser, Simon wrote: > On Thu, 2019-07-11 at 23:49 -0300, Rodrigo Siqueira wrote: > > On 07/10, Ser, Simon wrote: > > > On Wed, 2019-07-10 at 15:30 +0000, Ser, Simon wrote: > > > > Mostly LGTM, here are a few nits. > > > > > > > > On Wed, 2019-06-12 at 23:17 -0300, Brian Starkey wrote: > > > > > To use writeback buffers as a CRC source, we need to be able to hash > > > > > them. Implement a simple FVA-1a hashing routine for this purpose. > > > > > > > > > > Doing a bytewise hash on the framebuffer directly can be very slow if > > > > > the memory is noncached. By making a copy of each line in the FB first > > > > > (which can take advantage of word-access speedup), we can do the hash > > > > > on a cached copy, which is much faster (10x speedup on my platform). > > > > > > > > > > v6: use igt_memcpy_from_wc() instead of plain memcpy, as suggested by > > > > > Chris Wilson > > > > > > > > > > Signed-off-by: Brian Starkey <brian.starkey@arm.com> > > > > > [rebased and updated to the most recent API] > > > > > Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> > > > > > --- > > > > > lib/igt_fb.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ > > > > > lib/igt_fb.h | 3 +++ > > > > > 2 files changed, 69 insertions(+) > > > > > > > > > > diff --git a/lib/igt_fb.c b/lib/igt_fb.c > > > > > index 9d4f905e..d07dae39 100644 > > > > > --- a/lib/igt_fb.c > > > > > +++ b/lib/igt_fb.c > > > > > @@ -3256,6 +3256,72 @@ bool igt_fb_supported_format(uint32_t drm_format) > > > > > return false; > > > > > } > > > > > > > > > > +/* > > > > > + * This implements the FNV-1a hashing algorithm instead of CRC, for > > > > > + * simplicity > > > > > + * http://www.isthe.com/chongo/tech/comp/fnv/index.html > > > > > + * > > > > > + * hash = offset_basis > > > > > + * for each octet_of_data to be hashed > > > > > + * hash = hash xor octet_of_data > > > > > + * hash = hash * FNV_prime > > > > > + * return hash > > > > > + * > > > > > + * 32 bit offset_basis = 2166136261 > > > > > + * 32 bit FNV_prime = 224 + 28 + 0x93 = 16777619 > > > > > + */ > > > > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc) > > > > > +{ > > > > > +#define FNV1a_OFFSET_BIAS 2166136261 > > > > > +#define FNV1a_PRIME 16777619 > > > > > > > > I'd just use plain uint32_t variables for those, but no big deal. > > > > > > > > > + uint32_t hash; > > > > > + void *map; > > > > > + char *ptr, *line = NULL; > > > > > + int x, y, cpp = igt_drm_format_to_bpp(fb->drm_format) / 8; > > > > > + uint32_t stride = calc_plane_stride(fb, 0); > > > > > > > > We could return -EINVAL in case fb->num_planes != 1. > > > > > > Let's not waste cycles. With this ^ fixed, this patch is: > > > > > > Reviewed-by: Simon Ser <simon.ser@intel.com> > > > > > > Other nits are optional. > > > > I agreed with all your suggestions, and I already applied all of them. > > Should I wait for the other patches review, or should I resend the new > > version? > > I'm fine with waiting for the full review before a new version of the > whole patchset, but you can also send an updated version of a single > patch with: > > git send-email --in-reply-to="<cover.1560374714.git.rodrigosiqueiramelo@gmail.com>" -1 <commit hash> > > where In-Reply-To is the Message-Id of the patch you want to update. I > agree it's a little tedious since you need to extract the Message-Id > from the message header. Thanks for the tip with git-send-mail. Since I already applied most of your suggestions, I'll send a full version soon. > > Thanks for all the feedback > > :) > > > Best Regards > > > > > > > + if (fb->is_dumb) > > > > > + map = kmstest_dumb_map_buffer(fb->fd, fb->gem_handle, fb->size, > > > > > + PROT_READ); > > > > > + else > > > > > + map = gem_mmap__gtt(fb->fd, fb->gem_handle, fb->size, > > > > > + PROT_READ); > > > > > + ptr = map; > > > > > > > > Nit: no need for this, can assign the result of mmap directly to ptr. > > > > > > > > > + > > > > > + /* > > > > > + * Framebuffers are often uncached, which can make byte-wise accesses > > > > > + * very slow. We copy each line of the FB into a local buffer to speed > > > > > + * up the hashing. > > > > > + */ > > > > > + line = malloc(stride); > > > > > + if (!line) { > > > > > + munmap(map, fb->size); > > > > > + return -ENOMEM; > > > > > + } > > > > > + > > > > > + hash = FNV1a_OFFSET_BIAS; > > > > > + > > > > > + for (y = 0; y < fb->height; y++, ptr += stride) { > > > > > + > > > > > + igt_memcpy_from_wc(line, ptr, stride); > > > > > > > > Nit: no need to copy the whole stride actually, we can just copy > > > > fb->width * cpp since we're only going to read that. > > > > > > > > > + > > > > > + for (x = 0; x < fb->width * cpp; x++) { > > > > > + hash ^= line[x]; > > > > > + hash *= FNV1a_PRIME; > > > > > + } > > > > > + } > > > > > + > > > > > + crc->n_words = 1; > > > > > + crc->crc[0] = hash; > > > > > + > > > > > + free(line); > > > > > + munmap(map, fb->size); > > > > > + > > > > > + return 0; > > > > > +#undef FNV1a_OFFSET_BIAS > > > > > +#undef FNV1a_PRIME > > > > > +} > > > > > + > > > > > /** > > > > > * igt_format_is_yuv: > > > > > * @drm_format: drm fourcc > > > > > diff --git a/lib/igt_fb.h b/lib/igt_fb.h > > > > > index adefebe1..a2741c05 100644 > > > > > --- a/lib/igt_fb.h > > > > > +++ b/lib/igt_fb.h > > > > > @@ -37,6 +37,7 @@ > > > > > #include <i915_drm.h> > > > > > > > > > > #include "igt_color_encoding.h" > > > > > +#include "igt_debugfs.h" > > > > > > > > > > /* > > > > > * Internal format to denote a buffer compatible with pixman's > > > > > @@ -194,5 +195,7 @@ int igt_format_plane_bpp(uint32_t drm_format, int plane); > > > > > void igt_format_array_fill(uint32_t **formats_array, unsigned int *count, > > > > > bool allow_yuv); > > > > > > > > > > +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc); > > > > > + > > > > > #endif /* __IGT_FB_H__ */ > > > > > > > > > > _______________________________________________ > > > > > igt-dev mailing list > > > > > igt-dev@lists.freedesktop.org > > > > > https://lists.freedesktop.org/mailman/listinfo/igt-dev > > > > _______________________________________________ > > > > igt-dev mailing list > > > > igt-dev@lists.freedesktop.org > > > > https://lists.freedesktop.org/mailman/listinfo/igt-dev
diff --git a/lib/igt_fb.c b/lib/igt_fb.c index 9d4f905e..d07dae39 100644 --- a/lib/igt_fb.c +++ b/lib/igt_fb.c @@ -3256,6 +3256,72 @@ bool igt_fb_supported_format(uint32_t drm_format) return false; } +/* + * This implements the FNV-1a hashing algorithm instead of CRC, for + * simplicity + * http://www.isthe.com/chongo/tech/comp/fnv/index.html + * + * hash = offset_basis + * for each octet_of_data to be hashed + * hash = hash xor octet_of_data + * hash = hash * FNV_prime + * return hash + * + * 32 bit offset_basis = 2166136261 + * 32 bit FNV_prime = 224 + 28 + 0x93 = 16777619 + */ +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc) +{ +#define FNV1a_OFFSET_BIAS 2166136261 +#define FNV1a_PRIME 16777619 + uint32_t hash; + void *map; + char *ptr, *line = NULL; + int x, y, cpp = igt_drm_format_to_bpp(fb->drm_format) / 8; + uint32_t stride = calc_plane_stride(fb, 0); + + if (fb->is_dumb) + map = kmstest_dumb_map_buffer(fb->fd, fb->gem_handle, fb->size, + PROT_READ); + else + map = gem_mmap__gtt(fb->fd, fb->gem_handle, fb->size, + PROT_READ); + ptr = map; + + /* + * Framebuffers are often uncached, which can make byte-wise accesses + * very slow. We copy each line of the FB into a local buffer to speed + * up the hashing. + */ + line = malloc(stride); + if (!line) { + munmap(map, fb->size); + return -ENOMEM; + } + + hash = FNV1a_OFFSET_BIAS; + + for (y = 0; y < fb->height; y++, ptr += stride) { + + igt_memcpy_from_wc(line, ptr, stride); + + for (x = 0; x < fb->width * cpp; x++) { + hash ^= line[x]; + hash *= FNV1a_PRIME; + } + } + + crc->n_words = 1; + crc->crc[0] = hash; + + free(line); + munmap(map, fb->size); + + return 0; +#undef FNV1a_OFFSET_BIAS +#undef FNV1a_PRIME +} + /** * igt_format_is_yuv: * @drm_format: drm fourcc diff --git a/lib/igt_fb.h b/lib/igt_fb.h index adefebe1..a2741c05 100644 --- a/lib/igt_fb.h +++ b/lib/igt_fb.h @@ -37,6 +37,7 @@ #include <i915_drm.h> #include "igt_color_encoding.h" +#include "igt_debugfs.h" /* * Internal format to denote a buffer compatible with pixman's @@ -194,5 +195,7 @@ int igt_format_plane_bpp(uint32_t drm_format, int plane); void igt_format_array_fill(uint32_t **formats_array, unsigned int *count, bool allow_yuv); +int igt_fb_get_crc(struct igt_fb *fb, igt_crc_t *crc); + #endif /* __IGT_FB_H__ */
To use writeback buffers as a CRC source, we need to be able to hash them. Implement a simple FVA-1a hashing routine for this purpose. Doing a bytewise hash on the framebuffer directly can be very slow if the memory is noncached. By making a copy of each line in the FB first (which can take advantage of word-access speedup), we can do the hash on a cached copy, which is much faster (10x speedup on my platform). v6: use igt_memcpy_from_wc() instead of plain memcpy, as suggested by Chris Wilson Signed-off-by: Brian Starkey <brian.starkey@arm.com> [rebased and updated to the most recent API] Signed-off-by: Liviu Dudau <liviu.dudau@arm.com> --- lib/igt_fb.c | 66 ++++++++++++++++++++++++++++++++++++++++++++++++++++ lib/igt_fb.h | 3 +++ 2 files changed, 69 insertions(+)