From 0a97015d45ee4d5b1d0b93596e8319c9c2ecdb5b Mon Sep 17 00:00:00 2001 From: Chris Wilson Date: Wed, 12 Oct 2016 10:05:22 +0100 Subject: [PATCH] drm/i915: Compress GPU objects in error state Our error states are quickly growing, pinning kernel memory with them. The majority of the space is taken up by the error objects. These compress well using zlib and without decode are mostly meaningless, so encoding them does not hinder quickly parsing the error state for familiarity. v2: Make the zlib dependency optional Signed-off-by: Chris Wilson Reviewed-by: Joonas Lahtinen Link: http://patchwork.freedesktop.org/patch/msgid/20161012090522.367-6-chris@chris-wilson.co.uk --- drivers/gpu/drm/i915/Kconfig | 12 ++ drivers/gpu/drm/i915/i915_drv.h | 3 +- drivers/gpu/drm/i915/i915_gpu_error.c | 176 +++++++++++++++++++++++--- 3 files changed, 169 insertions(+), 22 deletions(-) diff --git a/drivers/gpu/drm/i915/Kconfig b/drivers/gpu/drm/i915/Kconfig index 3eff42e4a441..6aedc96aa412 100644 --- a/drivers/gpu/drm/i915/Kconfig +++ b/drivers/gpu/drm/i915/Kconfig @@ -60,6 +60,18 @@ config DRM_I915_CAPTURE_ERROR If in doubt, say "Y". +config DRM_I915_COMPRESS_ERROR + bool "Compress GPU error state" + depends on DRM_I915_CAPTURE_ERROR + select ZLIB_DEFLATE + default y + help + This option selects ZLIB_DEFLATE if it isn't already + selected and causes any error state captured upon a GPU hang + to be compressed using zlib. + + If in doubt, say "Y". + config DRM_I915_USERPTR bool "Always enable userptr support" depends on DRM_I915 diff --git a/drivers/gpu/drm/i915/i915_drv.h b/drivers/gpu/drm/i915/i915_drv.h index 4199e8aa436a..bf397b643cc0 100644 --- a/drivers/gpu/drm/i915/i915_drv.h +++ b/drivers/gpu/drm/i915/i915_drv.h @@ -820,9 +820,10 @@ struct drm_i915_error_state { struct intel_instdone instdone; struct drm_i915_error_object { - int page_count; u64 gtt_offset; u64 gtt_size; + int page_count; + int unused; u32 *pages[0]; } *ringbuffer, *batchbuffer, *wa_batchbuffer, *ctx, *hws_page; diff --git a/drivers/gpu/drm/i915/i915_gpu_error.c b/drivers/gpu/drm/i915/i915_gpu_error.c index 22bd2187ea37..78cc13b9b2a5 100644 --- a/drivers/gpu/drm/i915/i915_gpu_error.c +++ b/drivers/gpu/drm/i915/i915_gpu_error.c @@ -29,6 +29,7 @@ #include #include +#include #include "i915_drv.h" static const char *engine_str(int engine) @@ -173,6 +174,110 @@ static void i915_error_puts(struct drm_i915_error_state_buf *e, #define err_printf(e, ...) i915_error_printf(e, __VA_ARGS__) #define err_puts(e, s) i915_error_puts(e, s) +#ifdef CONFIG_DRM_I915_COMPRESS_ERROR + +static bool compress_init(struct z_stream_s *zstream) +{ + memset(zstream, 0, sizeof(*zstream)); + + zstream->workspace = + kmalloc(zlib_deflate_workspacesize(MAX_WBITS, MAX_MEM_LEVEL), + GFP_ATOMIC | __GFP_NOWARN); + if (!zstream->workspace) + return false; + + if (zlib_deflateInit(zstream, Z_DEFAULT_COMPRESSION) != Z_OK) { + kfree(zstream->workspace); + return false; + } + + return true; +} + +static int compress_page(struct z_stream_s *zstream, + void *src, + struct drm_i915_error_object *dst) +{ + zstream->next_in = src; + zstream->avail_in = PAGE_SIZE; + + do { + if (zstream->avail_out == 0) { + unsigned long page; + + page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN); + if (!page) + return -ENOMEM; + + dst->pages[dst->page_count++] = (void *)page; + + zstream->next_out = (void *)page; + zstream->avail_out = PAGE_SIZE; + } + + if (zlib_deflate(zstream, Z_SYNC_FLUSH) != Z_OK) + return -EIO; + } while (zstream->avail_in); + + /* Fallback to uncompressed if we increase size? */ + if (0 && zstream->total_out > zstream->total_in) + return -E2BIG; + + return 0; +} + +static void compress_fini(struct z_stream_s *zstream, + struct drm_i915_error_object *dst) +{ + if (dst) { + zlib_deflate(zstream, Z_FINISH); + dst->unused = zstream->avail_out; + } + + zlib_deflateEnd(zstream); + kfree(zstream->workspace); +} + +static void err_compression_marker(struct drm_i915_error_state_buf *m) +{ + err_puts(m, ":"); +} + +#else + +static bool compress_init(struct z_stream_s *zstream) +{ + return true; +} + +static int compress_page(struct z_stream_s *zstream, + void *src, + struct drm_i915_error_object *dst) +{ + unsigned long page; + + page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN); + if (!page) + return -ENOMEM; + + dst->pages[dst->page_count++] = + memcpy((void *)page, src, PAGE_SIZE); + + return 0; +} + +static void compress_fini(struct z_stream_s *zstream, + struct drm_i915_error_object *dst) +{ +} + +static void err_compression_marker(struct drm_i915_error_state_buf *m) +{ + err_puts(m, "~"); +} + +#endif + static void print_error_buffers(struct drm_i915_error_state_buf *m, const char *name, struct drm_i915_error_buffer *err, @@ -340,12 +445,36 @@ void i915_error_printf(struct drm_i915_error_state_buf *e, const char *f, ...) va_end(args); } +static int +ascii85_encode_len(int len) +{ + return DIV_ROUND_UP(len, 4); +} + +static bool +ascii85_encode(u32 in, char *out) +{ + int i; + + if (in == 0) + return false; + + out[5] = '\0'; + for (i = 5; i--; ) { + out[i] = '!' + in % 85; + in /= 85; + } + + return true; +} + static void print_error_obj(struct drm_i915_error_state_buf *m, struct intel_engine_cs *engine, const char *name, struct drm_i915_error_object *obj) { - int page, offset, elt; + char out[6]; + int page; if (!obj) return; @@ -357,13 +486,23 @@ static void print_error_obj(struct drm_i915_error_state_buf *m, lower_32_bits(obj->gtt_offset)); } - for (page = offset = 0; page < obj->page_count; page++) { - for (elt = 0; elt < PAGE_SIZE/4; elt++) { - err_printf(m, "%08x : %08x\n", offset, - obj->pages[page][elt]); - offset += 4; + err_compression_marker(m); + for (page = 0; page < obj->page_count; page++) { + int i, len; + + len = PAGE_SIZE; + if (page == obj->page_count - 1) + len -= obj->unused; + len = ascii85_encode_len(len); + + for (i = 0; i < len; i++) { + if (ascii85_encode(obj->pages[page][i], out)) + err_puts(m, out); + else + err_puts(m, "z"); } } + err_puts(m, "\n"); } static void err_print_capabilities(struct drm_i915_error_state_buf *m, @@ -643,20 +782,6 @@ static void i915_error_state_free(struct kref *error_ref) kfree(error); } -static int compress_page(void *src, struct drm_i915_error_object *dst) -{ - unsigned long page; - - page = __get_free_page(GFP_ATOMIC | __GFP_NOWARN); - if (!page) - return -ENOMEM; - - dst->pages[dst->page_count++] = (void *)page; - - memcpy((void *)page, src, PAGE_SIZE); - return 0; -} - static struct drm_i915_error_object * i915_error_object_create(struct drm_i915_private *i915, struct i915_vma *vma) @@ -664,6 +789,7 @@ i915_error_object_create(struct drm_i915_private *i915, struct i915_ggtt *ggtt = &i915->ggtt; const u64 slot = ggtt->error_capture.start; struct drm_i915_error_object *dst; + struct z_stream_s zstream; unsigned long num_pages; struct sgt_iter iter; dma_addr_t dma; @@ -672,6 +798,7 @@ i915_error_object_create(struct drm_i915_private *i915, return NULL; num_pages = min_t(u64, vma->size, vma->obj->base.size) >> PAGE_SHIFT; + num_pages = DIV_ROUND_UP(10 * num_pages, 8); /* worstcase zlib growth */ dst = kmalloc(sizeof(*dst) + num_pages * sizeof(u32 *), GFP_ATOMIC | __GFP_NOWARN); if (!dst) @@ -680,6 +807,12 @@ i915_error_object_create(struct drm_i915_private *i915, dst->gtt_offset = vma->node.start; dst->gtt_size = vma->node.size; dst->page_count = 0; + dst->unused = 0; + + if (!compress_init(&zstream)) { + kfree(dst); + return NULL; + } for_each_sgt_dma(dma, iter, vma->pages) { void __iomem *s; @@ -689,7 +822,7 @@ i915_error_object_create(struct drm_i915_private *i915, I915_CACHE_NONE, 0); s = io_mapping_map_atomic_wc(&ggtt->mappable, slot); - ret = compress_page((void * __force)s, dst); + ret = compress_page(&zstream, (void __force *)s, dst); io_mapping_unmap_atomic(s); if (ret) @@ -704,6 +837,7 @@ unwind: dst = NULL; out: + compress_fini(&zstream, dst); ggtt->base.clear_range(&ggtt->base, slot, PAGE_SIZE, true); return dst; } -- 2.20.1