From: Chris Wilson Date: Mon, 13 Feb 2017 17:15:13 +0000 (+0000) Subject: drm/i915: Add some selftests for sg_table manipulation X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=935a2f776aa5;p=GitHub%2Fmoto-9609%2Fandroid_kernel_motorola_exynos9610.git drm/i915: Add some selftests for sg_table manipulation Start exercising the scattergather lists, especially looking at iteration after coalescing. v2: Comment on the peculiarity of table construction (i.e. why this sg_table might be interesting). v3: Added one __func__ to identify expect_pfn_sg() v4: Loop until we have crossed the chain boundary (forcing sg_table to do multiple allocations) before squelching a potential ENOMEM from oom. Signed-off-by: Chris Wilson Cc: Tvrtko Ursulin Reviewed-by: Tvrtko Ursulin Link: http://patchwork.freedesktop.org/patch/msgid/20170213171558.20942-2-chris@chris-wilson.co.uk --- diff --git a/drivers/gpu/drm/i915/i915_gem.c b/drivers/gpu/drm/i915/i915_gem.c index 638b335e72b6..c91e5d10cc58 100644 --- a/drivers/gpu/drm/i915/i915_gem.c +++ b/drivers/gpu/drm/i915/i915_gem.c @@ -2224,17 +2224,17 @@ unlock: mutex_unlock(&obj->mm.lock); } -static void i915_sg_trim(struct sg_table *orig_st) +static bool i915_sg_trim(struct sg_table *orig_st) { struct sg_table new_st; struct scatterlist *sg, *new_sg; unsigned int i; if (orig_st->nents == orig_st->orig_nents) - return; + return false; if (sg_alloc_table(&new_st, orig_st->nents, GFP_KERNEL | __GFP_NOWARN)) - return; + return false; new_sg = new_st.sgl; for_each_sg(orig_st->sgl, sg, orig_st->nents, i) { @@ -2247,6 +2247,7 @@ static void i915_sg_trim(struct sg_table *orig_st) sg_free_table(orig_st); *orig_st = new_st; + return true; } static struct sg_table * @@ -5019,3 +5020,7 @@ i915_gem_object_get_dma_address(struct drm_i915_gem_object *obj, sg = i915_gem_object_get_sg(obj, n, &offset); return sg_dma_address(sg) + (offset << PAGE_SHIFT); } + +#if IS_ENABLED(CONFIG_DRM_I915_SELFTEST) +#include "selftests/scatterlist.c" +#endif diff --git a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h index 69e97a2ba4a6..5f0bdda42ed8 100644 --- a/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h +++ b/drivers/gpu/drm/i915/selftests/i915_mock_selftests.h @@ -9,3 +9,4 @@ * Tests are executed in order by igt/drv_selftest */ selftest(sanitycheck, i915_mock_sanitycheck) /* keep first (igt selfcheck) */ +selftest(scatterlist, scatterlist_mock_selftests) diff --git a/drivers/gpu/drm/i915/selftests/scatterlist.c b/drivers/gpu/drm/i915/selftests/scatterlist.c new file mode 100644 index 000000000000..eb2cda8e2b9f --- /dev/null +++ b/drivers/gpu/drm/i915/selftests/scatterlist.c @@ -0,0 +1,355 @@ +/* + * Copyright © 2016 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include +#include + +#include "../i915_selftest.h" + +#define PFN_BIAS (1 << 10) + +struct pfn_table { + struct sg_table st; + unsigned long start, end; +}; + +typedef unsigned int (*npages_fn_t)(unsigned long n, + unsigned long count, + struct rnd_state *rnd); + +static noinline int expect_pfn_sg(struct pfn_table *pt, + npages_fn_t npages_fn, + struct rnd_state *rnd, + const char *who, + unsigned long timeout) +{ + struct scatterlist *sg; + unsigned long pfn, n; + + pfn = pt->start; + for_each_sg(pt->st.sgl, sg, pt->st.nents, n) { + struct page *page = sg_page(sg); + unsigned int npages = npages_fn(n, pt->st.nents, rnd); + + if (page_to_pfn(page) != pfn) { + pr_err("%s: %s left pages out of order, expected pfn %lu, found pfn %lu (using for_each_sg)\n", + __func__, who, pfn, page_to_pfn(page)); + return -EINVAL; + } + + if (sg->length != npages * PAGE_SIZE) { + pr_err("%s: %s copied wrong sg length, expected size %lu, found %u (using for_each_sg)\n", + __func__, who, npages * PAGE_SIZE, sg->length); + return -EINVAL; + } + + if (igt_timeout(timeout, "%s timed out\n", who)) + return -EINTR; + + pfn += npages; + } + if (pfn != pt->end) { + pr_err("%s: %s finished on wrong pfn, expected %lu, found %lu\n", + __func__, who, pt->end, pfn); + return -EINVAL; + } + + return 0; +} + +static noinline int expect_pfn_sg_page_iter(struct pfn_table *pt, + const char *who, + unsigned long timeout) +{ + struct sg_page_iter sgiter; + unsigned long pfn; + + pfn = pt->start; + for_each_sg_page(pt->st.sgl, &sgiter, pt->st.nents, 0) { + struct page *page = sg_page_iter_page(&sgiter); + + if (page != pfn_to_page(pfn)) { + pr_err("%s: %s left pages out of order, expected pfn %lu, found pfn %lu (using for_each_sg_page)\n", + __func__, who, pfn, page_to_pfn(page)); + return -EINVAL; + } + + if (igt_timeout(timeout, "%s timed out\n", who)) + return -EINTR; + + pfn++; + } + if (pfn != pt->end) { + pr_err("%s: %s finished on wrong pfn, expected %lu, found %lu\n", + __func__, who, pt->end, pfn); + return -EINVAL; + } + + return 0; +} + +static noinline int expect_pfn_sgtiter(struct pfn_table *pt, + const char *who, + unsigned long timeout) +{ + struct sgt_iter sgt; + struct page *page; + unsigned long pfn; + + pfn = pt->start; + for_each_sgt_page(page, sgt, &pt->st) { + if (page != pfn_to_page(pfn)) { + pr_err("%s: %s left pages out of order, expected pfn %lu, found pfn %lu (using for_each_sgt_page)\n", + __func__, who, pfn, page_to_pfn(page)); + return -EINVAL; + } + + if (igt_timeout(timeout, "%s timed out\n", who)) + return -EINTR; + + pfn++; + } + if (pfn != pt->end) { + pr_err("%s: %s finished on wrong pfn, expected %lu, found %lu\n", + __func__, who, pt->end, pfn); + return -EINVAL; + } + + return 0; +} + +static int expect_pfn_sgtable(struct pfn_table *pt, + npages_fn_t npages_fn, + struct rnd_state *rnd, + const char *who, + unsigned long timeout) +{ + int err; + + err = expect_pfn_sg(pt, npages_fn, rnd, who, timeout); + if (err) + return err; + + err = expect_pfn_sg_page_iter(pt, who, timeout); + if (err) + return err; + + err = expect_pfn_sgtiter(pt, who, timeout); + if (err) + return err; + + return 0; +} + +static unsigned int one(unsigned long n, + unsigned long count, + struct rnd_state *rnd) +{ + return 1; +} + +static unsigned int grow(unsigned long n, + unsigned long count, + struct rnd_state *rnd) +{ + return n + 1; +} + +static unsigned int shrink(unsigned long n, + unsigned long count, + struct rnd_state *rnd) +{ + return count - n; +} + +static unsigned int random(unsigned long n, + unsigned long count, + struct rnd_state *rnd) +{ + return 1 + (prandom_u32_state(rnd) % 1024); +} + +static int alloc_table(struct pfn_table *pt, + unsigned long count, unsigned long max, + npages_fn_t npages_fn, + struct rnd_state *rnd, + int alloc_error) +{ + struct scatterlist *sg; + unsigned long n, pfn; + + if (sg_alloc_table(&pt->st, max, + GFP_KERNEL | __GFP_NORETRY | __GFP_NOWARN)) + return alloc_error; + + /* count should be less than 20 to prevent overflowing sg->length */ + GEM_BUG_ON(overflows_type(count * PAGE_SIZE, sg->length)); + + /* Construct a table where each scatterlist contains different number + * of entries. The idea is to check that we can iterate the individual + * pages from inside the coalesced lists. + */ + pt->start = PFN_BIAS; + pfn = pt->start; + sg = pt->st.sgl; + for (n = 0; n < count; n++) { + unsigned long npages = npages_fn(n, count, rnd); + + /* Nobody expects the Sparse Memmap! */ + if (pfn_to_page(pfn + npages) != pfn_to_page(pfn) + npages) { + sg_free_table(&pt->st); + return -ENOSPC; + } + + if (n) + sg = sg_next(sg); + sg_set_page(sg, pfn_to_page(pfn), npages * PAGE_SIZE, 0); + + GEM_BUG_ON(page_to_pfn(sg_page(sg)) != pfn); + GEM_BUG_ON(sg->length != npages * PAGE_SIZE); + GEM_BUG_ON(sg->offset != 0); + + pfn += npages; + } + sg_mark_end(sg); + pt->st.nents = n; + pt->end = pfn; + + return 0; +} + +static const npages_fn_t npages_funcs[] = { + one, + grow, + shrink, + random, + NULL, +}; + +static int igt_sg_alloc(void *ignored) +{ + IGT_TIMEOUT(end_time); + const unsigned long max_order = 20; /* approximating a 4GiB object */ + struct rnd_state prng; + unsigned long prime; + int alloc_error = -ENOMEM; + + for_each_prime_number(prime, max_order) { + unsigned long size = BIT(prime); + int offset; + + for (offset = -1; offset <= 1; offset++) { + unsigned long sz = size + offset; + const npages_fn_t *npages; + struct pfn_table pt; + int err; + + for (npages = npages_funcs; *npages; npages++) { + prandom_seed_state(&prng, + i915_selftest.random_seed); + err = alloc_table(&pt, sz, sz, *npages, &prng, + alloc_error); + if (err == -ENOSPC) + break; + if (err) + return err; + + prandom_seed_state(&prng, + i915_selftest.random_seed); + err = expect_pfn_sgtable(&pt, *npages, &prng, + "sg_alloc_table", + end_time); + sg_free_table(&pt.st); + if (err) + return err; + } + } + + /* Test at least one continuation before accepting oom */ + if (size > SG_MAX_SINGLE_ALLOC) + alloc_error = -ENOSPC; + } + + return 0; +} + +static int igt_sg_trim(void *ignored) +{ + IGT_TIMEOUT(end_time); + const unsigned long max = PAGE_SIZE; /* not prime! */ + struct pfn_table pt; + unsigned long prime; + int alloc_error = -ENOMEM; + + for_each_prime_number(prime, max) { + const npages_fn_t *npages; + int err; + + for (npages = npages_funcs; *npages; npages++) { + struct rnd_state prng; + + prandom_seed_state(&prng, i915_selftest.random_seed); + err = alloc_table(&pt, prime, max, *npages, &prng, + alloc_error); + if (err == -ENOSPC) + break; + if (err) + return err; + + if (i915_sg_trim(&pt.st)) { + if (pt.st.orig_nents != prime || + pt.st.nents != prime) { + pr_err("i915_sg_trim failed (nents %u, orig_nents %u), expected %lu\n", + pt.st.nents, pt.st.orig_nents, prime); + err = -EINVAL; + } else { + prandom_seed_state(&prng, + i915_selftest.random_seed); + err = expect_pfn_sgtable(&pt, + *npages, &prng, + "i915_sg_trim", + end_time); + } + } + sg_free_table(&pt.st); + if (err) + return err; + } + + /* Test at least one continuation before accepting oom */ + if (prime > SG_MAX_SINGLE_ALLOC) + alloc_error = -ENOSPC; + } + + return 0; +} + +int scatterlist_mock_selftests(void) +{ + static const struct i915_subtest tests[] = { + SUBTEST(igt_sg_alloc), + SUBTEST(igt_sg_trim), + }; + + return i915_subtests(tests, NULL); +}