From patchwork Sat Mar 30 17:35:55 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dev Jain X-Patchwork-Id: 784994 Received: from foss.arm.com (foss.arm.com [217.140.110.172]) by smtp.subspace.kernel.org (Postfix) with ESMTP id 70BFE3D0C6; Sat, 30 Mar 2024 17:37:45 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=217.140.110.172 ARC-Seal: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711820268; cv=none; b=ikL6KX/bCwvc9rOobvIGDVLGZ/TgdfaTlls9Z2lPPYXOyiOew0TNok9Us9ihzLbfYHp2Nf0Q+RMC+lQIe0aKVY/IqDVNyqb521edGKy8zdxqrboJ3QJP4NJTB4SDYI9SLej4pg/6Hm8zJ2hNDDx5z/qTNIqIyr158VdfkocUFOE= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1711820268; c=relaxed/simple; bh=86LynxX/Wa5mVbZP8ibHc/96NXH3pPQppzNPOikiI/U=; h=From:To:Cc:Subject:Date:Message-Id:In-Reply-To:References: MIME-Version; b=FWbtpzHBETvvBhxhBWQnrE2gEheYkvLCum9F6oLtZIYolr4S4nngi//ZANlMNY6zP9nmTVPWksUCtDj8EnNPrT0B3kfTV/ePrrXgP3shgrVk8Dz6G+q0bCPUjRxXHnsuFlhRNmhCITjX+VEYeIjqVSXl4WdX2fcgo79I4pG2OiI= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com; spf=pass smtp.mailfrom=arm.com; arc=none smtp.client-ip=217.140.110.172 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=none dis=none) header.from=arm.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=arm.com Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 824DE11FB; Sat, 30 Mar 2024 10:38:12 -0700 (PDT) Received: from e116581.. (unknown [172.31.20.19]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPA id 2C7803F7B4; Sat, 30 Mar 2024 10:37:35 -0700 (PDT) From: Dev Jain To: akpm@linux-foundation.org Cc: shuah@kernel.org, linux-mm@kvack.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org, kaleshsingh@google.com, jhubbard@nvidia.com, Anshuman.Khandual@arm.com, Dev Jain Subject: [PATCH 1/3] selftests/mm: mremap_test: Optimize using pre-filled random array and memcpy Date: Sat, 30 Mar 2024 23:05:55 +0530 Message-Id: <20240330173557.2697684-2-dev.jain@arm.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20240330173557.2697684-1-dev.jain@arm.com> References: <20240330173557.2697684-1-dev.jain@arm.com> Precedence: bulk X-Mailing-List: linux-kselftest@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Allocate a pre-filled random buffer using the seed. Replace iterative copying of the random sequence to buffers using the highly optimized library function memcpy(). Signed-off-by: Dev Jain --- tools/testing/selftests/mm/mremap_test.c | 78 ++++++++++++++++-------- 1 file changed, 53 insertions(+), 25 deletions(-) diff --git a/tools/testing/selftests/mm/mremap_test.c b/tools/testing/selftests/mm/mremap_test.c index 2f8b991f78cb..7fed9cc3911e 100644 --- a/tools/testing/selftests/mm/mremap_test.c +++ b/tools/testing/selftests/mm/mremap_test.c @@ -23,6 +23,7 @@ #define VALIDATION_NO_THRESHOLD 0 /* Verify the entire region */ #define MIN(X, Y) ((X) < (Y) ? (X) : (Y)) +#define MAX(X, Y) ((X) > (Y) ? (X) : (Y)) #define SIZE_MB(m) ((size_t)m * (1024 * 1024)) #define SIZE_KB(k) ((size_t)k * 1024) @@ -296,7 +297,7 @@ static void mremap_expand_merge_offset(FILE *maps_fp, unsigned long page_size) * * |DDDDddddSSSSssss| */ -static void mremap_move_within_range(char pattern_seed) +static void mremap_move_within_range(unsigned int pattern_seed, char *rand_addr) { char *test_name = "mremap mremap move within range"; void *src, *dest; @@ -316,10 +317,7 @@ static void mremap_move_within_range(char pattern_seed) src = (void *)((unsigned long)src & ~(SIZE_MB(2) - 1)); /* Set byte pattern for source block. */ - srand(pattern_seed); - for (i = 0; i < SIZE_MB(2); i++) { - ((char *)src)[i] = (char) rand(); - } + memcpy(src, rand_addr, SIZE_MB(2)); dest = src - SIZE_MB(2); @@ -357,7 +355,7 @@ static void mremap_move_within_range(char pattern_seed) /* Returns the time taken for the remap on success else returns -1. */ static long long remap_region(struct config c, unsigned int threshold_mb, - char pattern_seed) + unsigned int pattern_seed, char *rand_addr) { void *addr, *src_addr, *dest_addr, *dest_preamble_addr; int d; @@ -378,9 +376,7 @@ static long long remap_region(struct config c, unsigned int threshold_mb, } /* Set byte pattern for source block. */ - srand(pattern_seed); - for (t = 0; t < threshold; t++) - memset((char *) src_addr + t, (char) rand(), 1); + memcpy(src_addr, rand_addr, threshold); /* Mask to zero out lower bits of address for alignment */ align_mask = ~(c.dest_alignment - 1); @@ -420,9 +416,7 @@ static long long remap_region(struct config c, unsigned int threshold_mb, } /* Set byte pattern for the dest preamble block. */ - srand(pattern_seed); - for (d = 0; d < c.dest_preamble_size; d++) - memset((char *) dest_preamble_addr + d, (char) rand(), 1); + memcpy(dest_preamble_addr, rand_addr, c.dest_preamble_size); } clock_gettime(CLOCK_MONOTONIC, &t_start); @@ -494,7 +488,8 @@ static long long remap_region(struct config c, unsigned int threshold_mb, * the beginning of the mapping just because the aligned * down address landed on a mapping that maybe does not exist. */ -static void mremap_move_1mb_from_start(char pattern_seed) +static void mremap_move_1mb_from_start(unsigned int pattern_seed, + char *rand_addr) { char *test_name = "mremap move 1mb from start at 1MB+256KB aligned src"; void *src = NULL, *dest = NULL; @@ -520,10 +515,7 @@ static void mremap_move_1mb_from_start(char pattern_seed) } /* Set byte pattern for source block. */ - srand(pattern_seed); - for (i = 0; i < SIZE_MB(2); i++) { - ((char *)src)[i] = (char) rand(); - } + memcpy(src, rand_addr, SIZE_MB(2)); /* * Unmap the beginning of dest so that the aligned address @@ -568,10 +560,10 @@ static void mremap_move_1mb_from_start(char pattern_seed) static void run_mremap_test_case(struct test test_case, int *failures, unsigned int threshold_mb, - unsigned int pattern_seed) + unsigned int pattern_seed, char *rand_addr) { long long remap_time = remap_region(test_case.config, threshold_mb, - pattern_seed); + pattern_seed, rand_addr); if (remap_time < 0) { if (test_case.expect_failure) @@ -642,7 +634,15 @@ int main(int argc, char **argv) int failures = 0; int i, run_perf_tests; unsigned int threshold_mb = VALIDATION_DEFAULT_THRESHOLD; + + /* hard-coded test configs */ + size_t max_test_variable_region_size = _2GB; + size_t max_test_constant_region_size = _2MB; + size_t dest_preamble_size = 10 * _4MB; + unsigned int pattern_seed; + char *rand_addr; + size_t rand_size; int num_expand_tests = 2; int num_misc_tests = 2; struct test test_cases[MAX_TEST] = {}; @@ -659,6 +659,31 @@ int main(int argc, char **argv) ksft_print_msg("Test configs:\n\tthreshold_mb=%u\n\tpattern_seed=%u\n\n", threshold_mb, pattern_seed); + /* + * set preallocated random array according to test configs; see the + * functions for the logic of setting the size + */ + if (!threshold_mb) + rand_size = MAX(max_test_variable_region_size, + max_test_constant_region_size); + else + rand_size = MAX(MIN(threshold_mb * _1MB, + max_test_variable_region_size), + max_test_constant_region_size); + rand_size = MAX(dest_preamble_size, rand_size); + + rand_addr = (char *)mmap(NULL, rand_size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANONYMOUS, -1, 0); + if (rand_addr == MAP_FAILED) { + perror("mmap"); + ksft_exit_fail_msg("cannot mmap rand_addr\n"); + } + + /* fill stream of random bytes */ + srand(pattern_seed); + for (unsigned long i = 0; i < rand_size; ++i) + rand_addr[i] = (char) rand(); + page_size = sysconf(_SC_PAGESIZE); /* Expected mremap failures */ @@ -730,13 +755,13 @@ int main(int argc, char **argv) for (i = 0; i < ARRAY_SIZE(test_cases); i++) run_mremap_test_case(test_cases[i], &failures, threshold_mb, - pattern_seed); + pattern_seed, rand_addr); maps_fp = fopen("/proc/self/maps", "r"); if (maps_fp == NULL) { - ksft_print_msg("Failed to read /proc/self/maps: %s\n", strerror(errno)); - exit(KSFT_FAIL); + munmap(rand_addr, rand_size); + ksft_exit_fail_msg("Failed to read /proc/self/maps: %s\n", strerror(errno)); } mremap_expand_merge(maps_fp, page_size); @@ -744,17 +769,20 @@ int main(int argc, char **argv) fclose(maps_fp); - mremap_move_within_range(pattern_seed); - mremap_move_1mb_from_start(pattern_seed); + mremap_move_within_range(pattern_seed, rand_addr); + mremap_move_1mb_from_start(pattern_seed, rand_addr); if (run_perf_tests) { ksft_print_msg("\n%s\n", "mremap HAVE_MOVE_PMD/PUD optimization time comparison for 1GB region:"); for (i = 0; i < ARRAY_SIZE(perf_test_cases); i++) run_mremap_test_case(perf_test_cases[i], &failures, - threshold_mb, pattern_seed); + threshold_mb, pattern_seed, + rand_addr); } + munmap(rand_addr, rand_size); + if (failures > 0) ksft_exit_fail(); else