kernel/linux.git/lib/test_vmalloc.c, branch v6.1.168

treewide: use get_random_{u8,u16}() when possible, part 2

2022-10-11T23:42:58+00:00

Rather than truncate a 32-bit value to a 16-bit value or an 8-bit value, simply use the get_random_{u8,u16}() functions, which are faster than wasting the additional bytes from a 32-bit value. This was done by hand, identifying all of the places where one of the random integer functions was used in a non-32-bit context. Reviewed-by: Greg Kroah-Hartman Reviewed-by: Kees Cook Reviewed-by: Yury Norov Acked-by: Jakub Kicinski Acked-by: Heiko Carstens # for s390 Signed-off-by: Jason A. Donenfeld

treewide: use prandom_u32_max() when possible, part 2

2022-10-11T23:42:58+00:00

Rather than incurring a division or requesting too many random bytes for the given range, use the prandom_u32_max() function, which only takes the minimum required bytes from the RNG and avoids divisions. This was done by hand, covering things that coccinelle could not do on its own. Reviewed-by: Greg Kroah-Hartman Reviewed-by: Kees Cook Reviewed-by: Yury Norov Reviewed-by: Jan Kara # for ext2, ext4, and sbitmap Acked-by: Jakub Kicinski Signed-off-by: Jason A. Donenfeld

lib/test_vmalloc: switch to prandom_u32()

2022-07-04T01:08:42+00:00

A get_random_bytes() function can cause a high contention if it is called across CPUs simultaneously. Because it shares one lock per all CPUs: class name con-bounces contentions waittime-min waittime-max waittime-total waittime-avg acq-bounces acquisitions holdtime-min holdtime-max holdtime-total holdtime-avg &crng->lock: 663145 665886 0.05 8.85 261966.66 0.39 7188152 13731279 0.04 11.89 2181582.30 0.16 ----------- &crng->lock 307835 [<00000000acba59cd>] _extract_crng+0x48/0x90 &crng->lock 358051 [<00000000f0075abc>] _crng_backtrack_protect+0x32/0x90 ----------- &crng->lock 234241 [<00000000f0075abc>] _crng_backtrack_protect+0x32/0x90 &crng->lock 431645 [<00000000acba59cd>] _extract_crng+0x48/0x90 Switch from the get_random_bytes() to prandom_u32() that does not have any internal contention when a random value is needed for the tests. The reason is to minimize CPU cycles introduced by the test-suite itself from the vmalloc performance metrics. Link: https://lkml.kernel.org/r/20220607093449.3100-6-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) Cc: Christoph Hellwig Cc: Matthew Wilcox Cc: Nicholas Piggin Cc: Oleksiy Avramchenko Signed-off-by: Andrew Morton

lib/test_vmalloc.c: use swap() to make code cleaner

2021-11-06T20:30:37+00:00

Use swap() in order to make code cleaner. Issue found by coccinelle. Link: https://lkml.kernel.org/r/20211028111443.15744-1-deng.changcheng@zte.com.cn Signed-off-by: Changcheng Deng Reported-by: Zeal Robot Reviewed-by: Uladzislau Rezki (Sony) Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/test_vmalloc.c: add a new 'nr_pages' parameter

2021-09-03T16:58:14+00:00

In order to simulate different fixed sizes for vmalloc allocation introduce a new parameter that sets number of pages to be allocated for the "fix_size_alloc_test" test. By default 1 page is used unless a different number is specified over the new parameter. Link: https://lkml.kernel.org/r/20210710194151.21370-1-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) Cc: Mel Gorman Cc: Christoph Hellwig Cc: Matthew Wilcox Cc: Nicholas Piggin Cc: Hillf Danton Cc: Michal Hocko Cc: Oleksiy Avramchenko Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/test_vmalloc.c: add a new 'nr_threads' parameter

2021-04-30T18:20:40+00:00

By using this parameter we can specify how many workers are created to perform vmalloc tests. By default it is one CPU. The maximum value is set to 1024. As a result of this change a 'single_cpu_test' one becomes obsolete, therefore it is no longer needed. [urezki@gmail.com: extend max value of nr_threads parameter] Link: https://lkml.kernel.org/r/20210406124536.19658-1-urezki@gmail.com Link: https://lkml.kernel.org/r/20210402202237.20334-2-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) Cc: Hillf Danton Cc: Matthew Wilcox Cc: Michal Hocko Cc: Oleksiy Avramchenko Cc: Shuah Khan Cc: Steven Rostedt Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/test_vmalloc.c: remove two kvfree_rcu() tests

2021-04-30T18:20:40+00:00

Remove two test cases related to kvfree_rcu() and SLAB. Those are considered as redundant now, because similar test functionality has recently been introduced in the "rcuscale" RCU test-suite. Link: https://lkml.kernel.org/r/20210402202237.20334-1-urezki@gmail.com Signed-off-by: Uladzislau Rezki (Sony) Cc: Hillf Danton Cc: Michal Hocko Cc: Matthew Wilcox Cc: Oleksiy Avramchenko Cc: Steven Rostedt Cc: Shuah Khan Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

lib/test_vmalloc.c: Add test cases for kvfree_rcu()

2020-06-29T18:59:26+00:00

Introduce four new test cases for testing the kvfree_rcu() interface. Two of them belong to single argument functionality and another two for 2-argument functionality. The aim is to stress and check how kvfree_rcu() behaves under different load and memory conditions and analyze its performance throughput. Reviewed-by: Joel Fernandes (Google) Signed-off-by: Uladzislau Rezki (Sony) Signed-off-by: Paul E. McKenney

mm: switch the test_vmalloc module to use __vmalloc_node

2020-06-02T17:59:11+00:00

No need to export the very low-level __vmalloc_node_range when the test module can use a slightly higher level variant. [akpm@linux-foundation.org: add missing `node' arg] [akpm@linux-foundation.org: fix riscv nommu build] Signed-off-by: Christoph Hellwig Signed-off-by: Andrew Morton Acked-by: Peter Zijlstra (Intel) Cc: Christian Borntraeger Cc: Christophe Leroy Cc: Daniel Vetter Cc: David Airlie Cc: Gao Xiang Cc: Greg Kroah-Hartman Cc: Haiyang Zhang Cc: Johannes Weiner Cc: "K. Y. Srinivasan" Cc: Laura Abbott Cc: Mark Rutland Cc: Michael Kelley Cc: Minchan Kim Cc: Nitin Gupta Cc: Robin Murphy Cc: Sakari Ailus Cc: Stephen Hemminger Cc: Sumit Semwal Cc: Wei Liu Cc: Benjamin Herrenschmidt Cc: Catalin Marinas Cc: Heiko Carstens Cc: Paul Mackerras Cc: Vasily Gorbik Cc: Will Deacon Link: http://lkml.kernel.org/r/20200414131348.444715-26-hch@lst.de Signed-off-by: Linus Torvalds

lib/test_vmalloc.c:test_func(): eliminate local `ret'

2019-05-15T02:52:49+00:00

Local 'ret' is unneeded and was poorly named: the variable `ret' generally means the "the value which this function will return". Cc: Roman Gushchin Cc: Uladzislau Rezki Cc: Michal Hocko Cc: Matthew Wilcox Cc: Thomas Garnier Cc: Oleksiy Avramchenko Cc: Steven Rostedt Cc: Joel Fernandes Cc: Thomas Gleixner Cc: Ingo Molnar Cc: Tejun Heo Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds