user/sven/linux.git/include/linux/damon.h, branch v6.1.112

mm/damon/core: make damon_start() waits until kdamond_fn() starts

2024-01-01T12:39:08Z

commit 6376a824595607e99d032a39ba3394988b4fce96 upstream. The cleanup tasks of kdamond threads including reset of corresponding DAMON context's ->kdamond field and decrease of global nr_running_ctxs counter is supposed to be executed by kdamond_fn(). However, commit 0f91d13366a4 ("mm/damon: simplify stop mechanism") made neither damon_start() nor damon_stop() ensure the corresponding kdamond has started the execution of kdamond_fn(). As a result, the cleanup can be skipped if damon_stop() is called fast enough after the previous damon_start(). Especially the skipped reset of ->kdamond could cause a use-after-free. Fix it by waiting for start of kdamond_fn() execution from damon_start(). Link: https://lkml.kernel.org/r/20231208175018.63880-1-sj@kernel.org Fixes: 0f91d13366a4 ("mm/damon: simplify stop mechanism") Signed-off-by: SeongJae Park Reported-by: Jakub Acs Cc: Changbin Du Cc: Jakub Acs Cc: # 5.15.x Signed-off-by: Andrew Morton Signed-off-by: SeongJae Park Signed-off-by: Greg Kroah-Hartman

mm/damon: implement a function for max nr_accesses safe calculation

2023-11-28T17:07:09Z

commit 35f5d94187a6a3a8df2cba54beccca1c2379edb8 upstream. Patch series "avoid divide-by-zero due to max_nr_accesses overflow". The maximum nr_accesses of given DAMON context can be calculated by dividing the aggregation interval by the sampling interval. Some logics in DAMON uses the maximum nr_accesses as a divisor. Hence, the value shouldn't be zero. Such case is avoided since DAMON avoids setting the agregation interval as samller than the sampling interval. However, since nr_accesses is unsigned int while the intervals are unsigned long, the maximum nr_accesses could be zero while casting. Avoid the divide-by-zero by implementing a function that handles the corner case (first patch), and replaces the vulnerable direct max nr_accesses calculations (remaining patches). Note that the patches for the replacements are divided for broken commits, to make backporting on required tres easier. Especially, the last patch is for a patch that not yet merged into the mainline but in mm tree. This patch (of 4): The maximum nr_accesses of given DAMON context can be calculated by dividing the aggregation interval by the sampling interval. Some logics in DAMON uses the maximum nr_accesses as a divisor. Hence, the value shouldn't be zero. Such case is avoided since DAMON avoids setting the agregation interval as samller than the sampling interval. However, since nr_accesses is unsigned int while the intervals are unsigned long, the maximum nr_accesses could be zero while casting. Implement a function that handles the corner case. Note that this commit is not fixing the real issue since this is only introducing the safe function that will replaces the problematic divisions. The replacements will be made by followup commits, to make backporting on stable series easier. Link: https://lkml.kernel.org/r/20231019194924.100347-1-sj@kernel.org Link: https://lkml.kernel.org/r/20231019194924.100347-2-sj@kernel.org Fixes: 198f0f4c58b9 ("mm/damon/vaddr,paddr: support pageout prioritization") Signed-off-by: SeongJae Park Reported-by: Jakub Acs Cc: [5.16+] Signed-off-by: Andrew Morton Signed-off-by: Greg Kroah-Hartman

mm/damon: move sz_damon_region to damon_sz_region

2022-10-13T01:51:49Z

Rename sz_damon_region() to damon_sz_region(), and move it to "include/linux/damon.h", because in many places, we can to use this func. Link: https://lkml.kernel.org/r/20220927001946.85375-1-xhao@linux.alibaba.com Signed-off-by: Xin Hao Suggested-by: SeongJae Park Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon: deduplicate damon_{reclaim,lru_sort}_apply_parameters()

2022-10-03T21:03:31Z

The bodies of damon_{reclaim,lru_sort}_apply_parameters() contain duplicates. This commit adds a common function damon_set_region_biggest_system_ram_default() to remove the duplicates. Link: https://lkml.kernel.org/r/6329f00d.a70a0220.9bb29.3678SMTPIN_ADDED_BROKEN@mx.google.com Signed-off-by: Kaixu Xia Suggested-by: SeongJae Park Reviewed-by: SeongJae Park Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon: return void from damon_set_schemes()

2022-10-03T21:03:27Z

There is no point in returning an int from damon_set_schemes(). It always returns 0 which is meaningless for the caller, so change it to return void directly. Link: https://lkml.kernel.org/r/1663341635-12675-1-git-send-email-kaixuxia@tencent.com Signed-off-by: Kaixu Xia Reviewed-by: SeongJae Park Reviewed-by: Muchun Song Signed-off-by: Andrew Morton

mm/damon: use 'struct damon_target ' instead of 'void ' in target_valid()

2022-10-03T21:03:26Z

We could use 'struct damon_target *' directly instead of 'void *' in target_valid() operation to make code simple. Link: https://lkml.kernel.org/r/1663241621-13293-1-git-send-email-kaixuxia@tencent.com Signed-off-by: Kaixu Xia Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/core: reduce parameters for damon_set_attrs()

2022-10-03T21:03:10Z

Number of parameters for 'damon_set_attrs()' is six. As it could be confusing and verbose, this commit reduces the number by receiving single pointer to a 'struct damon_attrs'. Link: https://lkml.kernel.org/r/20220913174449.50645-7-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon/core: use a dedicated struct for monitoring attributes

2022-10-03T21:03:10Z

DAMON monitoring attributes are directly defined as fields of 'struct damon_ctx'. This makes 'struct damon_ctx' a little long and complicated. This commit defines and uses a struct, 'struct damon_attrs', which is dedicated for only the monitoring attributes to make the purpose of the five values clearer and simplify 'struct damon_ctx'. Link: https://lkml.kernel.org/r/20220913174449.50645-6-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon: remove duplicate get_monitoring_region() definitions

2022-10-03T21:03:08Z

In lru_sort.c and reclaim.c, they are all defining get_monitoring_region() function, there is no need to define it separately. As 'get_monitoring_region()' is not a 'static' function anymore, we try to use a prefix to distinguish with other functions, so there rename it to 'damon_find_biggest_system_ram'. Link: https://lkml.kernel.org/r/20220909213606.136221-1-sj@kernel.org Signed-off-by: Xin Hao Signed-off-by: SeongJae Park Suggested-by: SeongJae Park Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton

mm/damon: introduce struct damos_access_pattern

2022-10-03T21:03:05Z

damon_new_scheme() has too many parameters, so introduce struct damos_access_pattern to simplify it. In additon, we can't use a bpf trace kprobe that has more than 5 parameters. Link: https://lkml.kernel.org/r/20220908191443.129534-1-sj@kernel.org Signed-off-by: Yajun Deng Signed-off-by: SeongJae Park Reviewed-by: SeongJae Park Signed-off-by: Andrew Morton