kernel/drivers/base/node.c, branch linux-5.14.y

Merge tag 'driver-core-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core

2021-07-05T20:51:41Z

Pull driver core changes from Greg KH: "Here is the small set of driver core and debugfs updates for 5.14-rc1. Included in here are: - debugfs api cleanups (touched some drivers) - devres updates - tiny driver core updates and tweaks Nothing major in here at all, and all have been in linux-next for a while with no reported issues" * tag 'driver-core-5.14-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/driver-core: (27 commits) docs: ABI: testing: sysfs-firmware-memmap: add some memmap types. devres: Enable trace events devres: No need to call remove_nodes() when there none present devres: Use list_for_each_safe_from() in remove_nodes() devres: Make locking straight forward in release_nodes() kernfs: move revalidate to be near lookup drivers/base: Constify static attribute_group structs firmware_loader: remove unneeded 'comma' macro devcoredump: remove contact information driver core: Drop helper devm_platform_ioremap_resource_wc() component: Rename 'dev' to 'parent' component: Drop 'dev' argument to component_match_realloc() device property: Don't check for NULL twice in the loops driver core: auxiliary bus: Fix typo in the docs drivers/base/node.c: make CACHE_ATTR define static DEVICE_ATTR_RO debugfs: remove return value of debugfs_create_ulong() debugfs: remove return value of debugfs_create_bool() scsi: snic: debugfs: remove local storage of debugfs files b43: don't save dentries for debugfs b43legacy: don't save dentries for debugfs ...

mm/vmstat: convert NUMA statistics to basic NUMA counters

2021-06-29T17:53:54Z

NUMA statistics are maintained on the zone level for hits, misses, foreign etc but nothing relies on them being perfectly accurate for functional correctness. The counters are used by userspace to get a general overview of a workloads NUMA behaviour but the page allocator incurs a high cost to maintain perfect accuracy similar to what is required for a vmstat like NR_FREE_PAGES. There even is a sysctl vm.numa_stat to allow userspace to turn off the collection of NUMA statistics like NUMA_HIT. This patch converts NUMA_HIT and friends to be NUMA events with similar accuracy to VM events. There is a possibility that slight errors will be introduced but the overall trend as seen by userspace will be similar. The counters are no longer updated from vmstat_refresh context as it is unnecessary overhead for counters that may never be read by userspace. Note that counters could be maintained at the node level to save space but it would have a user-visible impact due to /proc/zoneinfo. [lkp@intel.com: Fix misplaced closing brace for !CONFIG_NUMA] Link: https://lkml.kernel.org/r/20210512095458.30632-4-mgorman@techsingularity.net Signed-off-by: Mel Gorman Acked-by: Vlastimil Babka Acked-by: Peter Zijlstra (Intel) Cc: Chuck Lever Cc: Ingo Molnar Cc: Jesper Dangaard Brouer Cc: Michal Hocko Cc: Sebastian Andrzej Siewior Cc: Thomas Gleixner Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

drivers/base: Constify static attribute_group structs

2021-06-04T13:06:28Z

These are only used by putting their address in an array of pointers to const struct attribute_group (either directly or via the __ATTRIBUTE_GROUP macro). Make them const to allow the compiler to place them in read-only memory. Signed-off-by: Rikard Falkeborn Link: https://lore.kernel.org/r/20210528213408.20067-1-rikard.falkeborn@gmail.com Signed-off-by: Greg Kroah-Hartman

drivers/base/node.c: make CACHE_ATTR define static DEVICE_ATTR_RO

2021-05-21T20:04:58Z

Mark DEVICE_ATTR_RO(name) in CACHE_ATTR(name, fmt)'s definition as static to fix the following Sparse tool reports: drivers/base/node.c:239:1: warning: symbol 'dev_attr_line_size' was not declared. Should it be static? drivers/base/node.c:240:1: warning: symbol 'dev_attr_indexing' was not declared. Should it be static? Where dev_attr_{line_size,indexing} are generated by CACHE_ATTR's expansion. Reported-by: Hulk Robot Signed-off-by: Ruiqi Gong Link: https://lore.kernel.org/r/20210514020548.32483-1-gongruiqi1@huawei.com Signed-off-by: Greg Kroah-Hartman

node: fix device cleanups in error handling code

2021-04-10T09:10:21Z

We can't use kfree() to free device managed resources so the kfree(dev) is against the rules. It's easier to write this code if we open code the device_register() as a device_initialize() and device_add(). That way if dev_set_name() set name fails we can call put_device() and it will clean up correctly. Fixes: acc02a109b04 ("node: Add memory-side caching attributes") Signed-off-by: Dan Carpenter Link: https://lore.kernel.org/r/YHA0JUra+F64+NpB@mwanda Signed-off-by: Greg Kroah-Hartman

mm: memcg: add swapcache stat for memcg v2

2021-02-24T21:38:29Z

This patch adds swapcache stat for the cgroup v2. The swapcache represents the memory that is accounted against both the memory and the swap limit of the cgroup. The main motivation behind exposing the swapcache stat is for enabling users to gracefully migrate from cgroup v1's memsw counter to cgroup v2's memory and swap counters. Cgroup v1's memsw limit allows users to limit the memory+swap usage of a workload but without control on the exact proportion of memory and swap. Cgroup v2 provides separate limits for memory and swap which enables more control on the exact usage of memory and swap individually for the workload. With some little subtleties, the v1's memsw limit can be switched with the sum of the v2's memory and swap limits. However the alternative for memsw usage is not yet available in cgroup v2. Exposing per-cgroup swapcache stat enables that alternative. Adding the memory usage and swap usage and subtracting the swapcache will approximate the memsw usage. This will help in the transparent migration of the workloads depending on memsw usage and limit to v2' memory and swap counters. The reasons these applications are still interested in this approximate memsw usage are: (1) these applications are not really interested in two separate memory and swap usage metrics. A single usage metric is more simple to use and reason about for them. (2) The memsw usage metric hides the underlying system's swap setup from the applications. Applications with multiple instances running in a datacenter with heterogeneous systems (some have swap and some don't) will keep seeing a consistent view of their usage. [akpm@linux-foundation.org: fix CONFIG_SWAP=n build] Link: https://lkml.kernel.org/r/20210108155813.2914586-3-shakeelb@google.com Signed-off-by: Shakeel Butt Acked-by: Michal Hocko Reviewed-by: Roman Gushchin Cc: Johannes Weiner Cc: Muchun Song Cc: Yang Shi Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: memcontrol: convert NR_FILE_PMDMAPPED account to pages

2021-02-24T21:38:29Z

Currently we use struct per_cpu_nodestat to cache the vmstat counters, which leads to inaccurate statistics especially THP vmstat counters. In the systems with hundreds of processors it can be GBs of memory. For example, for a 96 CPUs system, the threshold is the maximum number of 125. And the per cpu counters can cache 23.4375 GB in total. The THP page is already a form of batched addition (it will add 512 worth of memory in one go) so skipping the batching seems like sensible. Although every THP stats update overflows the per-cpu counter, resorting to atomic global updates. But it can make the statistics more accuracy for the THP vmstat counters. So we convert the NR_FILE_PMDMAPPED account to pages. This patch is consistent with 8f182270dfec ("mm/swap.c: flush lru pvecs on compound page arrival"). Doing this also can make the unit of vmstat counters more unified. Finally, the unit of the vmstat counters are pages, kB and bytes. The B/KB suffix can tell us that the unit is bytes or kB. The rest which is without suffix are pages. Link: https://lkml.kernel.org/r/20201228164110.2838-7-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alexey Dobriyan Cc: Feng Tang Cc: Greg Kroah-Hartman Cc: Hugh Dickins Cc: Johannes Weiner Cc: Joonsoo Kim Cc: Michal Hocko Cc: NeilBrown Cc: Pankaj Gupta Cc: Rafael. J. Wysocki Cc: Randy Dunlap Cc: Roman Gushchin Cc: Sami Tolvanen Cc: Shakeel Butt Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: memcontrol: convert NR_SHMEM_PMDMAPPED account to pages

2021-02-24T21:38:29Z

Currently we use struct per_cpu_nodestat to cache the vmstat counters, which leads to inaccurate statistics especially THP vmstat counters. In the systems with hundreds of processors it can be GBs of memory. For example, for a 96 CPUs system, the threshold is the maximum number of 125. And the per cpu counters can cache 23.4375 GB in total. The THP page is already a form of batched addition (it will add 512 worth of memory in one go) so skipping the batching seems like sensible. Although every THP stats update overflows the per-cpu counter, resorting to atomic global updates. But it can make the statistics more accuracy for the THP vmstat counters. So we convert the NR_SHMEM_PMDMAPPED account to pages. This patch is consistent with 8f182270dfec ("mm/swap.c: flush lru pvecs on compound page arrival"). Doing this also can make the unit of vmstat counters more unified. Finally, the unit of the vmstat counters are pages, kB and bytes. The B/KB suffix can tell us that the unit is bytes or kB. The rest which is without suffix are pages. Link: https://lkml.kernel.org/r/20201228164110.2838-6-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alexey Dobriyan Cc: Feng Tang Cc: Greg Kroah-Hartman Cc: Hugh Dickins Cc: Johannes Weiner Cc: Joonsoo Kim Cc: Michal Hocko Cc: NeilBrown Cc: Pankaj Gupta Cc: Rafael. J. Wysocki Cc: Randy Dunlap Cc: Roman Gushchin Cc: Sami Tolvanen Cc: Shakeel Butt Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: memcontrol: convert NR_SHMEM_THPS account to pages

2021-02-24T21:38:29Z

Currently we use struct per_cpu_nodestat to cache the vmstat counters, which leads to inaccurate statistics especially THP vmstat counters. In the systems with hundreds of processors it can be GBs of memory. For example, for a 96 CPUs system, the threshold is the maximum number of 125. And the per cpu counters can cache 23.4375 GB in total. The THP page is already a form of batched addition (it will add 512 worth of memory in one go) so skipping the batching seems like sensible. Although every THP stats update overflows the per-cpu counter, resorting to atomic global updates. But it can make the statistics more accuracy for the THP vmstat counters. So we convert the NR_SHMEM_THPS account to pages. This patch is consistent with 8f182270dfec ("mm/swap.c: flush lru pvecs on compound page arrival"). Doing this also can make the unit of vmstat counters more unified. Finally, the unit of the vmstat counters are pages, kB and bytes. The B/KB suffix can tell us that the unit is bytes or kB. The rest which is without suffix are pages. Link: https://lkml.kernel.org/r/20201228164110.2838-5-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alexey Dobriyan Cc: Feng Tang Cc: Greg Kroah-Hartman Cc: Hugh Dickins Cc: Johannes Weiner Cc: Joonsoo Kim Cc: Michal Hocko Cc: NeilBrown Cc: Pankaj Gupta Cc: Rafael. J. Wysocki Cc: Randy Dunlap Cc: Roman Gushchin Cc: Sami Tolvanen Cc: Shakeel Butt Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds

mm: memcontrol: convert NR_FILE_THPS account to pages

2021-02-24T21:38:29Z

Currently we use struct per_cpu_nodestat to cache the vmstat counters, which leads to inaccurate statistics especially THP vmstat counters. In the systems with if hundreds of processors it can be GBs of memory. For example, for a 96 CPUs system, the threshold is the maximum number of 125. And the per cpu counters can cache 23.4375 GB in total. The THP page is already a form of batched addition (it will add 512 worth of memory in one go) so skipping the batching seems like sensible. Although every THP stats update overflows the per-cpu counter, resorting to atomic global updates. But it can make the statistics more accuracy for the THP vmstat counters. So we convert the NR_FILE_THPS account to pages. This patch is consistent with 8f182270dfec ("mm/swap.c: flush lru pvecs on compound page arrival"). Doing this also can make the unit of vmstat counters more unified. Finally, the unit of the vmstat counters are pages, kB and bytes. The B/KB suffix can tell us that the unit is bytes or kB. The rest which is without suffix are pages. Link: https://lkml.kernel.org/r/20201228164110.2838-4-songmuchun@bytedance.com Signed-off-by: Muchun Song Cc: Alexey Dobriyan Cc: Feng Tang Cc: Greg Kroah-Hartman Cc: Hugh Dickins Cc: Johannes Weiner Cc: Joonsoo Kim Cc: Michal Hocko Cc: NeilBrown Cc: Pankaj Gupta Cc: Rafael. J. Wysocki Cc: Randy Dunlap Cc: Roman Gushchin Cc: Sami Tolvanen Cc: Shakeel Butt Cc: Vladimir Davydov Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds