On Tue, Jun 23, 2020 at 10:40:35AM -0700, Roman Gushchin wrote: > Instead of having two sets of kmem_caches: one for system-wide and > non-accounted allocations and the second one shared by all accounted > allocations, we can use just one. > > The idea is simple: space for obj_cgroup metadata can be allocated on > demand and filled only for accounted allocations. > > It allows to remove a bunch of code which is required to handle kmem_cache > clones for accounted allocations. There is no more need to create them, > accumulate statistics, propagate attributes, etc. It's a quite > significant simplification. > > Also, because the total number of slab_caches is reduced almost twice (not > all kmem_caches have a memcg clone), some additional memory savings are > expected. On my devvm it additionally saves about 3.5% of slab memory. > > Suggested-by: Johannes Weiner <han...@cmpxchg.org> > Signed-off-by: Roman Gushchin <g...@fb.com> > Reviewed-by: Vlastimil Babka <vba...@suse.cz> > Reviewed-by: Shakeel Butt <shake...@google.com>
This patch results in: {standard input}: Assembler messages: {standard input}:140: Warning: macro instruction expanded into multiple instructions mm/slub.c: In function 'slab_alloc.constprop': mm/slub.c:2897:30: error: inlining failed in call to always_inline 'slab_alloc.constprop': recursive inlining static __always_inline void *slab_alloc(struct kmem_cache *s, and many similar messages when trying to build mips:64r6el_defconfig or mips:defconfig. Bisect log attached. Guenter --- # bad: [aab7ee9f8ff0110bfcd594b33dc33748dc1baf46] Add linux-next specific files for 20200717 # good: [11ba468877bb23f28956a35e896356252d63c983] Linux 5.8-rc5 git bisect start 'HEAD' 'v5.8-rc5' # good: [4d55a7a1298d197755c1a0f4512f56917e938a83] Merge remote-tracking branch 'crypto/master' git bisect good 4d55a7a1298d197755c1a0f4512f56917e938a83 # good: [e63bf5dcce255302e355cb2277a3a39c83752c92] Merge remote-tracking branch 'devicetree/for-next' git bisect good e63bf5dcce255302e355cb2277a3a39c83752c92 # good: [94d932ec3afb923efd8c736974f8316413175a5b] Merge remote-tracking branch 'thunderbolt/next' git bisect good 94d932ec3afb923efd8c736974f8316413175a5b # good: [5ddd2e0dbe8fceb80b0b36bd38a32217be7a04a5] Merge remote-tracking branch 'livepatching/for-next' git bisect good 5ddd2e0dbe8fceb80b0b36bd38a32217be7a04a5 # bad: [40346f79983caf46fb92f779b0353422d43580a9] ipc/shm.c: Remove the superfluous break git bisect bad 40346f79983caf46fb92f779b0353422d43580a9 # bad: [0b917599517f71ddef5f7274a8199a33cecd49b2] kasan: update required compiler versions in documentation git bisect bad 0b917599517f71ddef5f7274a8199a33cecd49b2 # good: [7822c5f77725d5bf4ea48f155b0aa3827db19423] tmpfs: per-superblock i_ino support git bisect good 7822c5f77725d5bf4ea48f155b0aa3827db19423 # bad: [c5b15b89803e3ed2810be285def5f4836e5ee629] mm, memcg: reclaim more aggressively before high allocator throttling git bisect bad c5b15b89803e3ed2810be285def5f4836e5ee629 # good: [2b6d98a0b0cb5ff828228c6a094813c4919727da] mm: memcg/slab: remove redundant check in memcg_accumulate_slabinfo() git bisect good 2b6d98a0b0cb5ff828228c6a094813c4919727da # bad: [d32b702628530c68b4147d410b4cdf21610e9f93] mm: memcg/percpu: per-memcg percpu memory statistics git bisect bad d32b702628530c68b4147d410b4cdf21610e9f93 # bad: [b109396be9be1b8fd91fa4c70bd73a0e93722274] percpu: return number of released bytes from pcpu_free_area() git bisect bad b109396be9be1b8fd91fa4c70bd73a0e93722274 # bad: [6cee58aca5d334ee8195a711e4eb61a05e5f7eb5] kselftests: cgroup: add kernel memory accounting tests git bisect bad 6cee58aca5d334ee8195a711e4eb61a05e5f7eb5 # bad: [2528f5d4f3c139035dc3adcbfb6c63ca14c840f0] mm: memcg/slab: use a single set of kmem_caches for all allocations git bisect bad 2528f5d4f3c139035dc3adcbfb6c63ca14c840f0 # first bad commit: [2528f5d4f3c139035dc3adcbfb6c63ca14c840f0] mm: memcg/slab: use a single set of kmem_caches for all allocations