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Howlett" , Vlastimil Babka , Mike Rapoport , Suren Baghdasaryan , Maarten Lankhorst , Maxime Ripard , Natalie Vock , Tejun Heo , =?utf-8?q?Michal_Koutn=C3=BD?= , Oscar Salvador , Jonathan Corbet , Shuah Khan , Randy Dunlap Cc: Jingxiang Zeng , cgroups@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, dri-devel@lists.freedesktop.org, linux-doc@vger.kernel.org, Jingxiang Zeng X-Mailer: b4 0.13.0 X-Developer-Signature: v=1; a=ed25519-sha256; t=1789721651; l=9424; i=linuszeng@tencent.com; s=20260909; h=from:subject:message-id; bh=CfFjeGPSW+N+Iw1P+GRZXWwVce/M2M1WMHPh1nAZy3E=; b=jHpPy7d+GDh+HUqiPXX7FRb0ibwbrNw7nMVEoGk2aTWH+mJ3cLPntP/bIns5bUIeOcTpATZxL 1OdQfYToxPuBu+9swnmlTRddbMrjgSG3r5RhShXyjuZltZZBazTGJim X-Developer-Key: i=linuszeng@tencent.com; a=ed25519; pk=6K54xRzYIRWqatrAPy86M4E0MsI92BVJBhXwz5NdC74= X-Endpoint-Received: by B4 Relay for linuszeng@tencent.com/20260909 with auth_id=1017 X-Original-From: Jingxiang Zeng Reply-To: linuszeng@tencent.com X-Rspamd-Server: rspam04 X-Rspam-User: X-Stat-Signature: buq9n89dyj4psri4xx96ncrawd9eh66a X-Rspamd-Queue-Id: 2D56210000B X-HE-Tag: 1789721655-789872 X-HE-Meta: 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 4BYz9gFD 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: From: Jingxiang Zeng Move the read/write side of hierarchical protection from struct page_counter to struct page_counter_protection: propagate_protected_usage() updates the protection context of the parent, page_counter_set_min()/low() and page_counter_calculate_protection() operate on it, and memcg and dmem accessors (including dmem_cgroup_below_min()/below_low()) read min/low/emin/elow and children_*_usage from it. struct page_counter keeps its now-unused protection fields for now; they are removed in a follow-up commit. No functional change. Signed-off-by: Jingxiang Zeng --- include/linux/memcontrol.h | 8 +++---- kernel/cgroup/dmem.c | 12 +++++----- mm/memcontrol.c | 8 +++---- mm/page_counter.c | 59 +++++++++++++++++++++++++++++----------------- 4 files changed, 52 insertions(+), 35 deletions(-) diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h index 5936f497aea6..ff69a390a809 100644 --- a/include/linux/memcontrol.h +++ b/include/linux/memcontrol.h @@ -625,8 +625,8 @@ static inline void mem_cgroup_protection(struct mem_cgroup *root, if (root == memcg) return; - *min = READ_ONCE(memcg->memory.emin); - *low = READ_ONCE(memcg->memory.elow); + *min = READ_ONCE(memcg->memory_prot.emin); + *low = READ_ONCE(memcg->memory_prot.elow); } void mem_cgroup_calculate_protection(struct mem_cgroup *root, @@ -650,7 +650,7 @@ static inline bool mem_cgroup_below_low(struct mem_cgroup *target, if (mem_cgroup_unprotected(target, memcg)) return false; - return READ_ONCE(memcg->memory.elow) >= + return READ_ONCE(memcg->memory_prot.elow) >= page_counter_read(&memcg->memory); } @@ -660,7 +660,7 @@ static inline bool mem_cgroup_below_min(struct mem_cgroup *target, if (mem_cgroup_unprotected(target, memcg)) return false; - return READ_ONCE(memcg->memory.emin) >= + return READ_ONCE(memcg->memory_prot.emin) >= page_counter_read(&memcg->memory); } diff --git a/kernel/cgroup/dmem.c b/kernel/cgroup/dmem.c index a4bac0d5ac3b..4027d3d309c8 100644 --- a/kernel/cgroup/dmem.c +++ b/kernel/cgroup/dmem.c @@ -212,12 +212,12 @@ set_resource_max(struct dmem_cgroup_pool_state *pool, u64 val, bool nonblock) static u64 get_resource_low(struct dmem_cgroup_pool_state *pool) { - return pool ? READ_ONCE(pool->cnt.low) : 0; + return pool ? READ_ONCE(pool->cnt.prot->low) : 0; } static u64 get_resource_min(struct dmem_cgroup_pool_state *pool) { - return pool ? READ_ONCE(pool->cnt.min) : 0; + return pool ? READ_ONCE(pool->cnt.prot->min) : 0; } static u64 get_resource_max(struct dmem_cgroup_pool_state *pool) @@ -388,13 +388,13 @@ bool dmem_cgroup_state_evict_valuable(struct dmem_cgroup_pool_state *limit_pool, dmem_cgroup_calculate_protection(limit_pool, test_pool); used = page_counter_read(ctest); - min = READ_ONCE(ctest->emin); + min = READ_ONCE(ctest->prot->emin); if (used <= min) return false; if (!ignore_low) { - low = READ_ONCE(ctest->elow); + low = READ_ONCE(ctest->prot->elow); if (used > low) return true; @@ -787,7 +787,7 @@ bool dmem_cgroup_below_min(struct dmem_cgroup_pool_state *root, * here. */ dmem_cgroup_calculate_protection(root, test); - return page_counter_read(&test->cnt) <= READ_ONCE(test->cnt.emin); + return page_counter_read(&test->cnt) <= READ_ONCE(test->cnt.prot->emin); } EXPORT_SYMBOL_GPL(dmem_cgroup_below_min); @@ -818,7 +818,7 @@ bool dmem_cgroup_below_low(struct dmem_cgroup_pool_state *root, * here. */ dmem_cgroup_calculate_protection(root, test); - return page_counter_read(&test->cnt) <= READ_ONCE(test->cnt.elow); + return page_counter_read(&test->cnt) <= READ_ONCE(test->cnt.prot->elow); } EXPORT_SYMBOL_GPL(dmem_cgroup_below_low); diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 94c538ea3cb5..aaf23e849408 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4860,7 +4860,7 @@ static ssize_t memory_peak_write(struct kernfs_open_file *of, char *buf, static int memory_min_show(struct seq_file *m, void *v) { return seq_puts_memcg_tunable(m, - READ_ONCE(mem_cgroup_from_seq(m)->memory.min)); + READ_ONCE(mem_cgroup_from_seq(m)->memory_prot.min)); } static ssize_t memory_min_write(struct kernfs_open_file *of, @@ -4883,7 +4883,7 @@ static ssize_t memory_min_write(struct kernfs_open_file *of, static int memory_low_show(struct seq_file *m, void *v) { return seq_puts_memcg_tunable(m, - READ_ONCE(mem_cgroup_from_seq(m)->memory.low)); + READ_ONCE(mem_cgroup_from_seq(m)->memory_prot.low)); } static ssize_t memory_low_write(struct kernfs_open_file *of, @@ -6457,6 +6457,6 @@ void mem_cgroup_show_protected_memory(struct mem_cgroup *memcg) memcg = root_mem_cgroup; pr_warn("Memory cgroup min protection %lukB -- low protection %lukB", - K(atomic_long_read(&memcg->memory.children_min_usage)), - K(atomic_long_read(&memcg->memory.children_low_usage))); + K(atomic_long_read(&memcg->memory_prot.children_min_usage)), + K(atomic_long_read(&memcg->memory_prot.children_low_usage))); } diff --git a/mm/page_counter.c b/mm/page_counter.c index aa1f9a9a314f..d33f40ca2c78 100644 --- a/mm/page_counter.c +++ b/mm/page_counter.c @@ -22,28 +22,29 @@ static bool track_protection(struct page_counter *c) static void propagate_protected_usage(struct page_counter *c, unsigned long usage) { + struct page_counter_protection *prot = c->prot; unsigned long protected, old_protected; long delta; - if (!c->parent) + if (!prot || !prot->parent) return; - protected = min(usage, READ_ONCE(c->min)); - old_protected = atomic_long_read(&c->min_usage); + protected = min(usage, READ_ONCE(prot->min)); + old_protected = atomic_long_read(&prot->min_usage); if (protected != old_protected) { - old_protected = atomic_long_xchg(&c->min_usage, protected); + old_protected = atomic_long_xchg(&prot->min_usage, protected); delta = protected - old_protected; if (delta) - atomic_long_add(delta, &c->parent->children_min_usage); + atomic_long_add(delta, &prot->parent->children_min_usage); } - protected = min(usage, READ_ONCE(c->low)); - old_protected = atomic_long_read(&c->low_usage); + protected = min(usage, READ_ONCE(prot->low)); + old_protected = atomic_long_read(&prot->low_usage); if (protected != old_protected) { - old_protected = atomic_long_xchg(&c->low_usage, protected); + old_protected = atomic_long_xchg(&prot->low_usage, protected); delta = protected - old_protected; if (delta) - atomic_long_add(delta, &c->parent->children_low_usage); + atomic_long_add(delta, &prot->parent->children_low_usage); } } @@ -258,7 +259,10 @@ void page_counter_set_min(struct page_counter *counter, unsigned long nr_pages) { struct page_counter *c; - WRITE_ONCE(counter->min, nr_pages); + if (!counter->prot) + return; + + WRITE_ONCE(counter->prot->min, nr_pages); for (c = counter; c; c = c->parent) propagate_protected_usage(c, atomic_long_read(&c->usage)); @@ -275,7 +279,10 @@ void page_counter_set_low(struct page_counter *counter, unsigned long nr_pages) { struct page_counter *c; - WRITE_ONCE(counter->low, nr_pages); + if (!counter->prot) + return; + + WRITE_ONCE(counter->prot->low, nr_pages); for (c = counter; c; c = c->parent) propagate_protected_usage(c, atomic_long_read(&c->usage)); @@ -454,9 +461,18 @@ void page_counter_calculate_protection(struct page_counter *root, struct page_counter *counter, bool recursive_protection) { + struct page_counter_protection *prot = counter->prot; + struct page_counter_protection *parent_prot; unsigned long usage, parent_usage; struct page_counter *parent = counter->parent; + /* + * Only counters with protection support (memory, dmem pools) are + * ever passed here, but guard anyway. + */ + if (!prot) + return; + /* * Effective values of the reclaim targets are ignored so they * can be stale. Have a look at mem_cgroup_protection for more @@ -472,23 +488,24 @@ void page_counter_calculate_protection(struct page_counter *root, return; if (parent == root) { - counter->emin = READ_ONCE(counter->min); - counter->elow = READ_ONCE(counter->low); + prot->emin = READ_ONCE(prot->min); + prot->elow = READ_ONCE(prot->low); return; } + parent_prot = parent->prot; parent_usage = page_counter_read(parent); - WRITE_ONCE(counter->emin, effective_protection(usage, parent_usage, - READ_ONCE(counter->min), - READ_ONCE(parent->emin), - atomic_long_read(&parent->children_min_usage), + WRITE_ONCE(prot->emin, effective_protection(usage, parent_usage, + READ_ONCE(prot->min), + READ_ONCE(parent_prot->emin), + atomic_long_read(&parent_prot->children_min_usage), recursive_protection)); - WRITE_ONCE(counter->elow, effective_protection(usage, parent_usage, - READ_ONCE(counter->low), - READ_ONCE(parent->elow), - atomic_long_read(&parent->children_low_usage), + WRITE_ONCE(prot->elow, effective_protection(usage, parent_usage, + READ_ONCE(prot->low), + READ_ONCE(parent_prot->elow), + atomic_long_read(&parent_prot->children_low_usage), recursive_protection)); } #endif /* CONFIG_MEMCG || CONFIG_CGROUP_DMEM */ -- 2.43.7