The patch titled Subject: mempolicy trivia: slightly more consistent naming has been added to the -mm mm-unstable branch. Its filename is mempolicy-trivia-slightly-more-consistent-naming.patch This patch will shortly appear at https://git.kernel.org/pub/scm/linux/kernel/git/akpm/25-new.git/tree/patches/mempolicy-trivia-slightly-more-consistent-naming.patch This patch will later appear in the mm-unstable branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/process/submit-checklist.rst when testing your code *** The -mm tree is included into linux-next via the mm-everything branch at git://git.kernel.org/pub/scm/linux/kernel/git/akpm/mm and is updated there every 2-3 working days ------------------------------------------------------ From: Hugh Dickins <hughd@xxxxxxxxxx> Subject: mempolicy trivia: slightly more consistent naming Date: Tue, 3 Oct 2023 02:20:14 -0700 (PDT) Before getting down to work, do a little cleanup, mainly of inconsistent variable naming. I gave up trying to rationalize mpol versus pol versus policy, and node versus nid, but let's avoid p and nd. Remove a few superfluous blank lines, but add one; and here prefer vma->vm_policy to vma_policy(vma) - the latter being appropriate in other sources, which have to allow for !CONFIG_NUMA. That intriguing line about KERNEL_DS? should have gone in v2.6.15, when numa_policy_init() stopped using set_mempolicy(2)'s system call handler. Link: https://lkml.kernel.org/r/68287974-b6ae-7df-4ba-d19ddd69cbf@xxxxxxxxxx Signed-off-by: Hugh Dickins <hughd@xxxxxxxxxx> Reviewed-by: Matthew Wilcox (Oracle) <willy@xxxxxxxxxxxxx> Cc: Andi Kleen <ak@xxxxxxxxxxxxxxx> Cc: Christoph Lameter <cl@xxxxxxxxx> Cc: David Hildenbrand <david@xxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: "Huang, Ying" <ying.huang@xxxxxxxxx> Cc: Kefeng Wang <wangkefeng.wang@xxxxxxxxxx> Cc: Mel Gorman <mgorman@xxxxxxxxxxxxxxxxxxx> Cc: Michal Hocko <mhocko@xxxxxxxx> Cc: Mike Kravetz <mike.kravetz@xxxxxxxxxx> Cc: Nhat Pham <nphamcs@xxxxxxxxx> Cc: Sidhartha Kumar <sidhartha.kumar@xxxxxxxxxx> Cc: Suren Baghdasaryan <surenb@xxxxxxxxxx> Cc: Tejun heo <tj@xxxxxxxxxx> Cc: Vishal Moola (Oracle) <vishal.moola@xxxxxxxxx> Cc: Yang Shi <shy828301@xxxxxxxxx> Cc: Yosry Ahmed <yosryahmed@xxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/mempolicy.h | 11 ++--- mm/mempolicy.c | 73 ++++++++++++++++-------------------- 2 files changed, 38 insertions(+), 46 deletions(-) --- a/include/linux/mempolicy.h~mempolicy-trivia-slightly-more-consistent-naming +++ a/include/linux/mempolicy.h @@ -124,10 +124,9 @@ struct shared_policy { int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst); void mpol_shared_policy_init(struct shared_policy *sp, struct mempolicy *mpol); -int mpol_set_shared_policy(struct shared_policy *info, - struct vm_area_struct *vma, - struct mempolicy *new); -void mpol_free_shared_policy(struct shared_policy *p); +int mpol_set_shared_policy(struct shared_policy *sp, + struct vm_area_struct *vma, struct mempolicy *mpol); +void mpol_free_shared_policy(struct shared_policy *sp); struct mempolicy *mpol_shared_policy_lookup(struct shared_policy *sp, unsigned long idx); @@ -191,7 +190,7 @@ static inline bool mpol_equal(struct mem return true; } -static inline void mpol_put(struct mempolicy *p) +static inline void mpol_put(struct mempolicy *pol) { } @@ -210,7 +209,7 @@ static inline void mpol_shared_policy_in { } -static inline void mpol_free_shared_policy(struct shared_policy *p) +static inline void mpol_free_shared_policy(struct shared_policy *sp) { } --- a/mm/mempolicy.c~mempolicy-trivia-slightly-more-consistent-naming +++ a/mm/mempolicy.c @@ -25,7 +25,7 @@ * to the last. It would be better if bind would truly restrict * the allocation to memory nodes instead * - * preferred Try a specific node first before normal fallback. + * preferred Try a specific node first before normal fallback. * As a special case NUMA_NO_NODE here means do the allocation * on the local CPU. This is normally identical to default, * but useful to set in a VMA when you have a non default @@ -52,7 +52,7 @@ * on systems with highmem kernel lowmem allocation don't get policied. * Same with GFP_DMA allocations. * - * For shmfs/tmpfs/hugetlbfs shared memory the policy is shared between + * For shmem/tmpfs shared memory the policy is shared between * all users and remembered even when nobody has memory mapped. */ @@ -291,6 +291,7 @@ static struct mempolicy *mpol_new(unsign return ERR_PTR(-EINVAL); } else if (nodes_empty(*nodes)) return ERR_PTR(-EINVAL); + policy = kmem_cache_alloc(policy_cache, GFP_KERNEL); if (!policy) return ERR_PTR(-ENOMEM); @@ -303,11 +304,11 @@ static struct mempolicy *mpol_new(unsign } /* Slow path of a mpol destructor. */ -void __mpol_put(struct mempolicy *p) +void __mpol_put(struct mempolicy *pol) { - if (!atomic_dec_and_test(&p->refcnt)) + if (!atomic_dec_and_test(&pol->refcnt)) return; - kmem_cache_free(policy_cache, p); + kmem_cache_free(policy_cache, pol); } static void mpol_rebind_default(struct mempolicy *pol, const nodemask_t *nodes) @@ -364,7 +365,6 @@ static void mpol_rebind_policy(struct me * * Called with task's alloc_lock held. */ - void mpol_rebind_task(struct task_struct *tsk, const nodemask_t *new) { mpol_rebind_policy(tsk->mempolicy, new); @@ -375,7 +375,6 @@ void mpol_rebind_task(struct task_struct * * Call holding a reference to mm. Takes mm->mmap_lock during call. */ - void mpol_rebind_mm(struct mm_struct *mm, nodemask_t *new) { struct vm_area_struct *vma; @@ -757,7 +756,7 @@ queue_pages_range(struct mm_struct *mm, * This must be called with the mmap_lock held for writing. */ static int vma_replace_policy(struct vm_area_struct *vma, - struct mempolicy *pol) + struct mempolicy *pol) { int err; struct mempolicy *old; @@ -800,7 +799,7 @@ static int mbind_range(struct vma_iterat vmstart = vma->vm_start; } - if (mpol_equal(vma_policy(vma), new_pol)) { + if (mpol_equal(vma->vm_policy, new_pol)) { *prev = vma; return 0; } @@ -855,18 +854,18 @@ out: * * Called with task's alloc_lock held */ -static void get_policy_nodemask(struct mempolicy *p, nodemask_t *nodes) +static void get_policy_nodemask(struct mempolicy *pol, nodemask_t *nodes) { nodes_clear(*nodes); - if (p == &default_policy) + if (pol == &default_policy) return; - switch (p->mode) { + switch (pol->mode) { case MPOL_BIND: case MPOL_INTERLEAVE: case MPOL_PREFERRED: case MPOL_PREFERRED_MANY: - *nodes = p->nodes; + *nodes = pol->nodes; break; case MPOL_LOCAL: /* return empty node mask for local allocation */ @@ -1634,7 +1633,6 @@ out: out_put: put_task_struct(task); goto out; - } SYSCALL_DEFINE4(migrate_pages, pid_t, pid, unsigned long, maxnode, @@ -1644,7 +1642,6 @@ SYSCALL_DEFINE4(migrate_pages, pid_t, pi return kernel_migrate_pages(pid, maxnode, old_nodes, new_nodes); } - /* Retrieve NUMA policy */ static int kernel_get_mempolicy(int __user *policy, unsigned long __user *nmask, @@ -1827,10 +1824,10 @@ nodemask_t *policy_nodemask(gfp_t gfp, s * policy_node() is always coupled with policy_nodemask(), which * secures the nodemask limit for 'bind' and 'prefer-many' policy. */ -static int policy_node(gfp_t gfp, struct mempolicy *policy, int nd) +static int policy_node(gfp_t gfp, struct mempolicy *policy, int nid) { if (policy->mode == MPOL_PREFERRED) { - nd = first_node(policy->nodes); + nid = first_node(policy->nodes); } else { /* * __GFP_THISNODE shouldn't even be used with the bind policy @@ -1845,19 +1842,18 @@ static int policy_node(gfp_t gfp, struct policy->home_node != NUMA_NO_NODE) return policy->home_node; - return nd; + return nid; } /* Do dynamic interleaving for a process */ -static unsigned interleave_nodes(struct mempolicy *policy) +static unsigned int interleave_nodes(struct mempolicy *policy) { - unsigned next; - struct task_struct *me = current; + unsigned int nid; - next = next_node_in(me->il_prev, policy->nodes); - if (next < MAX_NUMNODES) - me->il_prev = next; - return next; + nid = next_node_in(current->il_prev, policy->nodes); + if (nid < MAX_NUMNODES) + current->il_prev = nid; + return nid; } /* @@ -2347,7 +2343,7 @@ unsigned long alloc_pages_bulk_array_mem int vma_dup_policy(struct vm_area_struct *src, struct vm_area_struct *dst) { - struct mempolicy *pol = mpol_dup(vma_policy(src)); + struct mempolicy *pol = mpol_dup(src->vm_policy); if (IS_ERR(pol)) return PTR_ERR(pol); @@ -2771,40 +2767,40 @@ put_mpol: } } -int mpol_set_shared_policy(struct shared_policy *info, - struct vm_area_struct *vma, struct mempolicy *npol) +int mpol_set_shared_policy(struct shared_policy *sp, + struct vm_area_struct *vma, struct mempolicy *pol) { int err; struct sp_node *new = NULL; unsigned long sz = vma_pages(vma); - if (npol) { - new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, npol); + if (pol) { + new = sp_alloc(vma->vm_pgoff, vma->vm_pgoff + sz, pol); if (!new) return -ENOMEM; } - err = shared_policy_replace(info, vma->vm_pgoff, vma->vm_pgoff+sz, new); + err = shared_policy_replace(sp, vma->vm_pgoff, vma->vm_pgoff + sz, new); if (err && new) sp_free(new); return err; } /* Free a backing policy store on inode delete. */ -void mpol_free_shared_policy(struct shared_policy *p) +void mpol_free_shared_policy(struct shared_policy *sp) { struct sp_node *n; struct rb_node *next; - if (!p->root.rb_node) + if (!sp->root.rb_node) return; - write_lock(&p->lock); - next = rb_first(&p->root); + write_lock(&sp->lock); + next = rb_first(&sp->root); while (next) { n = rb_entry(next, struct sp_node, nd); next = rb_next(&n->nd); - sp_delete(p, n); + sp_delete(sp, n); } - write_unlock(&p->lock); + write_unlock(&sp->lock); } #ifdef CONFIG_NUMA_BALANCING @@ -2854,7 +2850,6 @@ static inline void __init check_numabala } #endif /* CONFIG_NUMA_BALANCING */ -/* assumes fs == KERNEL_DS */ void __init numa_policy_init(void) { nodemask_t interleave_nodes; @@ -2917,7 +2912,6 @@ void numa_default_policy(void) /* * Parse and format mempolicy from/to strings */ - static const char * const policy_modes[] = { [MPOL_DEFAULT] = "default", @@ -2928,7 +2922,6 @@ static const char * const policy_modes[] [MPOL_PREFERRED_MANY] = "prefer (many)", }; - #ifdef CONFIG_TMPFS /** * mpol_parse_str - parse string to mempolicy, for tmpfs mpol mount option. _ Patches currently in -mm which might be from hughd@xxxxxxxxxx are hugetlbfs-drop-shared-numa-mempolicy-pretence.patch kernfs-drop-shared-numa-mempolicy-hooks.patch mempolicy-fix-migrate_pages2-syscall-return-nr_failed.patch mempolicy-trivia-delete-those-ancient-pr_debugs.patch mempolicy-trivia-slightly-more-consistent-naming.patch mempolicy-trivia-use-pgoff_t-in-shared-mempolicy-tree.patch mempolicy-mpol_shared_policy_init-without-pseudo-vma.patch mempolicy-remove-confusing-mpol_mf_lazy-dead-code.patch mm-add-page_rmappable_folio-wrapper.patch mempolicy-alloc_pages_mpol-for-numa-policy-without-vma.patch mempolicy-mmap_lock-is-not-needed-while-migrating-folios.patch mempolicy-migration-attempt-to-match-interleave-nodes.patch