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charset="UTF-8" X-Stat-Signature: rrsyjw4qqhwzg9h56naxr6fqa33xa43d X-Rspam-User: X-Rspamd-Queue-Id: 9F4A180003 X-Rspamd-Server: rspam03 X-HE-Tag: 1789745610-57577 X-HE-Meta: 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 SWWq6lRk 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 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: List-Subscribe: List-Unsubscribe: smap_gather_stats() interprets its start parameter to mean vma->vm_start when it's set to 0. Eliminate this special interpretation and provide two separate functions for a partial and complete VMA walk. Since smap_gather_stats() operates within a single VMA, we can replace walk_page_vma()/walk_page_range() calls with walk_page_range_vma() which is simpler and also can be called while holding per-VMA lock. No functional change intended. Suggested by: Lorenzo Stoakes Signed-off-by: Suren Baghdasaryan Reviewed-by: Lorenzo Stoakes (ARM) Acked-by: David Hildenbrand (Arm) --- fs/proc/task_mmu.c | 52 +++++++++++++++++++++++++++++++--------------- 1 file changed, 35 insertions(+), 17 deletions(-) diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index f1ce15981253..8f2f302d4563 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1250,20 +1250,26 @@ get_smaps_shmem_walk_ops(struct proc_maps_private *priv) return &smaps_shmem_walk_vma_lock_ops; } -/* - * Gather mem stats from @vma with the indicated beginning - * address @start, and keep them in @mss. +/** + * smap_gather_stats_range() - Gather mem stats from a portion of the @vma. + * @priv: proc maps private state. + * @vma: The VMA to gather stats for. + * @mss: The accumulated stats. + * @start: The address from which to start. * - * Use vm_start of @vma as the beginning address if @start is 0. + * This gathers stats for the portion of the VMA starting at the @start + * address. */ -static void smap_gather_stats(struct proc_maps_private *priv, - struct vm_area_struct *vma, - struct mem_size_stats *mss, unsigned long start) +static void smap_gather_stats_range(struct proc_maps_private *priv, + struct vm_area_struct *vma, + struct mem_size_stats *mss, + unsigned long start) { const struct mm_walk_ops *ops = get_smaps_walk_ops(priv); + const bool is_partial = start > vma->vm_start; /* Invalid start */ - if (start >= vma->vm_end) + if (start < vma->vm_start || start >= vma->vm_end) return; if (vma == get_gate_vma(priv->lock_ctx.mm)) @@ -1282,20 +1288,31 @@ static void smap_gather_stats(struct proc_maps_private *priv, const unsigned long shmem_swapped = shmem_swap_usage(vma); const bool is_cow = vma_is_cow_mapping(vma); - if (start || (shmem_swapped && is_cow)) + if (is_partial || (shmem_swapped && is_cow)) ops = get_smaps_shmem_walk_ops(priv); else mss->swap += shmem_swapped; } - if (!start) - walk_page_vma(vma, ops, mss); - else - walk_page_range(vma->vm_mm, start, vma->vm_end, ops, mss); + walk_page_range_vma(vma, start, vma->vm_end, ops, mss); reacquire_rcu(priv); } +/** + * smap_gather_stats() - Gather mem stats from the entire @vma. + * @priv: proc maps private state. + * @vma: The VMA to gather stats for. + * @mss: The accumulated stats. + * + * This gathers stats for the whole of the VMA. + */ +static void smap_gather_stats(struct proc_maps_private *priv, + struct vm_area_struct *vma, struct mem_size_stats *mss) +{ + smap_gather_stats_range(priv, vma, mss, vma->vm_start); +} + #define SEQ_PUT_DEC(str, val) \ seq_put_decimal_ull_width(m, str, (val) >> 10, 8) @@ -1346,7 +1363,7 @@ static int show_smap(struct seq_file *m, void *v) struct vm_area_struct *vma = v; struct mem_size_stats mss = {}; - smap_gather_stats(priv, vma, &mss, 0); + smap_gather_stats(priv, vma, &mss); show_map_vma(m, vma); @@ -1399,7 +1416,7 @@ static int show_smaps_rollup(struct seq_file *m, void *v) vma_start = vma->vm_start; do { - smap_gather_stats(priv, vma, &mss, 0); + smap_gather_stats(priv, vma, &mss); last_vma_end = vma->vm_end; /* @@ -1458,14 +1475,15 @@ static int show_smaps_rollup(struct seq_file *m, void *v) /* Case 1 and 2 above */ if (vma->vm_start >= last_vma_end) { - smap_gather_stats(priv, vma, &mss, 0); + smap_gather_stats(priv, vma, &mss); last_vma_end = vma->vm_end; continue; } /* Case 4 above */ if (vma->vm_end > last_vma_end) { - smap_gather_stats(priv, vma, &mss, last_vma_end); + smap_gather_stats_range(priv, vma, &mss, + last_vma_end); last_vma_end = vma->vm_end; } } -- 2.55.0.1082.g2b9226bbc0-goog