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charset="UTF-8" X-Rspam-User: X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 8611040003 X-Stat-Signature: ocxhqooip848pkqnx1hh4iwqrtduf9u1 X-HE-Tag: 1789155718-980722 X-HE-Meta: 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 P1LFbPit 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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 --- 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 0e53eb065a3e..a6026ffd07f1 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -1246,20 +1246,26 @@ 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)) @@ -1278,20 +1284,31 @@ 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) @@ -1342,7 +1359,7 @@ 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); @@ -1395,7 +1412,7 @@ 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; /* @@ -1454,14 +1471,15 @@ 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; } } -- 2.55.0.1007.g17ff1f9808-goog