The patch titled Subject: mm: smaps: split PSS into components has been added to the -mm tree. Its filename is mm-smaps-split-pss-into-components.patch This patch should soon appear at http://ozlabs.org/~akpm/mmots/broken-out/mm-smaps-split-pss-into-components.patch and later at http://ozlabs.org/~akpm/mmotm/broken-out/mm-smaps-split-pss-into-components.patch 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 and is updated there every 3-4 working days ------------------------------------------------------ From: Luigi Semenzato <semenzato@xxxxxxxxxxxx> Subject: mm: smaps: split PSS into components Report separate components (anon, file, and shmem) for PSS in smaps_rollup. This helps understand and tune the memory manager behavior in consumer devices, particularly mobile devices. Many of them (e.g. chromebooks and Android-based devices) use zram for anon memory, and perform disk reads for discarded file pages. The difference in latency is large (e.g. reading a single page from SSD is 30 times slower than decompressing a zram page on one popular device), thus it is useful to know how much of the PSS is anon vs. file. This patch also removes a small code duplication in smaps_account, which would have gotten worse otherwise. Also added missing entry for smaps_rollup in Documentation/filesystems/proc.txt. Link: http://lkml.kernel.org/r/20190531154645.39365-1-semenzato@xxxxxxxxxxxx Signed-off-by: Luigi Semenzato <semenzato@xxxxxxxxxxxx> Acked-by: Yu Zhao <yuzhao@xxxxxxxxxxxx> Cc: Sonny Rao <sonnyrao@xxxxxxxxxxxx> Cc: Minchan Kim <minchan@xxxxxxxxxx> Cc: Dmitry Torokhov <dtor@xxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- Documentation/filesystems/proc.txt | 6 + fs/proc/task_mmu.c | 89 ++++++++++++++++++--------- 2 files changed, 64 insertions(+), 31 deletions(-) --- a/Documentation/filesystems/proc.txt~mm-smaps-split-pss-into-components +++ a/Documentation/filesystems/proc.txt @@ -153,9 +153,11 @@ Table 1-1: Process specific entries in / symbol the task is blocked in - or "0" if not blocked. pagemap Page table stack Report full stack trace, enable via CONFIG_STACKTRACE - smaps an extension based on maps, showing the memory consumption of + smaps An extension based on maps, showing the memory consumption of each mapping and flags associated with it - numa_maps an extension based on maps, showing the memory locality and + smaps_rollup Accumulated smaps stats for all mappings of the process. This + can be derived from smaps, but is faster and more convenient + numa_maps An extension based on maps, showing the memory locality and binding policy as well as mem usage (in pages) of each mapping. .............................................................................. --- a/fs/proc/task_mmu.c~mm-smaps-split-pss-into-components +++ a/fs/proc/task_mmu.c @@ -417,17 +417,53 @@ struct mem_size_stats { unsigned long shared_hugetlb; unsigned long private_hugetlb; u64 pss; + u64 pss_anon; + u64 pss_file; + u64 pss_shmem; u64 pss_locked; u64 swap_pss; bool check_shmem_swap; }; +static void smaps_page_accumulate(struct mem_size_stats *mss, + struct page *page, unsigned long size, unsigned long pss, + bool dirty, bool locked, bool private) +{ + mss->pss += pss; + + if (PageAnon(page)) + mss->pss_anon += pss; + else if (PageSwapBacked(page)) + mss->pss_shmem += pss; + else + mss->pss_file += pss; + + if (locked) + mss->pss_locked += pss; + + if (dirty || PageDirty(page)) { + if (private) + mss->private_dirty += size; + else + mss->shared_dirty += size; + } else { + if (private) + mss->private_clean += size; + else + mss->shared_clean += size; + } +} + static void smaps_account(struct mem_size_stats *mss, struct page *page, bool compound, bool young, bool dirty, bool locked) { int i, nr = compound ? 1 << compound_order(page) : 1; unsigned long size = nr * PAGE_SIZE; + /* + * First accumulate quantities that depend only on |size| and the type + * of the compound page. + */ if (PageAnon(page)) { mss->anonymous += size; if (!PageSwapBacked(page) && !dirty && !PageDirty(page)) @@ -440,42 +476,24 @@ static void smaps_account(struct mem_siz mss->referenced += size; /* + * Then accumulate quantities that may depend on sharing, or that may + * differ page-by-page. + * * page_count(page) == 1 guarantees the page is mapped exactly once. * If any subpage of the compound page mapped with PTE it would elevate * page_count(). */ if (page_count(page) == 1) { - if (dirty || PageDirty(page)) - mss->private_dirty += size; - else - mss->private_clean += size; - mss->pss += (u64)size << PSS_SHIFT; - if (locked) - mss->pss_locked += (u64)size << PSS_SHIFT; + smaps_page_accumulate(mss, page, size, size << PSS_SHIFT, dirty, + locked, true); return; } - for (i = 0; i < nr; i++, page++) { int mapcount = page_mapcount(page); - unsigned long pss = (PAGE_SIZE << PSS_SHIFT); + unsigned long pss = PAGE_SIZE << PSS_SHIFT; - if (mapcount >= 2) { - if (dirty || PageDirty(page)) - mss->shared_dirty += PAGE_SIZE; - else - mss->shared_clean += PAGE_SIZE; - mss->pss += pss / mapcount; - if (locked) - mss->pss_locked += pss / mapcount; - } else { - if (dirty || PageDirty(page)) - mss->private_dirty += PAGE_SIZE; - else - mss->private_clean += PAGE_SIZE; - mss->pss += pss; - if (locked) - mss->pss_locked += pss; - } + smaps_page_accumulate(mss, page, PAGE_SIZE, pss / mapcount, + dirty, locked, mapcount < 2); } } @@ -754,10 +772,23 @@ static void smap_gather_stats(struct vm_ seq_put_decimal_ull_width(m, str, (val) >> 10, 8) /* Show the contents common for smaps and smaps_rollup */ -static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss) +static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, + bool rollup_mode) { SEQ_PUT_DEC("Rss: ", mss->resident); SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); + if (rollup_mode) { + /* + * These are meaningful only for smaps_rollup, otherwise two of + * them are zero, and the other one is the same as Pss. + */ + SEQ_PUT_DEC(" kB\nPss_Anon: ", + mss->pss_anon >> PSS_SHIFT); + SEQ_PUT_DEC(" kB\nPss_File: ", + mss->pss_file >> PSS_SHIFT); + SEQ_PUT_DEC(" kB\nPss_Shmem: ", + mss->pss_shmem >> PSS_SHIFT); + } SEQ_PUT_DEC(" kB\nShared_Clean: ", mss->shared_clean); SEQ_PUT_DEC(" kB\nShared_Dirty: ", mss->shared_dirty); SEQ_PUT_DEC(" kB\nPrivate_Clean: ", mss->private_clean); @@ -794,7 +825,7 @@ static int show_smap(struct seq_file *m, SEQ_PUT_DEC(" kB\nMMUPageSize: ", vma_mmu_pagesize(vma)); seq_puts(m, " kB\n"); - __show_smap(m, &mss); + __show_smap(m, &mss, false); seq_printf(m, "THPeligible: %d\n", transparent_hugepage_enabled(vma)); @@ -841,7 +872,7 @@ static int show_smaps_rollup(struct seq_ seq_pad(m, ' '); seq_puts(m, "[rollup]\n"); - __show_smap(m, &mss); + __show_smap(m, &mss, true); release_task_mempolicy(priv); up_read(&mm->mmap_sem); _ Patches currently in -mm which might be from semenzato@xxxxxxxxxxxx are mm-smaps-split-pss-into-components.patch