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| author | Vincent Whitchurch <vincent.whitchurch@axis.com> | 2022-06-20 10:12:50 +0200 |
|---|---|---|
| committer | akpm <akpm@linux-foundation.org> | 2022-07-03 18:08:49 -0700 |
| commit | 30934843019a18df975217e4a819f1c362994764 (patch) | |
| tree | 27cc6e04ea03d44c012cc2f8dced4b2c51ddcb25 /fs/proc | |
| parent | 0506c31d0a8443a9f55eb69d81db426f2eb3296e (diff) | |
| download | lwn-30934843019a18df975217e4a819f1c362994764.tar.gz lwn-30934843019a18df975217e4a819f1c362994764.zip | |
mm/smaps: add Pss_Dirty
Pss is the sum of the sizes of clean and dirty private pages, and the
proportional sizes of clean and dirty shared pages:
Private = Private_Dirty + Private_Clean
Shared_Proportional = Shared_Dirty_Proportional + Shared_Clean_Proportional
Pss = Private + Shared_Proportional
The Shared*Proportional fields are not present in smaps, so it is not
always possible to determine how much of the Pss is from dirty pages and
how much is from clean pages. This information can be useful for
measuring memory usage for the purpose of optimisation, since clean pages
can usually be discarded by the kernel immediately while dirty pages
cannot.
The smaps routines in the kernel already have access to this data, so add
a Pss_Dirty to show it to userspace. Pss_Clean is not added since it can
be calculated from Pss and Pss_Dirty.
Link: https://lkml.kernel.org/r/20220620081251.2928103-1-vincent.whitchurch@axis.com
Signed-off-by: Vincent Whitchurch <vincent.whitchurch@axis.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'fs/proc')
| -rw-r--r-- | fs/proc/task_mmu.c | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/fs/proc/task_mmu.c b/fs/proc/task_mmu.c index 2d04e3470d4c..751c19d5bfdd 100644 --- a/fs/proc/task_mmu.c +++ b/fs/proc/task_mmu.c @@ -406,6 +406,7 @@ struct mem_size_stats { u64 pss_anon; u64 pss_file; u64 pss_shmem; + u64 pss_dirty; u64 pss_locked; u64 swap_pss; }; @@ -427,6 +428,7 @@ static void smaps_page_accumulate(struct mem_size_stats *mss, mss->pss_locked += pss; if (dirty || PageDirty(page)) { + mss->pss_dirty += pss; if (private) mss->private_dirty += size; else @@ -808,6 +810,7 @@ static void __show_smap(struct seq_file *m, const struct mem_size_stats *mss, { SEQ_PUT_DEC("Rss: ", mss->resident); SEQ_PUT_DEC(" kB\nPss: ", mss->pss >> PSS_SHIFT); + SEQ_PUT_DEC(" kB\nPss_Dirty: ", mss->pss_dirty >> PSS_SHIFT); if (rollup_mode) { /* * These are meaningful only for smaps_rollup, otherwise two of |