| Message ID | 20240814062830.26833-5-kanchana.p.sridhar@intel.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | mm: ZSWAP swap-out of mTHP folios | expand |
On Wed, Aug 14, 2024 at 6:28 PM Kanchana P Sridhar <kanchana.p.sridhar@intel.com> wrote: > > Added count_zswap_thp_swpout_vm_event() that will increment the > appropriate mTHP/PMD vmstat event counters if zswap_store succeeds for > a large folio: > > zswap_store mTHP order [0, HPAGE_PMD_ORDER-1] will increment these > vmstat event counters: > > ZSWPOUT_4KB_FOLIO > mTHP_ZSWPOUT_8kB > mTHP_ZSWPOUT_16kB > mTHP_ZSWPOUT_32kB > mTHP_ZSWPOUT_64kB > mTHP_ZSWPOUT_128kB > mTHP_ZSWPOUT_256kB > mTHP_ZSWPOUT_512kB > mTHP_ZSWPOUT_1024kB > > zswap_store of a PMD-size THP, i.e., mTHP order HPAGE_PMD_ORDER, will > increment both these vmstat event counters: > > ZSWPOUT_PMD_THP_FOLIO > mTHP_ZSWPOUT_2048kB > > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> > --- > mm/page_io.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ > 1 file changed, 44 insertions(+) > > diff --git a/mm/page_io.c b/mm/page_io.c > index 0a150c240bf4..ab54d2060cc4 100644 > --- a/mm/page_io.c > +++ b/mm/page_io.c > @@ -172,6 +172,49 @@ int generic_swapfile_activate(struct swap_info_struct *sis, > goto out; > } > > +/* > + * Count vmstats for ZSWAP store of large folios (mTHP and PMD-size THP). > + */ > +static inline void count_zswap_thp_swpout_vm_event(struct folio *folio) > +{ > + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && folio_test_pmd_mappable(folio)) { > + count_vm_event(ZSWPOUT_PMD_THP_FOLIO); > + count_vm_event(mTHP_ZSWPOUT_2048kB); > + } else if (folio_order(folio) == 0) { > + count_vm_event(ZSWPOUT_4KB_FOLIO); > + } else if (IS_ENABLED(CONFIG_THP_SWAP)) { > + switch (folio_order(folio)) { > + case 1: > + count_vm_event(mTHP_ZSWPOUT_8kB); > + break; > + case 2: > + count_vm_event(mTHP_ZSWPOUT_16kB); > + break; > + case 3: > + count_vm_event(mTHP_ZSWPOUT_32kB); > + break; > + case 4: > + count_vm_event(mTHP_ZSWPOUT_64kB); > + break; > + case 5: > + count_vm_event(mTHP_ZSWPOUT_128kB); > + break; > + case 6: > + count_vm_event(mTHP_ZSWPOUT_256kB); > + break; > + case 7: > + count_vm_event(mTHP_ZSWPOUT_512kB); > + break; > + case 8: > + count_vm_event(mTHP_ZSWPOUT_1024kB); > + break; > + case 9: > + count_vm_event(mTHP_ZSWPOUT_2048kB); > + break; > + } The number of orders is PMD_ORDER, also ilog2(MAX_PTRS_PER_PTE) . PMD_ORDER isn't necessarily 9. It seems we need some general way to handle this and avoid so many duplicated case 1, case 2.... case 9. > + } > +} > + > /* > * We may have stale swap cache pages in memory: notice > * them here and get rid of the unnecessary final write. > @@ -196,6 +239,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc) > return ret; > } > if (zswap_store(folio)) { > + count_zswap_thp_swpout_vm_event(folio); > folio_start_writeback(folio); > folio_unlock(folio); > folio_end_writeback(folio); > -- > 2.27.0 > Thanks Barry
Hi Barry, > -----Original Message----- > From: Barry Song <21cnbao@gmail.com> > Sent: Wednesday, August 14, 2024 12:53 AM > To: Sridhar, Kanchana P <kanchana.p.sridhar@intel.com> > Cc: linux-kernel@vger.kernel.org; linux-mm@kvack.org; > hannes@cmpxchg.org; yosryahmed@google.com; nphamcs@gmail.com; > ryan.roberts@arm.com; Huang, Ying <ying.huang@intel.com>; akpm@linux- > foundation.org; Zou, Nanhai <nanhai.zou@intel.com>; Feghali, Wajdi K > <wajdi.k.feghali@intel.com>; Gopal, Vinodh <vinodh.gopal@intel.com> > Subject: Re: [RFC PATCH v1 4/4] mm: page_io: Count successful mTHP zswap > stores in vmstat. > > On Wed, Aug 14, 2024 at 6:28 PM Kanchana P Sridhar > <kanchana.p.sridhar@intel.com> wrote: > > > > Added count_zswap_thp_swpout_vm_event() that will increment the > > appropriate mTHP/PMD vmstat event counters if zswap_store succeeds for > > a large folio: > > > > zswap_store mTHP order [0, HPAGE_PMD_ORDER-1] will increment these > > vmstat event counters: > > > > ZSWPOUT_4KB_FOLIO > > mTHP_ZSWPOUT_8kB > > mTHP_ZSWPOUT_16kB > > mTHP_ZSWPOUT_32kB > > mTHP_ZSWPOUT_64kB > > mTHP_ZSWPOUT_128kB > > mTHP_ZSWPOUT_256kB > > mTHP_ZSWPOUT_512kB > > mTHP_ZSWPOUT_1024kB > > > > zswap_store of a PMD-size THP, i.e., mTHP order HPAGE_PMD_ORDER, will > > increment both these vmstat event counters: > > > > ZSWPOUT_PMD_THP_FOLIO > > mTHP_ZSWPOUT_2048kB > > > > Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> > > --- > > mm/page_io.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ > > 1 file changed, 44 insertions(+) > > > > diff --git a/mm/page_io.c b/mm/page_io.c > > index 0a150c240bf4..ab54d2060cc4 100644 > > --- a/mm/page_io.c > > +++ b/mm/page_io.c > > @@ -172,6 +172,49 @@ int generic_swapfile_activate(struct > swap_info_struct *sis, > > goto out; > > } > > > > +/* > > + * Count vmstats for ZSWAP store of large folios (mTHP and PMD-size THP). > > + */ > > +static inline void count_zswap_thp_swpout_vm_event(struct folio *folio) > > +{ > > + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && > folio_test_pmd_mappable(folio)) { > > + count_vm_event(ZSWPOUT_PMD_THP_FOLIO); > > + count_vm_event(mTHP_ZSWPOUT_2048kB); > > + } else if (folio_order(folio) == 0) { > > + count_vm_event(ZSWPOUT_4KB_FOLIO); > > + } else if (IS_ENABLED(CONFIG_THP_SWAP)) { > > + switch (folio_order(folio)) { > > + case 1: > > + count_vm_event(mTHP_ZSWPOUT_8kB); > > + break; > > + case 2: > > + count_vm_event(mTHP_ZSWPOUT_16kB); > > + break; > > + case 3: > > + count_vm_event(mTHP_ZSWPOUT_32kB); > > + break; > > + case 4: > > + count_vm_event(mTHP_ZSWPOUT_64kB); > > + break; > > + case 5: > > + count_vm_event(mTHP_ZSWPOUT_128kB); > > + break; > > + case 6: > > + count_vm_event(mTHP_ZSWPOUT_256kB); > > + break; > > + case 7: > > + count_vm_event(mTHP_ZSWPOUT_512kB); > > + break; > > + case 8: > > + count_vm_event(mTHP_ZSWPOUT_1024kB); > > + break; > > + case 9: > > + count_vm_event(mTHP_ZSWPOUT_2048kB); > > + break; > > + } > > The number of orders is PMD_ORDER, also ilog2(MAX_PTRS_PER_PTE) . > PMD_ORDER isn't necessarily 9. It seems we need some general way > to handle this and avoid so many duplicated case 1, case 2.... case 9. Thanks for this suggestion. The general way to do this appears to be simply calling count_mthp_stat(folio_order(folio), MTHP_STAT_[Z]SWPOUT) potentially with the addition of a new "MTHP_STAT_ZSWPOUT" to "enum mthp_stat_item". I will make this change in v2 accordingly. Thanks, Kanchana > > > + } > > +} > > + > > /* > > * We may have stale swap cache pages in memory: notice > > * them here and get rid of the unnecessary final write. > > @@ -196,6 +239,7 @@ int swap_writepage(struct page *page, struct > writeback_control *wbc) > > return ret; > > } > > if (zswap_store(folio)) { > > + count_zswap_thp_swpout_vm_event(folio); > > folio_start_writeback(folio); > > folio_unlock(folio); > > folio_end_writeback(folio); > > -- > > 2.27.0 > > > > Thanks > Barry
diff --git a/mm/page_io.c b/mm/page_io.c index 0a150c240bf4..ab54d2060cc4 100644 --- a/mm/page_io.c +++ b/mm/page_io.c @@ -172,6 +172,49 @@ int generic_swapfile_activate(struct swap_info_struct *sis, goto out; } +/* + * Count vmstats for ZSWAP store of large folios (mTHP and PMD-size THP). + */ +static inline void count_zswap_thp_swpout_vm_event(struct folio *folio) +{ + if (IS_ENABLED(CONFIG_TRANSPARENT_HUGEPAGE) && folio_test_pmd_mappable(folio)) { + count_vm_event(ZSWPOUT_PMD_THP_FOLIO); + count_vm_event(mTHP_ZSWPOUT_2048kB); + } else if (folio_order(folio) == 0) { + count_vm_event(ZSWPOUT_4KB_FOLIO); + } else if (IS_ENABLED(CONFIG_THP_SWAP)) { + switch (folio_order(folio)) { + case 1: + count_vm_event(mTHP_ZSWPOUT_8kB); + break; + case 2: + count_vm_event(mTHP_ZSWPOUT_16kB); + break; + case 3: + count_vm_event(mTHP_ZSWPOUT_32kB); + break; + case 4: + count_vm_event(mTHP_ZSWPOUT_64kB); + break; + case 5: + count_vm_event(mTHP_ZSWPOUT_128kB); + break; + case 6: + count_vm_event(mTHP_ZSWPOUT_256kB); + break; + case 7: + count_vm_event(mTHP_ZSWPOUT_512kB); + break; + case 8: + count_vm_event(mTHP_ZSWPOUT_1024kB); + break; + case 9: + count_vm_event(mTHP_ZSWPOUT_2048kB); + break; + } + } +} + /* * We may have stale swap cache pages in memory: notice * them here and get rid of the unnecessary final write. @@ -196,6 +239,7 @@ int swap_writepage(struct page *page, struct writeback_control *wbc) return ret; } if (zswap_store(folio)) { + count_zswap_thp_swpout_vm_event(folio); folio_start_writeback(folio); folio_unlock(folio); folio_end_writeback(folio);
Added count_zswap_thp_swpout_vm_event() that will increment the appropriate mTHP/PMD vmstat event counters if zswap_store succeeds for a large folio: zswap_store mTHP order [0, HPAGE_PMD_ORDER-1] will increment these vmstat event counters: ZSWPOUT_4KB_FOLIO mTHP_ZSWPOUT_8kB mTHP_ZSWPOUT_16kB mTHP_ZSWPOUT_32kB mTHP_ZSWPOUT_64kB mTHP_ZSWPOUT_128kB mTHP_ZSWPOUT_256kB mTHP_ZSWPOUT_512kB mTHP_ZSWPOUT_1024kB zswap_store of a PMD-size THP, i.e., mTHP order HPAGE_PMD_ORDER, will increment both these vmstat event counters: ZSWPOUT_PMD_THP_FOLIO mTHP_ZSWPOUT_2048kB Signed-off-by: Kanchana P Sridhar <kanchana.p.sridhar@intel.com> --- mm/page_io.c | 44 ++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 44 insertions(+)