From: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Since zswap now writes back pages from memcg-specific LRUs, we now need a
new stat to show writebacks count for each memcg.
Suggested-by: Nhat Pham <nphamcs@gmail.com>
Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
Signed-off-by: Nhat Pham <nphamcs@gmail.com>
---
include/linux/memcontrol.h | 2 ++
mm/memcontrol.c | 15 +++++++++++++++
mm/zswap.c | 3 +++
3 files changed, 20 insertions(+)
diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
index 3de10fabea0f..7868b1e00bf5 100644
--- a/include/linux/memcontrol.h
+++ b/include/linux/memcontrol.h
@@ -38,6 +38,7 @@ enum memcg_stat_item {
MEMCG_KMEM,
MEMCG_ZSWAP_B,
MEMCG_ZSWAPPED,
+ MEMCG_ZSWAP_WB,
MEMCG_NR_STAT,
};
@@ -1884,6 +1885,7 @@ static inline void count_objcg_event(struct obj_cgroup *objcg,
bool obj_cgroup_may_zswap(struct obj_cgroup *objcg);
void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size);
void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size);
+void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg);
#else
static inline bool obj_cgroup_may_zswap(struct obj_cgroup *objcg)
{
diff --git a/mm/memcontrol.c b/mm/memcontrol.c
index 1bde67b29287..a9118871e5a6 100644
--- a/mm/memcontrol.c
+++ b/mm/memcontrol.c
@@ -1505,6 +1505,7 @@ static const struct memory_stat memory_stats[] = {
#if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
{ "zswap", MEMCG_ZSWAP_B },
{ "zswapped", MEMCG_ZSWAPPED },
+ { "zswap_wb", MEMCG_ZSWAP_WB },
#endif
{ "file_mapped", NR_FILE_MAPPED },
{ "file_dirty", NR_FILE_DIRTY },
@@ -1541,6 +1542,7 @@ static int memcg_page_state_unit(int item)
switch (item) {
case MEMCG_PERCPU_B:
case MEMCG_ZSWAP_B:
+ case MEMCG_ZSWAP_WB:
case NR_SLAB_RECLAIMABLE_B:
case NR_SLAB_UNRECLAIMABLE_B:
case WORKINGSET_REFAULT_ANON:
@@ -7861,6 +7863,19 @@ void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size)
rcu_read_unlock();
}
+void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg)
+{
+ struct mem_cgroup *memcg;
+
+ if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
+ return;
+
+ rcu_read_lock();
+ memcg = obj_cgroup_memcg(objcg);
+ mod_memcg_state(memcg, MEMCG_ZSWAP_WB, 1);
+ rcu_read_unlock();
+}
+
static u64 zswap_current_read(struct cgroup_subsys_state *css,
struct cftype *cft)
{
diff --git a/mm/zswap.c b/mm/zswap.c
index d2989ad11814..15485427e3fa 100644
--- a/mm/zswap.c
+++ b/mm/zswap.c
@@ -704,6 +704,9 @@ static enum lru_status shrink_memcg_cb(struct list_head *item, struct list_lru_o
}
zswap_written_back_pages++;
+ if (entry->objcg)
+ obj_cgroup_report_zswap_wb(entry->objcg);
+
/*
* Writeback started successfully, the page now belongs to the
* swapcache. Drop the entry from zswap - unless invalidate already
--
2.34.1On Tue, Oct 17, 2023 at 4:21 PM Nhat Pham <nphamcs@gmail.com> wrote:
>
> From: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
>
> Since zswap now writes back pages from memcg-specific LRUs, we now need a
> new stat to show writebacks count for each memcg.
>
> Suggested-by: Nhat Pham <nphamcs@gmail.com>
> Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
> Signed-off-by: Nhat Pham <nphamcs@gmail.com>
> ---
> include/linux/memcontrol.h | 2 ++
> mm/memcontrol.c | 15 +++++++++++++++
> mm/zswap.c | 3 +++
> 3 files changed, 20 insertions(+)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 3de10fabea0f..7868b1e00bf5 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -38,6 +38,7 @@ enum memcg_stat_item {
> MEMCG_KMEM,
> MEMCG_ZSWAP_B,
> MEMCG_ZSWAPPED,
> + MEMCG_ZSWAP_WB,
> MEMCG_NR_STAT,
> };
>
> @@ -1884,6 +1885,7 @@ static inline void count_objcg_event(struct obj_cgroup *objcg,
> bool obj_cgroup_may_zswap(struct obj_cgroup *objcg);
> void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size);
> void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size);
> +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg);
> #else
> static inline bool obj_cgroup_may_zswap(struct obj_cgroup *objcg)
> {
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 1bde67b29287..a9118871e5a6 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -1505,6 +1505,7 @@ static const struct memory_stat memory_stats[] = {
> #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
> { "zswap", MEMCG_ZSWAP_B },
> { "zswapped", MEMCG_ZSWAPPED },
> + { "zswap_wb", MEMCG_ZSWAP_WB },
zswap_writeback would be more consistent with file_writeback below.
Taking a step back, this is not really a "state". We increment it by 1
every time and never decrement it. Sounds awfully similar to events :)
You can also use count_objcg_event() directly and avoid the need for
obj_cgroup_report_zswap_wb() below.
> #endif
> { "file_mapped", NR_FILE_MAPPED },
> { "file_dirty", NR_FILE_DIRTY },
> @@ -1541,6 +1542,7 @@ static int memcg_page_state_unit(int item)
> switch (item) {
> case MEMCG_PERCPU_B:
> case MEMCG_ZSWAP_B:
> + case MEMCG_ZSWAP_WB:
> case NR_SLAB_RECLAIMABLE_B:
> case NR_SLAB_UNRECLAIMABLE_B:
> case WORKINGSET_REFAULT_ANON:
> @@ -7861,6 +7863,19 @@ void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size)
> rcu_read_unlock();
> }
>
> +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg)
> +{
> + struct mem_cgroup *memcg;
> +
> + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
> + return;
> +
> + rcu_read_lock();
> + memcg = obj_cgroup_memcg(objcg);
> + mod_memcg_state(memcg, MEMCG_ZSWAP_WB, 1);
> + rcu_read_unlock();
> +}
> +
> static u64 zswap_current_read(struct cgroup_subsys_state *css,
> struct cftype *cft)
> {
> diff --git a/mm/zswap.c b/mm/zswap.c
> index d2989ad11814..15485427e3fa 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -704,6 +704,9 @@ static enum lru_status shrink_memcg_cb(struct list_head *item, struct list_lru_o
> }
> zswap_written_back_pages++;
>
> + if (entry->objcg)
> + obj_cgroup_report_zswap_wb(entry->objcg);
> +
> /*
> * Writeback started successfully, the page now belongs to the
> * swapcache. Drop the entry from zswap - unless invalidate already
> --
> 2.34.1
On Wed, Oct 18, 2023 at 4:25 PM Yosry Ahmed <yosryahmed@google.com> wrote:
>
> On Tue, Oct 17, 2023 at 4:21 PM Nhat Pham <nphamcs@gmail.com> wrote:
> >
> > From: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
> >
> > Since zswap now writes back pages from memcg-specific LRUs, we now need a
> > new stat to show writebacks count for each memcg.
> >
> > Suggested-by: Nhat Pham <nphamcs@gmail.com>
> > Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
> > Signed-off-by: Nhat Pham <nphamcs@gmail.com>
> > ---
> > include/linux/memcontrol.h | 2 ++
> > mm/memcontrol.c | 15 +++++++++++++++
> > mm/zswap.c | 3 +++
> > 3 files changed, 20 insertions(+)
> >
> > diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> > index 3de10fabea0f..7868b1e00bf5 100644
> > --- a/include/linux/memcontrol.h
> > +++ b/include/linux/memcontrol.h
> > @@ -38,6 +38,7 @@ enum memcg_stat_item {
> > MEMCG_KMEM,
> > MEMCG_ZSWAP_B,
> > MEMCG_ZSWAPPED,
> > + MEMCG_ZSWAP_WB,
> > MEMCG_NR_STAT,
> > };
> >
> > @@ -1884,6 +1885,7 @@ static inline void count_objcg_event(struct obj_cgroup *objcg,
> > bool obj_cgroup_may_zswap(struct obj_cgroup *objcg);
> > void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size);
> > void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size);
> > +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg);
> > #else
> > static inline bool obj_cgroup_may_zswap(struct obj_cgroup *objcg)
> > {
> > diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> > index 1bde67b29287..a9118871e5a6 100644
> > --- a/mm/memcontrol.c
> > +++ b/mm/memcontrol.c
> > @@ -1505,6 +1505,7 @@ static const struct memory_stat memory_stats[] = {
> > #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
> > { "zswap", MEMCG_ZSWAP_B },
> > { "zswapped", MEMCG_ZSWAPPED },
> > + { "zswap_wb", MEMCG_ZSWAP_WB },
>
> zswap_writeback would be more consistent with file_writeback below.
>
> Taking a step back, this is not really a "state". We increment it by 1
> every time and never decrement it. Sounds awfully similar to events :)
Ah yeah, this is probably closer to zswpin/zswpout counters :)
We can probably re-use that piece of logic.
>
> You can also use count_objcg_event() directly and avoid the need for
> obj_cgroup_report_zswap_wb() below.
>
> > #endif
> > { "file_mapped", NR_FILE_MAPPED },
> > { "file_dirty", NR_FILE_DIRTY },
> > @@ -1541,6 +1542,7 @@ static int memcg_page_state_unit(int item)
> > switch (item) {
> > case MEMCG_PERCPU_B:
> > case MEMCG_ZSWAP_B:
> > + case MEMCG_ZSWAP_WB:
> > case NR_SLAB_RECLAIMABLE_B:
> > case NR_SLAB_UNRECLAIMABLE_B:
> > case WORKINGSET_REFAULT_ANON:
> > @@ -7861,6 +7863,19 @@ void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size)
> > rcu_read_unlock();
> > }
> >
> > +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg)
> > +{
> > + struct mem_cgroup *memcg;
> > +
> > + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
> > + return;
> > +
> > + rcu_read_lock();
> > + memcg = obj_cgroup_memcg(objcg);
> > + mod_memcg_state(memcg, MEMCG_ZSWAP_WB, 1);
> > + rcu_read_unlock();
> > +}
> > +
> > static u64 zswap_current_read(struct cgroup_subsys_state *css,
> > struct cftype *cft)
> > {
> > diff --git a/mm/zswap.c b/mm/zswap.c
> > index d2989ad11814..15485427e3fa 100644
> > --- a/mm/zswap.c
> > +++ b/mm/zswap.c
> > @@ -704,6 +704,9 @@ static enum lru_status shrink_memcg_cb(struct list_head *item, struct list_lru_o
> > }
> > zswap_written_back_pages++;
> >
> > + if (entry->objcg)
> > + obj_cgroup_report_zswap_wb(entry->objcg);
> > +
> > /*
> > * Writeback started successfully, the page now belongs to the
> > * swapcache. Drop the entry from zswap - unless invalidate already
> > --
> > 2.34.1
On Tue, Oct 17, 2023 at 4:21 PM Nhat Pham <nphamcs@gmail.com> wrote:
>
> From: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
>
> Since zswap now writes back pages from memcg-specific LRUs, we now need a
> new stat to show writebacks count for each memcg.
>
> Suggested-by: Nhat Pham <nphamcs@gmail.com>
> Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com>
> Signed-off-by: Nhat Pham <nphamcs@gmail.com>
/s/Signed-off/Acked
This is Domenico's work :) I used the wrong tag here. Should be:
Acked-by: Nhat Pham <nphamcs@gmail.com>
> ---
> include/linux/memcontrol.h | 2 ++
> mm/memcontrol.c | 15 +++++++++++++++
> mm/zswap.c | 3 +++
> 3 files changed, 20 insertions(+)
>
> diff --git a/include/linux/memcontrol.h b/include/linux/memcontrol.h
> index 3de10fabea0f..7868b1e00bf5 100644
> --- a/include/linux/memcontrol.h
> +++ b/include/linux/memcontrol.h
> @@ -38,6 +38,7 @@ enum memcg_stat_item {
> MEMCG_KMEM,
> MEMCG_ZSWAP_B,
> MEMCG_ZSWAPPED,
> + MEMCG_ZSWAP_WB,
> MEMCG_NR_STAT,
> };
>
> @@ -1884,6 +1885,7 @@ static inline void count_objcg_event(struct obj_cgroup *objcg,
> bool obj_cgroup_may_zswap(struct obj_cgroup *objcg);
> void obj_cgroup_charge_zswap(struct obj_cgroup *objcg, size_t size);
> void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size);
> +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg);
> #else
> static inline bool obj_cgroup_may_zswap(struct obj_cgroup *objcg)
> {
> diff --git a/mm/memcontrol.c b/mm/memcontrol.c
> index 1bde67b29287..a9118871e5a6 100644
> --- a/mm/memcontrol.c
> +++ b/mm/memcontrol.c
> @@ -1505,6 +1505,7 @@ static const struct memory_stat memory_stats[] = {
> #if defined(CONFIG_MEMCG_KMEM) && defined(CONFIG_ZSWAP)
> { "zswap", MEMCG_ZSWAP_B },
> { "zswapped", MEMCG_ZSWAPPED },
> + { "zswap_wb", MEMCG_ZSWAP_WB },
> #endif
> { "file_mapped", NR_FILE_MAPPED },
> { "file_dirty", NR_FILE_DIRTY },
> @@ -1541,6 +1542,7 @@ static int memcg_page_state_unit(int item)
> switch (item) {
> case MEMCG_PERCPU_B:
> case MEMCG_ZSWAP_B:
> + case MEMCG_ZSWAP_WB:
> case NR_SLAB_RECLAIMABLE_B:
> case NR_SLAB_UNRECLAIMABLE_B:
> case WORKINGSET_REFAULT_ANON:
> @@ -7861,6 +7863,19 @@ void obj_cgroup_uncharge_zswap(struct obj_cgroup *objcg, size_t size)
> rcu_read_unlock();
> }
>
> +void obj_cgroup_report_zswap_wb(struct obj_cgroup *objcg)
> +{
> + struct mem_cgroup *memcg;
> +
> + if (!cgroup_subsys_on_dfl(memory_cgrp_subsys))
> + return;
> +
> + rcu_read_lock();
> + memcg = obj_cgroup_memcg(objcg);
> + mod_memcg_state(memcg, MEMCG_ZSWAP_WB, 1);
> + rcu_read_unlock();
> +}
> +
> static u64 zswap_current_read(struct cgroup_subsys_state *css,
> struct cftype *cft)
> {
> diff --git a/mm/zswap.c b/mm/zswap.c
> index d2989ad11814..15485427e3fa 100644
> --- a/mm/zswap.c
> +++ b/mm/zswap.c
> @@ -704,6 +704,9 @@ static enum lru_status shrink_memcg_cb(struct list_head *item, struct list_lru_o
> }
> zswap_written_back_pages++;
>
> + if (entry->objcg)
> + obj_cgroup_report_zswap_wb(entry->objcg);
> +
> /*
> * Writeback started successfully, the page now belongs to the
> * swapcache. Drop the entry from zswap - unless invalidate already
> --
> 2.34.1
On 10/17/2023 4:35 PM, Nhat Pham wrote: > On Tue, Oct 17, 2023 at 4:21 PM Nhat Pham <nphamcs@gmail.com> wrote: >> >> From: Domenico Cerasuolo <cerasuolodomenico@gmail.com> >> >> Since zswap now writes back pages from memcg-specific LRUs, we now need a >> new stat to show writebacks count for each memcg. >> >> Suggested-by: Nhat Pham <nphamcs@gmail.com> >> Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com> >> Signed-off-by: Nhat Pham <nphamcs@gmail.com> > > /s/Signed-off/Acked > This is Domenico's work :) I used the wrong tag here. Should be: > Acked-by: Nhat Pham <nphamcs@gmail.com> no, since you are posting the patch, you have to sign off on it. Signed-off-by is correct
On Tue, Oct 17, 2023 at 4:38 PM Jeff Johnson <quic_jjohnson@quicinc.com> wrote: > > On 10/17/2023 4:35 PM, Nhat Pham wrote: > > On Tue, Oct 17, 2023 at 4:21 PM Nhat Pham <nphamcs@gmail.com> wrote: > >> > >> From: Domenico Cerasuolo <cerasuolodomenico@gmail.com> > >> > >> Since zswap now writes back pages from memcg-specific LRUs, we now need a > >> new stat to show writebacks count for each memcg. > >> > >> Suggested-by: Nhat Pham <nphamcs@gmail.com> > >> Signed-off-by: Domenico Cerasuolo <cerasuolodomenico@gmail.com> > >> Signed-off-by: Nhat Pham <nphamcs@gmail.com> > > > > /s/Signed-off/Acked > > This is Domenico's work :) I used the wrong tag here. Should be: > > Acked-by: Nhat Pham <nphamcs@gmail.com> > > no, since you are posting the patch, you have to sign off on it. > Signed-off-by is correct > Ah so past Nhat was right all along. Ignore my comments then. Thanks for letting me know, Jeff!
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