| Message ID | 20231213013807.897742-2-schatzberg.dan@gmail.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | Add swappiness argument to memory.reclaim | expand |
在 2023/12/13 9:38, Dan Schatzberg 写道: > [????????? schatzberg.dan@gmail.com ????????? https://aka.ms/LearnAboutSenderIdentification,????????????] > > We use the constants 0 and 200 in a few places in the mm code when > referring to the min and max swappiness. This patch adds MIN_SWAPPINESS > and MAX_SWAPPINESS #defines to improve clarity. There are no functional > changes. > > Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com> > --- > include/linux/swap.h | 2 ++ > mm/memcontrol.c | 2 +- > mm/vmscan.c | 10 +++++----- > 3 files changed, 8 insertions(+), 6 deletions(-) > > diff --git a/include/linux/swap.h b/include/linux/swap.h > index f6dd6575b905..e2ab76c25b4a 100644 > --- a/include/linux/swap.h > +++ b/include/linux/swap.h > @@ -407,6 +407,8 @@ extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order, > > #define MEMCG_RECLAIM_MAY_SWAP (1 << 1) > #define MEMCG_RECLAIM_PROACTIVE (1 << 2) > +#define MIN_SWAPPINESS 0 > +#define MAX_SWAPPINESS 200 Do MAX_SWAPPINESS apply for all swapppiness? If so, maybe better change swappiness sysctl define: ``` sysctl.c: { .procname = "swappiness", .data = &vm_swappiness, .maxlen = sizeof(vm_swappiness), .mode = 0644, .proc_handler = proc_dointvec_minmax, .extra1 = SYSCTL_ZERO, .extra2 = SYSCTL_TWO_HUNDRED, }, ``` Here hard code swappiness in [0, 200], and now add a new define. And many other code hard reference 200 into max value of swappiness, like: ``` memcontrol.c: static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, struct cftype *cft, u64 val) { struct mem_cgroup *memcg = mem_cgroup_from_css(css); if (val > 200) return -EINVAL; if (!mem_cgroup_is_root(memcg)) memcg->swappiness = val; else vm_swappiness = val; return 0; } vmscan.c: /* * From 0 .. 200. Higher means more swappy. */ int vm_swappiness = 60; ``` > extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, > unsigned long nr_pages, > gfp_t gfp_mask, > diff --git a/mm/memcontrol.c b/mm/memcontrol.c > index 1c1061df9cd1..9748a6b88bb8 100644 > --- a/mm/memcontrol.c > +++ b/mm/memcontrol.c > @@ -4337,7 +4337,7 @@ static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, > { > struct mem_cgroup *memcg = mem_cgroup_from_css(css); > > - if (val > 200) > + if (val > MAX_SWAPPINESS) > return -EINVAL; > > if (!mem_cgroup_is_root(memcg)) > diff --git a/mm/vmscan.c b/mm/vmscan.c > index 506f8220c5fe..2aa671fe938b 100644 > --- a/mm/vmscan.c > +++ b/mm/vmscan.c > @@ -2403,7 +2403,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, > ap = swappiness * (total_cost + 1); > ap /= anon_cost + 1; > > - fp = (200 - swappiness) * (total_cost + 1); > + fp = (MAX_SWAPPINESS - swappiness) * (total_cost + 1); > fp /= file_cost + 1; > > fraction[0] = ap; > @@ -4400,7 +4400,7 @@ static int get_type_to_scan(struct lruvec *lruvec, int swappiness, int *tier_idx > { > int type, tier; > struct ctrl_pos sp, pv; > - int gain[ANON_AND_FILE] = { swappiness, 200 - swappiness }; > + int gain[ANON_AND_FILE] = { swappiness, MAX_SWAPPINESS - swappiness }; > > /* > * Compare the first tier of anon with that of file to determine which > @@ -4444,7 +4444,7 @@ static int isolate_folios(struct lruvec *lruvec, struct scan_control *sc, int sw > type = LRU_GEN_ANON; > else if (swappiness == 1) > type = LRU_GEN_FILE; > - else if (swappiness == 200) > + else if (swappiness == MAX_SWAPPINESS) > type = LRU_GEN_ANON; > else > type = get_type_to_scan(lruvec, swappiness, &tier); > @@ -5368,9 +5368,9 @@ static int run_cmd(char cmd, int memcg_id, int nid, unsigned long seq, > > lruvec = get_lruvec(memcg, nid); > > - if (swappiness < 0) > + if (swappiness < MIN_SWAPPINESS) > swappiness = get_swappiness(lruvec, sc); > - else if (swappiness > 200) > + else if (swappiness > MAX_SWAPPINESS) > goto done; > > switch (cmd) { > -- > 2.34.1 >
On Wed, Dec 13, 2023 at 09:58:26AM +0800, Huan Yang wrote: > > 在 2023/12/13 9:38, Dan Schatzberg 写道: > > [????????? schatzberg.dan@gmail.com ????????? https://aka.ms/LearnAboutSenderIdentification,????????????] > > > > We use the constants 0 and 200 in a few places in the mm code when > > referring to the min and max swappiness. This patch adds MIN_SWAPPINESS > > and MAX_SWAPPINESS #defines to improve clarity. There are no functional > > changes. > > > > Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com> > > --- > > include/linux/swap.h | 2 ++ > > mm/memcontrol.c | 2 +- > > mm/vmscan.c | 10 +++++----- > > 3 files changed, 8 insertions(+), 6 deletions(-) > > > > diff --git a/include/linux/swap.h b/include/linux/swap.h > > index f6dd6575b905..e2ab76c25b4a 100644 > > --- a/include/linux/swap.h > > +++ b/include/linux/swap.h > > @@ -407,6 +407,8 @@ extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order, > > > > #define MEMCG_RECLAIM_MAY_SWAP (1 << 1) > > #define MEMCG_RECLAIM_PROACTIVE (1 << 2) > > +#define MIN_SWAPPINESS 0 > > +#define MAX_SWAPPINESS 200 > > Do MAX_SWAPPINESS apply for all swapppiness? If so, maybe better change > swappiness sysctl define: > ``` > sysctl.c: > > { > .procname = "swappiness", > .data = &vm_swappiness, > .maxlen = sizeof(vm_swappiness), > .mode = 0644, > .proc_handler = proc_dointvec_minmax, > .extra1 = SYSCTL_ZERO, > .extra2 = SYSCTL_TWO_HUNDRED, > }, > > ``` > > Here hard code swappiness in [0, 200], and now add a new define. Yes, MAX_SWAPPINESS is a hard limit. I'm not sure what you're proposing here - the SYSCTL_ZERO and SYSCTL_TWO_HUNDRED values are a little different than the defines I added. I think most of the value is just consistently using the defines in the core mm code. > > And many other code hard reference 200 into max value of swappiness, like: > > ``` > memcontrol.c: > static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, > struct cftype *cft, u64 val) > { > struct mem_cgroup *memcg = mem_cgroup_from_css(css); > > if (val > 200) > return -EINVAL; > > if (!mem_cgroup_is_root(memcg)) > memcg->swappiness = val; > else > vm_swappiness = val; > > return 0; > } This one is already fixed in my patch.
在 2023/12/14 0:41, Dan Schatzberg 写道: > [Some people who received this message don't often get email from schatzberg.dan@gmail.com. Learn why this is important at https://aka.ms/LearnAboutSenderIdentification ] > > On Wed, Dec 13, 2023 at 09:58:26AM +0800, Huan Yang wrote: >> 在 2023/12/13 9:38, Dan Schatzberg 写道: >>> [????????? schatzberg.dan@gmail.com ????????? https://aka.ms/LearnAboutSenderIdentification,????????????] >>> >>> We use the constants 0 and 200 in a few places in the mm code when >>> referring to the min and max swappiness. This patch adds MIN_SWAPPINESS >>> and MAX_SWAPPINESS #defines to improve clarity. There are no functional >>> changes. >>> >>> Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com> >>> --- >>> include/linux/swap.h | 2 ++ >>> mm/memcontrol.c | 2 +- >>> mm/vmscan.c | 10 +++++----- >>> 3 files changed, 8 insertions(+), 6 deletions(-) >>> >>> diff --git a/include/linux/swap.h b/include/linux/swap.h >>> index f6dd6575b905..e2ab76c25b4a 100644 >>> --- a/include/linux/swap.h >>> +++ b/include/linux/swap.h >>> @@ -407,6 +407,8 @@ extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order, >>> >>> #define MEMCG_RECLAIM_MAY_SWAP (1 << 1) >>> #define MEMCG_RECLAIM_PROACTIVE (1 << 2) >>> +#define MIN_SWAPPINESS 0 >>> +#define MAX_SWAPPINESS 200 >> Do MAX_SWAPPINESS apply for all swapppiness? If so, maybe better change >> swappiness sysctl define: >> ``` >> sysctl.c: >> >> { >> .procname = "swappiness", >> .data = &vm_swappiness, >> .maxlen = sizeof(vm_swappiness), >> .mode = 0644, >> .proc_handler = proc_dointvec_minmax, >> .extra1 = SYSCTL_ZERO, >> .extra2 = SYSCTL_TWO_HUNDRED, >> }, >> >> ``` >> >> Here hard code swappiness in [0, 200], and now add a new define. > Yes, MAX_SWAPPINESS is a hard limit. I'm not sure what you're > proposing here - the SYSCTL_ZERO and SYSCTL_TWO_HUNDRED values are a I mean, MAX_SWAPPINESS and SYSCTL_TWO_HUNDRED all limit swappiness, but are different definitions. If swappiness change 200 into 400, you need to change here extra2 and your MAX_SWAPPINESS. It's wierd. > little different than the defines I added. I think most of the value > is just consistently using the defines in the core mm code. > >> And many other code hard reference 200 into max value of swappiness, like: >> >> ``` >> memcontrol.c: >> static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, >> struct cftype *cft, u64 val) >> { >> struct mem_cgroup *memcg = mem_cgroup_from_css(css); >> >> if (val > 200) >> return -EINVAL; >> >> if (!mem_cgroup_is_root(memcg)) >> memcg->swappiness = val; >> else >> vm_swappiness = val; >> >> return 0; >> } > This one is already fixed in my patch.
diff --git a/include/linux/swap.h b/include/linux/swap.h index f6dd6575b905..e2ab76c25b4a 100644 --- a/include/linux/swap.h +++ b/include/linux/swap.h @@ -407,6 +407,8 @@ extern unsigned long try_to_free_pages(struct zonelist *zonelist, int order, #define MEMCG_RECLAIM_MAY_SWAP (1 << 1) #define MEMCG_RECLAIM_PROACTIVE (1 << 2) +#define MIN_SWAPPINESS 0 +#define MAX_SWAPPINESS 200 extern unsigned long try_to_free_mem_cgroup_pages(struct mem_cgroup *memcg, unsigned long nr_pages, gfp_t gfp_mask, diff --git a/mm/memcontrol.c b/mm/memcontrol.c index 1c1061df9cd1..9748a6b88bb8 100644 --- a/mm/memcontrol.c +++ b/mm/memcontrol.c @@ -4337,7 +4337,7 @@ static int mem_cgroup_swappiness_write(struct cgroup_subsys_state *css, { struct mem_cgroup *memcg = mem_cgroup_from_css(css); - if (val > 200) + if (val > MAX_SWAPPINESS) return -EINVAL; if (!mem_cgroup_is_root(memcg)) diff --git a/mm/vmscan.c b/mm/vmscan.c index 506f8220c5fe..2aa671fe938b 100644 --- a/mm/vmscan.c +++ b/mm/vmscan.c @@ -2403,7 +2403,7 @@ static void get_scan_count(struct lruvec *lruvec, struct scan_control *sc, ap = swappiness * (total_cost + 1); ap /= anon_cost + 1; - fp = (200 - swappiness) * (total_cost + 1); + fp = (MAX_SWAPPINESS - swappiness) * (total_cost + 1); fp /= file_cost + 1; fraction[0] = ap; @@ -4400,7 +4400,7 @@ static int get_type_to_scan(struct lruvec *lruvec, int swappiness, int *tier_idx { int type, tier; struct ctrl_pos sp, pv; - int gain[ANON_AND_FILE] = { swappiness, 200 - swappiness }; + int gain[ANON_AND_FILE] = { swappiness, MAX_SWAPPINESS - swappiness }; /* * Compare the first tier of anon with that of file to determine which @@ -4444,7 +4444,7 @@ static int isolate_folios(struct lruvec *lruvec, struct scan_control *sc, int sw type = LRU_GEN_ANON; else if (swappiness == 1) type = LRU_GEN_FILE; - else if (swappiness == 200) + else if (swappiness == MAX_SWAPPINESS) type = LRU_GEN_ANON; else type = get_type_to_scan(lruvec, swappiness, &tier); @@ -5368,9 +5368,9 @@ static int run_cmd(char cmd, int memcg_id, int nid, unsigned long seq, lruvec = get_lruvec(memcg, nid); - if (swappiness < 0) + if (swappiness < MIN_SWAPPINESS) swappiness = get_swappiness(lruvec, sc); - else if (swappiness > 200) + else if (swappiness > MAX_SWAPPINESS) goto done; switch (cmd) {
We use the constants 0 and 200 in a few places in the mm code when referring to the min and max swappiness. This patch adds MIN_SWAPPINESS and MAX_SWAPPINESS #defines to improve clarity. There are no functional changes. Signed-off-by: Dan Schatzberg <schatzberg.dan@gmail.com> --- include/linux/swap.h | 2 ++ mm/memcontrol.c | 2 +- mm/vmscan.c | 10 +++++----- 3 files changed, 8 insertions(+), 6 deletions(-)