| Message ID | 20191023173423.12532-2-longman@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [1/2] mm, vmstat: Release zone lock more frequently when reading /proc/pagetypeinfo | expand |
On Wed 23-10-19 13:34:23, Waiman Long wrote: [...] > @@ -1419,6 +1419,17 @@ static void pagetypeinfo_showfree_print(struct seq_file *m, > } > seq_putc(m, '\n'); > } > + > + /* > + * List total free blocks per order > + */ > + seq_printf(m, "Node %4d, zone %8s, total ", > + pgdat->node_id, zone->name); > + for (order = 0; order < MAX_ORDER; ++order) { > + area = &(zone->free_area[order]); > + seq_printf(m, "%6lu ", area->nr_free); > + } > + seq_putc(m, '\n'); This is essentially duplicating /proc/buddyinfo. Do we really need that?
On 10/23/19 2:02 PM, Michal Hocko wrote: > On Wed 23-10-19 13:34:23, Waiman Long wrote: > [...] >> @@ -1419,6 +1419,17 @@ static void pagetypeinfo_showfree_print(struct seq_file *m, >> } >> seq_putc(m, '\n'); >> } >> + >> + /* >> + * List total free blocks per order >> + */ >> + seq_printf(m, "Node %4d, zone %8s, total ", >> + pgdat->node_id, zone->name); >> + for (order = 0; order < MAX_ORDER; ++order) { >> + area = &(zone->free_area[order]); >> + seq_printf(m, "%6lu ", area->nr_free); >> + } >> + seq_putc(m, '\n'); > This is essentially duplicating /proc/buddyinfo. Do we really need that? Yes, you are right. As the information is available elsewhere. I am fine with dropping this. Cheers, Longman
diff --git a/mm/vmstat.c b/mm/vmstat.c index c5b82fdf54af..172946d8f358 100644 --- a/mm/vmstat.c +++ b/mm/vmstat.c @@ -1373,6 +1373,7 @@ static void pagetypeinfo_showfree_print(struct seq_file *m, pg_data_t *pgdat, struct zone *zone) { int order, mtype; + struct free_area *area; unsigned long iteration_count = 0; for (mtype = 0; mtype < MIGRATE_TYPES; mtype++) { @@ -1382,7 +1383,6 @@ static void pagetypeinfo_showfree_print(struct seq_file *m, migratetype_names[mtype]); for (order = 0; order < MAX_ORDER; ++order) { unsigned long freecount = 0; - struct free_area *area; struct list_head *curr; bool overflow = false; @@ -1419,6 +1419,17 @@ static void pagetypeinfo_showfree_print(struct seq_file *m, } seq_putc(m, '\n'); } + + /* + * List total free blocks per order + */ + seq_printf(m, "Node %4d, zone %8s, total ", + pgdat->node_id, zone->name); + for (order = 0; order < MAX_ORDER; ++order) { + area = &(zone->free_area[order]); + seq_printf(m, "%6lu ", area->nr_free); + } + seq_putc(m, '\n'); } /* Print out the free pages at each order for each migatetype */
Now that the free block count for each migration types in /proc/pagetypeinfo may not show the exact count if it excceeds 100,000. Users may not know how much more the counts will be. As the free_area structure has already tracked the total free block count in nr_free, we may as well print it out with no additional cost. That will give users a rough idea of where the upper bounds will be. If there is no overflow, the presence of the total counts will also enable us to check if the nr_free counts match the total number of entries in the free lists. Signed-off-by: Waiman Long <longman@redhat.com> --- mm/vmstat.c | 13 ++++++++++++- 1 file changed, 12 insertions(+), 1 deletion(-)