mm: vmstat: add cma statistics

Since CMA is used more widely, it's worth to have CMA allocation
statistics into vmstat.  With it, we could know how agressively system
uses cma allocation and how often it fails.

Link: https://lkml.kernel.org/r/20210302183346.3707237-1-minchan@kernel.org
Signed-off-by: Minchan Kim <minchan@kernel.org>
Reviewed-by: John Hubbard <jhubbard@nvidia.com>
Cc: John Dias <joaodias@google.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

diff --git a/include/linux/vm_event_item.h b/include/linux/vm_event_item.h
index 18e7597..21d7c7f 100644 (file)
--- a/include/linux/vm_event_item.h
+++ b/include/linux/vm_event_item.h
@@ -70,6 +70,10 @@ enum vm_event_item { PGPGIN, PGPGOUT, PSWPIN, PSWPOUT,
 #endif
 #ifdef CONFIG_HUGETLB_PAGE
                HTLB_BUDDY_PGALLOC, HTLB_BUDDY_PGALLOC_FAIL,
+#endif
+#ifdef CONFIG_CMA
+               CMA_ALLOC_SUCCESS,
+               CMA_ALLOC_FAIL,
 #endif
                UNEVICTABLE_PGCULLED,   /* culled to noreclaim list */
                UNEVICTABLE_PGSCANNED,  /* scanned for reclaimability */

diff --git a/mm/cma.c b/mm/cma.c
index acd6991..b44a71e 100644 (file)
--- a/mm/cma.c
+++ b/mm/cma.c
@@ -435,13 +435,13 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align,
        int ret = -ENOMEM;
 
        if (!cma || !cma->count || !cma->bitmap)
-               return NULL;
+               goto out;
 
        pr_debug("%s(cma %p, count %zu, align %d)\n", __func__, (void *)cma,
                 count, align);
 
        if (!count)
-               return NULL;
+               goto out;
 
        mask = cma_bitmap_aligned_mask(cma, align);
        offset = cma_bitmap_aligned_offset(cma, align);
@@ -449,7 +449,7 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align,
        bitmap_count = cma_bitmap_pages_to_bits(cma, count);
 
        if (bitmap_count > bitmap_maxno)
-               return NULL;
+               goto out;
 
        for (;;) {
                spin_lock_irq(&cma->lock);
@@ -506,6 +506,12 @@ struct page *cma_alloc(struct cma *cma, size_t count, unsigned int align,
        }
 
        pr_debug("%s(): returned %p\n", __func__, page);
+out:
+       if (page)
+               count_vm_event(CMA_ALLOC_SUCCESS);
+       else
+               count_vm_event(CMA_ALLOC_FAIL);
+
        return page;
 }
 

diff --git a/mm/vmstat.c b/mm/vmstat.c
index 74b2c37..49a8456 100644 (file)
--- a/mm/vmstat.c
+++ b/mm/vmstat.c
@@ -1312,6 +1312,10 @@ const char * const vmstat_text[] = {
 #ifdef CONFIG_HUGETLB_PAGE
        "htlb_buddy_alloc_success",
        "htlb_buddy_alloc_fail",
+#endif
+#ifdef CONFIG_CMA
+       "cma_alloc_success",
+       "cma_alloc_fail",
 #endif
        "unevictable_pgs_culled",
        "unevictable_pgs_scanned",