Commit 5c8ca473 authored by Mauricio Faria de Oliveira's avatar Mauricio Faria de Oliveira Committed by Andrew Morton
Browse files

mm/page_owner: add struct stack_print_ctx.flags 

Add the flags field to stack_print_ctx, and define two flags for current
behavior (printing stack traces and their number of base pages).

The plumbing of flags is debugfs_create_file(data) -> inode.i_private ->
page_owner_stack_open() -> stack_print_ctx.flags -> stack_print().

No behavior change intended.

Link: https://lkml.kernel.org/r/20251001175611.575861-3-mfo@igalia.com


Signed-off-by: default avatarMauricio Faria de Oliveira <mfo@igalia.com>
Reviewed-by: default avatarOscar Salvador <osalvador@suse.de>
Cc: Brendan Jackman <jackmanb@google.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Michal Hocko <mhocko@suse.com>
Cc: Suren Baghdasaryan <surenb@google.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Zi Yan <ziy@nvidia.com>
Signed-off-by: default avatarAndrew Morton <akpm@linux-foundation.org>
parent 156c0c5d

mm/page_owner.c

+23 −6
Original line number Diff line number Diff line
@@ -45,8 +45,12 @@ static struct stack failure_stack; 
static struct stack *stack_list;

static DEFINE_SPINLOCK(stack_list_lock);



#define STACK_PRINT_FLAG_STACK		0x1

#define STACK_PRINT_FLAG_PAGES		0x2



struct stack_print_ctx {

	struct stack *stack;

	u8 flags;

};



static bool page_owner_enabled __initdata;
@@ -904,19 +908,23 @@ static int stack_print(struct seq_file *m, void *v) 
	unsigned long *entries;

	unsigned long nr_entries;

	struct stack_record *stack_record = stack->stack_record;

	struct stack_print_ctx *ctx = m->private;



	if (!stack->stack_record)

		return 0;



	nr_entries = stack_record->size;

	entries = stack_record->entries;

	nr_base_pages = refcount_read(&stack_record->count) - 1;



	if (nr_base_pages < 1 || nr_base_pages < page_owner_pages_threshold)

		return 0;



	if (ctx->flags & STACK_PRINT_FLAG_STACK) {

		nr_entries = stack_record->size;

		entries = stack_record->entries;

		for (i = 0; i < nr_entries; i++)

			seq_printf(m, " %pS\n", (void *)entries[i]);

	}

	if (ctx->flags & STACK_PRINT_FLAG_PAGES)

		seq_printf(m, "nr_base_pages: %d\n\n", nr_base_pages);



	return 0;
@@ -938,6 +946,13 @@ static int page_owner_stack_open(struct inode *inode, struct file *file) 
	int ret = seq_open_private(file, &page_owner_stack_op,

				   sizeof(struct stack_print_ctx));



	if (!ret) {

		struct seq_file *m = file->private_data;

		struct stack_print_ctx *ctx = m->private;



		ctx->flags = (uintptr_t) inode->i_private;

	}



	return ret;

}
@@ -976,7 +991,9 @@ static int __init pageowner_init(void) 
	debugfs_create_file("page_owner", 0400, NULL, NULL,

			    &proc_page_owner_operations);

	dir = debugfs_create_dir("page_owner_stacks", NULL);

	debugfs_create_file("show_stacks", 0400, dir, NULL,

	debugfs_create_file("show_stacks", 0400, dir,

			    (void *)(STACK_PRINT_FLAG_STACK |

				     STACK_PRINT_FLAG_PAGES),

			    &page_owner_stack_operations);

	debugfs_create_file("count_threshold", 0600, dir, NULL,

			    &proc_page_owner_threshold);