On Fri, Nov 3, 2023 at 5:45 PM Shijie Huang <shijie@amperemail.onmicrosoft.com> wrote:

Hi Lianbo,

在 2023/11/3 17:27, lijiang 写道:

On Thu, Nov 2, 2023 at 9:35 AM Huang Shijie <shijie@os.amperecomputing.com> wrote:

In the NUMA machine, it is useful to know the memory distribution of
an inode page cache:
How many pages in the node 0?
How many pages in the node 1?

Add "files -n" command to get the memory distribution information:
1.) Add new argument for dump_inode_page_cache_info()
2.) make page_to_nid() a global function.
3.) Add summary_inode_page() to check each page's node
information.
4.) Use print_inode_summary_info() to print the
memory distribution information of an inode.

Signed-off-by: Huang Shijie <shijie@os.amperecomputing.com>
---
v2 --> v3:
1.) Always return 1 for summary_inode_page().
2.) Add more comment for help_files.

Thank you for the update, Shijie.

---
defs.h | 1 +
filesys.c | 53 ++++++++++++++++++++++++++++++++++++++++++++++++-----
help.c | 14 +++++++++++++-
memory.c | 3 +--
4 files changed, 63 insertions(+), 8 deletions(-)

diff --git a/defs.h b/defs.h
index 788f63a..1fe2d0b 100644
--- a/defs.h
+++ b/defs.h
@@ -5750,6 +5750,7 @@ int dump_inode_page(ulong);
ulong valid_section_nr(ulong);
void display_memory_from_file_offset(ulonglong, long, void *);
void swap_info_init(void);
+int page_to_nid(ulong);

/*
* filesys.c
diff --git a/filesys.c b/filesys.c
index 1d0ee7f..2c7cc74 100644
--- a/filesys.c
+++ b/filesys.c
@@ -49,7 +49,7 @@ static int match_file_string(char *, char *, char *);
static ulong get_root_vfsmount(char *);
static void check_live_arch_mismatch(void);
static long get_inode_nrpages(ulong);
-static void dump_inode_page_cache_info(ulong);
+static void dump_inode_page_cache_info(ulong, void *callback);

#define DENTRY_CACHE (20)
#define INODE_CACHE (20)
@@ -2192,8 +2192,31 @@ get_inode_nrpages(ulong i_mapping)
return nrpages;
}

+/* Used to collect the numa information for an inode */
+static ulong *numa_node;
+
+static void
+print_inode_summary_info(void)
+{
+ int i;
+
+ fprintf(fp, " NODE PAGES\n");
+ for (i = 0; i < vt->numnodes; i++)
+ fprintf(fp, " %2d %8ld\n", i, numa_node[i]);
+}
+
+static int
+summary_inode_page(ulong page)
+{
+ int node = page_to_nid(page);
+
+ if (0 <= node && node < vt->numnodes)
+ numa_node[node]++;
+ return 1;
+}

A clear error message would be nice when the "files -n" command fails. What's your opinion on the following changes?

ok, no problem.

I did not met the "error" message with the /proc/kcore.

Maybe there are error message in the kernel crash core file.

+summary_inode_page(ulong page)
+{
+ int node;
+
+ if (!is_page_ptr(page, NULL))
+ error(FATAL, "Invalid inode page(0x%lx)\n", page);
+

Is this redandent?

The is_page_ptr() is called in page_to_nid();

It's true.

page_to_nid()->

page_to_phys()->

is_page_ptr()

But it may be worth sacrificing a little performance for helping with the debugging, if there is no better approach. Or need to refactor the relevant code? Looks