Add version string and a header at the beginning of /proc/allocinfo to
allow later format changes. Example output:
> head /proc/allocinfo
allocinfo - version: 1.0
# <size> <calls> <tag info>
0 0 init/main.c:1314 func:do_initcalls
0 0 init/do_mounts.c:353 func:mount_nodev_root
0 0 init/do_mounts.c:187 func:mount_root_generic
0 0 init/do_mounts.c:158 func:do_mount_root
0 0 init/initramfs.c:493 func:unpack_to_rootfs
0 0 init/initramfs.c:492 func:unpack_to_rootfs
0 0 init/initramfs.c:491 func:unpack_to_rootfs
512 1 arch/x86/events/rapl.c:681 func:init_rapl_pmus
128 1 arch/x86/events/rapl.c:571 func:rapl_cpu_online
Signed-off-by: Suren Baghdasaryan <surenb@xxxxxxxxxx>
---
Changes since v1 [1]:
- Added header with field names, per Pasha Tatashin
- Fixed a spelling error in the changelog
[1] https://lore.kernel.org/all/20240514153532.3622371-1-surenb@xxxxxxxxxx/
Documentation/filesystems/proc.rst | 5 ++--
lib/alloc_tag.c | 48 ++++++++++++++++++++----------
2 files changed, 36 insertions(+), 17 deletions(-)
diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst
index 245269dd6e02..4b71b3903d46 100644
--- a/Documentation/filesystems/proc.rst
+++ b/Documentation/filesystems/proc.rst
@@ -961,13 +961,14 @@ Provides information about memory allocations at all locations in the code
base. Each allocation in the code is identified by its source file, line
number, module (if originates from a loadable module) and the function calling
the allocation. The number of bytes allocated and number of calls at each
-location are reported.
+location are reported. The first line indicates the version of the file, the
+second line is the header listing fields in the file.
Example output.
::
- > sort -rn /proc/allocinfo
+ > tail -n +3 /proc/allocinfo | sort -rn
127664128 31168 mm/page_ext.c:270 func:alloc_page_ext
56373248 4737 mm/slub.c:2259 func:alloc_slab_page
14880768 3633 mm/readahead.c:247 func:page_cache_ra_unbounded
diff --git a/lib/alloc_tag.c b/lib/alloc_tag.c
index 531dbe2f5456..cbe93939332d 100644
--- a/lib/alloc_tag.c
+++ b/lib/alloc_tag.c
@@ -16,47 +16,61 @@ EXPORT_SYMBOL(_shared_alloc_tag);
DEFINE_STATIC_KEY_MAYBE(CONFIG_MEM_ALLOC_PROFILING_ENABLED_BY_DEFAULT,
mem_alloc_profiling_key);
+struct allocinfo_private {
+ struct codetag_iterator iter;
+ bool print_header;
+
+};
+
static void *allocinfo_start(struct seq_file *m, loff_t *pos)
{
- struct codetag_iterator *iter;
+ struct allocinfo_private *priv;
struct codetag *ct;
loff_t node = *pos;
- iter = kzalloc(sizeof(*iter), GFP_KERNEL);
- m->private = iter;
- if (!iter)
+ priv = kzalloc(sizeof(*priv), GFP_KERNEL);
+ m->private = priv;
+ if (!priv)
return NULL;
+ priv->print_header = (node == 0);
codetag_lock_module_list(alloc_tag_cttype, true);
- *iter = codetag_get_ct_iter(alloc_tag_cttype);
- while ((ct = codetag_next_ct(iter)) != NULL && node)
+ priv->iter = codetag_get_ct_iter(alloc_tag_cttype);
+ while ((ct = codetag_next_ct(&priv->iter)) != NULL && node)
node--;
- return ct ? iter : NULL;
+ return ct ? priv : NULL;
}
static void *allocinfo_next(struct seq_file *m, void *arg, loff_t *pos)
{
- struct codetag_iterator *iter = (struct codetag_iterator *)arg;
- struct codetag *ct = codetag_next_ct(iter);
+ struct allocinfo_private *priv = (struct allocinfo_private *)arg;
+ struct codetag *ct = codetag_next_ct(&priv->iter);
(*pos)++;
if (!ct)
return NULL;
- return iter;
+ return priv;
}
static void allocinfo_stop(struct seq_file *m, void *arg)
{
- struct codetag_iterator *iter = (struct codetag_iterator *)m->private;
+ struct allocinfo_private *priv = (struct allocinfo_private *)m->private;
- if (iter) {
+ if (priv) {
codetag_lock_module_list(alloc_tag_cttype, false);
- kfree(iter);
+ kfree(priv);
}
}
+static void print_allocinfo_header(struct seq_buf *buf)
+{
+ /* Output format version, so we can change it. */
+ seq_buf_printf(buf, "allocinfo - version: 1.0\n");
+ seq_buf_printf(buf, "# <size> <calls> <tag info>\n");
+}
+
static void alloc_tag_to_text(struct seq_buf *out, struct codetag *ct)
{
struct alloc_tag *tag = ct_to_alloc_tag(ct);
@@ -71,13 +85,17 @@ static void alloc_tag_to_text(struct seq_buf *out, struct codetag *ct)
static int allocinfo_show(struct seq_file *m, void *arg)
{
- struct codetag_iterator *iter = (struct codetag_iterator *)arg;
+ struct allocinfo_private *priv = (struct allocinfo_private *)arg;
char *bufp;
size_t n = seq_get_buf(m, &bufp);
struct seq_buf buf;
seq_buf_init(&buf, bufp, n);
- alloc_tag_to_text(&buf, iter->ct);
+ if (priv->print_header) {
+ print_allocinfo_header(&buf);
+ priv->print_header = false;
+ }
+ alloc_tag_to_text(&buf, priv->iter.ct);
seq_commit(m, seq_buf_used(&buf));
return 0;
}
base-commit: 7e8aafe0636cdcc5c9699ced05ff1f8ffcb937e2
--
2.45.0.rc1.225.g2a3ae87e7f-goog
