From a38568a0b46d4a0dbe48f4642cbe2f885c525643 Mon Sep 17 00:00:00 2001 From: Suren Baghdasaryan Date: Tue, 14 May 2024 09:31:28 -0700 Subject: [PATCH] lib: add version into /proc/allocinfo output 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 # 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 [akpm@linux-foundation.org: remove stray newline from struct allocinfo_private] Link: https://lkml.kernel.org/r/20240514163128.3662251-1-surenb@google.com Signed-off-by: Suren Baghdasaryan Reviewed-by: Pasha Tatashin Reviewed-by: Kees Cook Cc: Kent Overstreet Cc: Vlastimil Babka Signed-off-by: Andrew Morton --- Documentation/filesystems/proc.rst | 5 ++-- lib/alloc_tag.c | 47 ++++++++++++++++++++---------- 2 files changed, 35 insertions(+), 17 deletions(-) diff --git a/Documentation/filesystems/proc.rst b/Documentation/filesystems/proc.rst index 4d97258a7954..7c3a565ffbef 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..11ed973ac359 100644 --- a/lib/alloc_tag.c +++ b/lib/alloc_tag.c @@ -16,47 +16,60 @@ 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, "# \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 +84,17 @@ 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; }