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| author |   Marco Elver <elver@google.com> | 2021-09-07 19:56:21 -0700 |
|---|---|---|
| committer |   Linus Torvalds <torvalds@linux-foundation.org> | 2021-09-08 11:50:24 -0700 |
| commit | 4bbf04aa9aa88ae41205e387d35743a9bf5e933d (patch) | |
| tree | a1ecd87116814143015200c912623f34311ebe82 /mm/kfence/report.c | |
| parent | mm/secretmem: use refcount_t instead of atomic_t (diff) | |
| download | linux-dev-4bbf04aa9aa88ae41205e387d35743a9bf5e933d.tar.xz linux-dev-4bbf04aa9aa88ae41205e387d35743a9bf5e933d.zip | |
kfence: show cpu and timestamp in alloc/free info
Record cpu and timestamp on allocations and frees, and show them in
reports. Upon an error, this can help correlate earlier messages in the
kernel log via allocation and free timestamps.
Link: https://lkml.kernel.org/r/20210714175312.2947941-1-elver@google.com
Suggested-by: Joern Engel <joern@purestorage.com>
Signed-off-by: Marco Elver <elver@google.com>
Acked-by: Alexander Potapenko <glider@google.com>
Acked-by: Joern Engel <joern@purestorage.com>
Cc: Yuanyuan Zhong <yzhong@purestorage.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to '')
| -rw-r--r-- | mm/kfence/report.c | 19 |
1 files changed, 13 insertions, 6 deletions
diff --git a/mm/kfence/report.c b/mm/kfence/report.c index 2a319c21c939..cbdd8d442d0b 100644 --- a/mm/kfence/report.c +++ b/mm/kfence/report.c @@ -9,6 +9,7 @@ #include <linux/kernel.h> #include <linux/lockdep.h> +#include <linux/math.h> #include <linux/printk.h> #include <linux/sched/debug.h> #include <linux/seq_file.h> @@ -100,6 +101,13 @@ static void kfence_print_stack(struct seq_file *seq, const struct kfence_metadat bool show_alloc) { const struct kfence_track *track = show_alloc ? &meta->alloc_track : &meta->free_track; + u64 ts_sec = track->ts_nsec; + unsigned long rem_nsec = do_div(ts_sec, NSEC_PER_SEC); + + /* Timestamp matches printk timestamp format. */ + seq_con_printf(seq, "%s by task %d on cpu %d at %lu.%06lus:\n", + show_alloc ? "allocated" : "freed", track->pid, + track->cpu, (unsigned long)ts_sec, rem_nsec / 1000); if (track->num_stack_entries) { /* Skip allocation/free internals stack. */ @@ -126,15 +134,14 @@ void kfence_print_object(struct seq_file *seq, const struct kfence_metadata *met return; } - seq_con_printf(seq, - "kfence-#%td [0x%p-0x%p" - ", size=%d, cache=%s] allocated by task %d:\n", - meta - kfence_metadata, (void *)start, (void *)(start + size - 1), size, - (cache && cache->name) ? cache->name : "<destroyed>", meta->alloc_track.pid); + seq_con_printf(seq, "kfence-#%td: 0x%p-0x%p, size=%d, cache=%s\n\n", + meta - kfence_metadata, (void *)start, (void *)(start + size - 1), + size, (cache && cache->name) ? cache->name : "<destroyed>"); + kfence_print_stack(seq, meta, true); if (meta->state == KFENCE_OBJECT_FREED) { - seq_con_printf(seq, "\nfreed by task %d:\n", meta->free_track.pid); + seq_con_printf(seq, "\n"); kfence_print_stack(seq, meta, false); } } |