From: Johannes Berg <johannes.berg@xxxxxxxxx> Subject: gcov: simplify buffer allocation Use just a single vmalloc() with struct_size() instead of a separate kmalloc() for the iter struct. Link: https://lkml.kernel.org/r/20210315235453.b6de4a92096e.Iac40a5166589cefbff8449e466bd1b38ea7a17af@changeid Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx> Cc: Peter Oberparleiter <oberpar@xxxxxxxxxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- kernel/gcov/fs.c | 24 +++++++++--------------- 1 file changed, 9 insertions(+), 15 deletions(-) --- a/kernel/gcov/fs.c~gcov-simplify-buffer-allocation +++ a/kernel/gcov/fs.c @@ -97,9 +97,9 @@ __setup("gcov_persist=", gcov_persist_se */ struct gcov_iterator { struct gcov_info *info; - void *buffer; size_t size; loff_t pos; + char buffer[]; }; /** @@ -111,25 +111,20 @@ struct gcov_iterator { static struct gcov_iterator *gcov_iter_new(struct gcov_info *info) { struct gcov_iterator *iter; + size_t size; + + /* Dry-run to get the actual buffer size. */ + size = convert_to_gcda(NULL, info); - iter = kzalloc(sizeof(struct gcov_iterator), GFP_KERNEL); + iter = vmalloc(struct_size(iter, buffer, size)); if (!iter) - goto err_free; + return NULL; iter->info = info; - /* Dry-run to get the actual buffer size. */ - iter->size = convert_to_gcda(NULL, info); - iter->buffer = vmalloc(iter->size); - if (!iter->buffer) - goto err_free; - + iter->size = size; convert_to_gcda(iter->buffer, info); return iter; - -err_free: - kfree(iter); - return NULL; } @@ -139,8 +134,7 @@ err_free: */ static void gcov_iter_free(struct gcov_iterator *iter) { - vfree(iter->buffer); - kfree(iter); + vfree(iter); } /** _