On this v5 I've split up the first patch into 3, one for comments, another for context / might_sleep() updates, and the last the big revert back to synchronous request_queue removal. I didn't update the context for the put / decrements for gendisk & request_queue as they would be updated in the next patch. Since the first 3 patches are a reflection of the original one, I've left the Reviewed-by's collected in place. I've changed the kzalloc() / snprintf() to just kasprintf() as requested by Bart. Since it was not clear that we don't have the bdev on do_blk_trace_setup() for the patch titled "blktrace: break out of blktrace setup on concurrent calls", I've added a comment so that someone doesn't later try to add a dev_printk() or the like. I've also addressed a compilation issue with debugfs disabled reported by 0-day on the patch titled "blktrace: fix debugfs use after free". It was missing a "static inline" on a function. I've also moved the new declarations underneath the "#ifdef CONFIG_BLOCK" on include/linux/genhd.h, I previously had them outside of this block. I've left in place the scsi-generic blktrace suppport given I didn't receive any feedback to kill it. This ensures this works as it used to. Since these are minor changes I've given this a spin with break-blktrace tests I have written and also ran blktrace with a scsi-generic media changer. Both sg0 (the controller) and sg1 worked as expected. These changes are based on linux-next tag next-20200515, and can also be found on my git tree: https://git.kernel.org/pub/scm/linux/kernel/git/mcgrof/linux-next.git/log/?h=20200515-blktrace-fixes Luis Chamberlain (7): block: add docs for gendisk / request_queue refcount helpers block: clarify context for gendisk / request_queue refcount increment helpers block: revert back to synchronous request_queue removal block: move main block debugfs initialization to its own file blktrace: fix debugfs use after free blktrace: break out of blktrace setup on concurrent calls loop: be paranoid on exit and prevent new additions / removals block/Makefile | 10 +- block/blk-core.c | 32 ++++-- block/blk-debugfs.c | 197 +++++++++++++++++++++++++++++++++++ block/blk-mq-debugfs.c | 5 - block/blk-sysfs.c | 46 ++++---- block/blk.h | 24 +++++ block/bsg.c | 2 + block/genhd.c | 73 ++++++++++++- block/partitions/core.c | 9 ++ drivers/block/loop.c | 4 + drivers/scsi/ch.c | 1 + drivers/scsi/sg.c | 75 +++++++++++++ drivers/scsi/st.c | 2 + include/linux/blkdev.h | 6 +- include/linux/blktrace_api.h | 1 - include/linux/genhd.h | 69 ++++++++++++ kernel/trace/blktrace.c | 37 +++++-- 17 files changed, 545 insertions(+), 48 deletions(-) create mode 100644 block/blk-debugfs.c -- 2.26.2
