From 35f5197009cae284cec9beb8b2692d2321a5bd3c Mon Sep 17 00:00:00 2001 From: Kent Overstreet Date: Sat, 25 Jan 2025 19:22:50 -0500 Subject: bcachefs: Improve journal pin flushing Running the preempt tiering tests with a lower than normal journal reclaim delay turned up a shutdown hang - a lost wakeup, caused because flushing a journal pin (e.g. key cache/write buffer) can generate a new journal pin. The "simple" fix of adding the correct wakeup didn't work because of ordering issues; if we flush btree node pins too aggressively before other pins have completed, we end up spinning where each flush iteration generates new work. So to fix this correctly: - The list of flushed journal pins is now broken out by type, so that we can wait for key cache/write buffer pin flushing to complete before flushing dirty btree nodes - A new closure_waitlist is added for bch2_journal_flush_pins; this one is only used under or when we're taking the journal lock, so it's pretty cheap to add rigorously correct wakeups to journal_pin_set() and journal_pin_drop(). Additionally, bch2_journal_seq_pins_to_text() is moved to journal_reclaim.c, where it belongs, along with a bit of other small renaming and refactoring. Besides fixing the hang, the better ordering between key cache/write buffer flushing and btree node flushing should help or fix the "unmount taking excessively long" a few users have been noticing. Signed-off-by: Kent Overstreet --- fs/bcachefs/debug.c | 1 + 1 file changed, 1 insertion(+) (limited to 'fs/bcachefs/debug.c') diff --git a/fs/bcachefs/debug.c b/fs/bcachefs/debug.c index b5de52a50d10..55333e82d1fe 100644 --- a/fs/bcachefs/debug.c +++ b/fs/bcachefs/debug.c @@ -20,6 +20,7 @@ #include "extents.h" #include "fsck.h" #include "inode.h" +#include "journal_reclaim.h" #include "super.h" #include -- cgit v1.2.3