[PATCH 11/12] fsmonitor: refactor bit invalidation in refresh callback

From: Jeff Hostetler via GitGitGadget <gitgitgadget@gmail.com>
Date: Feb 13, 2024, 20:52 UTC
Message-ID: <7775de735f41bdc601318cd15c3414f12b361a0c.1707857541.git.gitgitgadget@gmail.com>
In-Reply-To: <pull.1662.git.1707857541.gitgitgadget@gmail.com>

From: Jeff Hostetler <jeffhostetler@github.com>

Refactor code in the fsmonitor_refresh_callback() call chain dealing with invalidating the CE_FSMONITOR_VALID bit and add a trace message.

During the refresh, we clear the CE_FSMONITOR_VALID bit in response to data from the FSMonitor daemon (so that a later phase will lstat() and verify the true state of the file).

Create a new function to clear the bit and add some unique tracing for it to help debug edge cases.

This is similar to the existing `mark_fsmonitor_invalid()` function, but we don't need the extra stuff that it does.

Signed-off-by: Jeff Hostetler <jeffhostetler@github.com>
---
 fsmonitor.c | 20 +++++++++++++++++---
 1 file changed, 17 insertions(+), 3 deletions(-)

diff --git a/fsmonitor.c b/fsmonitor.c
index a7847f07a40..75c7f73f68d 100644
--- a/fsmonitor.c
+++ b/fsmonitor.c
@@ -209,6 +209,20 @@ static void my_invalidate_untracked_cache(
 	strbuf_release(&work_path);
 }
 
+/*
+ * Invalidate the FSM bit on this CE.  This is like mark_fsmonitor_invalid()
+ * but we've already handled the untracked-cache and I want a different
+ * trace message.
+ */
+static void my_invalidate_ce_fsm(struct cache_entry *ce)
+{
+	if (ce->ce_flags & CE_FSMONITOR_VALID)
+		trace_printf_key(&trace_fsmonitor,
+				 "fsmonitor_refresh_cb_invalidate '%s'",
+				 ce->name);
+	ce->ce_flags &= ~CE_FSMONITOR_VALID;
+}
+
 /*
  * Use the name-hash to lookup the pathname.
  *
@@ -240,7 +254,7 @@ static int my_callback_name_hash(
 
 	my_invalidate_untracked_cache(istate, ce->name, ce->ce_namelen);
 
-	ce->ce_flags &= ~CE_FSMONITOR_VALID;
+	my_invalidate_ce_fsm(ce);
 	return 1;
 }
 
@@ -312,7 +326,7 @@ static int fsmonitor_refresh_callback_unqualified(
 		 * cache-entry with the same pathname, nor for a cone
 		 * at that directory. (That is, assume no D/F conflicts.)
 		 */
-		istate->cache[pos]->ce_flags &= ~CE_FSMONITOR_VALID;
+		my_invalidate_ce_fsm(istate->cache[pos]);
 		return 1;
 	} else {
 		int nr_in_cone;
@@ -412,7 +426,7 @@ static int fsmonitor_refresh_callback_slash(
 	for (i = pos; i < istate->cache_nr; i++) {
 		if (!starts_with(istate->cache[i]->name, name))
 			break;
-		istate->cache[i]->ce_flags &= ~CE_FSMONITOR_VALID;
+		my_invalidate_ce_fsm(istate->cache[i]);
 		nr_in_cone++;
 	}

-- 
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