diff mbox series

[4/4] xmmap: inform Linux users of tuning knobs on ENOMEM

Message ID 20210629081108.28657-5-e@80x24.org (mailing list archive)
State New, archived
Headers show
Series gracefully handling mmap failures | expand

Commit Message

Eric Wong June 29, 2021, 8:11 a.m. UTC 
In cases where we can't (or haven't gotten around to) attempting
graceful handling of mmap failures, Linux users may benefit from
additional information on how to avoid the problem.

Signed-off-by: Eric Wong <e@80x24.org>
---
 object-file.c | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)
diff mbox series

Patch

diff --git a/object-file.c b/object-file.c
index 4c043f1f3c..4139a5ebe6 100644
--- a/object-file.c
+++ b/object-file.c
@@ -1027,8 +1027,14 @@  void *xmmap(void *start, size_t length,
 	int prot, int flags, int fd, off_t offset)
 {
 	void *ret = xmmap_gently(start, length, prot, flags, fd, offset);
-	if (ret == MAP_FAILED)
+	if (ret == MAP_FAILED) {
+#if defined(__linux__)
+		if (errno == ENOMEM)
+			die_errno(_(
+"mmap failed, check sys.vm.max_map_count and/or RLIMIT_DATA"));
+#endif /* OS-specific bits */
 		die_errno(_("mmap failed"));
+	}
 	return ret;
 }