From 60d8bae9d16a52346ba738518bd43702d15eb834 Mon Sep 17 00:00:00 2001 From: Bob Peterson Date: Wed, 6 Oct 2021 07:59:59 -0500 Subject: [PATCH] gfs2: further simplify do_promote This patch further simplifies function do_promote by eliminating some redundant code in favor of using a lock_released flag. This is just prep work for a future patch. Signed-off-by: Bob Peterson Signed-off-by: Andreas Gruenbacher --- fs/gfs2/glock.c | 43 +++++++++++++++++++++++-------------------- 1 file changed, 23 insertions(+), 20 deletions(-) diff --git a/fs/gfs2/glock.c b/fs/gfs2/glock.c index f9aebeba7454..db213f0ef960 100644 --- a/fs/gfs2/glock.c +++ b/fs/gfs2/glock.c @@ -487,12 +487,14 @@ __acquires(&gl->gl_lockref.lock) const struct gfs2_glock_operations *glops = gl->gl_ops; struct gfs2_holder *gh, *tmp, *first_gh; bool incompat_holders_demoted = false; + bool lock_released; int ret; restart: first_gh = find_first_strong_holder(gl); list_for_each_entry_safe(gh, tmp, &gl->gl_holders, gh_list) { - if (!test_bit(HIF_WAIT, &gh->gh_iflags)) + lock_released = false; + if (test_bit(HIF_HOLDER, &gh->gh_iflags)) continue; if (!may_grant(gl, first_gh, gh)) { /* @@ -511,30 +513,31 @@ restart: first_gh = gh; } if (gh->gh_list.prev == &gl->gl_holders && - glops->go_instantiate) { - if (!(gh->gh_flags & GL_SKIP)) { - spin_unlock(&gl->gl_lockref.lock); - /* FIXME: eliminate this eventually */ - ret = glops->go_instantiate(gh); - spin_lock(&gl->gl_lockref.lock); - if (ret) { - if (ret == 1) - return 2; - gh->gh_error = ret; - list_del_init(&gh->gh_list); - trace_gfs2_glock_queue(gh, 0); - gfs2_holder_wake(gh); - goto restart; - } + !(gh->gh_flags & GL_SKIP) && glops->go_instantiate) { + lock_released = true; + spin_unlock(&gl->gl_lockref.lock); + ret = glops->go_instantiate(gh); + spin_lock(&gl->gl_lockref.lock); + if (ret) { + if (ret == 1) + return 2; + gh->gh_error = ret; + list_del_init(&gh->gh_list); + trace_gfs2_glock_queue(gh, 0); + gfs2_holder_wake(gh); + goto restart; } - set_bit(HIF_HOLDER, &gh->gh_iflags); - trace_gfs2_promote(gh); - gfs2_holder_wake(gh); - goto restart; } set_bit(HIF_HOLDER, &gh->gh_iflags); trace_gfs2_promote(gh); gfs2_holder_wake(gh); + /* + * If we released the gl_lockref.lock the holders list may have + * changed. For that reason, we start again at the start of + * the holders queue. + */ + if (lock_released) + goto restart; } return 0; }