[kbuild-all] Re: [linux-next:master 6373/10489] fs/xfs/xfs_log_cil.c:897:1-10: second lock on line 900 (fwd)

On Thu, Jun 17, 2021 at 11:50:44AM -0700, Darrick J. Wong wrote: > On Thu, Jun 17, 2021 at 08:28:24PM +0200, Julia Lawall wrote: > > cocci warnings: (new ones prefixed by >>) > > >> fs/xfs/xfs_log_cil.c:897:1-10: second lock on line 900 > > > > 5fd9256ce156ef Dave Chinner 2021-06-03 891 /* > > 5fd9256ce156ef Dave Chinner 2021-06-03 892 * If the checkpoint spans multiple iclogs, wait for all previous > > cb1acb3f324636 Dave Chinner 2021-06-04 893 * iclogs to complete before we submit the commit_iclog. In this case, > > cb1acb3f324636 Dave Chinner 2021-06-04 894 * the commit_iclog write needs to issue a pre-flush so that the > > cb1acb3f324636 Dave Chinner 2021-06-04 895 * ordering is correctly preserved down to stable storage. > > 5fd9256ce156ef Dave Chinner 2021-06-03 896 */ > > 5fd9256ce156ef Dave Chinner 2021-06-03 @897 spin_lock(&log->l_icloglock); > > cb1acb3f324636 Dave Chinner 2021-06-04 898 if (ctx->start_lsn != commit_lsn) { > > 5fd9256ce156ef Dave Chinner 2021-06-03 899 xlog_wait_on_iclog(commit_iclog->ic_prev); > > cb1acb3f324636 Dave Chinner 2021-06-04 @900 spin_lock(&log->l_icloglock); > > xlog_wait_on_commit drops l_icloglock, either directly or via xlog_wait. > It looks odd (perhaps there should be a comment?) but at least in theory > the functions are annotated so I guess that means the static checking > doesn't know that commit_iclog->ic_log == log? I think it's hard for a tool to reach into fs/xfs/xfs_log.c and look for the __releases annotation on the definition of xlog_wait_on_commit(). Should we also annotate the prototype in fs/xfs/xfs_log_priv.h ? For example, void wbc_attach_and_unlock_inode(struct writeback_control *wbc, struct inode *inode) __releases(&inode->i_lock);