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Thu, 18 Feb 2021 16:54:09 +0000 From: Allison Henderson To: linux-xfs@vger.kernel.org Subject: [PATCH v15 13/22] xfs: Add state machine tracepoints Date: Thu, 18 Feb 2021 09:53:39 -0700 Message-Id: <20210218165348.4754-14-allison.henderson@oracle.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20210218165348.4754-1-allison.henderson@oracle.com> References: <20210218165348.4754-1-allison.henderson@oracle.com> Content-Type: text/plain X-Originating-IP: [67.1.223.248] X-ClientProxiedBy: SJ0PR03CA0352.namprd03.prod.outlook.com (2603:10b6:a03:39c::27) To BY5PR10MB4306.namprd10.prod.outlook.com (2603:10b6:a03:211::7) MIME-Version: 1.0 X-MS-Exchange-MessageSentRepresentingType: 1 Received: from localhost.localdomain (67.1.223.248) by SJ0PR03CA0352.namprd03.prod.outlook.com (2603:10b6:a03:39c::27) with Microsoft SMTP Server (version=TLS1_2, cipher=TLS_ECDHE_RSA_WITH_AES_256_GCM_SHA384) id 15.20.3868.27 via Frontend Transport; Thu, 18 Feb 2021 16:54:08 +0000 X-MS-PublicTrafficType: Email X-MS-Office365-Filtering-Correlation-Id: c7946b9a-94b4-4013-79f2-08d8d42dcf55 X-MS-TrafficTypeDiagnostic: BYAPR10MB3381: X-Microsoft-Antispam-PRVS: X-MS-Oob-TLC-OOBClassifiers: OLM:1360; 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We use this to track when ever a new state is set or -EAGAIN is returned Signed-off-by: Allison Henderson --- fs/xfs/libxfs/xfs_attr.c | 31 ++++++++++++++++++++++++++++++- fs/xfs/libxfs/xfs_attr_remote.c | 1 + fs/xfs/xfs_trace.h | 25 +++++++++++++++++++++++++ 3 files changed, 56 insertions(+), 1 deletion(-) diff --git a/fs/xfs/libxfs/xfs_attr.c b/fs/xfs/libxfs/xfs_attr.c index c7b86d5..ba21475 100644 --- a/fs/xfs/libxfs/xfs_attr.c +++ b/fs/xfs/libxfs/xfs_attr.c @@ -313,6 +313,7 @@ xfs_attr_set_fmt( * the attr fork to leaf format and will restart with the leaf * add. */ + trace_xfs_attr_set_fmt_return(XFS_DAS_UNINIT, args->dp); dac->flags |= XFS_DAC_DEFER_FINISH; return -EAGAIN; } @@ -378,6 +379,8 @@ xfs_attr_set_iter( * handling code below */ dac->flags |= XFS_DAC_DEFER_FINISH; + trace_xfs_attr_set_iter_return( + dac->dela_state, args->dp); return -EAGAIN; } else if (error) @@ -400,10 +403,13 @@ xfs_attr_set_iter( return error; dac->dela_state = XFS_DAS_FOUND_NBLK; + trace_xfs_attr_set_iter_return(dac->dela_state, + args->dp); return -EAGAIN; } dac->dela_state = XFS_DAS_FOUND_LBLK; + trace_xfs_attr_set_iter_return(dac->dela_state, args->dp); return -EAGAIN; case XFS_DAS_FOUND_LBLK: @@ -433,6 +439,8 @@ xfs_attr_set_iter( if (error) return error; + trace_xfs_attr_set_iter_return(dac->dela_state, + args->dp); return -EAGAIN; } @@ -469,6 +477,7 @@ xfs_attr_set_iter( * series. */ dac->dela_state = XFS_DAS_FLIP_LFLAG; + trace_xfs_attr_set_iter_return(dac->dela_state, args->dp); return -EAGAIN; case XFS_DAS_FLIP_LFLAG: /* @@ -488,6 +497,9 @@ xfs_attr_set_iter( case XFS_DAS_RM_LBLK: if (args->rmtblkno) { error = __xfs_attr_rmtval_remove(dac); + if (error == -EAGAIN) + trace_xfs_attr_set_iter_return( + dac->dela_state, args->dp); if (error) return error; } @@ -545,6 +557,8 @@ xfs_attr_set_iter( if (error) return error; + trace_xfs_attr_set_iter_return( + dac->dela_state, args->dp); return -EAGAIN; } @@ -581,6 +595,7 @@ xfs_attr_set_iter( * series */ dac->dela_state = XFS_DAS_FLIP_NFLAG; + trace_xfs_attr_set_iter_return(dac->dela_state, args->dp); return -EAGAIN; case XFS_DAS_FLIP_NFLAG: @@ -601,6 +616,10 @@ xfs_attr_set_iter( case XFS_DAS_RM_NBLK: if (args->rmtblkno) { error = __xfs_attr_rmtval_remove(dac); + if (error == -EAGAIN) + trace_xfs_attr_set_iter_return( + dac->dela_state, args->dp); + if (error) return error; } @@ -1214,6 +1233,8 @@ xfs_attr_node_addname( * this point. */ dac->flags |= XFS_DAC_DEFER_FINISH; + trace_xfs_attr_node_addname_return( + dac->dela_state, args->dp); return -EAGAIN; } @@ -1394,6 +1415,9 @@ xfs_attr_node_remove_rmt ( * May return -EAGAIN to request that the caller recall this function */ error = __xfs_attr_rmtval_remove(dac); + if (error == -EAGAIN) + trace_xfs_attr_node_remove_rmt_return(dac->dela_state, + dac->da_args->dp); if (error) return error; @@ -1513,6 +1537,8 @@ xfs_attr_node_removename_iter( dac->flags |= XFS_DAC_DEFER_FINISH; dac->dela_state = XFS_DAS_RM_SHRINK; + trace_xfs_attr_node_removename_iter_return( + dac->dela_state, args->dp); return -EAGAIN; } @@ -1531,8 +1557,11 @@ xfs_attr_node_removename_iter( goto out; } - if (error == -EAGAIN) + if (error == -EAGAIN) { + trace_xfs_attr_node_removename_iter_return( + dac->dela_state, args->dp); return error; + } out: if (state) xfs_da_state_free(state); diff --git a/fs/xfs/libxfs/xfs_attr_remote.c b/fs/xfs/libxfs/xfs_attr_remote.c index 6af86bf..b242e1a 100644 --- a/fs/xfs/libxfs/xfs_attr_remote.c +++ b/fs/xfs/libxfs/xfs_attr_remote.c @@ -763,6 +763,7 @@ __xfs_attr_rmtval_remove( */ if (!done) { dac->flags |= XFS_DAC_DEFER_FINISH; + trace_xfs_attr_rmtval_remove_return(dac->dela_state, args->dp); return -EAGAIN; } diff --git a/fs/xfs/xfs_trace.h b/fs/xfs/xfs_trace.h index 363e1bf..7993f55 100644 --- a/fs/xfs/xfs_trace.h +++ b/fs/xfs/xfs_trace.h @@ -3927,6 +3927,31 @@ DEFINE_EVENT(xfs_eofblocks_class, name, \ DEFINE_EOFBLOCKS_EVENT(xfs_ioc_free_eofblocks); DEFINE_EOFBLOCKS_EVENT(xfs_blockgc_free_space); +DECLARE_EVENT_CLASS(xfs_das_state_class, + TP_PROTO(int das, struct xfs_inode *ip), + TP_ARGS(das, ip), + TP_STRUCT__entry( + __field(int, das) + __field(xfs_ino_t, ino) + ), + TP_fast_assign( + __entry->das = das; + __entry->ino = ip->i_ino; + ), + TP_printk("state change %d ino 0x%llx", + __entry->das, __entry->ino) +) + +#define DEFINE_DAS_STATE_EVENT(name) \ +DEFINE_EVENT(xfs_das_state_class, name, \ + TP_PROTO(int das, struct xfs_inode *ip), \ + TP_ARGS(das, ip)) +DEFINE_DAS_STATE_EVENT(xfs_attr_set_fmt_return); +DEFINE_DAS_STATE_EVENT(xfs_attr_set_iter_return); +DEFINE_DAS_STATE_EVENT(xfs_attr_node_addname_return); +DEFINE_DAS_STATE_EVENT(xfs_attr_node_removename_iter_return); +DEFINE_DAS_STATE_EVENT(xfs_attr_node_remove_rmt_return); +DEFINE_DAS_STATE_EVENT(xfs_attr_rmtval_remove_return); #endif /* _TRACE_XFS_H */ #undef TRACE_INCLUDE_PATH -- 2.7.4