Re: [RFC v5 PATCH 8/9] xfs: create an error tag for random relog reservation

From: Allison Collins <allison.henderson@oracle.com>
To: Brian Foster <bfoster@redhat.com>, linux-xfs@vger.kernel.org
Subject: Re: [RFC v5 PATCH 8/9] xfs: create an error tag for random relog reservation
Date: Thu, 27 Feb 2020 16:35:58 -0700	[thread overview]
Message-ID: <357287c8-420f-b854-33ae-c716eb6c138b@oracle.com> (raw)
In-Reply-To: <20200227134321.7238-9-bfoster@redhat.com>

On 2/27/20 6:43 AM, Brian Foster wrote:
> Create an errortag to randomly enable relogging on permanent
> transactions. This only stresses relog reservation management and
> does not enable relogging of any particular items. The tag will be
> reused in a subsequent patch to enable random item relogging.
> 
> Signed-off-by: Brian Foster <bfoster@redhat.com>
Alrighty, looks ok:
Reviewed-by: Allison Collins <allison.henderson@oracle.com>

> ---
>   fs/xfs/libxfs/xfs_errortag.h | 4 +++-
>   fs/xfs/xfs_error.c           | 3 +++
>   fs/xfs/xfs_trans.c           | 6 ++++++
>   3 files changed, 12 insertions(+), 1 deletion(-)
> 
> diff --git a/fs/xfs/libxfs/xfs_errortag.h b/fs/xfs/libxfs/xfs_errortag.h
> index 79e6c4fb1d8a..ca7bcadb9455 100644
> --- a/fs/xfs/libxfs/xfs_errortag.h
> +++ b/fs/xfs/libxfs/xfs_errortag.h
> @@ -55,7 +55,8 @@
>   #define XFS_ERRTAG_FORCE_SCRUB_REPAIR			32
>   #define XFS_ERRTAG_FORCE_SUMMARY_RECALC			33
>   #define XFS_ERRTAG_IUNLINK_FALLBACK			34
> -#define XFS_ERRTAG_MAX					35
> +#define XFS_ERRTAG_RELOG				35
> +#define XFS_ERRTAG_MAX					36
>   
>   /*
>    * Random factors for above tags, 1 means always, 2 means 1/2 time, etc.
> @@ -95,5 +96,6 @@
>   #define XFS_RANDOM_FORCE_SCRUB_REPAIR			1
>   #define XFS_RANDOM_FORCE_SUMMARY_RECALC			1
>   #define XFS_RANDOM_IUNLINK_FALLBACK			(XFS_RANDOM_DEFAULT/10)
> +#define XFS_RANDOM_RELOG				XFS_RANDOM_DEFAULT
>   
>   #endif /* __XFS_ERRORTAG_H_ */
> diff --git a/fs/xfs/xfs_error.c b/fs/xfs/xfs_error.c
> index 331765afc53e..2838b909287e 100644
> --- a/fs/xfs/xfs_error.c
> +++ b/fs/xfs/xfs_error.c
> @@ -53,6 +53,7 @@ static unsigned int xfs_errortag_random_default[] = {
>   	XFS_RANDOM_FORCE_SCRUB_REPAIR,
>   	XFS_RANDOM_FORCE_SUMMARY_RECALC,
>   	XFS_RANDOM_IUNLINK_FALLBACK,
> +	XFS_RANDOM_RELOG,
>   };
>   
>   struct xfs_errortag_attr {
> @@ -162,6 +163,7 @@ XFS_ERRORTAG_ATTR_RW(buf_lru_ref,	XFS_ERRTAG_BUF_LRU_REF);
>   XFS_ERRORTAG_ATTR_RW(force_repair,	XFS_ERRTAG_FORCE_SCRUB_REPAIR);
>   XFS_ERRORTAG_ATTR_RW(bad_summary,	XFS_ERRTAG_FORCE_SUMMARY_RECALC);
>   XFS_ERRORTAG_ATTR_RW(iunlink_fallback,	XFS_ERRTAG_IUNLINK_FALLBACK);
> +XFS_ERRORTAG_ATTR_RW(relog,		XFS_ERRTAG_RELOG);
>   
>   static struct attribute *xfs_errortag_attrs[] = {
>   	XFS_ERRORTAG_ATTR_LIST(noerror),
> @@ -199,6 +201,7 @@ static struct attribute *xfs_errortag_attrs[] = {
>   	XFS_ERRORTAG_ATTR_LIST(force_repair),
>   	XFS_ERRORTAG_ATTR_LIST(bad_summary),
>   	XFS_ERRORTAG_ATTR_LIST(iunlink_fallback),
> +	XFS_ERRORTAG_ATTR_LIST(relog),
>   	NULL,
>   };
>   
> diff --git a/fs/xfs/xfs_trans.c b/fs/xfs/xfs_trans.c
> index f7f2411ead4e..24e0208b74b8 100644
> --- a/fs/xfs/xfs_trans.c
> +++ b/fs/xfs/xfs_trans.c
> @@ -19,6 +19,7 @@
>   #include "xfs_trace.h"
>   #include "xfs_error.h"
>   #include "xfs_defer.h"
> +#include "xfs_errortag.h"
>   
>   kmem_zone_t	*xfs_trans_zone;
>   
> @@ -263,6 +264,11 @@ xfs_trans_alloc(
>   	struct xfs_trans	*tp;
>   	int			error;
>   
> +	/* relogging requires permanent transactions */
> +	if (XFS_TEST_ERROR(false, mp, XFS_ERRTAG_RELOG) &&
> +	    resp->tr_logflags & XFS_TRANS_PERM_LOG_RES)
> +		flags |= XFS_TRANS_RELOG;
> +
>   	/*
>   	 * Allocate the handle before we do our freeze accounting and setting up
>   	 * GFP_NOFS allocation context so that we avoid lockdep false positives
>