linux-kernel - Re: [PATCH v2 7/7] cxl/region: Drop goto pattern of construct

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <67b67f9d670d1_2d1e2947@dwillia2-xfh.jf.intel.com.notmuch>
Date: Wed, 19 Feb 2025 17:04:29 -0800
From: Dan Williams <dan.j.williams@...el.com>
To: Li Ming <ming.li@...omail.com>, <dave@...olabs.net>,
	<jonathan.cameron@...wei.com>, <dave.jiang@...el.com>,
	<alison.schofield@...el.com>, <vishal.l.verma@...el.com>,
	<ira.weiny@...el.com>, <dan.j.williams@...el.com>
CC: <linux-cxl@...r.kernel.org>, <linux-kernel@...r.kernel.org>, Li Ming
	<ming.li@...omail.com>
Subject: Re: [PATCH v2 7/7] cxl/region: Drop goto pattern of
 construct_region()

Li Ming wrote:
> Some operations need to be protected by the cxl_region_rwsem in
> construct_region(). Currently, construct_region() uses down_write() and
> up_write() for the cxl_region_rwsem locking, so there is a goto pattern
> after down_write() invoked to release cxl_region_rwsem.
> 
> construct region() can be optimized to remove the goto pattern. The
> changes are creating a new function called construct_auto_region() which
> will include all checking and operations protected by the
> cxl_region_rwsem, and using guard(rwsem_write) to replace down_write()
> and up_write() in construct_auto_region().
> 
> Signed-off-by: Li Ming <ming.li@...omail.com>
> ---
> v2:
> - Rename __construct_region() to construct_auto_region(). (Jonathan and Dave)
> ---
>  drivers/cxl/core/region.c | 71 +++++++++++++++++++++------------------
>  1 file changed, 39 insertions(+), 32 deletions(-)
> 
> diff --git a/drivers/cxl/core/region.c b/drivers/cxl/core/region.c
> index 320a3f218131..7a9e51aba9f4 100644
> --- a/drivers/cxl/core/region.c
> +++ b/drivers/cxl/core/region.c
> @@ -3216,49 +3216,31 @@ static int match_region_by_range(struct device *dev, const void *data)
>  	return 0;
>  }
>  
> -/* Establish an empty region covering the given HPA range */
> -static struct cxl_region *construct_region(struct cxl_root_decoder *cxlrd,
> -					   struct cxl_endpoint_decoder *cxled)
> +static int construct_auto_region(struct cxl_region *cxlr,

...probably would have called this __construct_region() since there is
little distinction that merits adding the "auto" qualifier.

Other than that, for this and the others you can add:

Reviewed-by: Dan Williams <dan.j.williams@...el.com>