Re: [PATCH 35/45] xfs: introduce per-cpu CIL tracking sructure
From: Dave Chinner <david@fromorbit.com>
Date: 2021-03-11 06:43:28
On Thu, Mar 11, 2021 at 05:33:38PM +1100, Dave Chinner wrote:
On Wed, Mar 10, 2021 at 04:11:43PM -0800, Darrick J. Wong wrote:quoted
On Fri, Mar 05, 2021 at 04:11:33PM +1100, Dave Chinner wrote:quoted
From: Dave Chinner <redacted> The CIL push lock is highly contended on larger machines, becoming a hard bottleneck that about 700,000 transaction commits/s on >16p machines. To address this, start moving the CIL tracking infrastructure to utilise per-CPU structures. We need to track the space used, the amount of log reservation space reserved to write the CIL, the log items in the CIL and the busy extents that need to be completed by the CIL commit. This requires a couple of per-cpu counters, an unordered per-cpu list and a globally ordered per-cpu list. Create a per-cpu structure to hold these and all the management interfaces needed, as well as the hooks to handle hotplug CPUs. Signed-off-by: Dave Chinner <redacted> --- fs/xfs/xfs_log_cil.c | 94 ++++++++++++++++++++++++++++++++++++++ fs/xfs/xfs_log_priv.h | 15 ++++++ include/linux/cpuhotplug.h | 1 + 3 files changed, 110 insertions(+)diff --git a/fs/xfs/xfs_log_cil.c b/fs/xfs/xfs_log_cil.c index f8fb2f59e24c..1bcf0d423d30 100644 --- a/fs/xfs/xfs_log_cil.c +++ b/fs/xfs/xfs_log_cil.c@@ -1365,6 +1365,93 @@ xfs_log_item_in_current_chkpt( return true; } +#ifdef CONFIG_HOTPLUG_CPU +static LIST_HEAD(xlog_cil_pcp_list); +static DEFINE_SPINLOCK(xlog_cil_pcp_lock); +static bool xlog_cil_pcp_init; + +static int +xlog_cil_pcp_dead( + unsigned int cpu) +{ + struct xfs_cil *cil; + + spin_lock(&xlog_cil_pcp_lock); + list_for_each_entry(cil, &xlog_cil_pcp_list, xc_pcp_list) {Weird indentation.quoted
+ /* move stuff on dead CPU to context */Should this have some actual code? I don't think any of the remaining patches add anything here.They should be moving stuff to the current CIL ctx so it is captured when the CPU goes down.
Yup, looks like I missed updating this. Will add it in the patches that need it. -Dave. -- Dave Chinner david@fromorbit.com