From ab71d2d301211a45420b1fb085072c79ea6a8027 Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Wed, 5 Mar 2025 14:27:26 -0800 Subject: [PATCH] mm/damon/sysfs-schemes: let damon_sysfs_scheme_set_filters() be used for different named directories Patch series "mm/damon: add sysfs dirs for managing DAMOS filters based on handling layers". DAMOS filters are categorized into two groups based on their handling layers, namely core and operations layers. The categorization affects when each filter is evaluated. Core layer handled filters are evaluated first. The order meant nothing before, but introduction of allow filters changed that. DAMOS sysfs interface provides single directory for filters, namely 'filters'. Users can install any filters in any order there. DAMON will internally categorize those into core and operations layer handled ones, and apply the evaluation order rule. The ordering rule is clearly documented. But the interface could still confuse users since it is allowed to install filters on the directory in mixed ways. Add two sysfs directories for managing filters by handling layers, namely 'core_filters' and 'ops_filters' for filters that handled by core and operations layer, respectively. Those are avoided to be used for installing filters that not handled by the assumed layers. For backward compatibility, keep 'filters' directory with its curernt behavior. Filters installed in the directory will be added to DAMON after those of 'core_filters' and 'ops_filters' directories, with the automatic categorizations. Also recommend users to use the new directories while noticing 'filters' directory could be deprecated in future on the usage documents. Note that new directories provide all features that were provided with 'filters', but just in a more clear way. Deprecating 'filters' in future will hence not make an irreversal feature loss. This patch (of 8): damon_sysfs_scheme_set_filters() is using a hard-coded directory name, "filters". Refactor for general named directories of same files hierarchy, to use from upcoming changes for adding sibling directories having files same to those of "filters", and named as "core_filters" and "ops_filters". [arnd@arndb.deL avoid Wformat-security warning] Link: https://lkml.kernel.org/r/20250310135142.4176976-1-arnd@kernel.org Link: https://lkml.kernel.org/r/20250305222733.59089-1-sj@kernel.org Link: https://lkml.kernel.org/r/20250305222733.59089-2-sj@kernel.org Signed-off-by: SeongJae Park Signed-off-by: Arnd Bergmann Cc: Jonathan Corbet Signed-off-by: Andrew Morton --- mm/damon/sysfs-schemes.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c index 66a1c46cee847..d769b24f90a40 100644 --- a/mm/damon/sysfs-schemes.c +++ b/mm/damon/sysfs-schemes.c @@ -1604,7 +1604,9 @@ static int damon_sysfs_scheme_set_watermarks(struct damon_sysfs_scheme *scheme) return err; } -static int damon_sysfs_scheme_set_filters(struct damon_sysfs_scheme *scheme) +static int damon_sysfs_scheme_set_filters(struct damon_sysfs_scheme *scheme, + const char *name, + struct damon_sysfs_scheme_filters **filters_ptr) { struct damon_sysfs_scheme_filters *filters = damon_sysfs_scheme_filters_alloc(); @@ -1614,11 +1616,11 @@ static int damon_sysfs_scheme_set_filters(struct damon_sysfs_scheme *scheme) return -ENOMEM; err = kobject_init_and_add(&filters->kobj, &damon_sysfs_scheme_filters_ktype, &scheme->kobj, - "filters"); + "%s", name); if (err) kobject_put(&filters->kobj); else - scheme->filters = filters; + *filters_ptr = filters; return err; } @@ -1670,7 +1672,8 @@ static int damon_sysfs_scheme_add_dirs(struct damon_sysfs_scheme *scheme) err = damon_sysfs_scheme_set_watermarks(scheme); if (err) goto put_quotas_access_pattern_out; - err = damon_sysfs_scheme_set_filters(scheme); + err = damon_sysfs_scheme_set_filters(scheme, "filters", + &scheme->filters); if (err) goto put_watermarks_quotas_access_pattern_out; err = damon_sysfs_scheme_set_stats(scheme); -- 2.50.1