From f1d13cacabe140305844879e495ca67837e059cc Mon Sep 17 00:00:00 2001 From: SeongJae Park Date: Tue, 1 Nov 2022 22:03:24 +0000 Subject: mm/damon/sysfs: implement DAMOS tried regions update command Implement the code for filling the data of 'tried_regions' DAMON sysfs directory. With this commit, DAMON sysfs interface users can write a special keyword, 'update_schemes_tried_regions' to the corresponding 'state' file of the kdamond. Then, DAMON sysfs interface will collect the tried regions information using the 'before_damos_apply()' callback for one aggregation interval and populate scheme region directories with the values. [sj@kernel.org: skip tried regions update if the scheme directory was removed] Link: https://lkml.kernel.org/r/20221114182954.4745-2-sj@kernel.org Link: https://lkml.kernel.org/r/20221101220328.95765-5-sj@kernel.org Signed-off-by: SeongJae Park Cc: Jonathan Corbet Cc: Shuah Khan Signed-off-by: Andrew Morton --- mm/damon/sysfs-common.h | 6 ++++ mm/damon/sysfs-schemes.c | 80 ++++++++++++++++++++++++++++++++++++++++++++++++ mm/damon/sysfs.c | 57 ++++++++++++++++++++++++++++++++-- 3 files changed, 141 insertions(+), 2 deletions(-) (limited to 'mm/damon') diff --git a/mm/damon/sysfs-common.h b/mm/damon/sysfs-common.h index 4626b2784404..634a6e7fca78 100644 --- a/mm/damon/sysfs-common.h +++ b/mm/damon/sysfs-common.h @@ -44,3 +44,9 @@ int damon_sysfs_set_schemes(struct damon_ctx *ctx, void damon_sysfs_schemes_update_stats( struct damon_sysfs_schemes *sysfs_schemes, struct damon_ctx *ctx); + +int damon_sysfs_schemes_update_regions_start( + struct damon_sysfs_schemes *sysfs_schemes, + struct damon_ctx *ctx); + +int damon_sysfs_schemes_update_regions_stop(struct damon_ctx *ctx); diff --git a/mm/damon/sysfs-schemes.c b/mm/damon/sysfs-schemes.c index f0b5ad7e721d..5f14f18bcc49 100644 --- a/mm/damon/sysfs-schemes.c +++ b/mm/damon/sysfs-schemes.c @@ -1244,3 +1244,83 @@ void damon_sysfs_schemes_update_stats( sysfs_stats->qt_exceeds = scheme->stat.qt_exceeds; } } + +/* + * damon_sysfs_schemes that need to update its schemes regions dir. Protected + * by damon_sysfs_lock + */ +static struct damon_sysfs_schemes *damon_sysfs_schemes_for_damos_callback; +static int damon_sysfs_schemes_region_idx; + +/* + * DAMON callback that called before damos apply. While this callback is + * registered, damon_sysfs_lock should be held to ensure the regions + * directories exist. + */ +static int damon_sysfs_before_damos_apply(struct damon_ctx *ctx, + struct damon_target *t, struct damon_region *r, + struct damos *s) +{ + struct damos *scheme; + struct damon_sysfs_scheme_regions *sysfs_regions; + struct damon_sysfs_scheme_region *region; + struct damon_sysfs_schemes *sysfs_schemes = + damon_sysfs_schemes_for_damos_callback; + int schemes_idx = 0; + + damon_for_each_scheme(scheme, ctx) { + if (scheme == s) + break; + schemes_idx++; + } + + /* user could have removed the scheme sysfs dir */ + if (schemes_idx >= sysfs_schemes->nr) + return 0; + + sysfs_regions = sysfs_schemes->schemes_arr[schemes_idx]->tried_regions; + region = damon_sysfs_scheme_region_alloc(r); + list_add_tail(®ion->list, &sysfs_regions->regions_list); + sysfs_regions->nr_regions++; + if (kobject_init_and_add(®ion->kobj, + &damon_sysfs_scheme_region_ktype, + &sysfs_regions->kobj, "%d", + damon_sysfs_schemes_region_idx++)) { + kobject_put(®ion->kobj); + } + return 0; +} + +/* Called from damon_sysfs_cmd_request_callback under damon_sysfs_lock */ +int damon_sysfs_schemes_update_regions_start( + struct damon_sysfs_schemes *sysfs_schemes, + struct damon_ctx *ctx) +{ + struct damos *scheme; + int schemes_idx = 0; + + damon_for_each_scheme(scheme, ctx) { + struct damon_sysfs_scheme *sysfs_scheme; + + sysfs_scheme = sysfs_schemes->schemes_arr[schemes_idx++]; + damon_sysfs_scheme_regions_rm_dirs( + sysfs_scheme->tried_regions); + } + + damon_sysfs_schemes_for_damos_callback = sysfs_schemes; + ctx->callback.before_damos_apply = damon_sysfs_before_damos_apply; + return 0; +} + +/* + * Called from damon_sysfs_cmd_request_callback under damon_sysfs_lock. Caller + * should unlock damon_sysfs_lock which held before + * damon_sysfs_schemes_update_regions_start() + */ +int damon_sysfs_schemes_update_regions_stop(struct damon_ctx *ctx) +{ + damon_sysfs_schemes_for_damos_callback = NULL; + ctx->callback.before_damos_apply = NULL; + damon_sysfs_schemes_region_idx = 0; + return 0; +} diff --git a/mm/damon/sysfs.c b/mm/damon/sysfs.c index 284daf274b3e..ffb5a84059d7 100644 --- a/mm/damon/sysfs.c +++ b/mm/damon/sysfs.c @@ -999,6 +999,11 @@ enum damon_sysfs_cmd { * files. */ DAMON_SYSFS_CMD_UPDATE_SCHEMES_STATS, + /* + * @DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: Update schemes tried + * regions + */ + DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS, /* * @NR_DAMON_SYSFS_CMDS: Total number of DAMON sysfs commands. */ @@ -1011,6 +1016,7 @@ static const char * const damon_sysfs_cmd_strs[] = { "off", "commit", "update_schemes_stats", + "update_schemes_tried_regions", }; /* @@ -1193,6 +1199,16 @@ static int damon_sysfs_set_targets(struct damon_ctx *ctx, static void damon_sysfs_before_terminate(struct damon_ctx *ctx) { struct damon_target *t, *next; + struct damon_sysfs_kdamond *kdamond; + + /* damon_sysfs_schemes_update_regions_stop() might not yet called */ + kdamond = damon_sysfs_cmd_request.kdamond; + if (kdamond && damon_sysfs_cmd_request.cmd == + DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS && + ctx == kdamond->damon_ctx) { + damon_sysfs_schemes_update_regions_stop(ctx); + mutex_unlock(&damon_sysfs_lock); + } if (!damon_target_has_pid(ctx)) return; @@ -1225,6 +1241,27 @@ static int damon_sysfs_upd_schemes_stats(struct damon_sysfs_kdamond *kdamond) return 0; } +static int damon_sysfs_upd_schemes_regions_start( + struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx = kdamond->damon_ctx; + + if (!ctx) + return -EINVAL; + return damon_sysfs_schemes_update_regions_start( + kdamond->contexts->contexts_arr[0]->schemes, ctx); +} + +static int damon_sysfs_upd_schemes_regions_stop( + struct damon_sysfs_kdamond *kdamond) +{ + struct damon_ctx *ctx = kdamond->damon_ctx; + + if (!ctx) + return -EINVAL; + return damon_sysfs_schemes_update_regions_stop(ctx); +} + static inline bool damon_sysfs_kdamond_running( struct damon_sysfs_kdamond *kdamond) { @@ -1277,10 +1314,12 @@ static int damon_sysfs_commit_input(struct damon_sysfs_kdamond *kdamond) static int damon_sysfs_cmd_request_callback(struct damon_ctx *c) { struct damon_sysfs_kdamond *kdamond; + static bool damon_sysfs_schemes_regions_updating; int err = 0; /* avoid deadlock due to concurrent state_store('off') */ - if (!mutex_trylock(&damon_sysfs_lock)) + if (!damon_sysfs_schemes_regions_updating && + !mutex_trylock(&damon_sysfs_lock)) return 0; kdamond = damon_sysfs_cmd_request.kdamond; if (!kdamond || kdamond->damon_ctx != c) @@ -1292,13 +1331,27 @@ static int damon_sysfs_cmd_request_callback(struct damon_ctx *c) case DAMON_SYSFS_CMD_COMMIT: err = damon_sysfs_commit_input(kdamond); break; + case DAMON_SYSFS_CMD_UPDATE_SCHEMES_TRIED_REGIONS: + if (!damon_sysfs_schemes_regions_updating) { + err = damon_sysfs_upd_schemes_regions_start(kdamond); + if (!err) { + damon_sysfs_schemes_regions_updating = true; + goto keep_lock_out; + } + } else { + err = damon_sysfs_upd_schemes_regions_stop(kdamond); + damon_sysfs_schemes_regions_updating = false; + } + break; default: break; } /* Mark the request as invalid now. */ damon_sysfs_cmd_request.kdamond = NULL; out: - mutex_unlock(&damon_sysfs_lock); + if (!damon_sysfs_schemes_regions_updating) + mutex_unlock(&damon_sysfs_lock); +keep_lock_out: return err; } -- cgit v1.2.3