From 484507bf20d27afd700d52c67651e6f08d1da1a3 Mon Sep 17 00:00:00 2001
From: Alexey Tikhonov <atikhono@redhat.com>
Date: Wed, 8 Jul 2020 11:34:12 +0200
Subject: [PATCH 35/35] mem-cache: always cleanup old content
(Try to) cleanup old files even if currently mem-cache is disabled.
Reviewed-by: Sumit Bose <sbose@redhat.com>
---
src/responder/nss/nsssrv.c | 98 ++++++++++-----------------
src/responder/nss/nsssrv_mmap_cache.c | 74 ++++++++++++--------
2 files changed, 79 insertions(+), 93 deletions(-)
diff --git a/src/responder/nss/nsssrv.c b/src/responder/nss/nsssrv.c
index 741e94aaa..ffb1ca29d 100644
--- a/src/responder/nss/nsssrv.c
+++ b/src/responder/nss/nsssrv.c
@@ -242,12 +242,6 @@ static int setup_memcaches(struct nss_ctx *nctx)
return ret;
}
- if (memcache_timeout == 0) {
- DEBUG(SSSDBG_CONF_SETTINGS,
- "Fast in-memory cache will not be initialized.");
- return EOK;
- }
-
/* Get all memcache sizes from confdb (pwd, grp, initgr) */
ret = confdb_get_int(nctx->rctx->cdb,
@@ -288,64 +282,40 @@ static int setup_memcaches(struct nss_ctx *nctx)
/* Initialize the fast in-memory caches if they were not disabled */
- if (mc_size_passwd != 0) {
- ret = sss_mmap_cache_init(nctx, "passwd",
- nctx->mc_uid, nctx->mc_gid,
- SSS_MC_PASSWD,
- mc_size_passwd * SSS_MC_CACHE_SLOTS_PER_MB,
- (time_t)memcache_timeout,
- &nctx->pwd_mc_ctx);
- if (ret) {
- DEBUG(SSSDBG_CRIT_FAILURE,
- "Failed to initialize passwd mmap cache: '%s'\n",
- sss_strerror(ret));
- } else {
- DEBUG(SSSDBG_CONF_SETTINGS, "Passwd mmap cache size is %d\n",
- mc_size_passwd);
- }
- } else {
- DEBUG(SSSDBG_IMPORTANT_INFO,
- "Passwd mmap cache is explicitly DISABLED\n");
- }
-
- if (mc_size_group != 0) {
- ret = sss_mmap_cache_init(nctx, "group",
- nctx->mc_uid, nctx->mc_gid,
- SSS_MC_GROUP,
- mc_size_group * SSS_MC_CACHE_SLOTS_PER_MB,
- (time_t)memcache_timeout,
- &nctx->grp_mc_ctx);
- if (ret) {
- DEBUG(SSSDBG_CRIT_FAILURE,
- "Failed to initialize group mmap cache: '%s'\n",
- sss_strerror(ret));
- } else {
- DEBUG(SSSDBG_CONF_SETTINGS, "Group mmap cache size is %d\n",
- mc_size_group);
- }
- } else {
- DEBUG(SSSDBG_IMPORTANT_INFO,
- "Group mmap cache is explicitly DISABLED\n");
- }
-
- if (mc_size_initgroups != 0) {
- ret = sss_mmap_cache_init(nctx, "initgroups",
- nctx->mc_uid, nctx->mc_gid,
- SSS_MC_INITGROUPS,
- mc_size_initgroups * SSS_MC_CACHE_SLOTS_PER_MB,
- (time_t)memcache_timeout,
- &nctx->initgr_mc_ctx);
- if (ret) {
- DEBUG(SSSDBG_CRIT_FAILURE,
- "Failed to initialize initgroups mmap cache: '%s'\n",
- sss_strerror(ret));
- } else {
- DEBUG(SSSDBG_CONF_SETTINGS, "Initgroups mmap cache size is %d\n",
- mc_size_initgroups);
- }
- } else {
- DEBUG(SSSDBG_IMPORTANT_INFO,
- "Initgroups mmap cache is explicitly DISABLED\n");
+ ret = sss_mmap_cache_init(nctx, "passwd",
+ nctx->mc_uid, nctx->mc_gid,
+ SSS_MC_PASSWD,
+ mc_size_passwd * SSS_MC_CACHE_SLOTS_PER_MB,
+ (time_t)memcache_timeout,
+ &nctx->pwd_mc_ctx);
+ if (ret) {
+ DEBUG(SSSDBG_CRIT_FAILURE,
+ "Failed to initialize passwd mmap cache: '%s'\n",
+ sss_strerror(ret));
+ }
+
+ ret = sss_mmap_cache_init(nctx, "group",
+ nctx->mc_uid, nctx->mc_gid,
+ SSS_MC_GROUP,
+ mc_size_group * SSS_MC_CACHE_SLOTS_PER_MB,
+ (time_t)memcache_timeout,
+ &nctx->grp_mc_ctx);
+ if (ret) {
+ DEBUG(SSSDBG_CRIT_FAILURE,
+ "Failed to initialize group mmap cache: '%s'\n",
+ sss_strerror(ret));
+ }
+
+ ret = sss_mmap_cache_init(nctx, "initgroups",
+ nctx->mc_uid, nctx->mc_gid,
+ SSS_MC_INITGROUPS,
+ mc_size_initgroups * SSS_MC_CACHE_SLOTS_PER_MB,
+ (time_t)memcache_timeout,
+ &nctx->initgr_mc_ctx);
+ if (ret) {
+ DEBUG(SSSDBG_CRIT_FAILURE,
+ "Failed to initialize initgroups mmap cache: '%s'\n",
+ sss_strerror(ret));
}
return EOK;
diff --git a/src/responder/nss/nsssrv_mmap_cache.c b/src/responder/nss/nsssrv_mmap_cache.c
index 71919e4ac..f66e76ce4 100644
--- a/src/responder/nss/nsssrv_mmap_cache.c
+++ b/src/responder/nss/nsssrv_mmap_cache.c
@@ -1108,48 +1108,48 @@ static errno_t sss_mc_set_recycled(int fd)
return EOK;
}
-/*
- * When we (re)create a new file we must mark the current file as recycled
- * so active clients will abandon its use ASAP.
- * We unlink the current file and make a new one.
- */
-static errno_t sss_mc_create_file(struct sss_mc_ctx *mc_ctx)
+static void sss_mc_destroy_file(const char *filename)
{
- mode_t old_mask;
+ const useconds_t t = 50000;
+ const int retries = 3;
int ofd;
- int ret, uret;
- useconds_t t = 50000;
- int retries = 3;
+ int ret;
- ofd = open(mc_ctx->file, O_RDWR);
+ ofd = open(filename, O_RDWR);
if (ofd != -1) {
ret = sss_br_lock_file(ofd, 0, 1, retries, t);
if (ret != EOK) {
- DEBUG(SSSDBG_FATAL_FAILURE,
- "Failed to lock file %s.\n", mc_ctx->file);
+ DEBUG(SSSDBG_FATAL_FAILURE, "Failed to lock file %s.\n", filename);
}
ret = sss_mc_set_recycled(ofd);
if (ret) {
DEBUG(SSSDBG_FATAL_FAILURE, "Failed to mark mmap file %s as"
- " recycled: %d(%s)\n",
- mc_ctx->file, ret, strerror(ret));
+ " recycled: %d (%s)\n",
+ filename, ret, strerror(ret));
}
-
close(ofd);
} else if (errno != ENOENT) {
ret = errno;
DEBUG(SSSDBG_CRIT_FAILURE,
- "Failed to open old memory cache file %s: %d(%s).\n",
- mc_ctx->file, ret, strerror(ret));
+ "Failed to open old memory cache file %s: %d (%s)\n",
+ filename, ret, strerror(ret));
}
errno = 0;
- ret = unlink(mc_ctx->file);
+ ret = unlink(filename);
if (ret == -1 && errno != ENOENT) {
ret = errno;
- DEBUG(SSSDBG_TRACE_FUNC, "Failed to rm mmap file %s: %d(%s)\n",
- mc_ctx->file, ret, strerror(ret));
+ DEBUG(SSSDBG_TRACE_FUNC, "Failed to delete mmap file %s: %d (%s)\n",
+ filename, ret, strerror(ret));
}
+}
+
+static errno_t sss_mc_create_file(struct sss_mc_ctx *mc_ctx)
+{
+ const useconds_t t = 50000;
+ const int retries = 3;
+ mode_t old_mask;
+ int ret, uret;
/* temporarily relax umask as we need the file to be readable
* by everyone for now */
@@ -1276,9 +1276,32 @@ errno_t sss_mmap_cache_init(TALLOC_CTX *mem_ctx, const char *name,
struct sss_mc_ctx *mc_ctx = NULL;
int ret, dret;
+ char *filename;
+
+ filename = talloc_asprintf(mem_ctx, "%s/%s", SSS_NSS_MCACHE_DIR, name);
+ if (!filename) {
+ return ENOMEM;
+ }
+ /*
+ * First of all mark the current file as recycled
+ * and unlink so active clients will abandon its use ASAP
+ */
+ sss_mc_destroy_file(filename);
+
+ if ((timeout == 0) || (n_elem == 0)) {
+ DEBUG(SSSDBG_IMPORTANT_INFO,
+ "Fast '%s' mmap cache is explicitly DISABLED\n",
+ mc_type_to_str(type));
+ *mcc = NULL;
+ return EOK;
+ }
+ DEBUG(SSSDBG_CONF_SETTINGS,
+ "Fast '%s' mmap cache: timeout = %d, slots = %zu\n",
+ mc_type_to_str(type), (int)timeout, n_elem);
mc_ctx = talloc_zero(mem_ctx, struct sss_mc_ctx);
if (!mc_ctx) {
+ talloc_free(filename);
return ENOMEM;
}
mc_ctx->fd = -1;
@@ -1297,12 +1320,7 @@ errno_t sss_mmap_cache_init(TALLOC_CTX *mem_ctx, const char *name,
mc_ctx->valid_time_slot = timeout;
- mc_ctx->file = talloc_asprintf(mc_ctx, "%s/%s",
- SSS_NSS_MCACHE_DIR, name);
- if (!mc_ctx->file) {
- ret = ENOMEM;
- goto done;
- }
+ mc_ctx->file = talloc_steal(mc_ctx, filename);
/* elements must always be multiple of 8 to make things easier to handle,
* so we increase by the necessary amount if they are not a multiple */
@@ -1320,8 +1338,6 @@ errno_t sss_mmap_cache_init(TALLOC_CTX *mem_ctx, const char *name,
MC_ALIGN64(mc_ctx->ht_size);
- /* for now ALWAYS create a new file on restart */
-
ret = sss_mc_create_file(mc_ctx);
if (ret) {
goto done;
--
2.21.3