The following pull request was submitted through Github. It can be accessed and reviewed at: https://github.com/lxc/lxcfs/pull/418
This e-mail was sent by the LXC bot, direct replies will not reach the author unless they happen to be subscribed to this list. === Description (from pull-request) === …unting Link: https://discuss.linuxcontainers.org/t/invalid-swaptotal-in-proc-meminfo-swaptotal-0 Signed-off-by: Christian Brauner <christian.brau...@ubuntu.com>
From c68050167a14b3ed5cc0c681f5526f10b624fbcf Mon Sep 17 00:00:00 2001 From: Christian Brauner <christian.brau...@ubuntu.com> Date: Wed, 24 Jun 2020 13:13:25 +0200 Subject: [PATCH] proc_fuse: provide host values when kernel does not support swap accounting Link: https://discuss.linuxcontainers.org/t/invalid-swaptotal-in-proc-meminfo-swaptotal-0 Signed-off-by: Christian Brauner <christian.brau...@ubuntu.com> --- src/bindings.c | 12 ++++++++++++ src/bindings.h | 1 + src/cgroups/cgfsng.c | 31 +++++++++++++++++++++++++++++++ src/cgroups/cgroup.h | 1 + src/proc_fuse.c | 4 ++-- 5 files changed, 47 insertions(+), 2 deletions(-) diff --git a/src/bindings.c b/src/bindings.c index 28da74b..8dc885d 100644 --- a/src/bindings.c +++ b/src/bindings.c @@ -50,6 +50,7 @@ #include "utils.h" static bool can_use_pidfd; +static bool can_use_swap; static volatile sig_atomic_t reload_successful; @@ -58,6 +59,11 @@ bool liblxcfs_functional(void) return reload_successful != 0; } +bool liblxcfs_can_use_swap(void) +{ + return can_use_swap; +} + /* Define pivot_root() if missing from the C library */ #ifndef HAVE_PIVOT_ROOT static int pivot_root(const char *new_root, const char *put_old) @@ -880,6 +886,12 @@ static void __attribute__((constructor)) lxcfs_init(void) lxcfs_info("Kernel supports pidfds"); } + can_use_swap = cgroup_ops->can_use_swap(cgroup_ops); + if (can_use_swap) + lxcfs_info("Kernel supports swap accounting"); + else + lxcfs_info("Kernel does not support swap accounting"); + lxcfs_info("api_extensions:"); for (i = 0; i < nr_api_extensions; i++) lxcfs_info("- %s", api_extensions[i]); diff --git a/src/bindings.h b/src/bindings.h index 28543dc..4ab4f72 100644 --- a/src/bindings.h +++ b/src/bindings.h @@ -91,6 +91,7 @@ extern pid_t lookup_initpid_in_store(pid_t qpid); extern void prune_init_slice(char *cg); extern bool supports_pidfd(void); extern bool liblxcfs_functional(void); +extern bool liblxcfs_can_use_swap(void); static inline int install_signal_handler(int signo, void (*handler)(int, siginfo_t *, void *)) diff --git a/src/cgroups/cgfsng.c b/src/cgroups/cgfsng.c index 89f7cab..cf891b3 100644 --- a/src/cgroups/cgfsng.c +++ b/src/cgroups/cgfsng.c @@ -619,6 +619,36 @@ static int cgfsng_get_memory_swap_max(struct cgroup_ops *ops, return cgfsng_get_memory(ops, cgroup, "memory.swap.max", value); } +static bool cgfsng_can_use_swap(struct cgroup_ops *ops) +{ + bool has_swap = false; + struct hierarchy *h; + + h = ops->get_hierarchy(ops, "memory"); + if (!h) + return false; + + if (is_unified_hierarchy(h)) { + if (faccessat(h->fd, "memory.swap.max", F_OK, 0)) + return false; + + if (faccessat(h->fd, "memory.swap.current", F_OK, 0)) + return false; + + has_swap = true; + } else { + if (faccessat(h->fd, "memory.memsw.limit_in_bytes", F_OK, 0)) + return false; + + if (faccessat(h->fd, "memory.memsw.usage_in_bytes", F_OK, 0)) + return false; + + has_swap = true; + } + + return has_swap; +} + static int cgfsng_get_memory_stats(struct cgroup_ops *ops, const char *cgroup, char **value) { @@ -977,6 +1007,7 @@ struct cgroup_ops *cgfsng_ops_init(void) cgfsng_ops->get_memory_swap_max = cgfsng_get_memory_swap_max; cgfsng_ops->get_memory_current = cgfsng_get_memory_current; cgfsng_ops->get_memory_swap_current = cgfsng_get_memory_swap_current; + cgfsng_ops->can_use_swap = cgfsng_can_use_swap; /* cpuset */ cgfsng_ops->get_cpuset_cpus = cgfsng_get_cpuset_cpus; diff --git a/src/cgroups/cgroup.h b/src/cgroups/cgroup.h index e8327fd..ad4a3ae 100644 --- a/src/cgroups/cgroup.h +++ b/src/cgroups/cgroup.h @@ -153,6 +153,7 @@ struct cgroup_ops { char **value); int (*get_memory_swap_max)(struct cgroup_ops *ops, const char *cgroup, char **value); + bool (*can_use_swap)(struct cgroup_ops *ops); /* cpuset */ int (*get_cpuset_cpus)(struct cgroup_ops *ops, const char *cgroup, diff --git a/src/proc_fuse.c b/src/proc_fuse.c index c78b9e8..21bed1e 100644 --- a/src/proc_fuse.c +++ b/src/proc_fuse.c @@ -248,7 +248,7 @@ static int proc_swaps_read(char *buf, size_t size, off_t offset, *memswusage_str = NULL; struct fuse_context *fc = fuse_get_context(); struct lxcfs_opts *opts = (struct lxcfs_opts *)fuse_get_context()->private_data; - bool wants_swap = opts && !opts->swap_off; + bool wants_swap = opts && !opts->swap_off && liblxcfs_can_use_swap(); struct file_info *d = INTTYPE_TO_PTR(fi->fh); uint64_t memswlimit = 0, memlimit = 0, memusage = 0, memswusage = 0, swtotal = 0, swfree = 0, swusage = 0; @@ -1021,7 +1021,7 @@ static int proc_meminfo_read(char *buf, size_t size, off_t offset, __do_fclose FILE *f = NULL; struct fuse_context *fc = fuse_get_context(); struct lxcfs_opts *opts = (struct lxcfs_opts *)fuse_get_context()->private_data; - bool wants_swap = opts && !opts->swap_off, host_swap = false; + bool wants_swap = opts && !opts->swap_off && liblxcfs_can_use_swap(), host_swap = false; struct file_info *d = INTTYPE_TO_PTR(fi->fh); uint64_t memlimit = 0, memusage = 0, memswlimit = 0, memswusage = 0, hosttotal = 0, swfree = 0, swusage = 0, swtotal = 0;
_______________________________________________ lxc-devel mailing list lxc-devel@lists.linuxcontainers.org http://lists.linuxcontainers.org/listinfo/lxc-devel
