make meminfo and swaps cgroupv2 aware

and deduplicate the corresponding code

Signed-off-by: Wolfgang Bumiller <w.bumiller@proxmox.com>

diff --git a/src/bindings.c b/src/bindings.c
index eb62ddbdbc656686aec33735056a4b131bd45c69..e417a13a3558bf795f6c1096c2546b897feea1dd 100644 (file)
--- a/src/bindings.c
+++ b/src/bindings.c
@@ -44,6 +44,7 @@ static bool can_use_pidfd;
 static bool can_use_swap;
 static bool can_use_sys_cpu;
 static bool has_versioned_opts;
+static bool memory_is_cgroupv2;
 
 static volatile sig_atomic_t reload_successful;
 
@@ -67,6 +68,11 @@ bool liblxcfs_has_versioned_opts(void)
        return has_versioned_opts;
 }
 
+bool liblxcfs_memory_is_cgroupv2(void)
+{
+       return memory_is_cgroupv2;
+}
+
 /* 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)
@@ -837,6 +843,7 @@ static void __attribute__((constructor)) lxcfs_init(void)
                                  pidfd = -EBADF;
        int i = 0;
        pid_t pid;
+       struct hierarchy *hierarchy;
 
        lxcfs_info("Running constructor %s to reload liblxcfs", __func__);
 
@@ -894,6 +901,9 @@ static void __attribute__((constructor)) lxcfs_init(void)
        else
                lxcfs_info("Kernel does not support swap accounting");
 
+       hierarchy = cgroup_ops->get_hierarchy(cgroup_ops, "memory");
+       memory_is_cgroupv2 = hierarchy && is_unified_hierarchy(hierarchy);
+
        lxcfs_info("api_extensions:");
        for (size_t nr = 0; nr < nr_api_extensions; nr++)
                lxcfs_info("- %s", api_extensions[nr]);

diff --git a/src/bindings.h b/src/bindings.h
index a278aa7a6899a9530b85ff086ac21ca18675de07..e35423ac5da32fce9cbca29758232b0b05383a08 100644 (file)
--- a/src/bindings.h
+++ b/src/bindings.h
@@ -104,6 +104,7 @@ extern void prune_init_slice(char *cg);
 extern bool supports_pidfd(void);
 extern bool liblxcfs_functional(void);
 extern bool liblxcfs_can_use_swap(void);
+extern bool liblxcfs_memory_is_cgroupv2(void);
 extern bool liblxcfs_can_use_sys_cpu(void);
 extern bool liblxcfs_has_versioned_opts(void);
 

diff --git a/src/proc_fuse.c b/src/proc_fuse.c
index 4ac5d44b0a10c32033044f89627e3b303a8d51b4..c9103771dca4be4cf218604bcdc0a9a4395c01e0 100644 (file)
--- a/src/proc_fuse.c
+++ b/src/proc_fuse.c
@@ -303,6 +303,43 @@ static inline bool startswith(const char *line, const char *pref)
        return strncmp(line, pref, strlen(pref)) == 0;
 }
 
+static void get_swap_info(const char *cgroup, uint64_t memlimit,
+                         uint64_t memusage, uint64_t *swtotal,
+                         uint64_t *swusage, uint64_t *memswpriority)
+{
+       __do_free char *memswusage_str = NULL, *memswpriority_str = NULL;
+       size_t memswlimit = 0, memswusage = 0;
+       int ret;
+
+       *swtotal = *swusage = 0;
+       *memswpriority = 1;
+
+       memswlimit = get_min_memlimit(cgroup, true);
+       if (memswlimit > 0) {
+               ret = cgroup_ops->get_memory_swap_current(cgroup_ops, cgroup, &memswusage_str);
+               if (ret < 0 || safe_uint64(memswusage_str, &memswusage, 10) != 0)
+                       return;
+
+               if (liblxcfs_memory_is_cgroupv2()) {
+                       *swtotal = memswlimit / 1024;
+                       *swusage = memswusage / 1024;
+               } else {
+                       if (memlimit > memswlimit)
+                               *swtotal = 0;
+                       else
+                               *swtotal = (memswlimit - memlimit) / 1024;
+                       if (memusage > memswusage || swtotal == 0)
+                               *swusage = 0;
+                       else
+                               *swusage = (memswusage - memusage) / 1024;
+               }
+
+               ret = cgroup_ops->get_memory_swappiness(cgroup_ops, cgroup, &memswpriority_str);
+               if (ret >= 0)
+                       safe_uint64(memswpriority_str, memswpriority, 10);
+       }
+}
+
 static int proc_swaps_read(char *buf, size_t size, off_t offset,
                           struct fuse_file_info *fi)
 {
@@ -311,7 +348,7 @@ static int proc_swaps_read(char *buf, size_t size, off_t offset,
        struct fuse_context *fc = fuse_get_context();
        bool wants_swap = lxcfs_has_opt(fuse_get_context()->private_data, LXCFS_SWAP_ON);
        struct file_info *d = INTTYPE_TO_PTR(fi->fh);
-       uint64_t memswlimit = 0, memlimit = 0, memusage = 0, memswusage = 0,
+       uint64_t memlimit = 0, memusage = 0,
                 swtotal = 0, swusage = 0, memswpriority = 1,
                 hostswtotal = 0, hostswfree = 0;
        ssize_t total_len = 0;
@@ -357,26 +394,8 @@ static int proc_swaps_read(char *buf, size_t size, off_t offset,
        if (safe_uint64(memusage_str, &memusage, 10) < 0)
                lxcfs_error("Failed to convert memusage %s", memusage_str);
 
-       if (wants_swap) {
-               memswlimit = get_min_memlimit(cgroup, true);
-               if (memswlimit > 0) {
-                       ret = cgroup_ops->get_memory_swap_current(cgroup_ops, cgroup, &memswusage_str);
-                       if (ret >= 0 && safe_uint64(memswusage_str, &memswusage, 10) == 0) {
-                               if (memlimit > memswlimit)
-                                       swtotal = 0;
-                               else
-                                       swtotal = (memswlimit - memlimit) / 1024;
-                               if (memusage > memswusage || swtotal == 0)
-                                       swusage = 0;
-                               else
-                                       swusage = (memswusage - memusage) / 1024;
-                       }
-
-                       ret = cgroup_ops->get_memory_swappiness(cgroup_ops, cgroup, &memswpriority_str);
-                       if (ret >= 0)
-                               safe_uint64(memswpriority_str, &memswpriority, 10);
-               }
-       }
+       if (wants_swap)
+               get_swap_info(cgroup, memlimit, memusage, &swtotal, &swusage, &memswpriority);
 
        total_len = snprintf(d->buf, d->size, "Filename\t\t\t\tType\t\tSize\tUsed\tPriority\n");
 
@@ -1145,7 +1164,7 @@ static int proc_meminfo_read(char *buf, size_t size, off_t offset,
        struct fuse_context *fc = fuse_get_context();
        bool wants_swap = lxcfs_has_opt(fuse_get_context()->private_data, LXCFS_SWAP_ON);
        struct file_info *d = INTTYPE_TO_PTR(fi->fh);
-       uint64_t memlimit = 0, memusage = 0, memswlimit = 0, memswusage = 0,
+       uint64_t memlimit = 0, memusage = 0,
                 hosttotal = 0, swfree = 0, swusage = 0, swtotal = 0,
                 memswpriority = 1;
        struct memory_stat mstat = {};
@@ -1197,26 +1216,8 @@ static int proc_meminfo_read(char *buf, size_t size, off_t offset,
         * Following values are allowed to fail, because swapaccount might be
         * turned off for current kernel.
         */
-       if (wants_swap) {
-               memswlimit = get_min_memlimit(cgroup, true);
-               if (memswlimit > 0) {
-                       ret = cgroup_ops->get_memory_swap_current(cgroup_ops, cgroup, &memswusage_str);
-                       if (ret >= 0 && safe_uint64(memswusage_str, &memswusage, 10) == 0) {
-                               if (memlimit > memswlimit)
-                                       swtotal = 0;
-                               else
-                                       swtotal = (memswlimit - memlimit) / 1024;
-                               if (memusage > memswusage || swtotal == 0)
-                                       swusage = 0;
-                               else
-                                       swusage = (memswusage - memusage) / 1024;
-                       }
-               }
-
-               ret = cgroup_ops->get_memory_swappiness(cgroup_ops, cgroup, &memswpriority_str);
-               if (ret >= 0)
-                       safe_uint64(memswpriority_str, &memswpriority, 10);
-       }
+       if (wants_swap)
+               get_swap_info(cgroup, memlimit, memusage, &swtotal, &swusage, &memswpriority);
 
        f = fopen_cached("/proc/meminfo", "re", &fopen_cache);
        if (!f)
@@ -1255,7 +1256,9 @@ static int proc_meminfo_read(char *buf, size_t size, off_t offset,
                                   This is because the kernel can swap as much as it
                                   wants and not only up to swtotal. */
 
-                               swtotal = memlimit + swtotal;
+                               if (!liblxcfs_memory_is_cgroupv2())
+                                       swtotal += memlimit;
+
                                if (hostswtotal < swtotal) {
                                        swtotal = hostswtotal;
                                }