diff options
Diffstat (limited to 'src/libbasic/src/util.c')
-rw-r--r-- | src/libbasic/src/util.c | 176 |
1 files changed, 122 insertions, 54 deletions
diff --git a/src/libbasic/src/util.c b/src/libbasic/src/util.c index d0db8a28fb..a7831e118a 100644 --- a/src/libbasic/src/util.c +++ b/src/libbasic/src/util.c @@ -36,6 +36,7 @@ #include "basic/alloc-util.h" #include "basic/build.h" +#include "basic/cgroup-util.h" #include "basic/def.h" #include "basic/dirent-util.h" #include "basic/fd-util.h" @@ -64,6 +65,7 @@ assert_cc(EAGAIN == EWOULDBLOCK); int saved_argc = 0; char **saved_argv = NULL; +static int saved_in_initrd = -1; size_t page_size(void) { static thread_local size_t pgsz = 0; @@ -454,11 +456,10 @@ int fork_agent(pid_t *pid, const int except[], unsigned n_except, const char *pa } bool in_initrd(void) { - static int saved = -1; struct statfs s; - if (saved >= 0) - return saved; + if (saved_in_initrd >= 0) + return saved_in_initrd; /* We make two checks here: * @@ -470,11 +471,15 @@ bool in_initrd(void) { * emptying when transititioning to the main systemd. */ - saved = access("/etc/initrd-release", F_OK) >= 0 && - statfs("/", &s) >= 0 && - is_temporary_fs(&s); + saved_in_initrd = access("/etc/initrd-release", F_OK) >= 0 && + statfs("/", &s) >= 0 && + is_temporary_fs(&s); - return saved; + return saved_in_initrd; +} + +void in_initrd_force(bool value) { + saved_in_initrd = value; } /* hey glibc, APIs with callbacks without a user pointer are so useless */ @@ -576,47 +581,6 @@ int on_ac_power(void) { return found_online || !found_offline; } -bool id128_is_valid(const char *s) { - size_t i, l; - - l = strlen(s); - if (l == 32) { - - /* Simple formatted 128bit hex string */ - - for (i = 0; i < l; i++) { - char c = s[i]; - - if (!(c >= '0' && c <= '9') && - !(c >= 'a' && c <= 'z') && - !(c >= 'A' && c <= 'Z')) - return false; - } - - } else if (l == 36) { - - /* Formatted UUID */ - - for (i = 0; i < l; i++) { - char c = s[i]; - - if ((i == 8 || i == 13 || i == 18 || i == 23)) { - if (c != '-') - return false; - } else { - if (!(c >= '0' && c <= '9') && - !(c >= 'a' && c <= 'z') && - !(c >= 'A' && c <= 'Z')) - return false; - } - } - - } else - return false; - - return true; -} - int container_get_leader(const char *machine, pid_t *pid) { _cleanup_free_ char *s = NULL, *class = NULL; const char *p; @@ -767,15 +731,119 @@ int namespace_enter(int pidns_fd, int mntns_fd, int netns_fd, int userns_fd, int } uint64_t physical_memory(void) { - long mem; + _cleanup_free_ char *root = NULL, *value = NULL; + uint64_t mem, lim; + size_t ps; + long sc; + + /* We return this as uint64_t in case we are running as 32bit process on a 64bit kernel with huge amounts of + * memory. + * + * In order to support containers nicely that have a configured memory limit we'll take the minimum of the + * physically reported amount of memory and the limit configured for the root cgroup, if there is any. */ + + sc = sysconf(_SC_PHYS_PAGES); + assert(sc > 0); + + ps = page_size(); + mem = (uint64_t) sc * (uint64_t) ps; + + if (cg_get_root_path(&root) < 0) + return mem; + + if (cg_get_attribute("memory", root, "memory.limit_in_bytes", &value)) + return mem; + + if (safe_atou64(value, &lim) < 0) + return mem; + + /* Make sure the limit is a multiple of our own page size */ + lim /= ps; + lim *= ps; + + return MIN(mem, lim); +} + +uint64_t physical_memory_scale(uint64_t v, uint64_t max) { + uint64_t p, m, ps, r; + + assert(max > 0); + + /* Returns the physical memory size, multiplied by v divided by max. Returns UINT64_MAX on overflow. On success + * the result is a multiple of the page size (rounds down). */ + + ps = page_size(); + assert(ps > 0); + + p = physical_memory() / ps; + assert(p > 0); + + m = p * v; + if (m / p != v) + return UINT64_MAX; + + m /= max; + + r = m * ps; + if (r / ps != m) + return UINT64_MAX; + + return r; +} + +uint64_t system_tasks_max(void) { + +#if SIZEOF_PID_T == 4 +#define TASKS_MAX ((uint64_t) (INT32_MAX-1)) +#elif SIZEOF_PID_T == 2 +#define TASKS_MAX ((uint64_t) (INT16_MAX-1)) +#else +#error "Unknown pid_t size" +#endif + + _cleanup_free_ char *value = NULL, *root = NULL; + uint64_t a = TASKS_MAX, b = TASKS_MAX; + + /* Determine the maximum number of tasks that may run on this system. We check three sources to determine this + * limit: + * + * a) the maximum value for the pid_t type + * b) the cgroups pids_max attribute for the system + * c) the kernel's configure maximum PID value + * + * And then pick the smallest of the three */ + + if (read_one_line_file("/proc/sys/kernel/pid_max", &value) >= 0) + (void) safe_atou64(value, &a); + + if (cg_get_root_path(&root) >= 0) { + value = mfree(value); + + if (cg_get_attribute("pids", root, "pids.max", &value) >= 0) + (void) safe_atou64(value, &b); + } + + return MIN3(TASKS_MAX, + a <= 0 ? TASKS_MAX : a, + b <= 0 ? TASKS_MAX : b); +} + +uint64_t system_tasks_max_scale(uint64_t v, uint64_t max) { + uint64_t t, m; + + assert(max > 0); + + /* Multiply the system's task value by the fraction v/max. Hence, if max==100 this calculates percentages + * relative to the system's maximum number of tasks. Returns UINT64_MAX on overflow. */ - /* We return this as uint64_t in case we are running as 32bit - * process on a 64bit kernel with huge amounts of memory */ + t = system_tasks_max(); + assert(t > 0); - mem = sysconf(_SC_PHYS_PAGES); - assert(mem > 0); + m = t * v; + if (m / t != v) /* overflow? */ + return UINT64_MAX; - return (uint64_t) mem * (uint64_t) page_size(); + return m / max; } int update_reboot_parameter_and_warn(const char *param) { |