core: introduce MemorySwapMax=

Similar to MemoryMax=, MemorySwapMax= limits swap usage. This controls
controls "memory.swap.max" attribute in unified cgroup.

diff --git a/src/core/cgroup.c b/src/core/cgroup.c
index 4702c54a930c948dabaf640861b821f5c623e261..bc454551b7eaad32331edd478e0bd33631191a7f 100644 (file)
--- a/src/core/cgroup.c
+++ b/src/core/cgroup.c
@@ -64,6 +64,7 @@ void cgroup_context_init(CGroupContext *c) {
 
         c->memory_high = CGROUP_LIMIT_MAX;
         c->memory_max = CGROUP_LIMIT_MAX;
+       c->memory_swap_max = CGROUP_LIMIT_MAX;
 
         c->memory_limit = CGROUP_LIMIT_MAX;
 
@@ -169,6 +170,7 @@ void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) {
                 "%sMemoryLow=%" PRIu64 "\n"
                 "%sMemoryHigh=%" PRIu64 "\n"
                 "%sMemoryMax=%" PRIu64 "\n"
+                "%sMemorySwapMax=%" PRIu64 "\n"
                 "%sMemoryLimit=%" PRIu64 "\n"
                 "%sTasksMax=%" PRIu64 "\n"
                 "%sDevicePolicy=%s\n"
@@ -188,6 +190,7 @@ void cgroup_context_dump(CGroupContext *c, FILE* f, const char *prefix) {
                 prefix, c->memory_low,
                 prefix, c->memory_high,
                 prefix, c->memory_max,
+                prefix, c->memory_swap_max,
                 prefix, c->memory_limit,
                 prefix, c->tasks_max,
                 prefix, cgroup_device_policy_to_string(c->device_policy),
@@ -522,7 +525,7 @@ static unsigned cgroup_apply_blkio_device_limit(Unit *u, const char *dev_path, u
 }
 
 static bool cgroup_context_has_unified_memory_config(CGroupContext *c) {
-        return c->memory_low > 0 || c->memory_high != CGROUP_LIMIT_MAX || c->memory_max != CGROUP_LIMIT_MAX;
+        return c->memory_low > 0 || c->memory_high != CGROUP_LIMIT_MAX || c->memory_max != CGROUP_LIMIT_MAX || c->memory_swap_max != CGROUP_LIMIT_MAX;
 }
 
 static void cgroup_apply_unified_memory_limit(Unit *u, const char *file, uint64_t v) {
@@ -741,10 +744,12 @@ static void cgroup_context_apply(Unit *u, CGroupMask mask, ManagerState state) {
         if ((mask & CGROUP_MASK_MEMORY) && !is_root) {
                 if (cg_unified() > 0) {
                         uint64_t max = c->memory_max;
-
-                        if (cgroup_context_has_unified_memory_config(c))
-                                max = c->memory_max;
-                        else {
+                        uint64_t swap_max = c->memory_swap_max;
+ 
+                        if (cgroup_context_has_unified_memory_config(c)) {
+                                 max = c->memory_max;
+                                swap_max = c->memory_swap_max;
+                        } else {
                                 max = c->memory_limit;
 
                                 if (max != CGROUP_LIMIT_MAX)
@@ -754,6 +759,7 @@ static void cgroup_context_apply(Unit *u, CGroupMask mask, ManagerState state) {
                         cgroup_apply_unified_memory_limit(u, "memory.low", c->memory_low);
                         cgroup_apply_unified_memory_limit(u, "memory.high", c->memory_high);
                         cgroup_apply_unified_memory_limit(u, "memory.max", max);
+                        cgroup_apply_unified_memory_limit(u, "memory.swap.max", swap_max);
                 } else {
                         char buf[DECIMAL_STR_MAX(uint64_t) + 1];
                         uint64_t val = c->memory_limit;

diff --git a/src/core/cgroup.h b/src/core/cgroup.h
index c3b87bfc5ce5249b6c49013caf1ebd8fb501fa0f..f70a6a996ffafd1751126606353d2d521bc965af 100644 (file)
--- a/src/core/cgroup.h
+++ b/src/core/cgroup.h
@@ -98,6 +98,7 @@ struct CGroupContext {
         uint64_t memory_low;
         uint64_t memory_high;
         uint64_t memory_max;
+        uint64_t memory_swap_max;
 
         /* For legacy hierarchies */
         uint64_t cpu_shares;