diff options
| -rw-r--r-- | src/vnet/session/session.c | 1 | ||||
| -rw-r--r-- | src/vnet/session/session.h | 147 |
2 files changed, 148 insertions, 0 deletions
diff --git a/src/vnet/session/session.c b/src/vnet/session/session.c index 2a5d13d57c5..60991cdd8d0 100644 --- a/src/vnet/session/session.c +++ b/src/vnet/session/session.c @@ -1887,6 +1887,7 @@ session_manager_main_enable (vlib_main_t * vm) /* Allocate cache line aligned worker contexts */ vec_validate_aligned (smm->wrk, num_threads - 1, CLIB_CACHE_LINE_BYTES); + clib_spinlock_init (&session_main.pool_realloc_lock); for (i = 0; i < num_threads; i++) { diff --git a/src/vnet/session/session.h b/src/vnet/session/session.h index fe8a85cd5f4..0ea621aa385 100644 --- a/src/vnet/session/session.h +++ b/src/vnet/session/session.h @@ -200,6 +200,12 @@ typedef struct session_main_ transport_proto_t last_transport_proto_type; + /** Number of workers at pool realloc barrier */ + u32 pool_realloc_at_barrier; + + /** Lock to synchronize parallel forced reallocs */ + clib_spinlock_t pool_realloc_lock; + /* * Config parameters */ @@ -784,6 +790,147 @@ clib_error_t *vnet_session_enable_disable (vlib_main_t * vm, u8 is_en); session_t *session_alloc_for_connection (transport_connection_t * tc); session_t *session_alloc_for_half_open (transport_connection_t *tc); +typedef void (pool_safe_realloc_rpc_fn) (void *rpc_args); + +typedef struct +{ + u8 ph[STRUCT_OFFSET_OF (pool_header_t, max_elts) + 4]; + u32 flag; +} pool_safe_realloc_header_t; + +STATIC_ASSERT_SIZEOF (pool_safe_realloc_header_t, sizeof (pool_header_t)); + +#define POOL_REALLOC_SAFE_ELT_THRESH 32 + +#define pool_realloc_flag(PH) \ + ((pool_safe_realloc_header_t *) pool_header (PH))->flag + +#define pool_realloc_safe_aligned(P, align) \ + do \ + { \ + vlib_main_t *vm = vlib_get_main (); \ + u32 free_elts, max_elts, n_alloc; \ + ASSERT (vlib_get_thread_index () == 0); \ + vlib_worker_thread_barrier_sync (vm); \ + free_elts = pool_free_elts (P); \ + max_elts = pool_max_len (P); \ + n_alloc = clib_max (2 * max_elts, POOL_REALLOC_SAFE_ELT_THRESH); \ + pool_alloc_aligned (P, free_elts + n_alloc, align); \ + clib_bitmap_validate (pool_header (P)->free_bitmap, \ + max_elts + n_alloc); \ + pool_realloc_flag (P) = 0; \ + vlib_worker_thread_barrier_release (vm); \ + } \ + while (0) + +always_inline void +pool_program_safe_realloc (void *p, u32 thread_index, + pool_safe_realloc_rpc_fn *rpc_fn) +{ + /* Reuse pad as a realloc flag */ + if (pool_realloc_flag (p)) + return; + + pool_realloc_flag (p) = 1; + session_send_rpc_evt_to_thread (0 /* thread index */, rpc_fn, + uword_to_pointer (thread_index, void *)); +} + +always_inline void +pool_realloc_maybe_wait_at_barrier (void) +{ + if (!(*vlib_worker_threads->wait_at_barrier)) + return; + + /* Node refork required. Don't stop at the barrier from within a node */ + if (*vlib_worker_threads->node_reforks_required) + return; + + clib_atomic_fetch_add (vlib_worker_threads->workers_at_barrier, 1); + + while (*vlib_worker_threads->wait_at_barrier) + ; + + clib_atomic_fetch_add (vlib_worker_threads->workers_at_barrier, -1); +} + +#define pool_realloc_all_at_barrier(_not) \ + (*vlib_worker_threads->workers_at_barrier >= (vlib_num_workers () - _not)) + +#define pool_realloc_safe_force(P) \ + do \ + { \ + ALWAYS_ASSERT (*vlib_worker_threads->node_reforks_required); \ + if (pool_realloc_all_at_barrier (1)) \ + { \ + pool_alloc (P, pool_max_len (P)); \ + } \ + else \ + { \ + session_main_t *sm = &session_main; \ + clib_warning ("forced pool realloc"); \ + clib_atomic_fetch_add (&sm->pool_realloc_at_barrier, 1); \ + while (!pool_realloc_all_at_barrier (sm->pool_realloc_at_barrier)) \ + ; \ + clib_spinlock_lock (&sm->pool_realloc_lock); \ + pool_alloc (P, pool_max_len (P)); \ + clib_spinlock_unlock (&sm->pool_realloc_lock); \ + clib_atomic_fetch_add (&sm->pool_realloc_at_barrier, -1); \ + } \ + } \ + while (0) + +#define pool_needs_realloc(P) \ + ((!P) || \ + (vec_len (pool_header (P)->free_indices) < POOL_REALLOC_SAFE_ELT_THRESH && \ + pool_free_elts (P) < POOL_REALLOC_SAFE_ELT_THRESH)) + +#define pool_get_aligned_safe(P, E, thread_index, rpc_fn, align) \ + do \ + { \ + ASSERT (vlib_get_thread_index () == thread_index || \ + vlib_thread_is_main_w_barrier ()); \ + if (PREDICT_FALSE (pool_needs_realloc (P))) \ + { \ + if (PREDICT_FALSE (!(P))) \ + { \ + pool_alloc_aligned (P, 2 * POOL_REALLOC_SAFE_ELT_THRESH, \ + align); \ + } \ + else if (PREDICT_FALSE (pool_free_elts (P) < \ + POOL_REALLOC_SAFE_ELT_THRESH / 2)) \ + { \ + volatile typeof (P) *PP = &(P); \ + pool_program_safe_realloc (P, thread_index, rpc_fn); \ + if (thread_index) \ + { \ + while (pool_realloc_flag (P)) \ + { \ + /* If refork required abort and consume existing elt */ \ + if (*vlib_worker_threads->node_reforks_required) \ + { \ + /* All workers at barrier realloc now */ \ + if (pool_realloc_all_at_barrier (1)) \ + pool_alloc_aligned (P, pool_max_len (P), align); \ + break; \ + } \ + pool_realloc_maybe_wait_at_barrier (); \ + } \ + if (pool_free_elts (P) == 0) \ + pool_realloc_safe_force (P); \ + ALWAYS_ASSERT (pool_free_elts (P) > 0); \ + } \ + (P) = *PP; \ + } \ + else \ + { \ + pool_program_safe_realloc (P, thread_index, rpc_fn); \ + } \ + } \ + pool_get_aligned (P, E, align); \ + } \ + while (0) + #endif /* __included_session_h__ */ /* |