eal: add lcore iterators
authorDavid Marchand <david.marchand@redhat.com>
Mon, 6 Jul 2020 20:52:32 +0000 (22:52 +0200)
committerDavid Marchand <david.marchand@redhat.com>
Wed, 8 Jul 2020 12:41:06 +0000 (14:41 +0200)
Add a helper to iterate all lcores.
The iterator callback is read-only wrt the lcores list.

Implement a dump function on top of this for debugging.

Signed-off-by: David Marchand <david.marchand@redhat.com>
Reviewed-by: Olivier Matz <olivier.matz@6wind.com>
Acked-by: Konstantin Ananyev <konstantin.ananyev@intel.com>
app/test/test_lcores.c
lib/librte_eal/common/eal_common_lcore.c
lib/librte_eal/common/eal_common_thread.c
lib/librte_eal/common/eal_thread.h
lib/librte_eal/freebsd/eal.c
lib/librte_eal/freebsd/eal_thread.c
lib/librte_eal/include/rte_lcore.h
lib/librte_eal/linux/eal.c
lib/librte_eal/linux/eal_thread.c
lib/librte_eal/rte_eal_version.map

index 7df827b..19a7ab9 100644 (file)
@@ -303,6 +303,7 @@ test_non_eal_lcores_callback(unsigned int eal_threads_count)
                        l[0].uninit, l[1].uninit);
                goto cleanup_threads;
        }
+       rte_lcore_dump(stdout);
        /* Release all threads, and check their states. */
        __atomic_store_n(&registered_count, 0, __ATOMIC_RELEASE);
        ret = 0;
@@ -314,6 +315,7 @@ test_non_eal_lcores_callback(unsigned int eal_threads_count)
        }
        if (ret < 0)
                goto error;
+       rte_lcore_dump(stdout);
        if (l[0].uninit != 2 || l[1].uninit != 1) {
                printf("Error: threads reported having successfully registered and unregistered, but incorrect uninit calls, expected 2, 1, got %u, %u\n",
                        l[0].uninit, l[1].uninit);
@@ -354,6 +356,7 @@ test_lcores(void)
        }
        printf("EAL threads count: %u, RTE_MAX_LCORE=%u\n", eal_threads_count,
                RTE_MAX_LCORE);
+       rte_lcore_dump(stdout);
 
        if (test_non_eal_lcores(eal_threads_count) < 0)
                return TEST_FAILED;
index c719070..d64569b 100644 (file)
@@ -12,7 +12,7 @@
 #include <rte_errno.h>
 #include <rte_lcore.h>
 #include <rte_log.h>
-#include <rte_spinlock.h>
+#include <rte_rwlock.h>
 
 #include "eal_memcfg.h"
 #include "eal_private.h"
@@ -231,7 +231,7 @@ rte_socket_id_by_idx(unsigned int idx)
        return config->numa_nodes[idx];
 }
 
-static rte_spinlock_t lcore_lock = RTE_SPINLOCK_INITIALIZER;
+static rte_rwlock_t lcore_lock = RTE_RWLOCK_INITIALIZER;
 struct lcore_callback {
        TAILQ_ENTRY(lcore_callback) next;
        char *name;
@@ -289,7 +289,7 @@ rte_lcore_callback_register(const char *name, rte_lcore_init_cb init,
        callback->init = init;
        callback->uninit = uninit;
        callback->arg = arg;
-       rte_spinlock_lock(&lcore_lock);
+       rte_rwlock_write_lock(&lcore_lock);
        if (callback->init == NULL)
                goto no_init;
        for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
@@ -315,7 +315,7 @@ no_init:
                callback->name, callback->init == NULL ? "NO " : "",
                callback->uninit == NULL ? "NO " : "");
 out:
-       rte_spinlock_unlock(&lcore_lock);
+       rte_rwlock_write_unlock(&lcore_lock);
        return callback;
 }
 
@@ -328,7 +328,7 @@ rte_lcore_callback_unregister(void *handle)
 
        if (callback == NULL)
                return;
-       rte_spinlock_lock(&lcore_lock);
+       rte_rwlock_write_lock(&lcore_lock);
        if (callback->uninit == NULL)
                goto no_uninit;
        for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
@@ -338,7 +338,7 @@ rte_lcore_callback_unregister(void *handle)
        }
 no_uninit:
        TAILQ_REMOVE(&lcore_callbacks, callback, next);
-       rte_spinlock_unlock(&lcore_lock);
+       rte_rwlock_write_unlock(&lcore_lock);
        RTE_LOG(DEBUG, EAL, "Unregistered lcore callback %s-%p.\n",
                callback->name, callback->arg);
        free_callback(callback);
@@ -352,7 +352,7 @@ eal_lcore_non_eal_allocate(void)
        struct lcore_callback *prev;
        unsigned int lcore_id;
 
-       rte_spinlock_lock(&lcore_lock);
+       rte_rwlock_write_lock(&lcore_lock);
        for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
                if (cfg->lcore_role[lcore_id] != ROLE_OFF)
                        continue;
@@ -383,7 +383,7 @@ eal_lcore_non_eal_allocate(void)
                goto out;
        }
 out:
-       rte_spinlock_unlock(&lcore_lock);
+       rte_rwlock_write_unlock(&lcore_lock);
        return lcore_id;
 }
 
@@ -393,7 +393,7 @@ eal_lcore_non_eal_release(unsigned int lcore_id)
        struct rte_config *cfg = rte_eal_get_configuration();
        struct lcore_callback *callback;
 
-       rte_spinlock_lock(&lcore_lock);
+       rte_rwlock_write_lock(&lcore_lock);
        if (cfg->lcore_role[lcore_id] != ROLE_NON_EAL)
                goto out;
        TAILQ_FOREACH(callback, &lcore_callbacks, next)
@@ -401,5 +401,62 @@ eal_lcore_non_eal_release(unsigned int lcore_id)
        cfg->lcore_role[lcore_id] = ROLE_OFF;
        cfg->lcore_count--;
 out:
-       rte_spinlock_unlock(&lcore_lock);
+       rte_rwlock_write_unlock(&lcore_lock);
+}
+
+int
+rte_lcore_iterate(rte_lcore_iterate_cb cb, void *arg)
+{
+       struct rte_config *cfg = rte_eal_get_configuration();
+       unsigned int lcore_id;
+       int ret = 0;
+
+       rte_rwlock_read_lock(&lcore_lock);
+       for (lcore_id = 0; lcore_id < RTE_MAX_LCORE; lcore_id++) {
+               if (cfg->lcore_role[lcore_id] == ROLE_OFF)
+                       continue;
+               ret = cb(lcore_id, arg);
+               if (ret != 0)
+                       break;
+       }
+       rte_rwlock_read_unlock(&lcore_lock);
+       return ret;
+}
+
+static int
+lcore_dump_cb(unsigned int lcore_id, void *arg)
+{
+       struct rte_config *cfg = rte_eal_get_configuration();
+       char cpuset[RTE_CPU_AFFINITY_STR_LEN];
+       const char *role;
+       FILE *f = arg;
+       int ret;
+
+       switch (cfg->lcore_role[lcore_id]) {
+       case ROLE_RTE:
+               role = "RTE";
+               break;
+       case ROLE_SERVICE:
+               role = "SERVICE";
+               break;
+       case ROLE_NON_EAL:
+               role = "NON_EAL";
+               break;
+       default:
+               role = "UNKNOWN";
+               break;
+       }
+
+       ret = eal_thread_dump_affinity(&lcore_config[lcore_id].cpuset, cpuset,
+               sizeof(cpuset));
+       fprintf(f, "lcore %u, socket %u, role %s, cpuset %s%s\n", lcore_id,
+               rte_lcore_to_socket_id(lcore_id), role, cpuset,
+               ret == 0 ? "" : "...");
+       return 0;
+}
+
+void
+rte_lcore_dump(FILE *f)
+{
+       rte_lcore_iterate(lcore_dump_cb, f);
 }
index 4bc5c31..04c2b37 100644 (file)
@@ -105,17 +105,14 @@ rte_thread_get_affinity(rte_cpuset_t *cpusetp)
 }
 
 int
-eal_thread_dump_affinity(char *str, unsigned size)
+eal_thread_dump_affinity(rte_cpuset_t *cpuset, char *str, unsigned int size)
 {
-       rte_cpuset_t cpuset;
        unsigned cpu;
        int ret;
        unsigned int out = 0;
 
-       rte_thread_get_affinity(&cpuset);
-
        for (cpu = 0; cpu < CPU_SETSIZE; cpu++) {
-               if (!CPU_ISSET(cpu, &cpuset))
+               if (!CPU_ISSET(cpu, cpuset))
                        continue;
 
                ret = snprintf(str + out,
@@ -138,6 +135,15 @@ exit:
        return ret;
 }
 
+int
+eal_thread_dump_current_affinity(char *str, unsigned int size)
+{
+       rte_cpuset_t cpuset;
+
+       rte_thread_get_affinity(&cpuset);
+       return eal_thread_dump_affinity(&cpuset, str, size);
+}
+
 void
 __rte_thread_init(unsigned int lcore_id, rte_cpuset_t *cpuset)
 {
index dc1fc6e..4a49117 100644 (file)
@@ -32,13 +32,15 @@ unsigned eal_cpu_socket_id(unsigned cpu_id);
 #define RTE_CPU_AFFINITY_STR_LEN            256
 
 /**
- * Dump the current pthread cpuset.
+ * Dump the cpuset as a human readable string.
  * This function is private to EAL.
  *
  * Note:
  *   If the dump size is greater than the size of given buffer,
  *   the string will be truncated and with '\0' at the end.
  *
+ * @param cpuset
+ *   The CPU affinity object to dump.
  * @param str
  *   The string buffer the cpuset will dump to.
  * @param size
@@ -47,6 +49,13 @@ unsigned eal_cpu_socket_id(unsigned cpu_id);
  *   0 for success, -1 if truncation happens.
  */
 int
-eal_thread_dump_affinity(char *str, unsigned size);
+eal_thread_dump_affinity(rte_cpuset_t *cpuset, char *str, unsigned int size);
+
+/**
+ * Dump the current thread cpuset.
+ * This is a wrapper on eal_thread_dump_affinity().
+ */
+int
+eal_thread_dump_current_affinity(char *str, unsigned int size);
 
 #endif /* EAL_THREAD_H */
index 1891284..798add0 100644 (file)
@@ -858,7 +858,7 @@ rte_eal_init(int argc, char **argv)
        __rte_thread_init(config->master_lcore,
                &lcore_config[config->master_lcore].cpuset);
 
-       ret = eal_thread_dump_affinity(cpuset, sizeof(cpuset));
+       ret = eal_thread_dump_current_affinity(cpuset, sizeof(cpuset));
 
        RTE_LOG(DEBUG, EAL, "Master lcore %u is ready (tid=%p;cpuset=[%s%s])\n",
                config->master_lcore, thread_id, cpuset,
index 0788a54..99b5fef 100644 (file)
@@ -92,7 +92,7 @@ eal_thread_loop(__rte_unused void *arg)
 
        __rte_thread_init(lcore_id, &lcore_config[lcore_id].cpuset);
 
-       ret = eal_thread_dump_affinity(cpuset, sizeof(cpuset));
+       ret = eal_thread_dump_current_affinity(cpuset, sizeof(cpuset));
        RTE_LOG(DEBUG, EAL, "lcore %u is ready (tid=%p;cpuset=[%s%s])\n",
                lcore_id, thread_id, cpuset, ret == 0 ? "" : "...");
 
index 6e7206c..b8b64a6 100644 (file)
@@ -261,8 +261,8 @@ typedef void (*rte_lcore_uninit_cb)(unsigned int lcore_id, void *arg);
  * If this step succeeds, the callbacks are put in the lcore callbacks list
  * that will get called for each lcore allocation/release.
  *
- * Note: callbacks execution is serialised under a lock protecting the lcores
- * and callbacks list.
+ * Note: callbacks execution is serialised under a write lock protecting the
+ * lcores and callbacks list.
  *
  * @param name
  *   A name serving as a small description for this callback.
@@ -299,6 +299,49 @@ __rte_experimental
 void
 rte_lcore_callback_unregister(void *handle);
 
+/**
+ * Callback prototype for iterating over lcores.
+ *
+ * @param lcore_id
+ *   The lcore to consider.
+ * @param arg
+ *   An opaque pointer coming from the caller.
+ * @return
+ *   - 0 lets the iteration continue.
+ *   - !0 makes the iteration stop.
+ */
+typedef int (*rte_lcore_iterate_cb)(unsigned int lcore_id, void *arg);
+
+/**
+ * Iterate on all active lcores (ROLE_RTE, ROLE_SERVICE and ROLE_NON_EAL).
+ * No modification on the lcore states is allowed in the callback.
+ *
+ * Note: as opposed to init/uninit callbacks, iteration callbacks can be
+ * invoked in parallel as they are run under a read lock protecting the lcores
+ * and callbacks list.
+ *
+ * @param cb
+ *   The callback that gets passed each lcore.
+ * @param arg
+ *   An opaque pointer passed to cb.
+ * @return
+ *   Same return code as the callback last invocation (see rte_lcore_iterate_cb
+ *   description).
+ */
+__rte_experimental
+int
+rte_lcore_iterate(rte_lcore_iterate_cb cb, void *arg);
+
+/**
+ * List all lcores.
+ *
+ * @param f
+ *   The output stream where the dump should be sent.
+ */
+__rte_experimental
+void
+rte_lcore_dump(FILE *f);
+
 /**
  * Set core affinity of the current thread.
  * Support both EAL and non-EAL thread and update TLS.
index 0cf899c..0960f01 100644 (file)
@@ -1222,7 +1222,7 @@ rte_eal_init(int argc, char **argv)
        __rte_thread_init(config->master_lcore,
                &lcore_config[config->master_lcore].cpuset);
 
-       ret = eal_thread_dump_affinity(cpuset, sizeof(cpuset));
+       ret = eal_thread_dump_current_affinity(cpuset, sizeof(cpuset));
        RTE_LOG(DEBUG, EAL, "Master lcore %u is ready (tid=%zx;cpuset=[%s%s])\n",
                config->master_lcore, (uintptr_t)thread_id, cpuset,
                ret == 0 ? "" : "...");
index e0440c0..48a2c11 100644 (file)
@@ -92,7 +92,7 @@ eal_thread_loop(__rte_unused void *arg)
 
        __rte_thread_init(lcore_id, &lcore_config[lcore_id].cpuset);
 
-       ret = eal_thread_dump_affinity(cpuset, sizeof(cpuset));
+       ret = eal_thread_dump_current_affinity(cpuset, sizeof(cpuset));
        RTE_LOG(DEBUG, EAL, "lcore %u is ready (tid=%zx;cpuset=[%s%s])\n",
                lcore_id, (uintptr_t)thread_id, cpuset, ret == 0 ? "" : "...");
 
index 41f3950..bdbe26c 100644 (file)
@@ -398,6 +398,8 @@ EXPERIMENTAL {
        rte_eal_vfio_get_vf_token;
        rte_lcore_callback_register;
        rte_lcore_callback_unregister;
+       rte_lcore_dump;
+       rte_lcore_iterate;
        rte_thread_register;
        rte_thread_unregister;
 };