--- /dev/null
+#include <malloc.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/mman.h>
+
+#include "l2tpns.h"
+#include "tbf.h"
+
+// Need a time interval.
+
+#define TBF_MAX_QUEUE 2 // Maximum of 2 queued packet per
+#define TBF_MAX_SIZE 3000 // Maxiumum queued packet size is 2048.
+
+#define TBF_MAX_CREDIT 6000 // Maximum 6000 bytes of credit.
+#define TBF_RATE 360 // 360 bytes per 1/10th of a second.
+
+typedef struct {
+ int credit;
+ int lasttime;
+ int queued;
+ int oldest; // Position of packet in the ring buffer.
+ sessionidt sid; // associated session ID.
+ int max_credit; // Maximum amount of credit available (burst size).
+ int rate; // How many bytes of credit per second we get? (sustained rate)
+ void (*send)(sessionidt s, u8 *, int); // Routine to actually send out the data.
+ int prev; // Timer chain position.
+ int next; // Timer chain position.
+
+ u32 b_queued; // Total bytes sent through this TBF
+ u32 b_sent; // Total bytes sucessfully made it to the network.
+ u32 p_queued; // ditto packets.
+ u32 p_sent; // ditto packets.
+ u32 b_dropped; // Total bytes dropped.
+ u32 p_dropped; // Total packets dropped.
+ u32 p_delayed; // Total packets not sent immediately.
+
+ int sizes[TBF_MAX_QUEUE];
+ char packets[TBF_MAX_QUEUE][TBF_MAX_SIZE];
+} tbft;
+
+
+tbft * filter_list = NULL;
+int filter_list_size = 0;
+
+static int timer_chain = -1; // Head of timer chain.
+
+static void tbf_run_queue(int tbf_id);
+
+void init_tbf(void)
+{
+ filter_list = mmap(NULL, sizeof(*filter_list) * MAXTBFS, PROT_READ | PROT_WRITE, MAP_SHARED | MAP_ANONYMOUS, 0, 0);
+ if (!filter_list)
+ return;
+
+ filter_list_size = MAXTBFS;
+ filter_list[0].sid = -1; // Reserved.
+}
+//
+// Put a TBF on the timer list.
+// This is a doubly linked list..
+// We put ourselves on the tail of the list.
+//
+static void add_to_timer(int id)
+{
+ if (!filter_list)
+ return;
+
+ if (timer_chain == -1) {
+ filter_list[id].next = filter_list[id].prev = id;
+ timer_chain = id;
+ return;
+ }
+
+ filter_list[id].next = timer_chain;
+ filter_list[id].prev = filter_list[timer_chain].prev;
+ filter_list[filter_list[timer_chain].prev].next = id;
+ filter_list[timer_chain].prev = id;
+}
+
+//
+// Remove a TBF from the timer list.
+// This is a doubly linked list.
+static void del_from_timer(int id)
+{
+ if (!filter_list)
+ return;
+
+ if (filter_list[id].next == id) { // Last element in chain?
+ if (timer_chain != id) { // WTF?
+ log(0,0,0,0, "Removed a singleton element from TBF, but tc didn't point to it!\n");
+ } else
+ timer_chain = -1;
+ filter_list[id].next = filter_list[id].prev = 0;
+ return;
+ }
+
+ filter_list[filter_list[id].next].prev = filter_list[id].prev;
+ filter_list[filter_list[id].prev].next = filter_list[id].next;
+ if (timer_chain == id)
+ timer_chain = filter_list[id].next;
+
+ filter_list[id].next = filter_list[id].prev = 0; // Mark as off the timer chain.
+}
+
+//
+// Free a token bucket filter structure for re-use.
+//
+
+int free_tbf(int tid)
+{
+ if (tid < 1) // Make sure we don't free id # 0
+ return -1;
+
+ if (!filter_list) // WTF?
+ return -1;
+
+ if (filter_list[tid].next)
+ del_from_timer(tid);
+ filter_list[tid].sid = 0;
+
+ return 0; // Done!
+}
+
+//
+// Allocate a new token bucket filter.
+//
+int new_tbf(int sid, int max_credit, int rate, void (*f)(sessionidt, u8 *, int))
+{
+ int i;
+ static int p = 0;
+
+ log(3,0,0,0, "Allocating new TBF (sess %d, rate %d, helper %p)\n", sid, rate, f);
+
+ if (!filter_list)
+ return 0; // Couldn't alloc memory!
+
+// again:
+
+ for (i = 0 ; i < filter_list_size ; ++i, p = (p+1)%filter_list_size ) {
+ if (filter_list[p].sid)
+ continue;
+
+ memset((void*) &filter_list[p], 0, sizeof(filter_list[p]) ); // Clear counters and data.
+ filter_list[p].sid = sid;
+ filter_list[p].credit = max_credit;
+ filter_list[p].queued = 0;
+ filter_list[p].max_credit = max_credit;
+ filter_list[p].rate = rate;
+ filter_list[p].oldest = 0;
+ filter_list[p].send = f;
+ return p;
+ }
+
+ log(0,0,0,0, "Ran out of token bucket filters! Sess %d will be un-throttled\n", sid);
+ return 0;
+
+#if 0
+ // Not using. Disasterous if called via the CLI! :)
+ // All allocated filters are used! Increase the size of the allocated
+ // filters.
+
+ i = filter_list_size;
+ filter_list_size = filter_list_size * 2 + 1;
+
+ filter_list = realloc(filter_list, filter_list_size * sizeof(*filter_list) );
+
+ for (; i < filter_list_size; ++i)
+ filter_list[i].sid = 0;
+
+ goto again;
+#endif
+}
+
+//
+// Sanity check all the TBF records. This is
+// typically done when we become a master..
+//
+void fsck_tbfs(void)
+{
+ int i , sid;
+
+ if (!filter_list)
+ return;
+
+ for (i = 1; i < filter_list_size; ++i) {
+ if (!filter_list[i].sid) // Is it used??
+ continue;
+
+ sid = filter_list[i].sid;
+ if (i != session[sid].tbf_in &&
+ i != session[sid].tbf_out) { // Ooops.
+
+ free_tbf(i); // Mark it as free...
+ }
+ }
+
+ for (i = 0; i < config->cluster_highest_sessionid ; ++i) {
+ if (session[i].tbf_in && filter_list[session[i].tbf_in].sid != i) {
+ filter_list[session[i].tbf_in].sid = i; // Ouch!? FIXME. What to do here?
+ }
+ if (session[i].tbf_out && filter_list[session[i].tbf_out].sid != i) {
+ filter_list[session[i].tbf_out].sid = i; // Ouch!? FIXME. What to do here?
+ }
+ }
+}
+
+
+//
+// Run a packet through a token bucket filter.
+// If we can send it right away, we do. Else we
+// try and queue it to send later. Else we drop it.
+//
+int tbf_queue_packet(int tbf_id, char * data, int size)
+{
+ int i;
+ tbft * f;
+
+ if (!filter_list)
+ return -1;
+
+ if (tbf_id > filter_list_size || tbf_id < 1) { // Out of range ID??
+ // Very bad. Just drop it.
+ return -1;
+ }
+
+ f = &filter_list[tbf_id];
+
+ if (!f->sid) // Is this a real structure??
+ return -1;
+
+ tbf_run_queue(tbf_id); // Caculate credit and send any queued packets if possible..
+
+ f->b_queued += size;
+ f->p_queued ++;
+
+ if (!f->queued && f->credit > size) { // If the queue is empty, and we have
+ // enough credit, just send it now.
+ f->credit -= size;
+ if (f->send) {
+ f->send(f->sid, data, size);
+ f->b_sent += size;
+ f->p_sent ++;
+ } else {
+ f->b_dropped += size;
+ f->p_dropped ++;
+ }
+ return size;
+ }
+
+ // Not enough credit. Can we have room in the queue?
+ if (f->queued >= TBF_MAX_QUEUE) {
+ f->p_dropped ++;
+ f->b_dropped += size;
+ return -1; // No, just drop it.
+ }
+
+ // Is it too big to fit into a queue slot?
+ if (size >= TBF_MAX_SIZE) {
+ f->p_dropped ++;
+ f->b_dropped += size;
+ return -1; // Yes, just drop it.
+ }
+
+ // Ok. We have a slot, and it's big enough to
+ // contain the packet, so queue the packet!
+ i = ( f->oldest + f->queued ) % TBF_MAX_QUEUE;
+ memcpy(f->packets[i], data, size);
+
+ f->sizes[i] = size;
+ f->queued ++;
+ f->p_delayed ++;
+
+ if (!f->next) // Are we off the timer chain?
+ add_to_timer(tbf_id); // Put ourselves on the timer chain.
+
+ return 0; // All done.
+}
+
+//
+// Send queued packets from the filter if possible.
+// (We're normally only called if this is possible.. )
+static void tbf_run_queue(int tbf_id)
+{
+ tbft * f;
+
+ if (!filter_list)
+ return;
+
+ f = &filter_list[tbf_id];
+
+ // Calculate available credit...
+ f->credit += (config->current_time - f->lasttime) * f->rate / 10; // current time is 1/10th of a second.
+ if (f->credit > f->max_credit)
+ f->credit = f->max_credit;
+ f->lasttime = config->current_time;
+
+ while (f->queued > 0 && f->credit >= f->sizes[f->oldest]) { // While we have enough credit..
+
+ if (f->send) {
+ f->send(f->sid, f->packets[f->oldest], f->sizes[f->oldest]);
+ f->b_sent += f->sizes[f->oldest];
+ f->p_sent ++;
+ } else {
+ f->b_dropped += f->sizes[f->oldest];
+ f->p_dropped ++;
+ }
+
+ f->credit -= f->sizes[f->oldest];
+
+ f->oldest = (f->oldest + 1 ) % TBF_MAX_QUEUE;
+ f->queued--; // One less queued packet..
+ }
+
+ if (f->queued) // Still more to do. Hang around on the timer list.
+ return;
+
+ if (f->next) // Are we on the timer list??
+ del_from_timer(tbf_id); // Nothing more to do. Get off the timer list.
+}
+
+//
+// Periodically walk the timer list..
+//
+int tbf_run_timer(void)
+{
+ int i = timer_chain;
+ int count = filter_list_size + 1; // Safety check.
+ int last = -1;
+ int tbf_id; // structure being processed.
+
+ if (timer_chain < 0)
+ return 0; // Nothing to do...
+
+ if (!filter_list) // No structures built yet.
+ return 0;
+
+ last = filter_list[i].prev; // last element to process.
+
+ do {
+ tbf_id = i;
+ i = filter_list[i].next; // Get the next in the queue.
+
+ tbf_run_queue(tbf_id); // Run the timer queue..
+ } while ( timer_chain > 0 && i && tbf_id != last && --count > 0);
+
+
+#if 0 // Debugging.
+ for (i = 0; i < filter_list_size; ++i) {
+ if (!filter_list[i].next)
+ continue;
+ if (filter_list[i].lasttime == config->current_time) // Did we just run it?
+ continue;
+
+ log(1,0,0,0, "Missed tbf %d! Not on the timer chain?(n %d, p %d, tc %d)\n", i,
+ filter_list[i].next, filter_list[i].prev, timer_chain);
+ tbf_run_queue(i);
+ }
+#endif
+
+ return 1;
+}
+
+int cmd_show_tbf(struct cli_def *cli, char *command, char **argv, int argc)
+{
+ int i;
+ int count = 0;
+
+ if (!config->cluster_iam_master) {
+ cli_print(cli, "Command can't be run on a slave.");
+ return CLI_OK;
+ }
+ if (!filter_list)
+ return CLI_OK;
+
+ cli_print(cli,"%6s %5s %5s %6s %6s | %7s %7s %8s %8s %8s %8s", "TBF#", "Sid", "Rate", "Credit", "Queued",
+ "ByteIn","PackIn","ByteSent","PackSent", "PackDrop", "PackDelay");
+
+ for (i = 1; i < filter_list_size; ++i) {
+ if (!filter_list[i].sid) // Is it used?
+ continue; // No.
+
+ cli_print(cli, "%5d%1s %5d %5d %6d %6d | %7d %7d %8d %8d %8d %8d",
+ i, (filter_list[i].next ? "*" : " "),
+ filter_list[i].sid,
+ filter_list[i].rate * 8,
+ filter_list[i].credit,
+ filter_list[i].queued,
+
+ filter_list[i].b_queued,
+ filter_list[i].p_queued,
+ filter_list[i].b_sent,
+ filter_list[i].p_sent,
+ filter_list[i].p_dropped,
+ filter_list[i].p_delayed);
+ ++count;
+ }
+ cli_print(cli, "%d tbf entries used, %d total", count, filter_list_size);
+ return CLI_OK;
+}
+
projects / l2tpns.git / blobdiff