trafgen: inherit netsniff-ng's -H -Q options

Also make these options available to trafgen.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>

3 files changed, 32 insertions, 3 deletions

diff --git a/trafgen.8 b/trafgen.8
index d311084..6a49fd0 100644
--- a/trafgen.8
+++ b/trafgen.8
@@ -152,6 +152,15 @@ testing.
 .SS -u <uid>, --user <uid> resp. -g <gid>, --group <gid>
 After ring setup, drop privileges to a non-root user/group combination.
 .PP
+.SS -H, --prio-high
+Set this process as a high priority process in order to achieve a higher
+scheduling rate resp. CPU time. This is however not the default setting, since
+it could lead to starvation of other processes, for example low priority kernel
+threads.
+.PP
+.SS -Q, --notouch-irq
+Do not reassign the NIC's IRQ CPU affinity settings.
+.PP
 .SS -V, --verbose
 Let trafgen be more talkative and let it print the parsed configuration and
 some ring buffer statistics.
diff --git a/trafgen.c b/trafgen.c
index e502fff..b27cb70 100644
--- a/trafgen.c
+++ b/trafgen.c
@@ -80,7 +80,7 @@ size_t plen = 0;
 struct packet_dyn *packet_dyn = NULL;
 size_t dlen = 0;
 
-static const char *short_options = "d:c:n:t:vJhS:rk:i:o:VRs:P:eE:pu:g:C";
+static const char *short_options = "d:c:n:t:vJhS:rk:i:o:VRs:P:eE:pu:g:CHQ";
 static const struct option long_options[] = {
 	{"dev",			required_argument,	NULL, 'd'},
 	{"out",			required_argument,	NULL, 'o'},
@@ -95,6 +95,8 @@ static const struct option long_options[] = {
 	{"seed",		required_argument,	NULL, 'E'},
 	{"user",		required_argument,	NULL, 'u'},
 	{"group",		required_argument,	NULL, 'g'},
+	{"prio-high",		no_argument,		NULL, 'H'},
+	{"notouch-irq",		no_argument,		NULL, 'Q'},
 	{"jumbo-support",	no_argument,		NULL, 'J'},
 	{"no-cpu-stats",	no_argument,		NULL, 'C'},
 	{"cpp",			no_argument,		NULL, 'p'},
@@ -189,6 +191,8 @@ static void __noreturn help(void)
 	     "  -E|--seed <uint>               Manually set srand(3) seed\n"
 	     "  -u|--user <userid>             Drop privileges and change to userid\n"
 	     "  -g|--group <groupid>           Drop privileges and change to groupid\n"
+	     "  -H|--prio-high                 Make this high priority process\n"
+	     "  -Q|--notouch-irq               Do not touch IRQ CPU affinity of NIC\n"
 	     "  -V|--verbose                   Be more verbose\n"
 	     "  -C|--no-cpu-stats              Do not print CPU time statistics on exit\n"
 	     "  -v|--version                   Show version and exit\n"
@@ -880,6 +884,7 @@ static unsigned int generate_srand_seed(void)
 int main(int argc, char **argv)
 {
 	bool slow = false, invoke_cpp = false, reseed = true, cpustats = true;
+	bool prio_high = false, set_irq_aff = true;
 	int c, opt_index, vals[4] = {0}, irq;
 	uint64_t gap = 0;
 	unsigned int i, j;
@@ -923,6 +928,12 @@ int main(int argc, char **argv)
 		case 'o':
 			ctx.device = xstrndup(optarg, IFNAMSIZ);
 			break;
+		case 'H':
+			prio_high = true;
+			break;
+		case 'Q':
+			set_irq_aff = false;
+			break;
 		case 'r':
 			ctx.rand = true;
 			break;
@@ -1060,6 +1071,11 @@ int main(int argc, char **argv)
 	register_signal(SIGHUP, signal_handler);
 	register_signal_f(SIGALRM, timer_elapsed, SA_SIGINFO);
 
+	if (prio_high) {
+		set_proc_prio(-20);
+		set_sched_status(SCHED_FIFO, sched_get_priority_max(SCHED_FIFO));
+	}
+
 	set_system_socket_memory(vals, array_size(vals));
 	xlockme();
 
@@ -1072,7 +1088,8 @@ int main(int argc, char **argv)
 	}
 
 	irq = device_irq_number(ctx.device);
-	device_set_irq_affinity_list(irq, 0, ctx.cpus - 1);
+	if (set_irq_aff)
+		device_set_irq_affinity_list(irq, 0, ctx.cpus - 1);
 
 	stats = setup_shared_var(ctx.cpus);
 
@@ -1128,7 +1145,8 @@ int main(int argc, char **argv)
 thread_out:
 	xunlockme();
 	destroy_shared_var(stats, ctx.cpus);
-	device_restore_irq_affinity_list();
+	if (set_irq_aff)
+		device_restore_irq_affinity_list();
 
 	free(ctx.device);
 	free(ctx.device_trans);
diff --git a/trafgen.zsh b/trafgen.zsh
index 8a90381..adfd8ad 100644
--- a/trafgen.zsh
+++ b/trafgen.zsh
@@ -48,6 +48,8 @@ _arguments -s -S \
     "(-E --seed)"{-E,--seed}"[Manually set srand(3) seed]" \
     "(-u --user)"{-u,--user}"[Drop privileges and change to userid]:user:_user_info" \
     "(-g --group)"{-g,--group}"[Drop privileges and change to groupid]:group:_group_info" \
+    "(-H --prio-high)"{-H,--prio-high}"[Make this high priority process]" \
+    "(-Q --notouch-irq)"{-Q,--notouch-irq}"[Do not touch IRQ CPU affinity of NIC]" \
     "(-e --example)"{-e,--example}"[Show built-in packet config example]:" \
     "(-V --verbose)"{-V,--verbose}"[Be more verbose]" \
     "(-C --no-cpu-stats)"{-C,--no-cpu-stats}"[Do not print CPU time statistics on exit]" \