e1000: fix stack size

Here's the patch. It shrinks the stack from 1152 bytes to 192 bytes (the
first version, that only did the e1000_option part, got it down to 600
bytes). About half comes from not using multiple "e1000_option"
structures, the other half comes from turning the "e1000_opt_list[]"
arrays into "static const" instead, so that gcc doesn't copy them onto the
stack.

Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Reveiewed-by: Auke Kok <auke-jan.h.kok@intel.com>
Tested-by: Emil Tantilov <emil.s.tantilov@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 45 insertions, 36 deletions

diff --git a/drivers/net/e1000/e1000_param.c b/drivers/net/e1000/e1000_param.c
index b9f90a5d3d4d..213437d13154 100644
--- a/drivers/net/e1000/e1000_param.c
+++ b/drivers/net/e1000/e1000_param.c
@@ -208,7 +208,7 @@ struct e1000_option {
                 } r;
                 struct { /* list_option info */
                         int nr;
-                        struct e1000_opt_list { int i; char *str; } *p;
+                        const struct e1000_opt_list { int i; char *str; } *p;
                 } l;
         } arg;
 };
@@ -242,7 +242,7 @@ static int __devinit e1000_validate_option(unsigned int *value,
                 break;
         case list_option: {
                 int i;
-                struct e1000_opt_list *ent;
+                const struct e1000_opt_list *ent;
 
                 for (i = 0; i < opt->arg.l.nr; i++) {
                         ent = &opt->arg.l.p[i];
@@ -279,7 +279,9 @@ static void e1000_check_copper_options(struct e1000_adapter *adapter);
 
 void __devinit e1000_check_options(struct e1000_adapter *adapter)
 {
+        struct e1000_option opt;
         int bd = adapter->bd_number;
+
         if (bd >= E1000_MAX_NIC) {
                 DPRINTK(PROBE, NOTICE,
                        "Warning: no configuration for board #%i\n", bd);
@@ -287,19 +289,21 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
         }
 
         { /* Transmit Descriptor Count */
-                struct e1000_option opt = {
+                struct e1000_tx_ring *tx_ring = adapter->tx_ring;
+                int i;
+                e1000_mac_type mac_type = adapter->hw.mac_type;
+
+                opt = (struct e1000_option) {
                         .type = range_option,
                         .name = "Transmit Descriptors",
                         .err  = "using default of "
                                 __MODULE_STRING(E1000_DEFAULT_TXD),
                         .def  = E1000_DEFAULT_TXD,
-                        .arg  = { .r = { .min = E1000_MIN_TXD }}
+                        .arg  = { .r = {
+                                .min = E1000_MIN_TXD,
+                                .max = mac_type < e1000_82544 ? E1000_MAX_TXD : E1000_MAX_82544_TXD
+                                }}
                 };
-                struct e1000_tx_ring *tx_ring = adapter->tx_ring;
-                int i;
-                e1000_mac_type mac_type = adapter->hw.mac_type;
-                opt.arg.r.max = mac_type < e1000_82544 ?
-                        E1000_MAX_TXD : E1000_MAX_82544_TXD;
 
                 if (num_TxDescriptors > bd) {
                         tx_ring->count = TxDescriptors[bd];
@@ -313,19 +317,21 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                         tx_ring[i].count = tx_ring->count;
         }
         { /* Receive Descriptor Count */
-                struct e1000_option opt = {
+                struct e1000_rx_ring *rx_ring = adapter->rx_ring;
+                int i;
+                e1000_mac_type mac_type = adapter->hw.mac_type;
+
+                opt = (struct e1000_option) {
                         .type = range_option,
                         .name = "Receive Descriptors",
                         .err  = "using default of "
                                 __MODULE_STRING(E1000_DEFAULT_RXD),
                         .def  = E1000_DEFAULT_RXD,
-                        .arg  = { .r = { .min = E1000_MIN_RXD }}
+                        .arg  = { .r = {
+                                .min = E1000_MIN_RXD,
+                                .max = mac_type < e1000_82544 ? E1000_MAX_RXD : E1000_MAX_82544_RXD
+                        }}
                 };
-                struct e1000_rx_ring *rx_ring = adapter->rx_ring;
-                int i;
-                e1000_mac_type mac_type = adapter->hw.mac_type;
-                opt.arg.r.max = mac_type < e1000_82544 ? E1000_MAX_RXD :
-                        E1000_MAX_82544_RXD;
 
                 if (num_RxDescriptors > bd) {
                         rx_ring->count = RxDescriptors[bd];
@@ -339,7 +345,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                         rx_ring[i].count = rx_ring->count;
         }
         { /* Checksum Offload Enable/Disable */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = enable_option,
                         .name = "Checksum Offload",
                         .err  = "defaulting to Enabled",
@@ -363,7 +369,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                          { E1000_FC_FULL,    "Flow Control Enabled" },
                          { E1000_FC_DEFAULT, "Flow Control Hardware Default" }};
 
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = list_option,
                         .name = "Flow Control",
                         .err  = "reading default settings from EEPROM",
@@ -381,7 +387,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Transmit Interrupt Delay */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = range_option,
                         .name = "Transmit Interrupt Delay",
                         .err  = "using default of " __MODULE_STRING(DEFAULT_TIDV),
@@ -399,7 +405,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Transmit Absolute Interrupt Delay */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = range_option,
                         .name = "Transmit Absolute Interrupt Delay",
                         .err  = "using default of " __MODULE_STRING(DEFAULT_TADV),
@@ -417,7 +423,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Receive Interrupt Delay */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = range_option,
                         .name = "Receive Interrupt Delay",
                         .err  = "using default of " __MODULE_STRING(DEFAULT_RDTR),
@@ -435,7 +441,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Receive Absolute Interrupt Delay */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = range_option,
                         .name = "Receive Absolute Interrupt Delay",
                         .err  = "using default of " __MODULE_STRING(DEFAULT_RADV),
@@ -453,7 +459,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Interrupt Throttling Rate */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = range_option,
                         .name = "Interrupt Throttling Rate (ints/sec)",
                         .err  = "using default of " __MODULE_STRING(DEFAULT_ITR),
@@ -497,7 +503,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Smart Power Down */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = enable_option,
                         .name = "PHY Smart Power Down",
                         .err  = "defaulting to Disabled",
@@ -513,7 +519,7 @@ void __devinit e1000_check_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Kumeran Lock Loss Workaround */
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = enable_option,
                         .name = "Kumeran Lock Loss Workaround",
                         .err  = "defaulting to Enabled",
@@ -578,16 +584,18 @@ static void __devinit e1000_check_fiber_options(struct e1000_adapter *adapter)
 
 static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
 {
+        struct e1000_option opt;
         unsigned int speed, dplx, an;
         int bd = adapter->bd_number;
 
         { /* Speed */
-                struct e1000_opt_list speed_list[] = {{          0, "" },
-                                                      {   SPEED_10, "" },
-                                                      {  SPEED_100, "" },
-                                                      { SPEED_1000, "" }};
+                static const struct e1000_opt_list speed_list[] = {
+                        {          0, "" },
+                        {   SPEED_10, "" },
+                        {  SPEED_100, "" },
+                        { SPEED_1000, "" }};
 
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = list_option,
                         .name = "Speed",
                         .err  = "parameter ignored",
@@ -604,11 +612,12 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
                 }
         }
         { /* Duplex */
-                struct e1000_opt_list dplx_list[] = {{           0, "" },
-                                                     { HALF_DUPLEX, "" },
-                                                     { FULL_DUPLEX, "" }};
+                static const struct e1000_opt_list dplx_list[] = {
+                        {           0, "" },
+                        { HALF_DUPLEX, "" },
+                        { FULL_DUPLEX, "" }};
 
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = list_option,
                         .name = "Duplex",
                         .err  = "parameter ignored",
@@ -637,7 +646,7 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
                        "parameter ignored\n");
                 adapter->hw.autoneg_advertised = AUTONEG_ADV_DEFAULT;
         } else { /* Autoneg */
-                struct e1000_opt_list an_list[] =
+                static const struct e1000_opt_list an_list[] =
                         #define AA "AutoNeg advertising "
                         {{ 0x01, AA "10/HD" },
                          { 0x02, AA "10/FD" },
@@ -671,7 +680,7 @@ static void __devinit e1000_check_copper_options(struct e1000_adapter *adapter)
                          { 0x2e, AA "1000/FD, 100/FD, 100/HD, 10/FD" },
                          { 0x2f, AA "1000/FD, 100/FD, 100/HD, 10/FD, 10/HD" }};
 
-                struct e1000_option opt = {
+                opt = (struct e1000_option) {
                         .type = list_option,
                         .name = "AutoNeg",
                         .err  = "parameter ignored",