Commit 33b16568 authored by Arnd Bergmann's avatar Arnd Bergmann Committed by Jeff Kirsher
Browse files

i40e: reduce stack usage in i40e_set_fc 



The functions i40e_aq_get_phy_abilities_resp() and i40e_set_fc() both
have giant structure on the stack, which makes each one use stack frames
larger than 500 bytes.

As clang decides one function into the other, we get a warning for
exceeding the frame size limit on 32-bit architectures:

drivers/net/ethernet/intel/i40e/i40e_common.c:1654:23: error: stack frame size of 1116 bytes in function 'i40e_set_fc' [-Werror,-Wframe-larger-than=]

When building with gcc, the inlining does not happen, but i40e_set_fc()
calls i40e_aq_get_phy_abilities_resp() anyway, so they add up on the
kernel stack just as much.

The parts that actually use large stacks don't overlap, so make sure
each one is a separate function, and mark them as noinline_for_stack to
prevent the compilers from combining them again.

Fixes: 0a862b43 ("i40e/i40evf: Add module_types and update_link_info")
Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
Tested-by: default avatarAndrew Bowers <andrewx.bowers@intel.com>
Signed-off-by: default avatarJeff Kirsher <jeffrey.t.kirsher@intel.com>
parent c76c9925

drivers/net/ethernet/intel/i40e/i40e_common.c

+51 −40
Original line number Diff line number Diff line
@@ -1643,25 +1643,15 @@ enum i40e_status_code i40e_aq_set_phy_config(struct i40e_hw *hw, 
	return status;

}



/**

 * i40e_set_fc

 * @hw: pointer to the hw struct

 * @aq_failures: buffer to return AdminQ failure information

 * @atomic_restart: whether to enable atomic link restart

 *

 * Set the requested flow control mode using set_phy_config.

 **/

enum i40e_status_code i40e_set_fc(struct i40e_hw *hw, u8 *aq_failures,

static noinline_for_stack enum i40e_status_code

i40e_set_fc_status(struct i40e_hw *hw,

		   struct i40e_aq_get_phy_abilities_resp *abilities,

		   bool atomic_restart)

{

	enum i40e_fc_mode fc_mode = hw->fc.requested_mode;

	struct i40e_aq_get_phy_abilities_resp abilities;

	struct i40e_aq_set_phy_config config;

	enum i40e_status_code status;

	enum i40e_fc_mode fc_mode = hw->fc.requested_mode;

	u8 pause_mask = 0x0;



	*aq_failures = 0x0;



	switch (fc_mode) {

	case I40E_FC_FULL:

		pause_mask |= I40E_AQ_PHY_FLAG_PAUSE_TX;
@@ -1677,39 +1667,60 @@ enum i40e_status_code i40e_set_fc(struct i40e_hw *hw, u8 *aq_failures, 
		break;

	}



	/* Get the current phy config */

	status = i40e_aq_get_phy_capabilities(hw, false, false, &abilities,

					      NULL);

	if (status) {

		*aq_failures |= I40E_SET_FC_AQ_FAIL_GET;

		return status;

	}



	memset(&config, 0, sizeof(struct i40e_aq_set_phy_config));

	/* clear the old pause settings */

	config.abilities = abilities.abilities & ~(I40E_AQ_PHY_FLAG_PAUSE_TX) &

	config.abilities = abilities->abilities & ~(I40E_AQ_PHY_FLAG_PAUSE_TX) &

			   ~(I40E_AQ_PHY_FLAG_PAUSE_RX);

	/* set the new abilities */

	config.abilities |= pause_mask;

	/* If the abilities have changed, then set the new config */

	if (config.abilities != abilities.abilities) {

	if (config.abilities == abilities->abilities)

		return 0;



	/* Auto restart link so settings take effect */

	if (atomic_restart)

		config.abilities |= I40E_AQ_PHY_ENABLE_ATOMIC_LINK;

	/* Copy over all the old settings */

		config.phy_type = abilities.phy_type;

		config.phy_type_ext = abilities.phy_type_ext;

		config.link_speed = abilities.link_speed;

		config.eee_capability = abilities.eee_capability;

		config.eeer = abilities.eeer_val;

		config.low_power_ctrl = abilities.d3_lpan;

		config.fec_config = abilities.fec_cfg_curr_mod_ext_info &

	config.phy_type = abilities->phy_type;

	config.phy_type_ext = abilities->phy_type_ext;

	config.link_speed = abilities->link_speed;

	config.eee_capability = abilities->eee_capability;

	config.eeer = abilities->eeer_val;

	config.low_power_ctrl = abilities->d3_lpan;

	config.fec_config = abilities->fec_cfg_curr_mod_ext_info &

			    I40E_AQ_PHY_FEC_CONFIG_MASK;

		status = i40e_aq_set_phy_config(hw, &config, NULL);



	return i40e_aq_set_phy_config(hw, &config, NULL);

}



/**

 * i40e_set_fc

 * @hw: pointer to the hw struct

 * @aq_failures: buffer to return AdminQ failure information

 * @atomic_restart: whether to enable atomic link restart

 *

 * Set the requested flow control mode using set_phy_config.

 **/

enum i40e_status_code i40e_set_fc(struct i40e_hw *hw, u8 *aq_failures,

				  bool atomic_restart)

{

	struct i40e_aq_get_phy_abilities_resp abilities;

	enum i40e_status_code status;



	*aq_failures = 0x0;



	/* Get the current phy config */

	status = i40e_aq_get_phy_capabilities(hw, false, false, &abilities,

					      NULL);

	if (status) {

		*aq_failures |= I40E_SET_FC_AQ_FAIL_GET;

		return status;

	}



	status = i40e_set_fc_status(hw, &abilities, atomic_restart);

	if (status)

		*aq_failures |= I40E_SET_FC_AQ_FAIL_SET;

	}



	/* Update the link info */

	status = i40e_update_link_info(hw);

	if (status) {
@@ -2537,7 +2548,7 @@ i40e_status i40e_get_link_status(struct i40e_hw *hw, bool *link_up) 
 * i40e_updatelink_status - update status of the HW network link

 * @hw: pointer to the hw struct

 **/

i40e_status i40e_update_link_info(struct i40e_hw *hw)

noinline_for_stack i40e_status i40e_update_link_info(struct i40e_hw *hw)

{

	struct i40e_aq_get_phy_abilities_resp abilities;

	i40e_status status = 0;