[PATCH 1/3] e1000e: Remove redundant runtime resume for ethtool_ops

Bjorn Helgaas
2024-03-25T22:30:01Z

From: Bjorn Helgaas <bhelgaas@google.com>

e60b22c5b7e5 ("e1000e: fix accessing to suspended device") added
ethtool_ops.begin() and .complete(), which used pm_runtime_get_sync() to
resume suspended devices before any ethtool_ops callback and allow suspend
after it completed.

3ef672ab1862 ("e1000e: ethtool unnecessarily takes device out of RPM
suspend") removed ethtool_ops.begin() and .complete() and instead did
pm_runtime_get_sync() only in the individual ethtool_ops callbacks that
access device registers.

Subsequently, f32a21376573 ("ethtool: runtime-resume netdev parent before
ethtool ioctl ops") added pm_runtime_get_sync() in the dev_ethtool() path,
so the device is resumed before *any* ethtool_ops callback, as it was
before 3ef672ab1862.

Remove most runtime resumes from ethtool_ops, which are now redundant
because the resume has already been done by dev_ethtool(). This is
essentially a revert of 3ef672ab1862 ("e1000e: ethtool unnecessarily takes
device out of RPM suspend").

There are a couple subtleties:

- Prior to 3ef672ab1862, the device was resumed only for the duration of
a single ethtool callback. 3ef672ab1862 changed e1000_set_phys_id() so
the device was resumed for ETHTOOL_ID_ACTIVE and remained resumed until
a subsequent callback for ETHTOOL_ID_INACTIVE. Preserve that part of
3ef672ab1862 so the device will not be runtime suspended while in the
ETHTOOL_ID_ACTIVE state.

- 3ef672ab1862 added "if (!pm_runtime_suspended())" in before reading the
STATUS register in e1000_get_settings(). This was racy and is now
unnecessary because dev_ethtool() has resumed the device already, so
revert that.

Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
---
drivers/net/ethernet/intel/e1000e/ethtool.c | 62 ++-------------------
1 file changed, 6 insertions(+), 56 deletions(-)

diff --git a/drivers/net/ethernet/intel/e1000e/ethtool.c b/drivers/net/ethernet/intel/e1000e/ethtool.c
index dc553c51d79a..85da20778e0f 100644
--- a/drivers/net/ethernet/intel/e1000e/ethtool.c
+++ b/drivers/net/ethernet/intel/e1000e/ethtool.c
@@ -156,7 +156,7 @@ static int e1000_get_link_ksettings(struct net_device *netdev,
speed = adapter->link_speed;
cmd->base.duplex = adapter->link_duplex - 1;
}
- } else if (!pm_runtime_suspended(netdev->dev.parent)) {
+ } else {
u32 status = er32(STATUS);

if (status & E1000_STATUS_LU) {
@@ -274,16 +274,13 @@ static int e1000_set_link_ksettings(struct net_device *netdev,
ethtool_convert_link_mode_to_legacy_u32(&advertising,
cmd->link_modes.advertising);

- pm_runtime_get_sync(netdev->dev.parent);
-
/* When SoL/IDER sessions are active, autoneg/speed/duplex
* cannot be changed
*/
if (hw->phy.ops.check_reset_block &&
hw->phy.ops.check_reset_block(hw)) {
e_err("Cannot change link characteristics when SoL/IDER is active.\n");
- ret_val = -EINVAL;
- goto out;
+ return -EINVAL;
}

/* MDI setting is only allowed when autoneg enabled because
@@ -291,16 +288,13 @@ static int e1000_set_link_ksettings(struct net_device *netdev,
* duplex is forced.
*/
if (cmd->base.eth_tp_mdix_ctrl) {
- if (hw->phy.media_type != e1000_media_type_copper) {
- ret_val = -EOPNOTSUPP;
- goto out;
- }
+ if (hw->phy.media_type != e1000_media_type_copper)
+ return -EOPNOTSUPP;

if ((cmd->base.eth_tp_mdix_ctrl != ETH_TP_MDI_AUTO) &&
(cmd->base.autoneg != AUTONEG_ENABLE)) {
e_err("forcing MDI/MDI-X state is not supported when link speed and/or duplex are forced\n");
- ret_val = -EINVAL;
- goto out;
+ return -EINVAL;
}
}

@@ -347,7 +341,6 @@ static int e1000_set_link_ksettings(struct net_device *netdev,
}

out:
- pm_runtime_put_sync(netdev->dev.parent);
clear_bit(__E1000_RESETTING, &adapter->state);
return ret_val;
}
@@ -383,8 +376,6 @@ static int e1000_set_pauseparam(struct net_device *netdev,
while (test_and_set_bit(__E1000_RESETTING, &adapter->state))
usleep_range(1000, 2000);

- pm_runtime_get_sync(netdev->dev.parent);
-
if (adapter->fc_autoneg == AUTONEG_ENABLE) {
hw->fc.requested_mode = e1000_fc_default;
if (netif_running(adapter->netdev)) {
@@ -417,7 +408,6 @@ static int e1000_set_pauseparam(struct net_device *netdev,
}

out:
- pm_runtime_put_sync(netdev->dev.parent);
clear_bit(__E1000_RESETTING, &adapter->state);
return retval;
}
@@ -448,8 +438,6 @@ static void e1000_get_regs(struct net_device *netdev,
u32 *regs_buff = p;
u16 phy_data;

- pm_runtime_get_sync(netdev->dev.parent);
-
memset(p, 0, E1000_REGS_LEN * sizeof(u32));

regs->version = (1u << 24) |
@@ -495,8 +483,6 @@ static void e1000_get_regs(struct net_device *netdev,
e1e_rphy(hw, MII_STAT1000, &phy_data);
regs_buff[24] = (u32)phy_data; /* phy local receiver status */
regs_buff[25] = regs_buff[24]; /* phy remote receiver status */
-
- pm_runtime_put_sync(netdev->dev.parent);
}

static int e1000_get_eeprom_len(struct net_device *netdev)
@@ -529,8 +515,6 @@ static int e1000_get_eeprom(struct net_device *netdev,
if (!eeprom_buff)
return -ENOMEM;

- pm_runtime_get_sync(netdev->dev.parent);
-
if (hw->nvm.type == e1000_nvm_eeprom_spi) {
ret_val = e1000_read_nvm(hw, first_word,
last_word - first_word + 1,
@@ -544,8 +528,6 @@ static int e1000_get_eeprom(struct net_device *netdev,
}
}

- pm_runtime_put_sync(netdev->dev.parent);
-
if (ret_val) {
/* a read error occurred, throw away the result */
memset(eeprom_buff, 0xff, sizeof(u16) *
@@ -595,8 +577,6 @@ static int e1000_set_eeprom(struct net_device *netdev,

ptr = (void *)eeprom_buff;

- pm_runtime_get_sync(netdev->dev.parent);
-
if (eeprom->offset & 1) {
/* need read/modify/write of first changed EEPROM word */
/* only the second byte of the word is being modified */
@@ -637,7 +617,6 @@ static int e1000_set_eeprom(struct net_device *netdev,
ret_val = e1000e_update_nvm_checksum(hw);

out:
- pm_runtime_put_sync(netdev->dev.parent);
kfree(eeprom_buff);
return ret_val;
}
@@ -733,8 +712,6 @@ static int e1000_set_ringparam(struct net_device *netdev,
}
}

- pm_runtime_get_sync(netdev->dev.parent);
-
e1000e_down(adapter, true);

/* We can't just free everything and then setup again, because the
@@ -773,7 +750,6 @@ static int e1000_set_ringparam(struct net_device *netdev,
e1000e_free_tx_resources(temp_tx);
err_setup:
e1000e_up(adapter);
- pm_runtime_put_sync(netdev->dev.parent);
free_temp:
vfree(temp_tx);
vfree(temp_rx);
@@ -1816,8 +1792,6 @@ static void e1000_diag_test(struct net_device *netdev,
u8 autoneg;
bool if_running = netif_running(netdev);

- pm_runtime_get_sync(netdev->dev.parent);
-
set_bit(__E1000_TESTING, &adapter->state);

if (!if_running) {
@@ -1903,8 +1877,6 @@ static void e1000_diag_test(struct net_device *netdev,
}

msleep_interruptible(4 * 1000);
-
- pm_runtime_put_sync(netdev->dev.parent);
}

static void e1000_get_wol(struct net_device *netdev,
@@ -2046,15 +2018,11 @@ static int e1000_set_coalesce(struct net_device *netdev,
adapter->itr_setting = adapter->itr & ~3;
}

- pm_runtime_get_sync(netdev->dev.parent);
-
if (adapter->itr_setting != 0)
e1000e_write_itr(adapter, adapter->itr);
else
e1000e_write_itr(adapter, 0);

- pm_runtime_put_sync(netdev->dev.parent);
-
return 0;
}

@@ -2068,9 +2036,7 @@ static int e1000_nway_reset(struct net_device *netdev)
if (!adapter->hw.mac.autoneg)
return -EINVAL;

- pm_runtime_get_sync(netdev->dev.parent);
e1000e_reinit_locked(adapter);
- pm_runtime_put_sync(netdev->dev.parent);

return 0;
}
@@ -2084,12 +2050,8 @@ static void e1000_get_ethtool_stats(struct net_device *netdev,
int i;
char *p = NULL;

- pm_runtime_get_sync(netdev->dev.parent);
-
dev_get_stats(netdev, &net_stats);

- pm_runtime_put_sync(netdev->dev.parent);
-
for (i = 0; i < E1000_GLOBAL_STATS_LEN; i++) {
switch (e1000_gstrings_stats[i].type) {
case NETDEV_STATS:
@@ -2146,9 +2108,7 @@ static int e1000_get_rxnfc(struct net_device *netdev,
struct e1000_hw *hw = &adapter->hw;
u32 mrqc;

- pm_runtime_get_sync(netdev->dev.parent);
mrqc = er32(MRQC);
- pm_runtime_put_sync(netdev->dev.parent);

if (!(mrqc & E1000_MRQC_RSS_FIELD_MASK))
return 0;
@@ -2211,13 +2171,9 @@ static int e1000e_get_eee(struct net_device *netdev, struct ethtool_keee *edata)
return -EOPNOTSUPP;
}

- pm_runtime_get_sync(netdev->dev.parent);
-
ret_val = hw->phy.ops.acquire(hw);
- if (ret_val) {
- pm_runtime_put_sync(netdev->dev.parent);
+ if (ret_val)
return -EBUSY;
- }

/* EEE Capability */
ret_val = e1000_read_emi_reg_locked(hw, cap_addr, &phy_data);
@@ -2257,8 +2213,6 @@ static int e1000e_get_eee(struct net_device *netdev, struct ethtool_keee *edata)
if (ret_val)
ret_val = -ENODATA;

- pm_runtime_put_sync(netdev->dev.parent);
-
return ret_val;
}

@@ -2299,16 +2253,12 @@ static int e1000e_set_eee(struct net_device *netdev, struct ethtool_keee *edata)

hw->dev_spec.ich8lan.eee_disable = !edata->eee_enabled;

- pm_runtime_get_sync(netdev->dev.parent);
-
/* reset the link */
if (netif_running(netdev))
e1000e_reinit_locked(adapter);
else
e1000e_reset(adapter);

- pm_runtime_put_sync(netdev->dev.parent);
-
return 0;
}

--
2.34.1