diff mbox series

[net-next,1/5,V2] eth: fbnic: add locking support for hw stats

Message ID 20250410070859.4160768-2-mohsin.bashr@gmail.com (mailing list archive)
State Accepted
Commit 9f61eb2d185b06d49ef8c25af994d6fc571433cc
Delegated to: Netdev Maintainers
Headers show
Series eth: fbnic: extend hardware stats coverage | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/ynl success Generated files up to date; no warnings/errors; no diff in generated;
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 0 this patch: 0
netdev/build_tools success No tools touched, skip
netdev/cc_maintainers warning 1 maintainers not CCed: suhui@nfschina.com
netdev/build_clang success Errors and warnings before: 0 this patch: 0
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 0 this patch: 0
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 47 lines checked
netdev/build_clang_rust success No Rust files in patch. Skipping build
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0
netdev/contest success net-next-2025-04-11--03-00 (tests: 900)

Commit Message

Mohsin Bashir April 10, 2025, 7:08 a.m. UTC 
This patch adds lock protection for the hardware statistics for fbnic.
The hardware statistics access via ndo_get_stats64 is not protected by
the rtnl_lock(). Since these stats can be accessed from different places
in the code such as service task, ethtool, Q-API, and net_device_ops, a
lock-less approach can lead to races.

Note that this patch is not a fix rather, just a prep for the subsequent
changes in this series.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Mohsin Bashir <mohsin.bashr@gmail.com>
Reviewed-by: Simon Horman <horms@kernel.org>
---
 drivers/net/ethernet/meta/fbnic/fbnic.h          |  3 +++
 drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c | 16 +++++++++++++---
 drivers/net/ethernet/meta/fbnic/fbnic_pci.c      |  1 +
 3 files changed, 17 insertions(+), 3 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/meta/fbnic/fbnic.h b/drivers/net/ethernet/meta/fbnic/fbnic.h
index 4ca7b99ef131..80d54edaac55 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic.h
+++ b/drivers/net/ethernet/meta/fbnic/fbnic.h
@@ -81,6 +81,9 @@  struct fbnic_dev {
 
 	/* Local copy of hardware statistics */
 	struct fbnic_hw_stats hw_stats;
+
+	/* Lock protecting access to hw_stats */
+	spinlock_t hw_stats_lock;
 };
 
 /* Reserve entry 0 in the MSI-X "others" array until we have filled all
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
index 89ac6bc8c7fc..957138cb841e 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_hw_stats.c
@@ -203,18 +203,28 @@  static void fbnic_get_pcie_stats_asic64(struct fbnic_dev *fbd,
 
 void fbnic_reset_hw_stats(struct fbnic_dev *fbd)
 {
+	spin_lock(&fbd->hw_stats_lock);
 	fbnic_reset_rpc_stats(fbd, &fbd->hw_stats.rpc);
 	fbnic_reset_pcie_stats_asic(fbd, &fbd->hw_stats.pcie);
+	spin_unlock(&fbd->hw_stats_lock);
 }
 
-void fbnic_get_hw_stats32(struct fbnic_dev *fbd)
+static void __fbnic_get_hw_stats32(struct fbnic_dev *fbd)
 {
 	fbnic_get_rpc_stats32(fbd, &fbd->hw_stats.rpc);
 }
 
-void fbnic_get_hw_stats(struct fbnic_dev *fbd)
+void fbnic_get_hw_stats32(struct fbnic_dev *fbd)
 {
-	fbnic_get_hw_stats32(fbd);
+	spin_lock(&fbd->hw_stats_lock);
+	__fbnic_get_hw_stats32(fbd);
+	spin_unlock(&fbd->hw_stats_lock);
+}
 
+void fbnic_get_hw_stats(struct fbnic_dev *fbd)
+{
+	spin_lock(&fbd->hw_stats_lock);
+	__fbnic_get_hw_stats32(fbd);
 	fbnic_get_pcie_stats_asic64(fbd, &fbd->hw_stats.pcie);
+	spin_unlock(&fbd->hw_stats_lock);
 }
diff --git a/drivers/net/ethernet/meta/fbnic/fbnic_pci.c b/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
index 6cbbc2ee3e1f..1f76ebdd6ad1 100644
--- a/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
+++ b/drivers/net/ethernet/meta/fbnic/fbnic_pci.c
@@ -292,6 +292,7 @@  static int fbnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
 
 	fbnic_devlink_register(fbd);
 	fbnic_dbg_fbd_init(fbd);
+	spin_lock_init(&fbd->hw_stats_lock);
 
 	/* Capture snapshot of hardware stats so netdev can calculate delta */
 	fbnic_reset_hw_stats(fbd);