linux-kernel - [PATCH 2/2] USB: xhci: use urb hcpriv mempool for private data

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-Id: <20250513055545.5738-1-00107082@163.com>
Date: Tue, 13 May 2025 13:55:45 +0800
From: David Wang <00107082@....com>
To: mathias.nyman@...el.com,
	gregkh@...uxfoundation.org
Cc: stern@...land.harvard.edu,
	linux-usb@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	David Wang <00107082@....com>
Subject: [PATCH 2/2] USB: xhci: use urb hcpriv mempool for private data

xhci keeps alloc/free private data for each enqueue/dequeue cycles,
when using a USB webcam, the memory allocation frequency could reach
about 1k/s.

URB objects have longer lifecycle than private data, hand over ownership
of private data to urb can save lots of memory allocations over time.

Signed-off-by: David Wang <00107082@....com>
---
 drivers/usb/host/xhci-ring.c | 1 -
 drivers/usb/host/xhci.c      | 5 +----
 2 files changed, 1 insertion(+), 5 deletions(-)

diff --git a/drivers/usb/host/xhci-ring.c b/drivers/usb/host/xhci-ring.c
index 423bf3649570..b98e5211693d 100644
--- a/drivers/usb/host/xhci-ring.c
+++ b/drivers/usb/host/xhci-ring.c
@@ -831,7 +831,6 @@ static void xhci_giveback_urb_in_irq(struct xhci_hcd *xhci,
 				usb_amd_quirk_pll_enable();
 		}
 	}
-	xhci_urb_free_priv(urb_priv);
 	usb_hcd_unlink_urb_from_ep(hcd, urb);
 	trace_xhci_urb_giveback(urb);
 	usb_hcd_giveback_urb(hcd, urb, status);
diff --git a/drivers/usb/host/xhci.c b/drivers/usb/host/xhci.c
index 90eb491267b5..94ff5fa9dcf2 100644
--- a/drivers/usb/host/xhci.c
+++ b/drivers/usb/host/xhci.c
@@ -1552,7 +1552,7 @@ static int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag
 	else
 		num_tds = 1;
 
-	urb_priv = kzalloc(struct_size(urb_priv, td, num_tds), mem_flags);
+	urb_priv = urb_hcpriv_mempool_zalloc(urb, struct_size(urb_priv, td, num_tds));
 	if (!urb_priv)
 		return -ENOMEM;
 
@@ -1626,7 +1626,6 @@ static int xhci_urb_enqueue(struct usb_hcd *hcd, struct urb *urb, gfp_t mem_flag
 
 	if (ret) {
 free_priv:
-		xhci_urb_free_priv(urb_priv);
 		urb->hcpriv = NULL;
 	}
 	spin_unlock_irqrestore(&xhci->lock, flags);
@@ -1789,8 +1788,6 @@ static int xhci_urb_dequeue(struct usb_hcd *hcd, struct urb *urb, int status)
 	return ret;
 
 err_giveback:
-	if (urb_priv)
-		xhci_urb_free_priv(urb_priv);
 	usb_hcd_unlink_urb_from_ep(hcd, urb);
 	spin_unlock_irqrestore(&xhci->lock, flags);
 	usb_hcd_giveback_urb(hcd, urb, -ESHUTDOWN);
-- 
2.39.2