usbip: dump the port status difference
PATCH 2/3 usbip: dump the port status difference
From: Márton Németh <[email protected]>
At the beginning of vhci_hub_control() function the port status is saved to show what are the differences between the previous and the new status. Change the dump function to really show the differences in the status bit changes: put a '+' sign before the symbolic name of a bit where a bit was set, a '-' sign where the bit was cleared and a SPACE where the bit was not changed. This is similar to the way "diff -u" shows the changes and easy to understand.
--- drivers/staging/usbip/vhci_hcd.c | 20 ++++++++++++++------ 1 files changed, 14 insertions(+), 6 deletions(-)
drivers/staging/usbip/vhci_hcd.c +14 -6
@@ -92,14 +92,22 @@ static const char * const bit_desc[] = { "R31", /*31*/ }; -static void dump_port_status (u32 status) +static void dump_port_status_diff (u32 prev_status,u32 new_status) {int i =0 ; -pr_debug ("status %08x:" , status); +pr_debug ("status %08x -> %08x:" , prev_status, new_status);for (i =0 ; i <32 ; i++) { -if (status & (1 << i)) -pr_debug (" %s" , bit_desc[i]); +if (!(prev_status & (1 << i)) && + new_status & (1 << i)) { +pr_debug (" +%s" , bit_desc[i]); + }else if (prev_status & (1 << i) && + !(new_status & (1 << i))) { +pr_debug (" -%s" , bit_desc[i]); + }else if (prev_status & (1 << i) && + new_status & (1 << i)) { +pr_debug (" %s" , bit_desc[i]); + } }pr_debug ("\n" ); }
@@ -466,8 +474,8 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,pr_debug ("port %d\n" , rhport);/* Only dump valid port status */ if (0 <= rhport) { -dump_port_status (prev_port_status[rhport]); -dump_port_status (dum->port_status[rhport]); +dump_port_status_diff (prev_port_status[rhport], + dum->port_status[rhport]); } }usbip_dbg_vhci_rh (" bye\n" );
Signature · 1 line
1.7.2.5
From: Márton Németh <[email protected]>
At the beginning of vhci_hub_control() function the port status is saved to show what are the differences between the previous and the new status. Change the dump function to really show the differences in the status bit changes: put a '+' sign before the symbolic name of a bit where a bit was set, a '-' sign where the bit was cleared and a SPACE where the bit was not changed. This is similar to the way "diff -u" shows the changes and easy to understand.
--- drivers/staging/usbip/vhci_hcd.c | 20 ++++++++++++++------ 1 files changed, 14 insertions(+), 6 deletions(-)
drivers/staging/usbip/vhci_hcd.c +14 -6
@@ -92,14 +92,22 @@ static const char * const bit_desc[] = { "R31", /*31*/ }; -static void dump_port_status (u32 status) +static void dump_port_status_diff (u32 prev_status,u32 new_status) {int i =0 ; -pr_debug ("status %08x:" , status); +pr_debug ("status %08x -> %08x:" , prev_status, new_status);for (i =0 ; i <32 ; i++) { -if (status & (1 << i)) -pr_debug (" %s" , bit_desc[i]); +if (!(prev_status & (1 << i)) && + new_status & (1 << i)) { +pr_debug (" +%s" , bit_desc[i]); + }else if (prev_status & (1 << i) && + !(new_status & (1 << i))) { +pr_debug (" -%s" , bit_desc[i]); + }else if (prev_status & (1 << i) && + new_status & (1 << i)) { +pr_debug (" %s" , bit_desc[i]); + } }pr_debug ("\n" ); }
@@ -466,8 +474,8 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,pr_debug ("port %d\n" , rhport);/* Only dump valid port status */ if (rhport >=0 ) { -dump_port_status (prev_port_status[rhport]); -dump_port_status (dum->port_status[rhport]); +dump_port_status_diff (prev_port_status[rhport], + dum->port_status[rhport]); } }usbip_dbg_vhci_rh (" bye\n" );
--
1.7.2.5
Quoted 15 lines · Németh Márton
From: Márton Németh <[email protected]>
Change the dump function to
really show the differences in the status bit changesdrivers/staging/usbip/vhci_hcd.c +4
-3+static void dump_port_status_diff (u32 prev_status,u32 new_status) {int i =0 ; -pr_debug ("status %08x:" , status); +pr_debug ("status %08x -> %08x:" , prev_status, new_status);for (i =0 ; i <32 ; i++) { -if (status & (1 << i)) -pr_debug (" %s" , bit_desc[i]); +if (!(prev_status & (1 << i)) && + new_status & (1 << i)) {
drivers/staging/usbip/vhci_hcd.c static const char * const bit_desc[] = { · line 112
Quoted 10 lines
drivers/staging/usbip/vhci_hcd.c +8
-0+pr_debug (" +%s" , bit_desc[i]); + }else if (prev_status & (1 << i) && + !(new_status & (1 << i))) { +pr_debug (" -%s" , bit_desc[i]); + }else if (prev_status & (1 << i) && + new_status & (1 << i)) { +pr_debug (" %s" , bit_desc[i]); + } }pr_debug ("\n" );
trivia:
I think the output isn't quite what you might expect. It could be interleaved by pr_cont from a different thread.
I think this might be a bit more readable as below and this doesn't use implicit newlines by successive pr_<level>.
static void dump_port_status_diff(u32 old_status, u32 new_status)
{
int i = 0;
u32 bit = 1;
char change;
pr_debug("status old->new %08x -> %08x\n", old_status, new_status);
while (bit) {
u32 old = old_status & bit;
u32 new = new_status & bit;
char change;
if (!old && new)
change = '+';
else if (old && !new)
change = '-';
else
change = ' ';
if (old || new)
pr_debug(" %c%s\n", change, bit_desc[i]);
bit <<= 1;
i++; }
}
I don't know if this is in any sort of fast-path or if gcc will completely optimize this completely away if pr_debug isn't declared, but maybe surround the function implementation with
static void dump_port_status_diff(u32 prev_status, u32 new_status) {
#ifdef DEBUG ...
#endif
}
From: Márton Németh <[email protected]>
At the beginning of vhci_hub_control() function the port status is saved to show what are the differences between the previous and the new status. Change the dump function to really show the differences in the status bit changes: put a '+' sign before the symbolic name of a bit where a bit was set, a '-' sign where the bit was cleared and a SPACE where the bit was not changed. This is similar to the way "diff -u" shows the changes and easy to understand.
---
--- drivers/staging/usbip/vhci_hcd.c | 30 ++++++++++++++++++++++-------- 1 files changed, 22 insertions(+), 8 deletions(-)
drivers/staging/usbip/vhci_hcd.c +22 -8
@@ -92,14 +92,28 @@ static const char * const bit_desc[] = { "R31", /*31*/ }; -static void dump_port_status (u32 status) +static void dump_port_status_diff (u32 prev_status,u32 new_status) {int i =0 ; - -pr_debug ("status %08x:" , status); -for (i =0 ; i <32 ; i++) { -if (status & (1 << i)) -pr_debug (" %s" , bit_desc[i]); +u32 bit =1 ; + +pr_debug ("status prev -> new: %08x -> %08x\n" , prev_status, new_status); +while (bit) { +u32 prev = prev_status & bit; +u32 new = new_status & bit; +char change; + +if (!prev && new) + change ='+' ; +else if (prev && !new) + change ='-' ; +else + change =' ' ; + +if (prev || new) +pr_debug (" %c%s\n" , change, bit_desc[i]); + bit <<=1 ; + i++; }pr_debug ("\n" ); }
@@ -466,8 +480,8 @@ static int vhci_hub_control(struct usb_hcd *hcd, u16 typeReq, u16 wValue,pr_debug ("port %d\n" , rhport);/* Only dump valid port status */ if (rhport >=0 ) { -dump_port_status (prev_port_status[rhport]); -dump_port_status (dum->port_status[rhport]); +dump_port_status_diff (prev_port_status[rhport], + dum->port_status[rhport]); } }usbip_dbg_vhci_rh (" bye\n" );
Signature · 1 line
1.7.2.5