On 10/23/2011 6:20 AM, Jonas Bonn wrote:

Manipulating task state to effect re-execution of an interrupted syscall
used to be purely architecture specific code.  However, as most arch's
were essentially just making minor adjustments to almost identical logic,
this code could be moved to a common implementation.

The generic variant introduces the function handle_syscall_restart() to be
called after get_signal_to_deliver().  The architecture specific register
manipulations required to effect the actual restart are now implemented
in the generic syscall interface found in asm/syscall.h

This patch transitions this architecture's signal handling code over to
using the generic syscall restart code by:

i)  Implementing the register manipulations in asm/syscall.h
ii) Replacing the restart logic with a call to handle_syscall_restart

Cc: Chris Metcalf <redacted>
Signed-off-by: Jonas Bonn <jonas@southpole.se>

I like the idea, though the patch isn't quite right:

- You need to move the definition of INT_SWINT_1_SIGRETURN from
<asm/sigframe.h> to <asm/syscall.h>.  You then have to add #includes of
<asm/syscall.h> to signal.c and stack.c in arch/tile/kernel.  (And probably
use syscall_clear() in signal.c.)

- In syscall_do_restartblock() you need to use regs->regs[], not regs->gprs[].

-- 
Chris Metcalf, Tilera Corp.
http://www.tilera.com