AcoSail/kernel_optimize_test
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s390: remove dead code from signal handler

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The code in entry[64].S calls do_signal only on return to user space.
user_mode(regs) is true for every calls to do_signal, it is unnecessary
to recheck user_mode at the start of do_signal and the legacy signal
stack switching path in get_sigframe is never reached.

Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
This commit is contained in:
Martin Schwidefsky 2012-05-04 09:46:04 +02:00
parent a686425b31
commit c15787a7c3
2 changed files with 0 additions and 23 deletions
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7
arch/s390/kernel/compat_signal.c
View File

@ -437,13 +437,6 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
sp = current->sas_ss_sp + current->sas_ss_size;
}
/* This is the legacy signal stack switching. */
else if (!user_mode(regs) &&
!(ka->sa.sa_flags & SA_RESTORER) &&
ka->sa.sa_restorer) {
sp = (unsigned long) ka->sa.sa_restorer;
}
return (void __user *)((sp - frame_size) & -8ul);
}

16
arch/s390/kernel/signal.c
View File

@ -235,13 +235,6 @@ get_sigframe(struct k_sigaction *ka, struct pt_regs * regs, size_t frame_size)
sp = current->sas_ss_sp + current->sas_ss_size;
}
/* This is the legacy signal stack switching. */
else if (!user_mode(regs) &&
!(ka->sa.sa_flags & SA_RESTORER) &&
ka->sa.sa_restorer) {
sp = (unsigned long) ka->sa.sa_restorer;
}
return (void __user *)((sp - frame_size) & -8ul);
}
@ -414,15 +407,6 @@ void do_signal(struct pt_regs *regs)
struct k_sigaction ka;
sigset_t *oldset;
/*
* We want the common case to go fast, which
* is why we may in certain cases get here from
* kernel mode. Just return without doing anything
* if so.
*/
if (!user_mode(regs))
return;
if (test_thread_flag(TIF_RESTORE_SIGMASK))
oldset = &current->saved_sigmask;
else