diff options
| author | Chris Zankel <chris@zankel.net> | 2013-02-23 19:35:57 -0800 |
|---|---|---|
| committer | Chris Zankel <chris@zankel.net> | 2013-02-23 19:35:57 -0800 |
| commit | c50842df47970eab459f13490c152aac85fc02f2 (patch) | |
| tree | d2933b4d9641067002ba6d662b0abf6ee3011375 /arch/xtensa/kernel/signal.c | |
| parent | b0c438e642699f8c47b84de957f30cf586cdbebd (diff) | |
xtensa: add support for TLS
The Xtensa architecture provides a global register called THREADPTR
for the purpose of Thread Local Storage (TLS) support. This allows us
to use a fairly simple implementation, keeping the thread pointer in
the regset and simply saving and restoring it upon entering/exiting
the from user space.
Signed-off-by: Chris Zankel <chris@zankel.net>
Diffstat (limited to 'arch/xtensa/kernel/signal.c')
| -rw-r--r-- | arch/xtensa/kernel/signal.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c index de34d6be91cd..6952d8959236 100644 --- a/arch/xtensa/kernel/signal.c +++ b/arch/xtensa/kernel/signal.c @@ -337,7 +337,7 @@ static int setup_frame(int sig, struct k_sigaction *ka, siginfo_t *info, struct rt_sigframe *frame; int err = 0; int signal; - unsigned long sp, ra; + unsigned long sp, ra, tp; sp = regs->areg[1]; @@ -395,7 +395,8 @@ static int setup_frame(int sig, struct k_sigaction *ka, siginfo_t *info, * Return context not modified until this point. */ - /* Set up registers for signal handler */ + /* Set up registers for signal handler; preserve the threadptr */ + tp = regs->threadptr; start_thread(regs, (unsigned long) ka->sa.sa_handler, (unsigned long) frame); @@ -406,6 +407,7 @@ static int setup_frame(int sig, struct k_sigaction *ka, siginfo_t *info, regs->areg[6] = (unsigned long) signal; regs->areg[7] = (unsigned long) &frame->info; regs->areg[8] = (unsigned long) &frame->uc; + regs->threadptr = tp; /* Set access mode to USER_DS. Nomenclature is outdated, but * functionality is used in uaccess.h |