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author | Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com> | 2006-06-26 00:25:27 -0700 |
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committer | Linus Torvalds <torvalds@g5.osdl.org> | 2006-06-26 09:58:22 -0700 |
commit | d98f8f05188b45168db43df8ddc9feeb0b1cd512 (patch) | |
tree | 505edc88aa4e8ec3593d7a218c470e7cb9640fb7 /arch/sparc64/mm | |
parent | 4f9e87c0454059e80f3811f95ad9f40ed28c69a2 (diff) | |
download | linux-d98f8f05188b45168db43df8ddc9feeb0b1cd512.tar.bz2 |
[PATCH] Notify page fault call chain for sparc64
Overloading of page fault notification with the notify_die() has performance
issues(since the only interested components for page fault is kprobes and/or
kdb) and hence this patch introduces the new notifier call chain exclusively
for page fault notifications their by avoiding notifying unnecessary
components in the do_page_fault() code path.
Signed-off-by: Anil S Keshavamurthy <anil.s.keshavamurthy@intel.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Diffstat (limited to 'arch/sparc64/mm')
-rw-r--r-- | arch/sparc64/mm/fault.c | 36 |
1 files changed, 35 insertions, 1 deletions
diff --git a/arch/sparc64/mm/fault.c b/arch/sparc64/mm/fault.c index 6e002aacb961..1605967cce91 100644 --- a/arch/sparc64/mm/fault.c +++ b/arch/sparc64/mm/fault.c @@ -31,6 +31,40 @@ #include <asm/kdebug.h> #include <asm/mmu_context.h> +#ifdef CONFIG_KPROBES +ATOMIC_NOTIFIER_HEAD(notify_page_fault_chain); + +/* Hook to register for page fault notifications */ +int register_page_fault_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_register(¬ify_page_fault_chain, nb); +} + +int unregister_page_fault_notifier(struct notifier_block *nb) +{ + return atomic_notifier_chain_unregister(¬ify_page_fault_chain, nb); +} + +static inline int notify_page_fault(enum die_val val, const char *str, + struct pt_regs *regs, long err, int trap, int sig) +{ + struct die_args args = { + .regs = regs, + .str = str, + .err = err, + .trapnr = trap, + .signr = sig + }; + return atomic_notifier_call_chain(¬ify_page_fault_chain, val, &args); +} +#else +static inline int notify_page_fault(enum die_val val, const char *str, + struct pt_regs *regs, long err, int trap, int sig) +{ + return NOTIFY_DONE; +} +#endif + /* * To debug kernel to catch accesses to certain virtual/physical addresses. * Mode = 0 selects physical watchpoints, mode = 1 selects virtual watchpoints. @@ -263,7 +297,7 @@ asmlinkage void __kprobes do_sparc64_fault(struct pt_regs *regs) fault_code = get_thread_fault_code(); - if (notify_die(DIE_PAGE_FAULT, "page_fault", regs, + if (notify_page_fault(DIE_PAGE_FAULT, "page_fault", regs, fault_code, 0, SIGSEGV) == NOTIFY_STOP) return; |