From fb3f3e7fc6d4afb32f9eba32124beaf40313de3c Mon Sep 17 00:00:00 2001 From: Matt Fleming Date: Sun, 16 Aug 2009 15:44:08 +0100 Subject: sh: unwinder: Fix memory leak and create our own kmem cache Plug a memory leak in dwarf_unwinder_dump() where we didn't free the memory that we had previously allocated for the DWARF frames and DWARF registers. Now is also a opportune time to implement our own mempool and kmem cache. It's a good idea to have a certain number of frame and register objects in reserve at all times, so that we are guaranteed to have our allocation satisfied even when memory is scarce. Since we have pools to allocate from we can implement the registers for each frame as a linked list as opposed to a sparsely populated array. Whilst it's true that the lookup time for a linked list is larger than for arrays, there's only usually a maximum of 8 registers per frame. So the overhead isn't that much of a concern. Signed-off-by: Matt Fleming --- arch/sh/include/asm/dwarf.h | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-) (limited to 'arch/sh/include/asm') diff --git a/arch/sh/include/asm/dwarf.h b/arch/sh/include/asm/dwarf.h index 2fbe8720411e..a22fbe98303f 100644 --- a/arch/sh/include/asm/dwarf.h +++ b/arch/sh/include/asm/dwarf.h @@ -265,10 +265,7 @@ struct dwarf_frame { unsigned long pc; - struct dwarf_reg *regs; - unsigned int num_regs; /* how many regs are allocated? */ - - unsigned int depth; /* what level are we in the callstack? */ + struct list_head reg_list; unsigned long cfa; @@ -292,22 +289,15 @@ struct dwarf_frame { * @flags: Describes how to calculate the value of this register */ struct dwarf_reg { + struct list_head link; + + unsigned int number; + unsigned long addr; unsigned long flags; #define DWARF_REG_OFFSET (1 << 0) }; -/** - * dwarf_stack - a DWARF stack contains a collection of DWARF frames - * @depth: the number of frames in the stack - * @level: an array of DWARF frames, indexed by stack level - * - */ -struct dwarf_stack { - unsigned int depth; - struct dwarf_frame **level; -}; - /* * Call Frame instruction opcodes. */ @@ -372,7 +362,7 @@ static inline unsigned int DW_CFA_operand(unsigned long insn) extern struct dwarf_frame *dwarf_unwind_stack(unsigned long, struct dwarf_frame *); -#endif /* __ASSEMBLY__ */ +#endif /* !__ASSEMBLY__ */ #define CFI_STARTPROC .cfi_startproc #define CFI_ENDPROC .cfi_endproc -- cgit v1.2.3