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@@ -21,9 +21,8 @@ void mcount_replace_code(void);
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void ftrace_disable_code(void);
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void ftrace_enable_insn(void);
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-#ifdef CONFIG_64BIT
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/*
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- * The 64-bit mcount code looks like this:
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+ * The mcount code looks like this:
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* stg %r14,8(%r15) # offset 0
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* larl %r1,<&counter> # offset 6
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* brasl %r14,_mcount # offset 12
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@@ -34,7 +33,7 @@ void ftrace_enable_insn(void);
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* Note: we do not patch the first instruction to an unconditional branch,
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* since that would break kprobes/jprobes. It is easier to leave the larl
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* instruction in and only modify the second instruction.
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- * The 64-bit enabled ftrace code block looks like this:
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+ * The enabled ftrace code block looks like this:
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* larl %r0,.+24 # offset 0
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* > lg %r1,__LC_FTRACE_FUNC # offset 6
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* br %r1 # offset 12
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@@ -71,65 +70,15 @@ asm(
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#define MCOUNT_INSN_OFFSET 6
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#define FTRACE_INSN_SIZE 6
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-#else /* CONFIG_64BIT */
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-/*
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- * The 31-bit mcount code looks like this:
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- * st %r14,4(%r15) # offset 0
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- * > bras %r1,0f # offset 4
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- * > .long _mcount # offset 8
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- * > .long <&counter> # offset 12
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- * > 0: l %r14,0(%r1) # offset 16
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- * > l %r1,4(%r1) # offset 20
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- * basr %r14,%r14 # offset 24
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- * l %r14,4(%r15) # offset 26
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- * Total length is 30 bytes. The twenty bytes starting from offset 4
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- * to offset 24 get overwritten by ftrace_make_nop / ftrace_make_call.
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- * The 31-bit enabled ftrace code block looks like this:
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- * st %r14,4(%r15) # offset 0
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- * > l %r14,__LC_FTRACE_FUNC # offset 4
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- * > j 0f # offset 8
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- * > .fill 12,1,0x07 # offset 12
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- * 0: basr %r14,%r14 # offset 24
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- * l %r14,4(%r14) # offset 26
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- * The return points of the mcount/ftrace function have the same offset 26.
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- * The 31-bit disabled ftrace code block looks like this:
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- * st %r14,4(%r15) # offset 0
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- * > j .+26 # offset 4
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- * > j 0f # offset 8
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- * > .fill 12,1,0x07 # offset 12
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- * 0: basr %r14,%r14 # offset 24
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- * l %r14,4(%r14) # offset 26
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- * The j instruction branches to offset 30 to skip as many instructions
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- * as possible.
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- */
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-asm(
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- " .align 4\n"
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- "ftrace_disable_code:\n"
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- " j 1f\n"
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- " j 0f\n"
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- " .fill 12,1,0x07\n"
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- "0: basr %r14,%r14\n"
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- "1:\n"
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- " .align 4\n"
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- "ftrace_enable_insn:\n"
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- " l %r14,"__stringify(__LC_FTRACE_FUNC)"\n");
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-
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-#define FTRACE_INSN_SIZE 4
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-
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-#endif /* CONFIG_64BIT */
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-
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-#ifdef CONFIG_64BIT
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int ftrace_modify_call(struct dyn_ftrace *rec, unsigned long old_addr,
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unsigned long addr)
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{
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return 0;
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}
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-#endif
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int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
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unsigned long addr)
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{
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-#ifdef CONFIG_64BIT
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/* Initial replacement of the whole mcount block */
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if (addr == MCOUNT_ADDR) {
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if (probe_kernel_write((void *) rec->ip - MCOUNT_INSN_OFFSET,
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@@ -138,7 +87,6 @@ int ftrace_make_nop(struct module *mod, struct dyn_ftrace *rec,
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return -EPERM;
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return 0;
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}
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-#endif
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if (probe_kernel_write((void *) rec->ip, ftrace_disable_code,
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MCOUNT_INSN_SIZE))
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return -EPERM;
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@@ -196,8 +144,6 @@ out:
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* the original offset to prepare_ftrace_return and put it back.
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*/
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-#ifdef CONFIG_64BIT
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-
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int ftrace_enable_ftrace_graph_caller(void)
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{
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static unsigned short offset = 0x0002;
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@@ -216,25 +162,4 @@ int ftrace_disable_ftrace_graph_caller(void)
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&offset, sizeof(offset));
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}
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-#else /* CONFIG_64BIT */
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-
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-int ftrace_enable_ftrace_graph_caller(void)
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-{
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- unsigned short offset;
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-
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- offset = ((void *) prepare_ftrace_return -
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- (void *) ftrace_graph_caller) / 2;
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- return probe_kernel_write((void *) ftrace_graph_caller + 2,
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- &offset, sizeof(offset));
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-}
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-
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-int ftrace_disable_ftrace_graph_caller(void)
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-{
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- static unsigned short offset = 0x0002;
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-
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- return probe_kernel_write((void *) ftrace_graph_caller + 2,
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- &offset, sizeof(offset));
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-}
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-
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-#endif /* CONFIG_64BIT */
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#endif /* CONFIG_FUNCTION_GRAPH_TRACER */
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Heiko Carstens