ftrace: Pass retval through return in ftrace_dyn_arch_init()

No architecture uses the "data" parameter in ftrace_dyn_arch_init() in any
way, it just sets the value to 0. And this is used as a return value
in the caller -- ftrace_init, which just checks the retval against
zero.

Note there is also "return 0" in every ftrace_dyn_arch_init.  So it is
enough to check the retval and remove all the indirect sets of data on
all archs.

Link: http://lkml.kernel.org/r/1393268401-24379-3-git-send-email-jslaby@suse.cz
Cc: linux-arch@vger.kernel.org
Signed-off-by: Jiri Slaby <jslaby@suse.cz>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>

diff --git a/Documentation/trace/ftrace-design.txt b/Documentation/trace/ftrace-design.txt
index 79fcafc7fd64119c6924625a1faf5a93c04acf8e..117168884023b2945bf21a16fbe88fc811040155 100644 (file)
--- a/Documentation/trace/ftrace-design.txt
+++ b/Documentation/trace/ftrace-design.txt
@@ -360,9 +360,6 @@ function below should be sufficient for most people:
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       /* return value is done indirectly via data */
-       *(unsigned long *)data = 0;
-
        return 0;
 }
 

diff --git a/arch/arm/kernel/ftrace.c b/arch/arm/kernel/ftrace.c
index 34e56647dceeee88d99f65d5fd0a6e00fb46a0fd..5cd0d05edf35f7bc90951a33bd6b81ad12421c3d 100644 (file)
--- a/arch/arm/kernel/ftrace.c
+++ b/arch/arm/kernel/ftrace.c
@@ -158,8 +158,6 @@ int ftrace_make_nop(struct module *mod,
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       *(unsigned long *)data = 0;
-
        return 0;
 }
 #endif /* CONFIG_DYNAMIC_FTRACE */

diff --git a/arch/blackfin/kernel/ftrace.c b/arch/blackfin/kernel/ftrace.c
index 9277905b82cf27efacef0cf5f83bc00af838d7db..f74c5ae6a25be4b29c01b9f070cde140bdc132b8 100644 (file)
--- a/arch/blackfin/kernel/ftrace.c
+++ b/arch/blackfin/kernel/ftrace.c
@@ -67,9 +67,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       /* return value is done indirectly via data */
-       *(unsigned long *)data = 0;
-
        return 0;
 }
 

diff --git a/arch/ia64/kernel/ftrace.c b/arch/ia64/kernel/ftrace.c
index 7fc8c961b1f7f2291b5cc25d1e2a4f7250cc41a3..cfaa93a8bbdf7f2e4b9172de07b0c2457674d296 100644 (file)
--- a/arch/ia64/kernel/ftrace.c
+++ b/arch/ia64/kernel/ftrace.c
@@ -200,7 +200,5 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 /* run from kstop_machine */
 int __init ftrace_dyn_arch_init(void *data)
 {
-       *(unsigned long *)data = 0;
-
        return 0;
 }

diff --git a/arch/metag/kernel/ftrace.c b/arch/metag/kernel/ftrace.c
index a774f321643fd2605ee1387c059185081cc1b93a..bf593932b353677001d023452ecef1efc105d2a8 100644 (file)
--- a/arch/metag/kernel/ftrace.c
+++ b/arch/metag/kernel/ftrace.c
@@ -119,8 +119,5 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 /* run from kstop_machine */
 int __init ftrace_dyn_arch_init(void *data)
 {
-       /* The return code is returned via data */
-       writel(0, data);
-
        return 0;
 }

diff --git a/arch/microblaze/kernel/ftrace.c b/arch/microblaze/kernel/ftrace.c
index e8a5e9cf4ed13c5587b64f836f4915b15de658ed..ffa595c7fec2c0379ba50fcef2af51476019cfca 100644 (file)
--- a/arch/microblaze/kernel/ftrace.c
+++ b/arch/microblaze/kernel/ftrace.c
@@ -173,9 +173,6 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       /* The return code is retured via data */
-       *(unsigned long *)data = 0;
-
        return 0;
 }
 

diff --git a/arch/mips/kernel/ftrace.c b/arch/mips/kernel/ftrace.c
index 185ba258361b979ee9531bd18d38b0242e1de979..013016bec9e1097e393f6c3619129c14bf61d2b0 100644 (file)
--- a/arch/mips/kernel/ftrace.c
+++ b/arch/mips/kernel/ftrace.c
@@ -206,9 +206,6 @@ int __init ftrace_dyn_arch_init(void *data)
        /* Remove "b ftrace_stub" to ensure ftrace_caller() is executed */
        ftrace_modify_code(MCOUNT_ADDR, INSN_NOP);
 
-       /* The return code is retured via data */
-       *(unsigned long *)data = 0;
-
        return 0;
 }
 #endif /* CONFIG_DYNAMIC_FTRACE */

diff --git a/arch/powerpc/kernel/ftrace.c b/arch/powerpc/kernel/ftrace.c
index 9b27b293a9226903c81529a4f01aee64a7f07d23..d059664cdf16a7673e830358391e7e74b6bf6ad2 100644 (file)
--- a/arch/powerpc/kernel/ftrace.c
+++ b/arch/powerpc/kernel/ftrace.c
@@ -533,11 +533,6 @@ void arch_ftrace_update_code(int command)
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       /* caller expects data to be zero */
-       unsigned long *p = data;
-
-       *p = 0;
-
        return 0;
 }
 #endif /* CONFIG_DYNAMIC_FTRACE */

diff --git a/arch/s390/kernel/ftrace.c b/arch/s390/kernel/ftrace.c
index 224db03e95182adc3976aecb3b20f0de5d2b0b13..77b2f3a1f50aa28eefc346e53b3da8f12ac276e1 100644 (file)
--- a/arch/s390/kernel/ftrace.c
+++ b/arch/s390/kernel/ftrace.c
@@ -132,7 +132,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       *(unsigned long *) data = 0;
        return 0;
 }
 

diff --git a/arch/sh/kernel/ftrace.c b/arch/sh/kernel/ftrace.c
index 30e13196d35bf0b96c1367788635b5778464f2ba..493997541d2c6c31d47d478da33be6696f6a7c97 100644 (file)
--- a/arch/sh/kernel/ftrace.c
+++ b/arch/sh/kernel/ftrace.c
@@ -274,9 +274,6 @@ int ftrace_make_call(struct dyn_ftrace *rec, unsigned long addr)
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       /* The return code is retured via data */
-       __raw_writel(0, (unsigned long)data);
-
        return 0;
 }
 #endif /* CONFIG_DYNAMIC_FTRACE */

diff --git a/arch/sparc/kernel/ftrace.c b/arch/sparc/kernel/ftrace.c
index 03ab022e51c5e8378b8ec487b3c896f7e450ee6c..ee813b82da497cc7b4ba3d65558e76e2850c3ced 100644 (file)
--- a/arch/sparc/kernel/ftrace.c
+++ b/arch/sparc/kernel/ftrace.c
@@ -84,10 +84,6 @@ int ftrace_update_ftrace_func(ftrace_func_t func)
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       unsigned long *p = data;
-
-       *p = 0;
-
        return 0;
 }
 #endif

diff --git a/arch/tile/kernel/ftrace.c b/arch/tile/kernel/ftrace.c
index f1c452092eeb0a750dd402bccb003638f0dc73eb..34d9ea0bca9f3bede0aa40ab6c6a309e867e99fb 100644 (file)
--- a/arch/tile/kernel/ftrace.c
+++ b/arch/tile/kernel/ftrace.c
@@ -169,8 +169,6 @@ int ftrace_make_nop(struct module *mod,
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       *(unsigned long *)data = 0;
-
        return 0;
 }
 #endif /* CONFIG_DYNAMIC_FTRACE */

diff --git a/arch/x86/kernel/ftrace.c b/arch/x86/kernel/ftrace.c
index 8cabf638cb6330f2490571ee9ca05286875ec00e..bbe5a5b88aad6e5207282f4dc98c9dbe0b1c2974 100644 (file)
--- a/arch/x86/kernel/ftrace.c
+++ b/arch/x86/kernel/ftrace.c
@@ -670,9 +670,6 @@ void arch_ftrace_update_code(int command)
 
 int __init ftrace_dyn_arch_init(void *data)
 {
-       /* The return code is retured via data */
-       *(unsigned long *)data = 0;
-
        return 0;
 }
 #endif

diff --git a/kernel/trace/ftrace.c b/kernel/trace/ftrace.c
index 76b6ed29d856fb2f732fab97eb53a06ac1483c6a..083c6d5fce25a3faeda8519a4c8acc761eda4a26 100644 (file)
--- a/kernel/trace/ftrace.c
+++ b/kernel/trace/ftrace.c
@@ -4379,11 +4379,9 @@ void __init ftrace_init(void)
        addr = (unsigned long)ftrace_stub;
 
        local_irq_save(flags);
-       ftrace_dyn_arch_init(&addr);
+       ret = ftrace_dyn_arch_init(&addr);
        local_irq_restore(flags);
-
-       /* ftrace_dyn_arch_init places the return code in addr */
-       if (addr)
+       if (ret)
                goto failed;
 
        count = __stop_mcount_loc - __start_mcount_loc;