* [PATCH] x86/platform/uv: avoid unused variable warning
@ 2019-12-12 13:58 Arnd Bergmann
2019-12-12 14:01 ` Arnd Bergmann
2019-12-12 14:54 ` Christoph Hellwig
0 siblings, 2 replies; 5+ messages in thread
From: Arnd Bergmann @ 2019-12-12 13:58 UTC (permalink / raw)
To: Thomas Gleixner, Ingo Molnar, Borislav Petkov, x86, Mike Travis,
Steve Wahl, Dimitri Sivanich
Cc: Arnd Bergmann, Andrew Morton, Christoph Hellwig, H. Peter Anvin,
Hedi Berriche, Justin Ernst, Peter Zijlstra, Russ Anderson,
Anshuman Khandual, linux-kernel
When CONFIG_PROC_FS is disabled, the compiler warns about an
unused variable:
arch/x86/kernel/apic/x2apic_uv_x.c: In function 'uv_setup_proc_files':
arch/x86/kernel/apic/x2apic_uv_x.c:1546:8: error: unused variable 'name' [-Werror=unused-variable]
char *name = hubless ? "hubless" : "hubbed";
Simplify the code so this variable is no longer needed.
Fixes: 8785968bce1c ("x86/platform/uv: Add UV Hubbed/Hubless Proc FS Files")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
arch/x86/kernel/apic/x2apic_uv_x.c | 28 ++++------------------------
1 file changed, 4 insertions(+), 24 deletions(-)
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index d5b51a740524..1af416da1f87 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -1493,13 +1493,13 @@ static void check_efi_reboot(void)
}
/* Setup user proc fs files */
-static int proc_hubbed_show(struct seq_file *file, void *data)
+static int __maybe_unused proc_hubbed_show(struct seq_file *file, void *data)
{
seq_printf(file, "0x%x\n", uv_hubbed_system);
return 0;
}
-static int proc_hubless_show(struct seq_file *file, void *data)
+static int __maybe_unused proc_hubless_show(struct seq_file *file, void *data)
{
seq_printf(file, "0x%x\n", uv_hubless_system);
return 0;
@@ -1511,28 +1511,11 @@ static int proc_oemid_show(struct seq_file *file, void *data)
return 0;
}
-static int proc_hubbed_open(struct inode *inode, struct file *file)
-{
- return single_open(file, proc_hubbed_show, (void *)NULL);
-}
-
-static int proc_hubless_open(struct inode *inode, struct file *file)
-{
- return single_open(file, proc_hubless_show, (void *)NULL);
-}
-
static int proc_oemid_open(struct inode *inode, struct file *file)
{
return single_open(file, proc_oemid_show, (void *)NULL);
}
-/* (struct is "non-const" as open function is set at runtime) */
-static struct file_operations proc_version_fops = {
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
static const struct file_operations proc_oemid_fops = {
.open = proc_oemid_open,
.read = seq_read,
@@ -1543,15 +1526,12 @@ static const struct file_operations proc_oemid_fops = {
static __init void uv_setup_proc_files(int hubless)
{
struct proc_dir_entry *pde;
- char *name = hubless ? "hubless" : "hubbed";
pde = proc_mkdir(UV_PROC_NODE, NULL);
- proc_create("oemid", 0, pde, &proc_oemid_fops);
- proc_create(name, 0, pde, &proc_version_fops);
if (hubless)
- proc_version_fops.open = proc_hubless_open;
+ proc_create_single("hubless", 0, pde, proc_hubless_show);
else
- proc_version_fops.open = proc_hubbed_open;
+ proc_create_single("hubbed", 0, pde, proc_hubbed_show);
}
/* Initialize UV hubless systems */
--
2.20.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
* Re: [PATCH] x86/platform/uv: avoid unused variable warning
2019-12-12 13:58 [PATCH] x86/platform/uv: avoid unused variable warning Arnd Bergmann
@ 2019-12-12 14:01 ` Arnd Bergmann
2019-12-12 14:54 ` Christoph Hellwig
1 sibling, 0 replies; 5+ messages in thread
From: Arnd Bergmann @ 2019-12-12 14:01 UTC (permalink / raw)
To: Thomas Gleixner, Ingo Molnar, Borislav Petkov,
the arch/x86 maintainers, Mike Travis, Steve Wahl,
Dimitri Sivanich
Cc: Andrew Morton, Christoph Hellwig, H. Peter Anvin, Hedi Berriche,
Justin Ernst, Peter Zijlstra, Russ Anderson, Anshuman Khandual,
linux-kernel
On Thu, Dec 12, 2019 at 2:58 PM Arnd Bergmann <arnd@arndb.de> wrote:
>
> When CONFIG_PROC_FS is disabled, the compiler warns about an
> unused variable:
>
> arch/x86/kernel/apic/x2apic_uv_x.c: In function 'uv_setup_proc_files':
> arch/x86/kernel/apic/x2apic_uv_x.c:1546:8: error: unused variable 'name' [-Werror=unused-variable]
> char *name = hubless ? "hubless" : "hubbed";
>
> Simplify the code so this variable is no longer needed.
>
> Fixes: 8785968bce1c ("x86/platform/uv: Add UV Hubbed/Hubless Proc FS Files")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
I noticed a second too late that this loses the oemid procfs file (annoyingly
I did not get a warning because gcc ignores unused static const variables)
Please wait for v2.
Arnd
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] x86/platform/uv: avoid unused variable warning
2019-12-12 13:58 [PATCH] x86/platform/uv: avoid unused variable warning Arnd Bergmann
2019-12-12 14:01 ` Arnd Bergmann
@ 2019-12-12 14:54 ` Christoph Hellwig
2019-12-12 15:16 ` Mike Travis
1 sibling, 1 reply; 5+ messages in thread
From: Christoph Hellwig @ 2019-12-12 14:54 UTC (permalink / raw)
To: Arnd Bergmann
Cc: Thomas Gleixner, Ingo Molnar, Borislav Petkov, x86, Mike Travis,
Steve Wahl, Dimitri Sivanich, Andrew Morton, Christoph Hellwig,
H. Peter Anvin, Hedi Berriche, Justin Ernst, Peter Zijlstra,
Russ Anderson, Anshuman Khandual, linux-kernel
Instead of that maybe_unused mess please just use good old ifdefs.
> if (hubless)
> - proc_version_fops.open = proc_hubless_open;
> + proc_create_single("hubless", 0, pde, proc_hubless_show);
> else
> - proc_version_fops.open = proc_hubbed_open;
> + proc_create_single("hubbed", 0, pde, proc_hubbed_show);
> }
Or someone could figure out what happens if we turn the
proc_create_single stub into an inline function instead of the
define. That makes it used at a syntactic level, the big question is
if the compiler is smart enough to optimize away the unused callback
still.
^ permalink raw reply [flat|nested] 5+ messages in thread
* Re: [PATCH] x86/platform/uv: avoid unused variable warning
2019-12-12 14:54 ` Christoph Hellwig
@ 2019-12-12 15:16 ` Mike Travis
0 siblings, 0 replies; 5+ messages in thread
From: Mike Travis @ 2019-12-12 15:16 UTC (permalink / raw)
To: Christoph Hellwig, Arnd Bergmann
Cc: Thomas Gleixner, Ingo Molnar, Borislav Petkov, x86, Steve Wahl,
Dimitri Sivanich, Andrew Morton, H. Peter Anvin, Hedi Berriche,
Justin Ernst, Peter Zijlstra, Russ Anderson, Anshuman Khandual,
linux-kernel
On 12/12/2019 6:54 AM, Christoph Hellwig wrote:
> Instead of that maybe_unused mess please just use good old ifdefs.
>
>> if (hubless)
>> - proc_version_fops.open = proc_hubless_open;
>> + proc_create_single("hubless", 0, pde, proc_hubless_show);
>> else
>> - proc_version_fops.open = proc_hubbed_open;
>> + proc_create_single("hubbed", 0, pde, proc_hubbed_show);
>> }
>
> Or someone could figure out what happens if we turn the
> proc_create_single stub into an inline function instead of the
> define. That makes it used at a syntactic level, the big question is
> if the compiler is smart enough to optimize away the unused callback
> still.
>
Yes, if CONFIG_PROC_FS is undefined, then this whole section can be
removed since it's sole purpose is to set up the /proc/ interface.
Something like this should suffice:
> ---
> arch/x86/kernel/apic/x2apic_uv_x.c | 9 +++++++++
> 1 file changed, 9 insertions(+)
>
> --- linux.orig/arch/x86/kernel/apic/x2apic_uv_x.c
> +++ linux/arch/x86/kernel/apic/x2apic_uv_x.c
> @@ -1533,6 +1533,7 @@ static void check_efi_reboot(void)
> reboot_type = BOOT_ACPI;
> }
>
> +#ifdef CONFIG_PROC_FS
> /* Setup user proc fs files */
> static int proc_hubbed_show(struct seq_file *file, void *data)
> {
> @@ -1595,6 +1596,14 @@ static __init void uv_setup_proc_files(i
> proc_version_fops.open = proc_hubbed_open;
> }
>
> +#else /* !CONFIG_PROC_FS */
> +
> +static __init void uv_setup_proc_files(int hubless)
> +{
> +}
> +
> +#endif /* !CONFIG_PROC_FS */
> +
> /* Initialize UV hubless systems */
> static __init int uv_system_init_hubless(void)
> {
^ permalink raw reply [flat|nested] 5+ messages in thread
* [PATCH] x86/platform/uv: avoid unused variable warning
@ 2019-12-12 14:03 Arnd Bergmann
0 siblings, 0 replies; 5+ messages in thread
From: Arnd Bergmann @ 2019-12-12 14:03 UTC (permalink / raw)
To: Thomas Gleixner, Ingo Molnar, Borislav Petkov, x86
Cc: Arnd Bergmann, Mike Travis, Steve Wahl, Dimitri Sivanich,
Andrew Morton, Christoph Hellwig, H. Peter Anvin, Hedi Berriche,
Justin Ernst, Peter Zijlstra, Russ Anderson, linux-kernel
When CONFIG_PROC_FS is disabled, the compiler warns about an
unused variable:
arch/x86/kernel/apic/x2apic_uv_x.c: In function 'uv_setup_proc_files':
arch/x86/kernel/apic/x2apic_uv_x.c:1546:8: error: unused variable 'name' [-Werror=unused-variable]
char *name = hubless ? "hubless" : "hubbed";
Simplify the code so this variable is no longer needed.
Fixes: 8785968bce1c ("x86/platform/uv: Add UV Hubbed/Hubless Proc FS Files")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
arch/x86/kernel/apic/x2apic_uv_x.c | 43 +++++-------------------------
1 file changed, 6 insertions(+), 37 deletions(-)
diff --git a/arch/x86/kernel/apic/x2apic_uv_x.c b/arch/x86/kernel/apic/x2apic_uv_x.c
index d5b51a740524..ad53b2abc859 100644
--- a/arch/x86/kernel/apic/x2apic_uv_x.c
+++ b/arch/x86/kernel/apic/x2apic_uv_x.c
@@ -1493,65 +1493,34 @@ static void check_efi_reboot(void)
}
/* Setup user proc fs files */
-static int proc_hubbed_show(struct seq_file *file, void *data)
+static int __maybe_unused proc_hubbed_show(struct seq_file *file, void *data)
{
seq_printf(file, "0x%x\n", uv_hubbed_system);
return 0;
}
-static int proc_hubless_show(struct seq_file *file, void *data)
+static int __maybe_unused proc_hubless_show(struct seq_file *file, void *data)
{
seq_printf(file, "0x%x\n", uv_hubless_system);
return 0;
}
-static int proc_oemid_show(struct seq_file *file, void *data)
+static int __maybe_unused proc_oemid_show(struct seq_file *file, void *data)
{
seq_printf(file, "%s/%s\n", oem_id, oem_table_id);
return 0;
}
-static int proc_hubbed_open(struct inode *inode, struct file *file)
-{
- return single_open(file, proc_hubbed_show, (void *)NULL);
-}
-
-static int proc_hubless_open(struct inode *inode, struct file *file)
-{
- return single_open(file, proc_hubless_show, (void *)NULL);
-}
-
-static int proc_oemid_open(struct inode *inode, struct file *file)
-{
- return single_open(file, proc_oemid_show, (void *)NULL);
-}
-
-/* (struct is "non-const" as open function is set at runtime) */
-static struct file_operations proc_version_fops = {
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
-static const struct file_operations proc_oemid_fops = {
- .open = proc_oemid_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = single_release,
-};
-
static __init void uv_setup_proc_files(int hubless)
{
struct proc_dir_entry *pde;
- char *name = hubless ? "hubless" : "hubbed";
pde = proc_mkdir(UV_PROC_NODE, NULL);
- proc_create("oemid", 0, pde, &proc_oemid_fops);
- proc_create(name, 0, pde, &proc_version_fops);
+ proc_create_single("oemid", 0, pde, proc_oemid_show);
if (hubless)
- proc_version_fops.open = proc_hubless_open;
+ proc_create_single("hubless", 0, pde, proc_hubless_show);
else
- proc_version_fops.open = proc_hubbed_open;
+ proc_create_single("hubbed", 0, pde, proc_hubbed_show);
}
/* Initialize UV hubless systems */
--
2.20.0
^ permalink raw reply related [flat|nested] 5+ messages in thread
end of thread, other threads:[~2019-12-12 15:16 UTC | newest]
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2019-12-12 13:58 [PATCH] x86/platform/uv: avoid unused variable warning Arnd Bergmann
2019-12-12 14:01 ` Arnd Bergmann
2019-12-12 14:54 ` Christoph Hellwig
2019-12-12 15:16 ` Mike Travis
2019-12-12 14:03 Arnd Bergmann
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