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authorYi Yang <yi.y.yang@intel.com>2008-06-14 00:54:37 -0400
committerAndi Kleen <andi@basil.nowhere.org>2008-07-16 23:27:01 +0200
commit3d532d5e3882c1387a2722df2a368c4a9224b12f (patch)
tree40890690a8b62a86451ef1f66765b69f47a0573f /drivers/acpi/processor_throttling.c
parent6594d87ebd8371f4b67f7ab4b68f172b139b78d6 (diff)
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ACPI: fix processor throttling set error
http://bugzilla.kernel.org/show_bug.cgi?id=9704 When echo some invalid values to /proc/acpi/processor/*/throttling, there isn't any error info returned, on the contray, it sets throttling value to some T* successfully, obviously, this is incorrect, a correct way should be to let it fail and return error info. This patch fixed the aforementioned issue, it also enables /proc/acpi/processor/*/throttling to accept such values as 't0' and 'T0', it also strictly limits /proc/acpi/processor/*/throttling only to accept "*", "t*" and "T*", "*" is the throttling state value the processor can support, current, it is 0 - 7. Before applying this patch, the test result is below: [root@localhost acpi]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T1 state available: T0 to T7 states: T0: 100% *T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost acpi]# echo "1xxxxxx" > /proc/acpi/processor/CPU0/throttling [root@localhost acpi]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T1 state available: T0 to T7 states: T0: 100% *T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost acpi]# echo "0" > /proc/acpi/processor/CPU0/throttling [root@localhost acpi]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost acpi]# cd / [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost /]# echo "T0" > /proc/acpi/processor/CPU0/throttling [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost /]# echo "T7" > /proc/acpi/processor/CPU0/throttling [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost /]# echo "T100" > /proc/acpi/processor/CPU0/throttling [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost /]# echo "xxx" > /proc/acpi/processor/CPU0/throttling [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost /]# echo "2xxxx" > /proc/acpi/processor/CPU0/throttling [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T2 state available: T0 to T7 states: T0: 100% T1: 87% *T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost /]# echo "" > /proc/acpi/processor/CPU0/throttling [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost /]# echo "7777" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost /]# echo "7xxx" > /proc/acpi/processor/CPU0/throttling [root@localhost /]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T7 state available: T0 to T7 states: T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% *T7: 12% [root@localhost /]# After applying this patch, the test result is below: [root@localhost linux-2.6.24-rc6]# echo > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo "" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo "0" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# echo "t0" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# echo "T0" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T0 state available: T0 to T7 states: *T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% T7: 12% [root@localhost linux-2.6.24-rc6]# echo "T7" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T7 state available: T0 to T7 states: T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% *T7: 12% [root@localhost linux-2.6.24-rc6]# echo "T8" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# vi drivers/acpi/processor_throttling.c [root@localhost linux-2.6.24-rc6]# echo "T8" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo "t7" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# echo "t70" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo "70" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo "7000" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo "70" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo "xxx" > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo -n > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# echo -n "" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# echo $? 0 [root@localhost linux-2.6.24-rc6]# echo -n "" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T7 state available: T0 to T7 states: T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% *T7: 12% [root@localhost linux-2.6.24-rc6]# echo -n "" > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# cat /proc/acpi/processor/CPU0/throttling state count: 8 active state: T7 state available: T0 to T7 states: T0: 100% T1: 87% T2: 75% T3: 62% T4: 50% T5: 37% T6: 25% *T7: 12% [root@localhost linux-2.6.24-rc6]# echo t0 > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# echo T0 > /proc/acpi/processor/CPU0/throttling [root@localhost linux-2.6.24-rc6]# echo Tt0 > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# echo T > /proc/acpi/processor/CPU0/throttling -bash: echo: write error: Invalid argument [root@localhost linux-2.6.24-rc6]# Signed-off-by: Yi Yang <yi.y.yang@intel.com> Signed-off-by: Len Brown <len.brown@intel.com> Signed-off-by: Andi Kleen <ak@linux.intel.com>
Diffstat (limited to 'drivers/acpi/processor_throttling.c')
-rw-r--r--drivers/acpi/processor_throttling.c24
1 files changed, 20 insertions, 4 deletions
diff --git a/drivers/acpi/processor_throttling.c b/drivers/acpi/processor_throttling.c
index 8728782aad3b..53345dbc5027 100644
--- a/drivers/acpi/processor_throttling.c
+++ b/drivers/acpi/processor_throttling.c
@@ -1232,7 +1232,10 @@ static ssize_t acpi_processor_write_throttling(struct file *file,
int result = 0;
struct seq_file *m = file->private_data;
struct acpi_processor *pr = m->private;
- char state_string[12] = { '\0' };
+ char state_string[5] = "";
+ char *charp = NULL;
+ size_t state_val = 0;
+ char tmpbuf[5] = "";
if (!pr || (count > sizeof(state_string) - 1))
return -EINVAL;
@@ -1241,10 +1244,23 @@ static ssize_t acpi_processor_write_throttling(struct file *file,
return -EFAULT;
state_string[count] = '\0';
+ if ((count > 0) && (state_string[count-1] == '\n'))
+ state_string[count-1] = '\0';
- result = acpi_processor_set_throttling(pr,
- simple_strtoul(state_string,
- NULL, 0));
+ charp = state_string;
+ if ((state_string[0] == 't') || (state_string[0] == 'T'))
+ charp++;
+
+ state_val = simple_strtoul(charp, NULL, 0);
+ if (state_val >= pr->throttling.state_count)
+ return -EINVAL;
+
+ snprintf(tmpbuf, 5, "%d", state_val);
+
+ if (strcmp(tmpbuf, charp) != 0)
+ return -EINVAL;
+
+ result = acpi_processor_set_throttling(pr, state_val);
if (result)
return result;