diff options
authorBorislav Petkov <borislav.petkov@amd.com>2011-09-21 14:10:43 +0200
committerBorislav Petkov <bp@alien8.de>2012-03-19 12:03:58 +0100
commit5e8e19bf6c3c9d8ecf74e2a7fdae99a76949bdf6 (patch)
parent11b0a31473edf74b70ab6f8fe857b61bff82d7cc (diff)
EDAC: Correct scrub rate API
The original scrub rate API definition states that if scrub rate accessors are not implemented, a negative value (-1) should be written to the sysfs file (/sys/devices/system/edac/mc/mc<N>/sdram_scrub_rate, where N is the memory controller number on the system). This is counter-intuitive and awkward at the very least because, when setting the scrub rate, userspace has to write to sysfs and then read it back to check error status of the operation. As Tony notes, best it would be to not have the sdram_scrub_rate in sysfs if scrub rate support is not implemented. It is too late about that and a bunch of drivers on a bunch of arches would need to be changed and tested which is not a trivial task ATM. Instead, settle for the next best thing of returning -ENODEV when implementation is missing and -EINVAL when there was an error encountered while setting the scrub rate. Reported-by: Han Pingtian <phan@redhat.com> Cc: Tony Luck <tony.luck@intel.com> Link: http://lkml.kernel.org/r/20110916105856.GA13253@hpt.nay.redhat.com Signed-off-by: Borislav Petkov <borislav.petkov@amd.com>
2 files changed, 4 insertions, 4 deletions
diff --git a/Documentation/edac.txt b/Documentation/edac.txt
index 249822cde82b..fdcc49fad8e1 100644
--- a/Documentation/edac.txt
+++ b/Documentation/edac.txt
@@ -334,8 +334,8 @@ Sdram memory scrubbing rate:
Reading the file will return the actual scrubbing rate employed.
- If configuration fails or memory scrubbing is not implemented, the value
- of the attribute file will be -1.
+ If configuration fails or memory scrubbing is not implemented, accessing
+ that attribute will fail.
diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c
index d56e63477d5c..e9a28f576d14 100644
--- a/drivers/edac/edac_mc_sysfs.c
+++ b/drivers/edac/edac_mc_sysfs.c
@@ -452,7 +452,7 @@ static ssize_t mci_sdram_scrub_rate_store(struct mem_ctl_info *mci,
int new_bw = 0;
if (!mci->set_sdram_scrub_rate)
- return -EINVAL;
+ return -ENODEV;
if (strict_strtoul(data, 10, &bandwidth) < 0)
return -EINVAL;
@@ -475,7 +475,7 @@ static ssize_t mci_sdram_scrub_rate_show(struct mem_ctl_info *mci, char *data)
int bandwidth = 0;
if (!mci->get_sdram_scrub_rate)
- return -EINVAL;
+ return -ENODEV;
bandwidth = mci->get_sdram_scrub_rate(mci);
if (bandwidth < 0) {

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