diff options
author | Tony Luck <tony.luck@intel.com> | 2016-04-15 14:50:32 -0700 |
---|---|---|
committer | Borislav Petkov <bp@suse.de> | 2016-04-23 14:02:02 +0200 |
commit | ad08c4e97485694fee5ebb181983514facedbb19 (patch) | |
tree | 4c4d834458440c9371c5c01bbc342299aebb7a2b /drivers/edac | |
parent | ab67b6c22d8506b060a66ed0ce1a3e14e3b075e4 (diff) |
EDAC, sb_edac: Remove double buffering of error records
In the bad old days the functions from x86_mce_decoder_chain could be
called in machine check context. So we used to carefully copy them and
defer processing until later. But in
f29a7aff4bd60 ("x86/mce: Avoid potential deadlock due to printk() in MCE context")
we switched the logging code to save the record in a genpool, and call
the functions that registered to be notified later from a work queue.
So drop all the double buffering and do all the work we want to do as
soon as sbridge_mce_check_error() is called.
Signed-off-by: Tony Luck <tony.luck@intel.com>
Cc: Aristeu Rozanski <arozansk@redhat.com>
Cc: Mauro Carvalho Chehab <mchehab@osg.samsung.com>
Cc: linux-edac <linux-edac@vger.kernel.org>
Cc: patrickg@supermicro.com
Link: http://lkml.kernel.org/r/100025611cd780d9bca72792b2b2146760da53e0.1460756761.git.tony.luck@intel.com
Signed-off-by: Borislav Petkov <bp@suse.de>
Diffstat (limited to 'drivers/edac')
-rw-r--r-- | drivers/edac/sb_edac.c | 88 |
1 files changed, 3 insertions, 85 deletions
diff --git a/drivers/edac/sb_edac.c b/drivers/edac/sb_edac.c index 93f0d4120289..342167496626 100644 --- a/drivers/edac/sb_edac.c +++ b/drivers/edac/sb_edac.c @@ -363,16 +363,6 @@ struct sbridge_pvt { /* Memory type detection */ bool is_mirrored, is_lockstep, is_close_pg; - /* Fifo double buffers */ - struct mce mce_entry[MCE_LOG_LEN]; - struct mce mce_outentry[MCE_LOG_LEN]; - - /* Fifo in/out counters */ - unsigned mce_in, mce_out; - - /* Count indicator to show errors not got */ - unsigned mce_overrun; - /* Memory description */ u64 tolm, tohm; struct knl_pvt knl; @@ -3075,63 +3065,8 @@ err_parsing: } /* - * sbridge_check_error Retrieve and process errors reported by the - * hardware. Called by the Core module. - */ -static void sbridge_check_error(struct mem_ctl_info *mci) -{ - struct sbridge_pvt *pvt = mci->pvt_info; - int i; - unsigned count = 0; - struct mce *m; - - /* - * MCE first step: Copy all mce errors into a temporary buffer - * We use a double buffering here, to reduce the risk of - * loosing an error. - */ - smp_rmb(); - count = (pvt->mce_out + MCE_LOG_LEN - pvt->mce_in) - % MCE_LOG_LEN; - if (!count) - return; - - m = pvt->mce_outentry; - if (pvt->mce_in + count > MCE_LOG_LEN) { - unsigned l = MCE_LOG_LEN - pvt->mce_in; - - memcpy(m, &pvt->mce_entry[pvt->mce_in], sizeof(*m) * l); - smp_wmb(); - pvt->mce_in = 0; - count -= l; - m += l; - } - memcpy(m, &pvt->mce_entry[pvt->mce_in], sizeof(*m) * count); - smp_wmb(); - pvt->mce_in += count; - - smp_rmb(); - if (pvt->mce_overrun) { - sbridge_printk(KERN_ERR, "Lost %d memory errors\n", - pvt->mce_overrun); - smp_wmb(); - pvt->mce_overrun = 0; - } - - /* - * MCE second step: parse errors and display - */ - for (i = 0; i < count; i++) - sbridge_mce_output_error(mci, &pvt->mce_outentry[i]); -} - -/* - * sbridge_mce_check_error Replicates mcelog routine to get errors - * This routine simply queues mcelog errors, and - * return. The error itself should be handled later - * by sbridge_check_error. - * WARNING: As this routine should be called at NMI time, extra care should - * be taken to avoid deadlocks, and to be as fast as possible. + * Check that logging is enabled and that this is the right type + * of error for us to handle. */ static int sbridge_mce_check_error(struct notifier_block *nb, unsigned long val, void *data) @@ -3176,21 +3111,7 @@ static int sbridge_mce_check_error(struct notifier_block *nb, unsigned long val, "%u APIC %x\n", mce->cpuvendor, mce->cpuid, mce->time, mce->socketid, mce->apicid); - smp_rmb(); - if ((pvt->mce_out + 1) % MCE_LOG_LEN == pvt->mce_in) { - smp_wmb(); - pvt->mce_overrun++; - return NOTIFY_DONE; - } - - /* Copy memory error at the ringbuffer */ - memcpy(&pvt->mce_entry[pvt->mce_out], mce, sizeof(*mce)); - smp_wmb(); - pvt->mce_out = (pvt->mce_out + 1) % MCE_LOG_LEN; - - /* Handle fatal errors immediately */ - if (mce->mcgstatus & 1) - sbridge_check_error(mci); + sbridge_mce_output_error(mci, mce); /* Advice mcelog that the error were handled */ return NOTIFY_STOP; @@ -3276,9 +3197,6 @@ static int sbridge_register_mci(struct sbridge_dev *sbridge_dev, enum type type) mci->dev_name = pci_name(pdev); mci->ctl_page_to_phys = NULL; - /* Set the function pointer to an actual operation function */ - mci->edac_check = sbridge_check_error; - pvt->info.type = type; switch (type) { case IVY_BRIDGE: |