[PATCH v2 10/10] EDAC/mc: Remove per layer counters

[Robert Richter]

Looking at how mci->{ue,ce}_per_layer[EDAC_MAX_LAYERS] is used, it
turns out that only the leaves in the memory hierarchy are consumed
(in sysfs), but not the intermediate layers, e.g.:

 count = dimm->mci->ce_per_layer[dimm->mci->n_layers-1][dimm->idx];

These unused counters only add complexity, remove them. The error
counter values are directly stored in struct dimm_info now.

Signed-off-by: Robert Richter <rrichter@xxxxxxxxxxx>
---
 drivers/edac/edac_mc.c       | 65 +++++++++---------------------------
 drivers/edac/edac_mc_sysfs.c | 20 +++++------
 include/linux/edac.h         |  4 ++-
 3 files changed, 26 insertions(+), 63 deletions(-)

diff --git a/drivers/edac/edac_mc.c b/drivers/edac/edac_mc.c
index 5ea834fceb50..3d43b9fe8171 100644
--- a/drivers/edac/edac_mc.c
+++ b/drivers/edac/edac_mc.c
@@ -445,11 +445,9 @@ struct mem_ctl_info *edac_mc_alloc(unsigned int mc_num,
 {
 	struct mem_ctl_info *mci;
 	struct edac_mc_layer *layer;
-	u32 *ce_per_layer[EDAC_MAX_LAYERS], *ue_per_layer[EDAC_MAX_LAYERS];
-	unsigned int idx, size, tot_dimms = 1, count = 1;
-	unsigned int tot_csrows = 1, tot_channels = 1, tot_errcount = 0;
+	unsigned int idx, size, tot_dimms = 1;
+	unsigned int tot_csrows = 1, tot_channels = 1;
 	void *pvt, *ptr = NULL;
-	int i;
 	bool per_rank = false;
 
 	if (WARN_ON(n_layers > EDAC_MAX_LAYERS || n_layers == 0))
@@ -476,19 +474,10 @@ struct mem_ctl_info *edac_mc_alloc(unsigned int mc_num,
 	 * stringent as what the compiler would provide if we could simply
 	 * hardcode everything into a single struct.
 	 */
-	mci = edac_align_ptr(&ptr, sizeof(*mci), 1);
-	layer = edac_align_ptr(&ptr, sizeof(*layer), n_layers);
-	for (i = 0; i < n_layers; i++) {
-		count *= layers[i].size;
-		edac_dbg(4, "errcount layer %d size %d\n", i, count);
-		ce_per_layer[i] = edac_align_ptr(&ptr, sizeof(u32), count);
-		ue_per_layer[i] = edac_align_ptr(&ptr, sizeof(u32), count);
-		tot_errcount += 2 * count;
-	}
-
-	edac_dbg(4, "allocating %d error counters\n", tot_errcount);
-	pvt = edac_align_ptr(&ptr, sz_pvt, 1);
-	size = ((unsigned long)pvt) + sz_pvt;
+	mci	= edac_align_ptr(&ptr, sizeof(*mci), 1);
+	layer	= edac_align_ptr(&ptr, sizeof(*layer), n_layers);
+	pvt	= edac_align_ptr(&ptr, sz_pvt, 1);
+	size	= ((unsigned long)pvt) + sz_pvt;
 
 	edac_dbg(1, "allocating %u bytes for mci data (%d %s, %d csrows/channels)\n",
 		 size,
@@ -504,10 +493,6 @@ struct mem_ctl_info *edac_mc_alloc(unsigned int mc_num,
 	 * rather than an imaginary chunk of memory located at address 0.
 	 */
 	layer = (struct edac_mc_layer *)(((char *)mci) + ((unsigned long)layer));
-	for (i = 0; i < n_layers; i++) {
-		mci->ce_per_layer[i] = (u32 *)((char *)mci + ((unsigned long)ce_per_layer[i]));
-		mci->ue_per_layer[i] = (u32 *)((char *)mci + ((unsigned long)ue_per_layer[i]));
-	}
 	pvt = sz_pvt ? (((char *)mci) + ((unsigned long)pvt)) : NULL;
 
 	/* setup index and various internal pointers */
@@ -949,48 +934,28 @@ static void edac_inc_ce_error(struct edac_raw_error_desc *e)
 {
 	struct mem_ctl_info *mci = error_desc_to_mci(e);
 	int pos[EDAC_MAX_LAYERS] = { e->top_layer, e->mid_layer, e->low_layer };
-	int i, index = 0;
+	struct dimm_info *dimm = edac_get_dimm(mci, pos[0], pos[1], pos[2]);
 
 	mci->ce_mc += e->error_count;
 
-	if (pos[0] < 0) {
+	if (dimm)
+		dimm->ce_count += e->error_count;
+	else
 		mci->ce_noinfo_count += e->error_count;
-		return;
-	}
-
-	for (i = 0; i < mci->n_layers; i++) {
-		if (pos[i] < 0)
-			break;
-		index += pos[i];
-		mci->ce_per_layer[i][index] += e->error_count;
-
-		if (i < mci->n_layers - 1)
-			index *= mci->layers[i + 1].size;
-	}
 }
 
 static void edac_inc_ue_error(struct edac_raw_error_desc *e)
 {
 	struct mem_ctl_info *mci = error_desc_to_mci(e);
 	int pos[EDAC_MAX_LAYERS] = { e->top_layer, e->mid_layer, e->low_layer };
-	int i, index = 0;
+	struct dimm_info *dimm = edac_get_dimm(mci, pos[0], pos[1], pos[2]);
 
 	mci->ue_mc += e->error_count;
 
-	if (pos[0] < 0) {
+	if (dimm)
+		dimm->ue_count += e->error_count;
+	else
 		mci->ue_noinfo_count += e->error_count;
-		return;
-	}
-
-	for (i = 0; i < mci->n_layers; i++) {
-		if (pos[i] < 0)
-			break;
-		index += pos[i];
-		mci->ue_per_layer[i][index] += e->error_count;
-
-		if (i < mci->n_layers - 1)
-			index *= mci->layers[i + 1].size;
-	}
 }
 
 static void edac_ce_error(struct edac_raw_error_desc *e)
@@ -1137,7 +1102,7 @@ void edac_mc_handle_error(const enum hw_event_mc_err_type type,
 	/*
 	 * Check if the event report is consistent and if the memory
 	 * location is known. If it is known, the DIMM(s) label info
-	 * will be filled and the per-layer error counters will be
+	 * will be filled and the DIMM's error counters will be
 	 * incremented.
 	 */
 	for (i = 0; i < mci->n_layers; i++) {
diff --git a/drivers/edac/edac_mc_sysfs.c b/drivers/edac/edac_mc_sysfs.c
index 0367554e7437..8682df2f7f4f 100644
--- a/drivers/edac/edac_mc_sysfs.c
+++ b/drivers/edac/edac_mc_sysfs.c
@@ -556,10 +556,8 @@ static ssize_t dimmdev_ce_count_show(struct device *dev,
 				      char *data)
 {
 	struct dimm_info *dimm = to_dimm(dev);
-	u32 count;
 
-	count = dimm->mci->ce_per_layer[dimm->mci->n_layers-1][dimm->idx];
-	return sprintf(data, "%u\n", count);
+	return sprintf(data, "%u\n", dimm->ce_count);
 }
 
 static ssize_t dimmdev_ue_count_show(struct device *dev,
@@ -567,10 +565,8 @@ static ssize_t dimmdev_ue_count_show(struct device *dev,
 				      char *data)
 {
 	struct dimm_info *dimm = to_dimm(dev);
-	u32 count;
 
-	count = dimm->mci->ue_per_layer[dimm->mci->n_layers-1][dimm->idx];
-	return sprintf(data, "%u\n", count);
+	return sprintf(data, "%u\n", dimm->ue_count);
 }
 
 /* dimm/rank attribute files */
@@ -666,7 +662,9 @@ static ssize_t mci_reset_counters_store(struct device *dev,
 					const char *data, size_t count)
 {
 	struct mem_ctl_info *mci = to_mci(dev);
-	int cnt, row, chan, i;
+	struct dimm_info *dimm;
+	int row, chan;
+
 	mci->ue_mc = 0;
 	mci->ce_mc = 0;
 	mci->ue_noinfo_count = 0;
@@ -682,11 +680,9 @@ static ssize_t mci_reset_counters_store(struct device *dev,
 			ri->channels[chan]->ce_count = 0;
 	}
 
-	cnt = 1;
-	for (i = 0; i < mci->n_layers; i++) {
-		cnt *= mci->layers[i].size;
-		memset(mci->ce_per_layer[i], 0, cnt * sizeof(u32));
-		memset(mci->ue_per_layer[i], 0, cnt * sizeof(u32));
+	mci_for_each_dimm(mci, dimm) {
+		dimm->ue_count = 0;
+		dimm->ce_count = 0;
 	}
 
 	mci->start_time = jiffies;
diff --git a/include/linux/edac.h b/include/linux/edac.h
index 815f246e0abd..0f20b986b0ab 100644
--- a/include/linux/edac.h
+++ b/include/linux/edac.h
@@ -383,6 +383,9 @@ struct dimm_info {
 	unsigned int csrow, cschannel;	/* Points to the old API data */
 
 	u16 smbios_handle;              /* Handle for SMBIOS type 17 */
+
+	u32 ce_count;
+	u32 ue_count;
 };
 
 /**
@@ -559,7 +562,6 @@ struct mem_ctl_info {
 	 */
 	u32 ce_noinfo_count, ue_noinfo_count;
 	u32 ue_mc, ce_mc;
-	u32 *ce_per_layer[EDAC_MAX_LAYERS], *ue_per_layer[EDAC_MAX_LAYERS];
 
 	struct completion complete;
 
-- 
2.20.1