| Message ID | 20210622133923.295373-3-danielhb413@gmail.com (mailing list archive) |
|---|---|
| State | Accepted |
| Headers | show |
| Series | powerpc/pseries: cleanups for dlpar_memory_add* functions | expand |
| Context | Check | Description |
|---|---|---|
| snowpatch_ozlabs/apply_patch | success | Successfully applied on branch powerpc/merge (7f030e9d57b8ff6025bde4162f42378e6081126a) |
| snowpatch_ozlabs/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 44 lines checked |
| snowpatch_ozlabs/needsstable | success | Patch has no Fixes tags |
Le 22/06/2021 à 15:39, Daniel Henrique Barboza a écrit : > After a successful dlpar_add_lmb() call the LMB is marked as reserved. > Later on, depending whether we added enough LMBs or not, we rely on > the marked LMBs to see which ones might need to be removed, and we > remove the reservation of all of them. > > These are done in for_each_drmem_lmb() loops without any break > condition. This means that we're going to check all LMBs of the partition > even after going through all the reserved ones. > > This patch adds break conditions in both loops to avoid this. The > 'lmbs_added' variable was renamed to 'lmbs_reserved', and it's now > being decremented each time a lmb reservation is removed, indicating > if there are still marked LMBs to be processed. Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com> > Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com> > --- > arch/powerpc/platforms/pseries/hotplug-memory.c | 17 ++++++++++++----- > 1 file changed, 12 insertions(+), 5 deletions(-) > > diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c > index 28a7fd90232f..c0a03e1537cb 100644 > --- a/arch/powerpc/platforms/pseries/hotplug-memory.c > +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c > @@ -673,7 +673,7 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) > { > struct drmem_lmb *lmb; > int lmbs_available = 0; > - int lmbs_added = 0; > + int lmbs_reserved = 0; > int rc; > > pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add); > @@ -714,13 +714,12 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) > * requested LMBs cannot be added. > */ > drmem_mark_lmb_reserved(lmb); > - > - lmbs_added++; > - if (lmbs_added == lmbs_to_add) > + lmbs_reserved++; > + if (lmbs_reserved == lmbs_to_add) > break; > } > > - if (lmbs_added != lmbs_to_add) { > + if (lmbs_reserved != lmbs_to_add) { > pr_err("Memory hot-add failed, removing any added LMBs\n"); > > for_each_drmem_lmb(lmb) { > @@ -735,6 +734,10 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) > dlpar_release_drc(lmb->drc_index); > > drmem_remove_lmb_reservation(lmb); > + lmbs_reserved--; > + > + if (lmbs_reserved == 0) > + break; > } > rc = -EINVAL; > } else { > @@ -745,6 +748,10 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) > pr_debug("Memory at %llx (drc index %x) was hot-added\n", > lmb->base_addr, lmb->drc_index); > drmem_remove_lmb_reservation(lmb); > + lmbs_reserved--; > + > + if (lmbs_reserved == 0) > + break; > } > rc = 0; > } >
On Tue, 22 Jun 2021 10:39:22 -0300, Daniel Henrique Barboza wrote: > After a successful dlpar_add_lmb() call the LMB is marked as reserved. > Later on, depending whether we added enough LMBs or not, we rely on > the marked LMBs to see which ones might need to be removed, and we > remove the reservation of all of them. > > These are done in for_each_drmem_lmb() loops without any break > condition. This means that we're going to check all LMBs of the partition > even after going through all the reserved ones. > > [...] Applied to powerpc/next. [2/3] powerpc/pseries: break early in dlpar_memory_add_by_count() loops https://git.kernel.org/powerpc/c/c2aaddcc65b343fad4ed184e625abd3e68f63b9b cheers
diff --git a/arch/powerpc/platforms/pseries/hotplug-memory.c b/arch/powerpc/platforms/pseries/hotplug-memory.c index 28a7fd90232f..c0a03e1537cb 100644 --- a/arch/powerpc/platforms/pseries/hotplug-memory.c +++ b/arch/powerpc/platforms/pseries/hotplug-memory.c @@ -673,7 +673,7 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) { struct drmem_lmb *lmb; int lmbs_available = 0; - int lmbs_added = 0; + int lmbs_reserved = 0; int rc; pr_info("Attempting to hot-add %d LMB(s)\n", lmbs_to_add); @@ -714,13 +714,12 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) * requested LMBs cannot be added. */ drmem_mark_lmb_reserved(lmb); - - lmbs_added++; - if (lmbs_added == lmbs_to_add) + lmbs_reserved++; + if (lmbs_reserved == lmbs_to_add) break; } - if (lmbs_added != lmbs_to_add) { + if (lmbs_reserved != lmbs_to_add) { pr_err("Memory hot-add failed, removing any added LMBs\n"); for_each_drmem_lmb(lmb) { @@ -735,6 +734,10 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) dlpar_release_drc(lmb->drc_index); drmem_remove_lmb_reservation(lmb); + lmbs_reserved--; + + if (lmbs_reserved == 0) + break; } rc = -EINVAL; } else { @@ -745,6 +748,10 @@ static int dlpar_memory_add_by_count(u32 lmbs_to_add) pr_debug("Memory at %llx (drc index %x) was hot-added\n", lmb->base_addr, lmb->drc_index); drmem_remove_lmb_reservation(lmb); + lmbs_reserved--; + + if (lmbs_reserved == 0) + break; } rc = 0; }
After a successful dlpar_add_lmb() call the LMB is marked as reserved. Later on, depending whether we added enough LMBs or not, we rely on the marked LMBs to see which ones might need to be removed, and we remove the reservation of all of them. These are done in for_each_drmem_lmb() loops without any break condition. This means that we're going to check all LMBs of the partition even after going through all the reserved ones. This patch adds break conditions in both loops to avoid this. The 'lmbs_added' variable was renamed to 'lmbs_reserved', and it's now being decremented each time a lmb reservation is removed, indicating if there are still marked LMBs to be processed. Signed-off-by: Daniel Henrique Barboza <danielhb413@gmail.com> --- arch/powerpc/platforms/pseries/hotplug-memory.c | 17 ++++++++++++----- 1 file changed, 12 insertions(+), 5 deletions(-)