Re: [PATCH] rs6000: Retry tbegin. instructions that can fail intermittently

2022-02-16 Thread Segher Boessenkool
On Tue, Feb 15, 2022 at 04:59:45PM -0600, Peter Bergner wrote: > > That is the way any HTM code should be written in the first place > > (except for rollback-only transactions, but let's not go there -- > > besides, it is normal for those to fail as well, and there needs to be a > > fallback there

Re: [PATCH] rs6000: Retry tbegin. instructions that can fail intermittently

2022-02-15 Thread Peter Bergner via Gcc-patches
On 2/15/22 3:54 PM, Segher Boessenkool wrote: > On Tue, Feb 15, 2022 at 01:03:09PM -0600, Peter Bergner wrote: >> The HTM tbegin. instruction can fail intermittently due to many reasons. > > Just a few really. But, if the transaction fails it will appear as if > the tbegin. had an error as well,

Re: [PATCH] rs6000: Retry tbegin. instructions that can fail intermittently

2022-02-15 Thread Segher Boessenkool
Hi! On Tue, Feb 15, 2022 at 01:03:09PM -0600, Peter Bergner wrote: > The HTM tbegin. instruction can fail intermittently due to many reasons. Just a few really. But, if the transaction fails it will appear as if the tbegin. had an error as well, is that what you are seeing? > This can lead to t

[PATCH] rs6000: Retry tbegin. instructions that can fail intermittently

2022-02-15 Thread Peter Bergner via Gcc-patches
The HTM tbegin. instruction can fail intermittently due to many reasons. This can lead to the htm-1.c testsuite test case FAILing from time to time. The solution is to allow retrying the instruction a few times before aborting. Bill has seen this fail a 1-2 times per 1 runs. With the change b