<html><head><meta http-equiv="Content-Type" content="text/html; charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;" class=""><br class=""><div><br class=""><blockquote type="cite" class=""><div class="">On 07-Jul-2020, at 12:47 PM, Michael Neuling <<a href="mailto:mikey@neuling.org" class="">mikey@neuling.org</a>> wrote:</div><br class="Apple-interchange-newline"><div class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">On Wed, 2020-07-01 at 05:20 -0400, Athira Rajeev wrote:</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">PowerISA v3.1 has few updates for the Branch History Rolling Buffer(BHRB).<br class="">First is the addition of BHRB disable bit and second new filtering<br class="">modes for BHRB.<br class=""><br class="">BHRB disable is controlled via Monitor Mode Control Register A (MMCRA)<br class="">bit 26, namely "BHRB Recording Disable (BHRBRD)". This field controls<br class="">whether BHRB entries are written when BHRB recording is enabled by other<br class="">bits. Patch implements support for this BHRB disable bit.<br class=""></blockquote><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Probably good to note here that this is backwards compatible. So if you have a</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">kernel that doesn't know about this bit, it'll clear it and hence you still get</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">BHRB.<span class="Apple-converted-space"> </span></span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">You should also note why you'd want to do disable this (ie. the core will run</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">faster).</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""></div></blockquote><div><br class=""></div><div><br class=""></div>Sure Mikey, will add these information in commit message </div><div><br class=""></div><div>Thanks</div><div>Athira</div><div><br class=""></div><div><br class=""><blockquote type="cite" class=""><div class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">Secondly PowerISA v3.1 introduce filtering support for<br class="">PERF_SAMPLE_BRANCH_IND_CALL/COND. The patch adds BHRB filter support<br class="">for "ind_call" and "cond" in power10_bhrb_filter_map().<br class=""><br class="">'commit bb19af816025 ("powerpc/perf: Prevent kernel address leak to userspace<br class="">via BHRB buffer")'<br class="">added a check in bhrb_read() to filter the kernel address from BHRB buffer.<br class="">Patch here modified<br class="">it to avoid that check for PowerISA v3.1 based processors, since PowerISA v3.1<br class="">allows<br class="">only MSR[PR]=1 address to be written to BHRB buffer.<br class=""><br class="">Signed-off-by: Athira Rajeev <<a href="mailto:atrajeev@linux.vnet.ibm.com" class="">atrajeev@linux.vnet.ibm.com</a>><br class="">---<br class="">arch/powerpc/perf/core-book3s.c | 27 +++++++++++++++++++++------<br class="">arch/powerpc/perf/isa207-common.c | 13 +++++++++++++<br class="">arch/powerpc/perf/power10-pmu.c | 13 +++++++++++--<br class="">arch/powerpc/platforms/powernv/idle.c | 14 ++++++++++++++<br class=""></blockquote><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">This touches the idle code so we should get those guys on CC (adding Vaidy and</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Ego).</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">4 files changed, 59 insertions(+), 8 deletions(-)<br class=""><br class="">diff --git a/arch/powerpc/perf/core-book3s.c b/arch/powerpc/perf/core-book3s.c<br class="">index fad5159..9709606 100644<br class="">--- a/arch/powerpc/perf/core-book3s.c<br class="">+++ b/arch/powerpc/perf/core-book3s.c<br class="">@@ -466,9 +466,13 @@ static void power_pmu_bhrb_read(struct perf_event *event,<br class="">struct cpu_hw_events *<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* addresses at this point. Check the privileges before<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* exporting it to userspace (avoid exposure of regions<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* where we could have speculative execution)<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* Incase of ISA 310, BHRB will capture only user-space<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* address,hence include a check before filtering code<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>*/<br class="">-<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (is_kernel_addr(addr) && perf_allow_kernel(&event-<br class=""><blockquote type="cite" class="">attr) != 0)<br class=""></blockquote>-<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>continue;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (!(ppmu->flags & PPMU_ARCH_310S))<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (is_kernel_addr(addr) &&<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>perf_allow_kernel(&event->attr) != 0)<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>continue;<br class=""><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/* Branches are read most recent first (ie. mfbhrb 0 is<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* the most recent branch).<br class="">@@ -1212,7 +1216,7 @@ static void write_mmcr0(struct cpu_hw_events *cpuhw,<br class="">unsigned long mmcr0)<br class="">static void power_pmu_disable(struct pmu *pmu)<br class="">{<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>struct cpu_hw_events *cpuhw;<br class="">-<span class="Apple-tab-span" style="white-space: pre;"> </span>unsigned long flags, mmcr0, val;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>unsigned long flags, mmcr0, val, mmcra = 0;<br class=""><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>if (!ppmu)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>return;<br class="">@@ -1245,12 +1249,23 @@ static void power_pmu_disable(struct pmu *pmu)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mb();<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>isync();<br class=""><br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>val = mmcra = cpuhw->mmcr[2];<br class="">+<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/*<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* Disable instruction sampling if it was enabled<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>*/<br class="">-<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (cpuhw->mmcr[2] & MMCRA_SAMPLE_ENABLE) {<br class="">-<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mtspr(SPRN_MMCRA,<br class="">-<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span> cpuhw->mmcr[2] & ~MMCRA_SAMPLE_ENABLE);<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (cpuhw->mmcr[2] & MMCRA_SAMPLE_ENABLE)<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra = cpuhw->mmcr[2] & ~MMCRA_SAMPLE_ENABLE;<br class="">+<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/* Disable BHRB via mmcra [:26] for p10 if needed */<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (!(cpuhw->mmcr[2] & MMCRA_BHRB_DISABLE))<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra |= MMCRA_BHRB_DISABLE;<br class="">+<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/* Write SPRN_MMCRA if mmcra has either disabled<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* instruction sampling or BHRB<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>*/<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (val != mmcra) {<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mtspr(SPRN_MMCRA, mmcra);<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mb();<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>isync();<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class="">diff --git a/arch/powerpc/perf/isa207-common.c b/arch/powerpc/perf/isa207-<br class="">common.c<br class="">index 7d4839e..463d925 100644<br class="">--- a/arch/powerpc/perf/isa207-common.c<br class="">+++ b/arch/powerpc/perf/isa207-common.c<br class="">@@ -404,6 +404,12 @@ int isa207_compute_mmcr(u64 event[], int n_ev,<br class=""><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra = mmcr1 = mmcr2 = mmcr3 = 0;<br class=""><br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>/* Disable bhrb unless explicitly requested<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* by setting MMCRA [:26] bit.<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>*/<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>if (cpu_has_feature(CPU_FTR_ARCH_31))<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra |= MMCRA_BHRB_DISABLE;<br class="">+<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>/* Second pass: assign PMCs, set all MMCR1 fields */<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>for (i = 0; i < n_ev; ++i) {<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>pmc = (event[i] >> EVENT_PMC_SHIFT) & EVENT_PMC_MASK;<br class="">@@ -475,10 +481,17 @@ int isa207_compute_mmcr(u64 event[], int n_ev,<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class=""><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (event[i] & EVENT_WANTS_BHRB) {<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/* set MMCRA[:26] to 0 for Power10 to enable BHRB */<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (cpu_has_feature(CPU_FTR_ARCH_31))<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra &= ~MMCRA_BHRB_DISABLE;<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>val = (event[i] >> EVENT_IFM_SHIFT) & EVENT_IFM_MASK;<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra |= val << MMCRA_IFM_SHIFT;<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class=""><br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/* set MMCRA[:26] to 0 if there is user request for BHRB */<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (cpu_has_feature(CPU_FTR_ARCH_31) &&<br class="">has_branch_stack(pevents[i]))<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra &= ~MMCRA_BHRB_DISABLE;<br class="">+<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (pevents[i]->attr.exclude_user)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcr2 |= MMCR2_FCP(pmc);<br class=""><br class="">diff --git a/arch/powerpc/perf/power10-pmu.c b/arch/powerpc/perf/power10-pmu.c<br class="">index d64d69d..07fb919 100644<br class="">--- a/arch/powerpc/perf/power10-pmu.c<br class="">+++ b/arch/powerpc/perf/power10-pmu.c<br class="">@@ -82,6 +82,8 @@<br class=""><br class="">/* MMCRA IFM bits - POWER10 */<br class="">#define POWER10_MMCRA_IFM1<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>0x0000000040000000UL<br class="">+#define POWER10_MMCRA_IFM2<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>0x0000000080000000UL<br class="">+#define POWER10_MMCRA_IFM3<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>0x00000000C0000000UL<br class="">#define POWER10_MMCRA_BHRB_MASK<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>0x00000000C0000000UL<br class=""><br class="">/* Table of alternatives, sorted by column 0 */<br class="">@@ -233,8 +235,15 @@ static u64 power10_bhrb_filter_map(u64<br class="">branch_sample_type)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>if (branch_sample_type & PERF_SAMPLE_BRANCH_ANY_RETURN)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>return -1;<br class=""><br class="">-<span class="Apple-tab-span" style="white-space: pre;"> </span>if (branch_sample_type & PERF_SAMPLE_BRANCH_IND_CALL)<br class="">-<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>return -1;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>if (branch_sample_type & PERF_SAMPLE_BRANCH_IND_CALL) {<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>pmu_bhrb_filter |= POWER10_MMCRA_IFM2;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>return pmu_bhrb_filter;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class="">+<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>if (branch_sample_type & PERF_SAMPLE_BRANCH_COND) {<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>pmu_bhrb_filter |= POWER10_MMCRA_IFM3;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>return pmu_bhrb_filter;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class=""><br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>if (branch_sample_type & PERF_SAMPLE_BRANCH_CALL)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>return -1;<br class="">diff --git a/arch/powerpc/platforms/powernv/idle.c<br class="">b/arch/powerpc/platforms/powernv/idle.c<br class="">index 2dd4673..7db99c7 100644<br class="">--- a/arch/powerpc/platforms/powernv/idle.c<br class="">+++ b/arch/powerpc/platforms/powernv/idle.c<br class="">@@ -611,6 +611,7 @@ static unsigned long power9_idle_stop(unsigned long psscr,<br class="">bool mmu_on)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>unsigned long srr1;<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>unsigned long pls;<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>unsigned long mmcr0 = 0;<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>unsigned long mmcra_bhrb = 0;<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>struct p9_sprs sprs = {}; /* avoid false used-uninitialised */<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>bool sprs_saved = false;<br class=""><br class="">@@ -657,6 +658,15 @@ static unsigned long power9_idle_stop(unsigned long<br class="">psscr, bool mmu_on)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span> */<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcr0<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>= mfspr(SPRN_MMCR0);<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class="">+<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>if (cpu_has_feature(CPU_FTR_ARCH_31)) {<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/* POWER10 uses MMCRA[:26] as BHRB disable bit<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* to disable BHRB logic when not used. Hence Save and<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* restore MMCRA after a state-loss idle.<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>*/<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mmcra_bhrb<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>= mfspr(SPRN_MMCRA);<br class=""></blockquote><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><span style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none; float: none; display: inline !important;" class="">Why is the bhrb bit of mmcra special here?</span><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""></div></blockquote><div><br class=""></div>This to save/restore BHRB disable bit in state-loss idle state to make sure</div><div>we keep BHRB disabled if it was not enabled on request at runtime.</div><div><blockquote type="cite" class=""><div class=""><br style="caret-color: rgb(0, 0, 0); font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; text-decoration: none;" class=""><blockquote type="cite" style="font-family: Helvetica; font-size: 12px; font-style: normal; font-variant-caps: normal; font-weight: normal; letter-spacing: normal; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; text-decoration: none;" class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class="">+<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span>if ((psscr & PSSCR_RL_MASK) >= pnv_first_spr_loss_level) {<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>sprs.lpcr<span class="Apple-tab-span" style="white-space: pre;"> </span>= mfspr(SPRN_LPCR);<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>sprs.hfscr<span class="Apple-tab-span" style="white-space: pre;"> </span>= mfspr(SPRN_HFSCR);<br class="">@@ -721,6 +731,10 @@ static unsigned long power9_idle_stop(unsigned long<br class="">psscr, bool mmu_on)<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mtspr(SPRN_MMCR0, mmcr0);<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>}<br class=""><br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/* Reload MMCRA to restore BHRB disable bit for POWER10 */<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>if (cpu_has_feature(CPU_FTR_ARCH_31))<br class="">+<span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>mtspr(SPRN_MMCRA, mmcra_bhrb);<br class="">+<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span>/*<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* DD2.2 and earlier need to set then clear bit 60 in MMCRA<br class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-tab-span" style="white-space: pre;"> </span><span class="Apple-converted-space"> </span>* to ensure the PMU starts running.</blockquote></div></blockquote></div><br class=""></body></html>