From mboxrd@z Thu Jan 1 00:00:00 1970 From: Josh Poimboeuf Subject: Re: [patch V3 21/29] tracing: Use percpu stack trace buffer more intelligently Date: Thu, 25 Apr 2019 08:29:35 -0500 Message-ID: <20190425132935.ae35l5oybby5ddgl@treble> References: <20190425094453.875139013@linutronix.de> <20190425094803.066064076@linutronix.de> Mime-Version: 1.0 Content-Type: text/plain; charset="utf-8" Content-Transfer-Encoding: base64 Return-path: Content-Disposition: inline In-Reply-To: <20190425094803.066064076@linutronix.de> List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: intel-gfx-bounces@lists.freedesktop.org Sender: "Intel-gfx" To: Thomas Gleixner Cc: Mike Snitzer , David Airlie , Catalin Marinas , dri-devel@lists.freedesktop.org, linux-mm@kvack.org, dm-devel@redhat.com, Alexander Potapenko , Christoph Lameter , Miroslav Benes , Christoph Hellwig , Alasdair Kergon , Marek Szyprowski , linux-arch@vger.kernel.org, x86@kernel.org, kasan-dev@googlegroups.com, Johannes Thumshirn , Andrey Ryabinin , Alexey Dobriyan , intel-gfx@lists.freedesktop.org, David Rientjes , Akinobu Mita , Steven Rostedt , Josef Bacik , Mike Rapoport , Andy Lutomirski , David Sterba List-Id: dri-devel@lists.freedesktop.org T24gVGh1LCBBcHIgMjUsIDIwMTkgYXQgMTE6NDU6MTRBTSArMDIwMCwgVGhvbWFzIEdsZWl4bmVy IHdyb3RlOgo+IEBAIC0yNzg4LDI5ICsyNzk4LDMyIEBAIHN0YXRpYyB2b2lkIF9fZnRyYWNlX3Ry YWNlX3N0YWNrKHN0cnVjdAo+ICAJICovCj4gIAlwcmVlbXB0X2Rpc2FibGVfbm90cmFjZSgpOwo+ ICAKPiAtCXVzZV9zdGFjayA9IF9fdGhpc19jcHVfaW5jX3JldHVybihmdHJhY2Vfc3RhY2tfcmVz ZXJ2ZSk7Cj4gKwlzdGFja2lkeCA9IF9fdGhpc19jcHVfaW5jX3JldHVybihmdHJhY2Vfc3RhY2tf cmVzZXJ2ZSk7Cj4gKwo+ICsJLyogVGhpcyBzaG91bGQgbmV2ZXIgaGFwcGVuLiBJZiBpdCBkb2Vz LCB5ZWxsIG9uY2UgYW5kIHNraXAgKi8KPiArCWlmIChXQVJOX09OX09OQ0Uoc3RhY2tpZHggPj0g RlRSQUNFX0tTVEFDS19ORVNUSU5HKSkKPiArCQlnb3RvIG91dDsKPiArCj4gIAkvKgo+IC0JICog V2UgZG9uJ3QgbmVlZCBhbnkgYXRvbWljIHZhcmlhYmxlcywganVzdCBhIGJhcnJpZXIuCj4gLQkg KiBJZiBhbiBpbnRlcnJ1cHQgY29tZXMgaW4sIHdlIGRvbid0IGNhcmUsIGJlY2F1c2UgaXQgd291 bGQKPiAtCSAqIGhhdmUgZXhpdGVkIGFuZCBwdXQgdGhlIGNvdW50ZXIgYmFjayB0byB3aGF0IHdl IHdhbnQuCj4gLQkgKiBXZSBqdXN0IG5lZWQgYSBiYXJyaWVyIHRvIGtlZXAgZ2NjIGZyb20gbW92 aW5nIHRoaW5ncwo+IC0JICogYXJvdW5kLgo+ICsJICogVGhlIGFib3ZlIF9fdGhpc19jcHVfaW5j X3JldHVybigpIGlzICdhdG9taWMnIGNwdSBsb2NhbC4gQW4KPiArCSAqIGludGVycnVwdCB3aWxs IGVpdGhlciBzZWUgdGhlIHZhbHVlIHByZSBpbmNyZW1lbnQgb3IgcG9zdAo+ICsJICogaW5jcmVt ZW50LiBJZiB0aGUgaW50ZXJydXB0IGhhcHBlbnMgcHJlIGluY3JlbWVudCBpdCB3aWxsIGhhdmUK PiArCSAqIHJlc3RvcmVkIHRoZSBjb3VudGVyIHdoZW4gaXQgcmV0dXJucy4gIFdlIGp1c3QgbmVl ZCBhIGJhcnJpZXIgdG8KPiArCSAqIGtlZXAgZ2NjIGZyb20gbW92aW5nIHRoaW5ncyBhcm91bmQu Cj4gIAkgKi8KPiAgCWJhcnJpZXIoKTsKPiAtCWlmICh1c2Vfc3RhY2sgPT0gMSkgewo+IC0JCXRy YWNlLmVudHJpZXMJCT0gdGhpc19jcHVfcHRyKGZ0cmFjZV9zdGFjay5jYWxscyk7Cj4gLQkJdHJh Y2UubWF4X2VudHJpZXMJPSBGVFJBQ0VfU1RBQ0tfTUFYX0VOVFJJRVM7Cj4gLQo+IC0JCWlmIChy ZWdzKQo+IC0JCQlzYXZlX3N0YWNrX3RyYWNlX3JlZ3MocmVncywgJnRyYWNlKTsKPiAtCQllbHNl Cj4gLQkJCXNhdmVfc3RhY2tfdHJhY2UoJnRyYWNlKTsKPiAtCj4gLQkJaWYgKHRyYWNlLm5yX2Vu dHJpZXMgPiBzaXplKQo+IC0JCQlzaXplID0gdHJhY2UubnJfZW50cmllczsKPiAtCX0gZWxzZQo+ IC0JCS8qIEZyb20gbm93IG9uLCB1c2Vfc3RhY2sgaXMgYSBib29sZWFuICovCj4gLQkJdXNlX3N0 YWNrID0gMDsKPiArCj4gKwlmc3RhY2sgPSB0aGlzX2NwdV9wdHIoZnRyYWNlX3N0YWNrcy5zdGFj a3MpICsgKHN0YWNraWR4IC0gMSk7CgpuaXQ6IGl0IHdvdWxkIGJlIHNsaWdodGx5IGxlc3Mgc3Vy cHJpc2luZyBpZiBzdGFja2lkeCB3ZXJlIDAtYmFzZWQ6CgpkaWZmIC0tZ2l0IGEva2VybmVsL3Ry YWNlL3RyYWNlLmMgYi9rZXJuZWwvdHJhY2UvdHJhY2UuYwppbmRleCBkM2Y2ZWM3ZWI3MjkuLjRm YzkzMDA0ZmVhYiAxMDA2NDQKLS0tIGEva2VybmVsL3RyYWNlL3RyYWNlLmMKKysrIGIva2VybmVs L3RyYWNlL3RyYWNlLmMKQEAgLTI3OTgsMTAgKzI3OTgsMTAgQEAgc3RhdGljIHZvaWQgX19mdHJh Y2VfdHJhY2Vfc3RhY2soc3RydWN0IHJpbmdfYnVmZmVyICpidWZmZXIsCiAJICovCiAJcHJlZW1w dF9kaXNhYmxlX25vdHJhY2UoKTsKIAotCXN0YWNraWR4ID0gX190aGlzX2NwdV9pbmNfcmV0dXJu KGZ0cmFjZV9zdGFja19yZXNlcnZlKTsKKwlzdGFja2lkeCA9IF9fdGhpc19jcHVfaW5jX3JldHVy bihmdHJhY2Vfc3RhY2tfcmVzZXJ2ZSkgLSAxOwogCiAJLyogVGhpcyBzaG91bGQgbmV2ZXIgaGFw cGVuLiBJZiBpdCBkb2VzLCB5ZWxsIG9uY2UgYW5kIHNraXAgKi8KLQlpZiAoV0FSTl9PTl9PTkNF KHN0YWNraWR4ID49IEZUUkFDRV9LU1RBQ0tfTkVTVElORykpCisJaWYgKFdBUk5fT05fT05DRShz dGFja2lkeCA+IEZUUkFDRV9LU1RBQ0tfTkVTVElORykpCiAJCWdvdG8gb3V0OwogCiAJLyoKQEAg LTI4MTMsNyArMjgxMyw3IEBAIHN0YXRpYyB2b2lkIF9fZnRyYWNlX3RyYWNlX3N0YWNrKHN0cnVj dCByaW5nX2J1ZmZlciAqYnVmZmVyLAogCSAqLwogCWJhcnJpZXIoKTsKIAotCWZzdGFjayA9IHRo aXNfY3B1X3B0cihmdHJhY2Vfc3RhY2tzLnN0YWNrcykgKyAoc3RhY2tpZHggLSAxKTsKKwlmc3Rh Y2sgPSB0aGlzX2NwdV9wdHIoZnRyYWNlX3N0YWNrcy5zdGFja3MpICsgc3RhY2tpZHg7CiAJdHJh Y2UuZW50cmllcwkJPSBmc3RhY2stPmNhbGxzOwogCXRyYWNlLm1heF9lbnRyaWVzCT0gRlRSQUNF X0tTVEFDS19FTlRSSUVTOwogCl9fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19fX19f X19fX19fX19fCkludGVsLWdmeCBtYWlsaW5nIGxpc3QKSW50ZWwtZ2Z4QGxpc3RzLmZyZWVkZXNr dG9wLm9yZwpodHRwczovL2xpc3RzLmZyZWVkZXNrdG9wLm9yZy9tYWlsbWFuL2xpc3RpbmZvL2lu dGVsLWdmeA==